WO2010063817A2 - Device and method for compacting or compressing a gas - Google Patents

Abstract

The invention relates to a device for compressing or relieving a gaseous working medium using a hydraulic fluid, comprising a first adiabatic cylinder (8, 108) and a second adiabatic cylinder (7, 107) hydraulically connected to the first cylinder (8, 108) through a device for feeding (11) or discharging (111) energy, wherein (a) in a first state the gaseous working medium is located in the first adiabatic cylinder (8, 108) and the hydraulic fluid is located in the second adiabatic cylinder (7, 107); (b) in a first step the hydraulic fluid is led from the second adiabatic cylinder (7, 107) to the first adiabatic cylinder (8, 108), wherein the hydraulic fluid passes by the device for feeding (11) or discharging (111) energy; (c) in a second state the gaseous working medium is located in the second adiabatic cylinder (7, 107) and the hydraulic fluid is located in the first adiabatic cylinder (8, 108); (d) in a second step the hydraulic fluid is led from the first adiabatic cylinder (8, 108) to the second adiabatic cylinder (7, 107), wherein the hydraulic fluid passes by the device for feeding (11) or discharging (111) energy; and (e) the first step (b) is carried out when the second state is reached and then the second step (d) is carried out when the first state is reached, in repetitive fashion.

Description

 description

Apparatus and method for compressing or compressing a gas

The invention relates to an arrangement for compression or compression of a gaseous working fluid. It further relates to a method for compressing or compressing a gaseous working fluid.

The compression or expansion of gases has found a ready application in the energy industry. For example, the expansion of gases is used in processes for generating electrical or mechanical energy from other forms of energy, such as thermal energy. In so-called ORC processes (OCR = Organic Rankine Cycle), heat energy is converted into electrical energy by means of a gaseous or liquid working medium, with the exception of water.

In contrast, the compression of gases is used in heat pumps. In the compressor units of the heat pumps, among other things, working means with high compression end pressures and / or high pressure ratios are used. Such working agents are in particular carbon dioxide or ammonia. Furthermore, the compression of gases in a compressor unit is used for energy storage, as is the case for example in compressed air reservoirs. Another application of gas compression is isothermal compression, which requires separation or removal of the heat of compression. In addition, gases are compressed which pose a risk of explosion.

For the compression of gases in the range of small to medium power mainly roll and reciprocating compressors are used, while in the range of medium to large powers screw or turbomachinery are used.

In the expansion of gases - especially for OCR processes - in the medium power range predominantly reciprocating or rotary piston engines and in large scale turbo or screw compressor. By contrast, in the small power range, less than 10 kW electrical, so far no economic facilities have been built, where an ORC process could be applied. Only on the basis of the Stirling engine so-called "mini combined heat and power plants" were built.

However, the devices used for compression have certain disadvantages. In these machines, a volume displacement by pistons is achieved mechanically, which often requires the use of lubricating oil, on the one hand to protect the mechanics and, on the other hand, better sealing between the piston and the cylinder wall. This leads to unnecessary energy losses and environmental pollution and makes such compressor consuming and costly. Rarely, these types of compressor achieve an isentropic efficiency of more than 75%.

However, membrane and turbo compressors are an exception. In membrane compressors, a membrane is driven mechanically or hydraulically, which then causes the volume displacement of the gas. These compressors do not require a lubricating oil for sealing and achieve isentropic efficiencies of 90%. In turbocompressors, the gas to be compressed is accelerated by a paddle wheel and then the kinetic energy is converted into pressure in a diffuser. It is rare for the use of lubricating oil. However, the paddle wheels require very high speeds in order to achieve acceptable efficiencies. Furthermore, large volume flows must be promoted, which in turn limits the use of such machines to high performance.

The devices used so far for the expansion of gases also have various disadvantages. Although the Stirling cogeneration units used in the small power range have good efficiencies, the power density is relatively poor in these systems, especially in the low temperature range. For this reason, such systems are often large and expensive, which in turn has a negative impact on their efficiency. ORC processes are conditional operated by the turbo or screw compressor only economical systems in the medium and large power range. This also applies to compression.

Another problem is the generation of electricity from locally generated low-temperature heat in industrial areas, but also the local generation of solar thermal energy from new or existing plants. According to the prior art, the resulting low-temperature heat by ORC processes or thermocouples consuming and partly uneconomical converted into electrical energy. In particular, the isentropic relaxation in ORC processes leads to a further exergetic devaluation of heat. An exception are Stirling machines, which are technically quite easy to convert low-temperature heat into electrical energy. However, these require large volumes of work to deliver reasonably acceptable benefits. However, this leads to a thermodynamic condition whose efficiency drops sharply.

From US 2,772,543 a device is known which compresses a gas for refrigeration of mobile cold by a hydraulic pump. Disadvantage of this device is the hydraulic connection, so that the cyclic compression takes place by switching the flow direction to the hydraulic pump. This results in considerable problems in the system. By switching the flow direction arises as a result of the stoppage of the pump, a dead time in which no working fluid can be promoted. To compensate for this, components such as cylinder and pump must be oversized. Furthermore, large gas buffers must be introduced into the suction or pressure line in order to avoid pulsation and high control fluctuations on the valves.

The object of the invention is to eliminate the disadvantages of the prior art. In particular, an apparatus for compression or expansion of a gas is to be specified, which has a high degree of efficiency, can be realized cost-effectively, and an economical application, in particular in the case of ORC processes in installations with low and medium outputs in the low-temperature range. rich allows. Furthermore, a method for compression or expansion of a gas is to be specified. Finally, a method and a system are to be specified, which eliminates the hitherto insufficient conversion of low-temperature heat into electrical or mechanical work.

This object is solved by the features of claims 1 and 8. Advantageous embodiments of the invention will become apparent from the features of claims 2 to 7 and 9 to 15.

According to the invention, a device for compressing or relaxing a gaseous working fluid by means of a hydraulic fluid, comprising a first adiabatic cylinder and a second adiabatic cylinder, which is hydraulically connected to the first cylinder via a device for supplying or dissipating energy, is provided , in which

(a) in a first state, the gaseous working fluid is in the first adiabatic cylinder and the hydraulic fluid is in the second adiabatic cylinder;

(B) in a first step, the hydraulic fluid from the second adiabatic cylinder is guided in the first adiabatic cylinder, wherein the hydraulic fluid passes through the means for supplying or dissipating energy;

(c) in a second state, the gaseous working fluid is in the second adiabatic cylinder and the hydraulic fluid is in the first adiabatic cylinder;

(D) in a second step, the hydraulic fluid from the first adiabatic cylinder in the second adiabatic cylinder is guided, wherein the hydraulic fluid passes through the means for supplying or dissipating energy; and (E) the first step (b) upon reaching the second state and then the second step (d) are repeatedly executed upon reaching the first state.

The device preferably comprises at least one three-way valve arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder. By means of the at least one three-way valve, the flow direction of the hydraulic fluid can be determined. Particularly preferably, two three-way valves are provided, which are arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder.

By the introduction of three-way valves, a changeover of the flow direction at the pump is not required. Thus, a standstill of the pump and thus a dead time in which no working fluid can be promoted avoided. In comparison to US Pat. No. 2,772,543, the cylinders can be dimensioned substantially smaller, since a continuous compression of the gas takes place and thus a sustained output of the pump is granted. As a result, far less severe mass flow fluctuations occur. This results in much greater technical possibilities. Accordingly, the invention is superior to the device of US 2,772,543 from a technical as well as economical point of view.

The invention is based on the expansion or compression of gases by volume displacement with the aid of a hydraulic fluid, which undergoes an energy supply due to a pressure increase in the case of compression by a hydraulic pump or in the case of expansion by a hydraulic motor energy removal due to a pressure drop.

The gaseous working fluid is preferably a technical gas, for example carbon dioxide, oxygen, air, nitrogen, argon, ammonia, helium, propane, hydrogen and / or nitrous oxide. Preferred gaseous working agents are Oxygen, air, nitrogen and carbon dioxide. A particularly preferred gaseous working fluid is carbon dioxide. The gaseous working fluid is also referred to below as gas.

The hydraulic fluid is preferably water. The first and second cylinders preferably have the same inner volumes.

It can be provided that in the adiabatic cylinders, the hydraulic fluid and the gaseous working fluid are separated from one another in order to prevent the release of the gaseous working fluid in the hydraulic fluid. For this separation, a separating element, for example a piston or a membrane, can be provided in each of the cylinders. The separating element, which completely separates the gaseous working fluid from the hydraulic fluid, is movable in the cylinder along the longitudinal axis, so that its position may change depending on the pressure ratios in the cylinder.

An adiabatic cylinder is here understood to mean a cylinder which has no or the lowest possible heat exchange with the environment. This can be achieved by insulating the cylinders. In the cylinders, the working gas temperature can be limited by introducing heat exchangers.

Under one of the cylinders is not necessarily a geometric cylinder to understand. Rather, a cylinder can also be a container of any desired shape as long as it can receive the hydraulic fluid and / or the gaseous working fluid.

The terms "compression" and "compression" are used synonymously here. Similarly, the terms "expansion" and "relaxation" are used interchangeably.

A completely filled cylinder is understood to mean a cylinder which is either completely or at least 98% with the gaseous working medium or the Hydraulic fluid is filled at a predetermined temperature and a predetermined pressure.

The device has a comparatively simple structure, since all the components used are mass-produced and therefore cost-effective to procure. Furthermore, a simple conversion from the device for expansion of a gas (= expansion machine) to the device for compressing a gas (= compression machine) or vice versa is possible.

Using water hydraulics avoids exposure to oil or other lubricants and working materials. By means of the dimensioning of the two cylinders, any pressure conditions can be selected taking into account the operating points of the hydraulic pump or hydraulic motor. Very good machine efficiencies of 90 to 95% are achieved.

The invention allows for the first time an economic application of the expansion of gases in ORC processes with low and medium power in the low temperature range (> = 200 ⁰ C) when using carbon dioxide (R744) as a working fluid. Under low power here <50 kW electric, under average power: 51 kW> Electric power <500 kW understood.

Device for compressing a gas (compression machine) In one embodiment, the invention is directed to a device for compressing the gaseous working fluid, in which

the first adiabatic cylinder is connected via a first valve to a first conduit into which compressed gaseous working fluid can flow from the first adiabatic cylinder (the first conduit is also referred to as a pressure conduit in connection with the compression of a gas); - The first adiabatic cylinder is connected via a second valve to a second line from which relaxed gaseous working fluid in the first adiabatic cylinder can flow (the second conduit is also referred to as suction in connection with the compression of a gas);

- The second adiabatic cylinder is connected via a third valve to the first line (pressure line), in the compressed gaseous working fluid from the second adiabatic cylinder (7) can flow;

- The second adiabatic cylinder is connected via a fourth valve to the second line (suction line), can flow from the relaxed gaseous working fluid in the second adiabatic cylinder;

the means for supplying energy is a hydraulic pump which increases the pressure of the hydraulic fluid passing through the hydraulic pump;

in which

- In the first state and the second state, the first, second, third and fourth valve of the two cylinders is closed;

in the first step, in which the hydraulic fluid from the second adiabatic cylinder is fed into the first adiabatic cylinder, i) the gaseous working fluid in the first adiabatic cylinder 8 is compressed to a predetermined pressure, as soon as the gaseous Working fluid has reached the predetermined pressure, the first valve opens, so that the compressed gaseous working fluid i- sobar flows into the first line (pressure line); and (ii) the pressure in the second adiabatic cylinder decreases to a predetermined value, and as soon as the predetermined pressure in the second adiabatic cylinder is reached, the fourth valve opens so that expanded gaseous working fluid from the second conduit (suction conduit) enters the second adiabatic cylinder flows; and - In the second step, in which the hydraulic fluid from the first adiabatic cylinder is fed into the second adiabatic cylinder, (i) the gaseous working fluid in the second adiabatic cylinder is compressed to a predetermined pressure, as soon as the gaseous working fluid exceeds the predetermined Pressure has reached, the third valve opens, so that the compressed gaseous working fluid isobarically flows into the first line (pressure line); and (ii) the pressure in the first adiabatic cylinder decreases to a predetermined value, and as soon as the predetermined pressure in the first adiabatic cylinder is reached, the second valve opens so that expanded gaseous working fluid from the second conduit (suction conduit) enters the first adiabatic cylinder flows.

The flow direction of the hydraulic fluid is expediently determined via two three-way valves, which are arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder. The two three-way valves are switched simultaneously to change the direction of flow.

The first, second, third and fourth valves are expediently check valves.

The control of the first, second, third and fourth valves and the three-way valves can be effected via a control unit.

Preferably, the first line (pressure line), flows in the compressed gaseous working fluid, connected via an expansion valve to the second line (2), in which the compressed gaseous working fluid is expanded, so that the working fluid is circulated.

In one embodiment, at least one, preferably two cylinders of the device for compressing a gas may each be assigned a heat exchanger.

This embodiment enables an isothermal compression of the gas. The hy- Draulikflüssigkeit, which flows from one cylinder into the other cylinder, passes through the heat exchanger and is cooled there. Then it is passed through a nozzle in the cylinder and sprayed there. In this way, the hydraulic fluid can absorb the heat of compression generated during the compression of the gas. The hydraulic fluid heats up only slightly. The gas only absorbs the proportion of pressure energy and stores it. It absorbs only a small part of the heat of compression. After switching the direction of flow of the hydraulic fluid, the hydraulic fluid again passes through a heat exchanger on the way from the one cylinder to the other cylinder, in which the heat of the hydraulic fluid is removed again from the heat of compression.

Device for expanding a gas (expansion machine) In one embodiment, the invention is directed to a device for relaxing the gaseous working medium, in which

- The first adiabatic cylinder is connected via a first valve and a first three-way valve with a first line from which compressed gaseous working fluid can flow into the first adiabatic cylinder;

- The first adiabatic cylinder via a second valve and a second three-way valve is connected to a second line, can flow into the relaxed gaseous working fluid from the first adiabatic cylinder;

the second adiabatic cylinder is connected via a third valve and the first three-way valve is connected to the first line, from which compressed gaseous working fluid can flow into the second adiabatic cylinder;

the second adiabatic cylinder is connected via a fourth valve and the second three-way valve is connected to the second line, into which relaxed gaseous working fluid can flow into the second adiabatic cylinder; the means for dissipating energy is a hydraulic motor which reduces the pressure of the hydraulic fluid passing through the hydraulic motor;

in which

- In the first state and the second state, the first, second, third and fourth valve of the two cylinders is closed;

- In the first step, in which the hydraulic fluid from the second adiabatic cylinder is guided into the first adiabatic cylinder, (i) via the opened third valve compressed gaseous working fluid from the first conduit into the second adiabatic cylinder, so that the hydraulic fluid from is displaced from the second adiabatic cylinder and flows into the first adiabatic cylinder; and (ii) released gaseous working fluid from the first adiabatic cylinder flows via the opened second valve into the second conduit;

in the second step, in which the hydraulic fluid is conducted from the first adiabatic cylinder into the second adiabatic cylinder, i) compressed gaseous working medium via the opened first valve flows into the first adiabatic cylinder, so that the hydraulic fluid from the first adiabatic cylinder is displaced and flows into the second adiabatic cylinder; and (ii) relaxed gaseous working fluid from the second adiabatic cylinder flows via the opened fourth valve into the second conduit.

Conveniently, the flow direction of the hydraulic fluid is determined via two three-way valves, which are arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder. The flow of the compressed gaseous working fluid from the first conduit to the first adiabatic cylinder or to the second adiabatic cylinder is determined by the first three-way valve. The flow of the relaxed gaseous working fluid the first adiabatic cylinder or the second adiabatic cylinder into the second conduit is determined by the second three-way valve. These four three-way valves are preferably synchronized, so that the flow direction of the hydraulic fluid and the supply of compressed working fluid and the discharge of relaxed working fluid are changed simultaneously.

The first, second, third and fourth valves are expediently check valves.

The control of the first, second, third and fourth valves and the Dreiwegeventi- Ie can be done via a control unit.

Preferably, the second conduit, in which relaxed gaseous working fluid flows, is connected via a hydraulic pump to the first conduit, in which the expanded gaseous working fluid is compressed, so that the gaseous working fluid is recirculated.

According to the invention there is further provided a method of compressing or relaxing a gaseous working fluid by means of a hydraulic fluid in a device comprising a first adiabatic cylinder and a second adiabatic cylinder hydraulically connected to the first cylinder via a means for supplying or discharging energy connected, provided,

(a) in a first state, the gaseous working fluid is in the first adiabatic cylinder and the hydraulic fluid is in the second adiabatic cylinder;

(B) in a first step, the hydraulic fluid from the second adiabatic cylinder is guided in the first adiabatic cylinder, wherein the hydraulic fluid passes through the means for supplying or dissipating energy; (c) in a second state, the gaseous working fluid is in the second adiabatic cylinder and the hydraulic fluid is in the first adiabatic cylinder;

(D) in a second step, the hydraulic fluid from the first adiabatic cylinder is guided in the second adiabatic cylinder, wherein the hydraulic fluid passes through the means for supplying or dissipating energy; and

(E) the first step (b) upon reaching the second state and then the second step (d) are repeatedly executed upon reaching the first state.

The inventive method is preferably carried out with the device according to the invention.

Method for compressing a gas by means of a compression machine

In one embodiment, the invention is directed to a method of compressing the gaseous working fluid in which

- The first adiabatic cylinder is connected via a first valve with a first line (pressure line), can flow into the compressed gaseous working fluid from the first adiabatic cylinder;

- The first adiabatic cylinder is connected via a second valve to a second line (suction line), can flow from the relaxed gaseous working fluid in the first adiabatic cylinder;

- The second adiabatic cylinder is connected via a third valve to the first line (pressure line), can flow into the compressed gaseous working fluid from the second adiabatic cylinder; - The second adiabatic cylinder is connected via a fourth valve to the second line (suction line), can flow from the relaxed gaseous working fluid in the second adiabatic cylinder;

the means for supplying energy is a hydraulic pump which increases the pressure of the hydraulic fluid passing through the hydraulic pump;

in which

- In the first state and the second state, the first, second, third and fourth valve of the two cylinders is closed;

in the first step, in which the hydraulic fluid from the second adiabatic cylinder is fed into the first adiabatic cylinder, i) the gaseous working fluid in the first adiabatic cylinder is compressed to a predetermined pressure, as soon as the gaseous working fluid has reached the predetermined pressure, the first valve opens, so that the compressed gaseous working fluid isobarically flows into the first conduit; and (ii) the pressure in the second adiabatic cylinder decreases to a predetermined value, and as soon as the predetermined pressure in the second adiabatic cylinder is reached, the fourth valve opens so that expanded gaseous working fluid flows into the second adiabatic cylinder; and

in the second step, in which the hydraulic fluid is conducted from the first adiabatic cylinder into the second adiabatic cylinder, (i) the gaseous working fluid in the second adiabatic cylinder is compressed to a predetermined pressure, as soon as the gaseous working fluid has reached the predetermined pressure, the third valve opens, so that the compressed gaseous working fluid isobarically flows into the first line (pressure line); and (ii) the pressure in the first adiabatic cylinder decreases to a predetermined value, and as soon as the predetermined pressure in the first adiabatic cylinder is reached, the second valve opens so that expanded gaseous working fluid flows into the first adiabatic cylinder , The flow direction of the hydraulic fluid is expediently determined via two three-way valves, which are arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder. The two three-way valves are switched simultaneously to change the direction of flow.

The first, second, third and fourth valves are expediently check valves.

The control of the first, second, third and fourth valves and the three-way valves can be effected via a control unit.

Preferably, the first line (pressure line), in which compressed gaseous working fluid flows, is connected via an expansion valve to the second line (2), in which the compressed gaseous working fluid is expanded, so that the working fluid is recirculated.

The method of compressing the gaseous working fluid is described in more detail below:

The gaseous working fluid, which completely fills the first adiabatic cylinder, is compressed by a hydraulic fluid until a desired pressure builds up. At the same time, the hydraulic fluid is taken from the second adiabatic cylinder, which is hydraulically connected to the first adiabatic cylinder. This reduces the pressure in the second adiabatic cylinder to a desired value. When this is reached, the second check valve opens and allows gas to flow from a suction line into the second cylinder. The extracted hydraulic fluid flows through lines to a hydraulic pump, where it experiences an increase in pressure due to energy supply and is then returned to the first cylinder. If the desired pressure is reached in the first cylinder, the third check valve opens and allows the compressed gas to escape isobarically into a pressure line. Once this process has been completed, the two 3-way valves now change the flow direction of the hydraulic fluid so that the hydraulic fluid is removed from the first cylinder, which is completely filled with hydraulic fluid, flows through the hydraulic pump and flows into the second cylinder.

The previously flowed into the second cylinder gas from the suction line is now compressed in the second cylinder by the hydraulic fluid. This closes the second check valve on the suction line. When a desired pressure is reached again, the first check valve on the second cylinder opens and in turn allows the compressed gas to escape isobarically. At the same time, the pressure in the first cylinder, from which the hydraulic fluid is withdrawn, drops until a fourth check valve on the suction line opens and gas flows into the first cylinder.

If the second cylinder is completely filled with hydraulic fluid, the two 3-way valves again change the direction of flow so that the hydraulic fluid is again taken out of the second cylinder and flows into the first cylinder. This closes the cycle and a constant compression of a gas is guaranteed.

In one embodiment, at least one, preferably two cylinders of the device for compressing a gas are each associated with a heat exchanger. This embodiment enables an isothermal compression of the gas. The hydraulic fluid that flows into the other cylinder from one cylinder passes through the heat exchanger and is cooled down there. Then it is passed through nozzle into the cylinder and sprayed there. In this way, the hydraulic fluid can absorb the heat of compression generated during the compression of the gas. The hydraulic fluid heats up only slightly. The gas only absorbs the proportion of pressure energy and stores it. It only takes up a small part the compression heat on. After the switching of the flow direction of the hydraulic fluid passes through the hydraulic fluid on the way from the one cylinder to the other cylinder again a heat exchanger in which the hydraulic fluid, the heat of compression is withdrawn.

Method for relaxing a gas (expansion machine)

In one embodiment, the invention is directed to a method of expanding the gaseous working fluid, in which

- The first adiabatic cylinder is connected via a first valve and a first three-way valve with a first line from which compressed gaseous working fluid can flow into the first adiabatic cylinder;

- The first adiabatic cylinder is connected via a second valve and a second three-way valve to a second line, can flow into the relaxed gaseous working fluid from the first adiabatic cylinder;

the second adiabatic cylinder is connected via a third valve and the first three-way valve is connected to the first line, from which compressed gaseous working fluid can flow into the second adiabatic cylinder;

the second adiabatic cylinder is connected via a fourth valve and the second three-way valve is connected to the second line, into which relaxed gaseous working fluid can flow into the second adiabatic cylinder;

the means for dissipating energy is a hydraulic motor which reduces the pressure of the hydraulic fluid passing through the hydraulic motor;

in which - In the first state and the second state, the first, second, third and fourth valve of the two cylinders is closed;

in the first step, in which the hydraulic fluid from the second adiabatic cylinder is guided into the first adiabatic cylinder, (i) via the opened third

Valve compressed gaseous working fluid from the first conduit into the second adiabatic cylinder flows, so that the hydraulic fluid is displaced from the second adiabatic cylinder and flows into the first adiabatic cylinder; and (ii) relaxed gaseous working fluid from the first adiabatic cylinder flows into the second conduit via the opened second valve;

in the second step, in which the hydraulic fluid is conducted from the first adiabatic cylinder into the second adiabatic cylinder, i) compressed gaseous working medium via the opened first valve flows into the first adiabatic cylinder, so that the hydraulic fluid from the first adiabatic cylinder is displaced and flows into the second adiabatic cylinder; and (ii) relaxed gaseous working fluid from the second adiabatic cylinder flows via the opened fourth valve into the second conduit.

Conveniently, the flow direction of the hydraulic fluid is determined via two three-way valves, which are arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder. The flow of the compressed gaseous working fluid from the first conduit to the first adiabatic cylinder or to the second adiabatic cylinder is determined by the first three-way valve. The flow of the expanded gaseous working fluid from the first adiabatic cylinder or the second adiabatic cylinder into the second conduit is determined by the second three-way valve. These four three-way valves are preferably synchronized, so that the flow direction of the hydraulic fluid and the supply of compressed working fluid and the discharge of relaxed working fluid are changed simultaneously. The first, second, third and fourth valves are expediently check valves.

The control of the first, second, third and fourth valves and the three-way valves can be effected via a control unit.

Preferably, the second conduit, in which relaxed gaseous working fluid flows, is connected via a hydraulic pump to the first conduit, in which the expanded gaseous working fluid is compressed, so that the gaseous working fluid is recirculated.

According to the invention, a method and apparatus for converting low temperature heat from industrial waste heat sources, but also low temperature solar thermal and geothermal are also provided. The device consists of at least two containers which are filled with a fluid and hydraulically connected by an engine. The device is operated by alternately cyclic loading and unloading of the container with low temperature heat and ambient heat. In this way, the conversion of low temperature heat into electrical or mechanical work is improved. The erfmdungsge- Permitted method is economically advantageous. The required device requires little space.

In the cycle of loading of the first container, pressure increases as a result of the passage of low-temperature heat through an integrated heat exchanger. By closing a valve mounted between the first container and the engine, the fluid undergoes isochoric change of state until a saturation pressure is established. Meanwhile, a pressure drop of the fluid takes place in the second container as a result of the passage of ambient heat through an integrated heat exchanger. This built pressure difference is degraded in a working machine, which is hydraulically appropriate between the two containers, degraded and converted into electrical or mechanical energy. By switching over flows in the second step, the ambient temperature now flows through the first container, which leads to pressure reduction, while in the second container, an increase in pressure takes place by supplying low-temperature heat. This pressure difference is in turn reduced in the engine and converted into electrical or mechanical energy, before taking place again by switching a pressure increase in the first container or a pressure reduction in the second container.

It is further provided according to the invention that carbon dioxide or another working fluid having a high critical pressure and a critical temperature near the available temperatures of the heat source and the heat sink is used.

The economic advantage of the invention is due to the high exergetic yield of the heat supplied and its conversion into the highest qualitative form of energy, namely electrical energy. Furthermore, this contributes to the reduction of existing cooling costs, especially when using industrial waste heat. Furthermore, it is possible with this invention to open up previously unused heat sources and to draw on the production of electrical energy. The method and the device are therefore particularly suitable for the flow of locally generated low-temperature heat from industrial areas, but also the local power generation of solar thermal energy on new or existing plants.

The invention will be explained in more detail below with reference to embodiments, which are not intended to limit the invention, with reference to the drawings. Show Fig. 1 shows a first embodiment of an inventive arrangement for

Compression of a gas;

2a shows a second embodiment of an arrangement according to the invention for expanding a gas;

FIG. 2b shows an altered second embodiment of an arrangement according to the invention for expansion of a gas; FIG.

3 shows a third embodiment of an arrangement according to the invention for the isothermal compression of a gas;

4 shows a fourth embodiment of the arrangement according to the invention for the isothermal expansion of a gas; and

Fig. 5 shows an arrangement according to one aspect of the invention for the conversion of low temperature heat into electrical energy.

Example 1 The arrangement for compressing a gas shown in Fig. 1 is a compressor of a heat pump with the refrigerant carbon dioxide (R744, CO ₂ ) and a hydraulic axial piston pump (manufactured by Danfoss, DE), which as hydraulic fluid (Hf) water used. The first cylinder and the second cylinder have the same internal volume. Open or close the check valves if there is a pressure difference between the components between which they are installed. When changing the flow, due to the two 3-way valves, close the check valves, since the pressure difference collapses.

Condition before step Ia and Ib Before the steps Ia and Ib, the second cylinder 7 is completely filled with water while the first cylinder 8 is completely filled with CO ₂ . The check valves 3, 4, 5 and 6 are closed.

Step Ia

In a completely filled with CO ₂ first cylinder 8 hydraulic fluid flows in and compresses the CO _{2 located there} , until a pressure of 95 bar builds up. The temperature of the CO _{2 increases} from the beginning of 30 ⁰ C to 113 ⁰ C. As soon as the pressure of 95 bar in the first cylinder 8 is reached, opens the third check valve (Rv) 6 and leaves the CO ₂ isobaric in the Pressure line (Dl) 1 escape, it builds up a pressure of about 95 bar in the pressure line 1.

Step Ib

Simultaneously with step 1a, the required hydraulic fluid is taken from the second cylinder 7, passed through the 3-way valve 9 and supplied to the hydraulic pump (Hp) 11. The hydraulic pump 11 pumps the water to a pressure of 95 bar and allows it to flow via the 3-way valve 10 into the first cylinder 8. The required electric power of 4.8 kW gets the hydraulic pump 11 from an electric motor 12. During the removal of the hydraulic fluid, the pressure in the second cylinder 7 drops to 37.7 bar. As soon as the pressure of 37.7 bar is reached in the second cylinder 7, the second check valve 4 opens and allows CO ₂ from the suction line (Sl) 2 to flow into the first cylinder 7.

State after steps Ia and Ib After steps Ia and Ib, the second cylinder 7 is completely filled with CO ₂ while the first cylinder 8 is completely filled with water. The check valves 3, 4, 5 and 6 are closed.

Step 2a In this state, the two 3-way valves 9 and 10 now change the flow direction of the water; this close the check valves 4 and 6, so that now the Water from the first cylinder 8 flows through the 3-way valve 10 through the hydraulic pump 11. In the hydraulic pump 11, the water experiences a pressure increase from 37.7 bar to 95 bar. Thereafter, the water is passed through the 3-way valve 9 in the second cylinder 7 and there compresses the CO ₂ from 37.7 to 95 bar, the CO _{2 changes} its temperature from 30 ⁰ C to 113 ⁰ C. As soon as the pressure of 95 bar in the second cylinder 7 has been reached, the first check valve 3 opens and in turn allows the CO _{2 to} escape isobarically into the pressure line 1.

Step 2b At the same time as step 2a falls in the first cylinder 8, however, the pressure. As soon as the pressure in the second cylinder has reached 37.7 bar, the fourth check valve 5 opens and allows CO _{2 to} flow from the suction line 2 into the cylinder 8. As soon as the second cylinder 7 is completely filled with CO ₂ , the two 3-way valves 9 and 10 change the flow direction of the hydraulic fluid, so that now the water flows from the second cylinder 7 via the hydraulic pump 11 to the first cylinder 8.

Condition after step 2a and 2b

After steps 2a and 2b, the second cylinder 7 is completely filled with water while the first cylinder 8 is completely filled with CO ₂ . This state thus corresponds to the state before steps Ia and Ib. The check valves 3, 4, 5 and 6 are closed. This completes the cycle and ensures continued compression of CO ₂ .

Cooling and relaxation of the CO ₂ The heated CO ₂ discharged in pressure line 1 in steps 1a and 2a is conducted in the pressure line 1 to a gas cooler 13 where it is cooled to 32 ^° C. countercurrently with water. The water heats up and absorbs about 21 kW from the CO ₂ . Subsequently, the water can be made available to a consumer 17 (for example, a building heating). After the CO ₂ has delivered 21 kW of heat output in the gas cooler 13, it is passed from the pressure line 1 to the inner heat exchanger 14. There, it heats countercurrently the CO ₂ from the suction line 2, wherein the CO ₂ in the pressure line 1 of 32 ⁰ C to 20.7 ⁰ C cools. Subsequently, the CO ₂ passes in the pressure line 1 to the expansion valve 15. By means of the expansion valve 15, the CO ₂ in the pressure line 1 is isenthalp relaxed from 95 bar to 37.7 bar in the two-phase region. In this case, the CO ₂ enters suction line. 2

Evaporation and heating of the CO2 In suction line 2, the CO _{2 is} fed to an evaporator 16. This takes 18 water from a well. With this water, the CO ₂ at 3 ⁰ C, again in countercurrent principle, evaporated and superheated to 6 ⁰ C, the CO ₂ 16.1 kW from the well water absorbs heat output.

After the CO _{2 is} completely evaporated in the evaporator 16, it is passed from the suction line 2 to the inner heat exchanger 14 and heated there from 6 ⁰ C to 30 ⁰ C and is then the hydraulic compressor available.

Performance figures Heat pump performance figures of 4.3 can be achieved with this heat pump (21 kW / 4.8 kW = 4.3). This is in contrast to the prior art, which only achieves a coefficient of performance of about 3.5 under the same conditions. Furthermore, can be completely dispensed with the use of lubricating oil.

Example 2

The arrangement shown in Fig. 2a-b for the expansion of a gas is an expansion machine of an ORC process with the working fluid carbon dioxide and a hydraulic axial piston motor (manufacturer: Fa. Danfoss, DE), which uses water as hydraulic fluid. The arrangement shown in Fig. 2a is substantially the same as that shown in Fig. 1 except that the check valves 103, 104, 105 and 106 on the cylinders 107, 108 are compared to the check valves 3, 4, 5 and 6 on the cylinders 7, 8 are exchanged in their flow direction and the hydraulic pump 11 is replaced by a hydraulic motor (Hm) 111. In addition, the two 3-way valves 119 and 120 still have to be installed in the lines 101 and 102 respectively.

The check valves open or close only when there is a pressure difference between the components between which they are installed. In the case of flow change due to the two 3-way valves, the check valves close because the pressure difference collapses.

Heating and compression of CO 2

In a hydraulic pump 15 liquid CO _{2 is} compressed from 60 bar to 100 bar. The CO _{2 is} heated from 19 ⁰ C to 26 ⁰ C and takes a power of 4.5 kW from the hydraulic pump 15, which operates with an efficiency of 95%, on.

Subsequently, the CO _{2 is passed} in line 101 to a heat exchanger 117 and there heated in countercurrent of water to 60 ⁰ C and evaporated. The CO ₂ removes 157 kW of heat from the water. The water comes from an industrial waste heat source 118.

State before steps Ia and Ib Before steps Ia and Ib, the second cylinder 7 is completely filled with water while the first cylinder 8 is completely filled with CO ₂ . The check valves 103, 104, 105 and 106 are closed.

Step Ia From the heat exchanger 117, the CO ₂ in line 101 passes through the 3-way valve 20 and the open check valve 103 to the second cylinder 107. The second Cylinder 107 is almost completely filled with water. The now penetrating CO ₂ displaces the water with 100 bar. This water is now passed via the 3-way valve 109 to the hydraulic motor 111, there relaxed to 60 bar and passed to the first cylinder 108 via the 3-way valve 110 (see step Ib). When the Ent- voltage of the hydraulic motor 111 outputs 14.9 kW shaft power to the generator 112 from. The generator 112 then converts the shaft power into electrical power. 14.2 kW electrical power is provided to a consumer. The efficiency of the hydraulic motor 111 is 92% and that of the generator 95%.

Step Ib

At the same time as step Ia, the water expanded to 60 bar in the hydraulic motor 111 fills the first cylinder 108. The CO ₂ located there is isobarically displaced into the line 2 via the opened non-return valve 105 and the three-way valve 119 at a pressure of 60 bar.

Condition after step Ia and Ib

After the steps Ia and Ib, the second cylinder 7 is completely filled with CO ₂ , while the first cylinder 8 is almost completely filled with water. The check valves 103, 104, 105 and 106 are closed.

Step 2a

Once the first cylinder 108 is almost completely filled with water, the 3-way valves 109, 110 and 119, 120 change the flow directions, so that now the CO ₂ from line 101 via the three-way valve 120 and the open check valve 106 in the first cylinder 108th can flow in and now displaces the water there. The water is passed so that it passes through the 3-way valves 109 and 110 and the hydraulic motor 111 to the second cylinder 107. Step 2b

At the same time as step 2a, the water relaxed in the hydraulic motor 111 to 60 bar fills the second cylinder 107. The CO ₂ located there is isobarged via the open check valve 104 and three-way valve 119 isobar at a pressure of 60 bar in the line 2.

Condition after step 2a and 2b

After the steps 2a and 2b, the second cylinder 7 is almost completely filled with water, while the first cylinder 8 is almost completely filled with CO ₂ . The check valves 103, 104, 105 and 106 are closed. This state thus corresponds to the state before steps Ia and Ib. This completes the cycle and ensures continued relaxation of CO ₂ .

Cooling and liquefaction of the CO2 Via line 102 now passes the CO ₂ at a pressure of 60 bar and a temperature of 23 ⁰ C in the condenser 13. There it is cooled in countercurrent to cooling tower water to 19 ⁰ C and liquefied. Subsequently, the now liquid CO ₂ returns to the hydraulic pump 15th

Example 2 shows that an ORC process, which is operated with the arrangement according to the invention for the expansion of a gas, is quite technically and economically feasible in the small and medium power range and relatively low temperatures with simple means.

The arrangement shown in Fig. 2b corresponds to the arrangement shown in Fig. 2a, except that in contrast to Fig. 2a, no check valves 103, 104, 105 and 106 are provided on the cylinders 107, 108. This further simplifies the process management.

In the embodiment shown in FIGS. 2a or 2b, pump 115 is replaced by an expansion valve or an expansion valve is connected in parallel provided to the pump 115, it is possible to get out of the relaxation of a gas out in its compression. Only the valves 119 and 120 are controlled so that upon reaching a selected pressure these open or close depending on the compressing or sucking cylinder. This switching from the expansion of a gas into the compression can take place during operation. The generator 112 then serves as a motor and supplies the hydraulic pump 111 with electrical energy. The heat source 118 then serves as a heat consumer, and the gas heater 117 is a gas cooler in heat pump operation. As a result of this switching, the device is operated either as a heat pump or power plant. Thus, excess heat can be converted into electrical energy in 118 or heat demand can be supplied by supplying electrical energy in generator 112 and waste heat from cooling water tower 114 to the consumer 118 by evaporation in condenser 113 and compression in the devices 101 to 111 in the form of high-temperature heat become.

Example 3

The arrangement shown in FIG. 3 for the isothermal compression of a gas corresponds to the embodiment shown in FIG. 1, with the exception of two additional heat exchangers through which hydraulic fluid 20, 25 is led to cool down. Like reference numerals have the same meaning as in Fig. 1. As a gaseous working fluid, air is used. The hydraulic fluid is water.

State before steps Ia and Ib Before steps Ia and Ib, the second cylinder 7 is completely filled with the hydraulic fluid while the first cylinder 8 is completely filled with air. The check valves 3, 4, 5, and 6 are closed.

Step 1a In a first cylinder 8, which is completely filled with air, cooled hydraulic fluid flows via nozzle 27 via heat exchanger 25 (see step Ib) compresses the air there until a first predetermined pressure builds up. The heat of compression is absorbed by the sprayed by means of nozzle 27 hydraulic fluid. In this case, the hydraulic fluid heats up slightly, while the air only absorbs and stores the proportion of pressure energy and absorbs only a very small part of the heat of compression.

As soon as the first predetermined pressure in the first cylinder 8 is reached, the third check valve (Rv) 6 opens and allows the air to escape isobarically into the pressure line (Dl) 1, during which the first predetermined pressure builds up in the pressure line 1.

Step Ib

Simultaneously with step Ia the second cylinder 7, the required hydraulic fluid is removed, passed through the open check valve 22 and the 3-way valve 9 and the hydraulic pump (Hp) 11 is supplied. The hydraulic pump 11 pumps the hydraulic fluid to the first predetermined pressure and allows it to flow via the 3-way valve 10 and the open check valve 24 to the heat exchanger 25. In this case, check valve 26 is closed in order to prevent direct penetration of the hydraulic fluid into the first cylinder 8.

In heat exchanger 25, the hydraulic fluid is cooled with cooling tower water, which has a lower temperature than the hydraulic fluid, in the countercurrent principle. The water comes from a cooling tower 21. After the cooling of the hydraulic fluid in heat exchanger 25, it flows via the nozzle 27 into the first cylinder 8 (see step Ia).

During the removal of the hydraulic fluid, the pressure in the second cylinder 7 decreases to the second predetermined pressure, which is lower than the first predetermined pressure. As soon as the second predetermined pressure is reached in the second cylinder 7, the second check valve 4 opens and allows air from the suction line (Sl) 2 to flow into the first cylinder 7. Condition after step Ia and Ib

After the steps Ia and Ib, the second cylinder 7 is completely filled with air, while the first cylinder 8 is completely filled with hydraulic fluid. The check valves 3, 4, 5, and 6 are closed.

Step 2a

In this state, now change the two 3-way valves 9 and 10, the flow direction of the water; In this case, the check valves 4, 6, 22 and 24 close, so that now the hydraulic fluid from the first cylinder 8 via the open check valve 26 and the 3-way valve 10 flows through the hydraulic pump 11. The closed check valve 22 prevents a direct penetration of the hydraulic fluid into the second cylinder 7. In the hydraulic pump 11, the hydraulic fluid undergoes a pressure increase from the second predetermined pressure to the first predetermined pressure. Thereafter, the hydraulic fluid is passed through the 3-way valve 9 and the open check valve 19 to the heat exchanger 21.

In heat exchanger 21, the hydraulic fluid with cooling tower water, which has a lower temperature than the hydraulic fluid, cooled in the countercurrent principle. The water comes from a cooling tower 21. After the cooling of the hydraulic fluid in heat exchanger 21, it flows via the nozzle 23 into the second cylinder 7, where it compresses the air from the second predetermined pressure to the first predetermined pressure. As soon as the first predetermined pressure in the second cylinder 7 has been reached, the first check valve 3 opens and in turn allows the air to escape isobarically into the pressure line 1.

The heat of compression is absorbed by the sprayed by means of nozzle 23 hydraulic fluid. In this case, the hydraulic fluid heats up slightly, while the air only absorbs and stores the proportion of pressure energy and absorbs only a very small part of the heat of compression. Step 2b

At the same time as step 2a, however, the pressure in the first cylinder 8 drops. As soon as the pressure in the second cylinder has reached the second predetermined pressure, the fourth check valve 5 opens and allows air from the suction line 2 to flow into the cylinder 8. As soon as the second cylinder 7 is completely filled with air, the two 3-way valves 9 and 10 change the flow direction of the hydraulic fluid, so that now the hydraulic fluid from the second cylinder 7 via the hydraulic pump 11 and the heat exchanger 21 flows to the first cylinder 8 and this is introduced via nozzle 27.

Condition after step 2a and 2b

After the steps 2a and 2b, the second cylinder 7 is completely filled with Hydraulikfiüssigkeit, while the first cylinder 8 is completely filled with air. This state thus corresponds to the state before steps Ia and Ib. The check valves 3, 4, 5 and 6 are closed. This closes the cycle and ensures continuous compression of the air while dissipating heat of compression.

Further components of the third embodiment of the invention

The remaining components and process steps are described in the sections "Cooling and relaxation of CO ₂ " and "Evaporation and heating of CO ₂ " of Example 1 and in Fig. 3, wherein in Example 3 air instead of CO _{2 is used} by as a gaseous working fluid , Alternatively, a storage vessel, for example, for air (compressed air) can be attached to the pressure line 1. The suction line would then extract the intake air from the atmosphere. The waste heat source 21 (cooling source) could be a storage vessel for water, in which the water required for the cooling of the hydraulic fluid is stored. In addition, other waste heat sources or solar collectors could be connected to it, which further heat the contents of the storage vessel at standstill. This heat can be returned later, if necessary, the stored air through heat exchangers again, which then can be relaxed by a force process, for example, the relaxation process described and to a very high efficiency greater than 80% (taking into account the free waste heat source) are converted into electrical or mechanical energy.

Example 4

Referring to Figure 4, a fourth embodiment of the invention for converting heat to engineering will be described. This is used, for example, in compressed air storage. In this case, a pressurized and heated to a higher temperature than that of the surrounding gas is used as the working medium. This device is intended to replace the turbine and achieve a much higher exergetic utilization.

In the initial state, container 208 is completely filled with a hydraulic fluid (Hf), while container 207 is filled only by air under atmospheric pressure. The valves 203 to 206 are closed.

Step 1 The air flowing under pressure from line 202 is directed into the container 208 via the opening valve 206. The hydraulic fluid assumes the same pressure as the incoming air. The now pressurized hydraulic fluid is released by appropriate position of the valves 211 and 212 via the hydraulic motor 215 in the container 207. The hydraulic fluid assumes ambient pressure because the valve is now open. As a result of the relaxation, mechanical energy is delivered to the hydraulic motor 215. At the same time, by positioning the valves 209 and 210, the hydraulic fluid from the reservoir 208 is circulated by the pump 214 and heated by the heat source 213. In the nozzle 218, the hydraulic fluid is sprayed into the container 208 again. As a result, the incoming air is maintained at its temperature level despite relaxation. This process takes place until so much air mass in the container 208 that this at Ambient pressure completely fills the container 208. When this condition is reached, valve 206 closes and isothermal expansion takes place by the supply of heat from heat source 213.

step 2

When the pressure in the container 208 is equal to that in the container 207 and container 207 is completely filled with hydraulic fluid, the valves 209 to 212 switch over and the valve 204 is closed. Subsequently, valves 203 and 206 are opened. Now the hot and pressurized air enters the container 207 and pressurizes the hydraulic fluid. This is now passed through the hydraulic motor 215 in the container 208 and thereby relaxed, this is done with the release of mechanical energy. At the same time, by circulating the hydraulic fluid from container 207 and heating it by heat source 213, the incoming air is heated from nozzle 217 by heating from the hydraulic fluid flowing into container 207. It comes back to isothermal relaxation until so much air has entered container 207 that it completely fills the container 207 under ambient pressure. When this condition is reached, the valve 203 closes and an isothermal expansion continues by supplying heat from the heat source 213. When container 208 is completely filled with hydraulic fluid, the valves 209 to 212 are switched over, the valve 205 is closed and the valve 206 is opened.

This completes the cycle to step 1. The continuous mechanical work is converted by the generator 216 into electrical energy.

This process allows for isothermal relaxation, allowing for the best physical conversion of heat into high-quality mechanical or electrical energy. Example 5

An embodiment of a low temperature power process will be described. In this example, a method of converting low-temperature industrial heat into electrical energy by means of the apparatus shown in FIG. 5 will be described. In order to avoid dead times on the engine, instead of necessarily two, four containers are used.

In the initial state, the containers 301 and 303 are filled with a carbon dioxide mass of 64 kg, while the containers 302 and 4 are filled with only 13 kg. The inner volumes of all containers 301 to 304 are the same size and are at 0.1 m ³ . Also, the pressure and temperature of all containers are the same size, the pressure is adjusted depending on the temperature. Since the containers have a temperature of 15 ⁰ C, prevails in all a pressure of 50 bar. The valves 309 to 312 are all in position A-> B, so that the container initially have no connection with each other and have a self-contained volume.

Step 1

The valves 316 and 317 are open in position C- A, thus waste heat at a temperature of 60 ⁰ C from the waste heat source 324 passes through the heat exchanger 305 in the container 301. It comes to heating of the carbon dioxide and increase the tank pressure to 160 bar, by isochoric state change (ZÄ). At the same time, the valves 322 and 323 in position A-> B and let flow from the heat sink 325 water at a temperature of 10 ⁰ C through the heat exchanger 308. Due to the cooling of the heat exchanger 308, condensation occurs in container 304, whereby a vapor pressure in the container of 45 bar occurs. This pressure difference between containers 301 and 304 is now released by switching valves 309 and 312. In this case, the carbon dioxide flows from container 301 through the heat exchanger 315, where it is optionally supercooled, in the hydraulic motor 313. In it comes to relax on the condensation pressure which prevails in the container 304. The expanded carbon dioxide is then passed into the container 304 and fills it. By continuous intake while relaxing In the container 301 by heat, this is maintained at a temperature of 60 ⁰ C, thereby resulting in isothermal relaxation. The container 304 is also continuously cooled with the heat sink 325. At the same time, the valves 318 and 319 go to position A-> B and cool the container 302 to a condensation pressure of 45 bar, while by positioning the valves 320 and 321 and supplying heat from the heat source 324, the container 303 on a pressure of 160 bar is brought by isochoric state change.

Step 2 When pressure equalization between tanks 301 and 304 is complete, valves 316 and 317 go to position A-> B and valves 322 and 323 go to position A-> C. As a result, the container 304 filled with carbon dioxide is heated with heat from the heat source 324. This builds up by isochoric state change to a pressure of 160 bar. The reduced in the container 301 to 13 kg of carbon dioxide is cooled by the switching of the valves 316 and 317 now using the heat sink 325, with a condensation pressure of 45 bar sets. Previously, the valves 309 and 310 go to position A-> B and close the containers 301 and 304, while the containers 302 and 303 are hydraulically connected by the valves 310 and 311, position C ^ B. This results in pressure equalization between the containers 303 and 302, wherein the carbon dioxide from container 303 flows through the heat exchanger 315 and the hydraulic motor 313 into the container 302. By relaxing to condensation pressure of container 302 in the hydraulic motor 313, there is the release of mechanical energy in the hydraulic motor 313. This happens again continuously by energy supply in the container 303 and cooling of the container 302 until a pressure equalization has set.

step 3

When pressure equalization between tanks 303 and 302 is achieved, valves 310 and 311 go to position A-> B and close the tanks again, while valves 309 and 312 go to positions C- ^ A and C- B, respectively. By further switching the

Valves 318 and 319 in position C ^ A and the valves 320 and 321 in position A-> B it comes in container 302 for heating and pressure increase to 160 bar, while in container 303 by cooling, a pressure of 45 bar sets. At the same time, the pressure difference prevailing between container 304 and 301, degraded by the hydraulic motor, now container 304 has a pressure of 160 bar, while in container 301, a pressure of 45 bar prevails. This is again done by supplying heat to container 304 while container 301 is cooled by heat sink 325.

Step 4 Once the pressure equalization between tanks 304 and 301 has been reached, valves 309 and 312 return to position A-> B, while valves 310 and 311 go to position C-A. The pressure drops between the containers 302 and 303 again, while the containers 301 and 304 produce a pressure difference by switching the valves 316 and 317, in position C ^ A, and the valves 322 and 323, in position A-> B build up.

If the pressure equalization between tank 302 and 303 is reached, closes by switching the valves 310 and 311, in position A-> B, and by switching the valves 309 and 312, in position C-> B or C-> A the circle and the starting point to step 1 is completed. This ensures a continuous release of mechanical energy to the generator 314, wherein a conversion of low-temperature waste heat into high-quality electrical energy takes place.

LIST OF REFERENCE NUMBERS

1 pressure line

2 suction line

3 first check valve

4 second check valve

5 fourth check valve

6 third check valve

7 second cylinder

8 first cylinder

9 3-way valve

10 3-way valve

11 hydraulic pump

12 electric motor

13 gas coolers

14 internal heat exchanger

15 expansion valve

16 evaporators

17 consumers

18 wells

19 check valve

20 heat exchangers

21 waste heat source

22 check valve

23 nozzle in the second cylinder 7

24 check valve

25 heat exchangers

26 check valve

27 nozzle in the second cylinder 8

101 first line 102 second line

103 first check valve

104 second check valve

105 fourth check valve 106 third check valve

107 second cylinder

108 he died

109 3-way valve

110 3-way valve 111 Hydraulic motor

112 generator

113 capacitor

114 cooling water tower

115 Hydraulic pump 116 Electric motor

117 heat exchangers

118 waste heat source

119 second 3-way valve

120 first 3-way valve

202 line

203 - 206 valves 207 containers

208 containers

209 - 212 valves

213 heat source

215 hydraulic motor 216 generator

217 nozzle 218 nozzle

301-304 container

305 - 308 heat exchangers 309-312 valves

313 hydraulic motor

314 generator

315 Heat exchanger 316-323 Valves 324 Heat source

325 heat sink

Claims

claims 1. A device for compression or expansion of a gaseous working fluid by means of a hydraulic fluid, comprising a first adiabatic cylinder (8, 108) and a second adiabatic cylinder (7, 107) with the first Cylinder (8, 108) via a means for supplying (11) or discharge (111) of energy is hydraulically connected, wherein (a) in a first state, the gaseous working fluid is in the first adiabatic cylinder (8, 108) and the hydraulic fluid is in the second adiabatic cylinder (7, 107); (B) in a first step, the hydraulic fluid from the second adiabatic cylinder (7, 107) in the first adiabatic cylinder (8, 108) is guided, wherein the hydraulic fluid, the means for supplying (11) or discharge (111) Energy happens; (c) in a second state, the gaseous working fluid is in the second adiabatic cylinder (7, 107) and the hydraulic fluid is in the first adiabatic cylinder (8, 108); (D) in a second step, the hydraulic fluid from the first adiabatic cylinder (8, 108) in the second adiabatic cylinder (7, 107) is guided, wherein the hydraulic fluid passes through the means for supplying (11) or discharge (111) of energy ; and (E) the first step (b) upon reaching the second state and then the second step (d) are repeatedly executed upon reaching the first state. 2. Apparatus according to claim 1 for the compression of the gaseous working fluid, characterized in that - The first adiabatic cylinder (8) via a first valve (3) with a first line (1) is connected, can flow into the compressed gaseous working fluid from the first adiabatic cylinder (8); - The first adiabatic cylinder (8) via a second valve (4) with a second line (2) is connected, can flow from the relaxed gaseous working fluid in the first adiabatic cylinder (8); - the second adiabatic cylinder (7) is connected via a third valve (6) to the first conduit (1) into which compressed gaseous working fluid from the second adiabatic cylinder (7) can flow; - the second adiabatic cylinder (7) is connected via a fourth valve (5) to the second conduit (2) from which relaxed gaseous working fluid can flow into the second adiabatic cylinder (7); the means for supplying (11) energy is a hydraulic pump (11) which increases the pressure of the hydraulic fluid passing through the hydraulic pump (11); in which - In the first state and the second state, the valves (3, 4, 5, 6) of the two cylinders (7, 8) are closed; in the first step, in which the hydraulic fluid from the second adiabatic cylinder (7) is guided into the first adiabatic cylinder (8), (i) the gaseous working fluid in the first adiabatic cylinder (8) is adjusted to a predetermined benen pressure is compressed, wherein, as soon as the gaseous working fluid has reached the predetermined pressure, the first valve (3) opens, so that the compressed gaseous working fluid isobarically flows into the first conduit (1); and (ii) the pressure in the second adiabatic cylinder (7) decreases to a predetermined value, and as soon as the predetermined pressure in the second adiabatic Cylinder (7) is reached, the fourth valve (5) opens, so that relaxed gaseous working fluid flows into the second adiabatic cylinder (7); and in the second step, in which the hydraulic fluid from the first adiabatic cylinder (8) is guided into the second adiabatic cylinder (7), (i) compresses the gaseous working fluid in the second adiabatic cylinder (7) to a predetermined pressure is, wherein, as soon as the gaseous working fluid has reached the predetermined pressure, the third valve (6) opens, so that the compressed gaseous working fluid isobarically flows into the first conduit (1); and (ii) the pressure in the first adiabatic cylinder (8) to a predetermined one Value decreases, as soon as the predetermined pressure in the first adiabatic cylinder (8) is reached, the second valve (4) opens, so that relaxed gaseous working fluid flows into the first adiabatic cylinder (8). 3. Apparatus according to claim 2, characterized in that the flow direction of the hydraulic fluid via three-way valves (9, 10) is determined, which are arranged in the hydraulic connection between the first adiabatic cylinder (8) and the second adiabatic cylinder (7). 4. Apparatus according to claim 2 or claim 3, characterized in that the first conduit (1), in which compressed gaseous working fluid flows, via an expansion valve (15) to the second conduit (2) is connected, in which the compressed gaseous working fluid is relaxed. 5. Apparatus according to claim 1 for the relaxation of the gaseous working fluid, characterized in that - the first adiabatic cylinder (108) is connected via a first valve (103) and a three-way valve (120) to a first conduit (101) from which compressed gaseous working fluid can flow into the first adiabatic cylinder (108); the first adiabatic cylinder (108) is connected via a second valve (104) and a three-way valve (119) to a second conduit (102) into which relaxed gaseous working fluid can flow from the first adiabatic cylinder (108); the second adiabatic cylinder (107) is connected via a third valve (106) and the three-way valve (120) to the first conduit (101) from which compressed gaseous working fluid can flow into the second adiabatic cylinder (107); the second adiabatic cylinder (107) is connected via a fourth valve (105) and the three-way valve (119) to the second conduit (102) into which relaxed gaseous working fluid can flow into the second adiabatic cylinder (107); the means for discharging (111) energy is a hydraulic motor (111) which reduces the pressure of the hydraulic fluid passing through the hydraulic motor (111); in which - In the first state and the second state, the valves (103, 104, 105, 106) of the two cylinders (107, 108) are closed; in the first step, in which the hydraulic fluid from the second adiabatic cylinder (107) is guided into the first adiabatic cylinder (108), (i) compressed gaseous working fluid from the first conduit (1) flows into the second adiabatic cylinder (107) via the opened third valve (106), so that the hydraulic fluid is displaced from the second adiabatic cylinder (107) and into the first adiabatic cylinder (108 ) flows; and (ii) relaxed gaseous working fluid from the first adiabatic cylinder (108) flows via the opened second valve (104) into the second conduit (2); in the second step, in which the hydraulic fluid from the first adiabatic cylinder (108) is guided into the second adiabatic cylinder (107), (i) compressed gaseous working medium via the opened first valve (103) into the first adiabatic cylinder (108 ) flows, so that the hydraulic fluid is displaced from the first adiabatic cylinder (108) and flows into the second adiabatic cylinder (107); and (ii) relaxed gaseous working fluid from the second adiabatic cylinder (107) flows via the opened fourth valve (105) into the second conduit (2). 6. Apparatus according to claim 5, characterized in that the flow direction of the hydraulic fluid via three-way valves (9, 10) is determined, which are arranged in the hydraulic connection between the first adiabatic cylinder (8) and the second adiabatic cylinder (7). 7. Apparatus according to claim 4 or claim 5, characterized in that the flow of the compressed gaseous working fluid from the first line (101) to the first adiabatic cylinder (108) or to the second adiabatic cylinder (107) is determined by the three-way valve 20; the flow of the expanded gaseous working fluid from the first adiabatic cylinder (108) or the second adiabatic cylinder (107) into the second conduit (102) is determined by the three-way valve 19. 8. A method for compressing or relaxing a gaseous working fluid by means of a hydraulic fluid in a device comprising a first adiabatic cylinder (8, 108) and a second adiabatic cylinder (7, 107) connected to the first cylinder (8, 108) via a Device for supply (11) or discharge (111) is hydraulically connected by energy, wherein (a) in a first state, the gaseous working fluid is in the first adiabatic cylinder (8, 108) and the hydraulic fluid is in the second adiabatic cylinder (7, 107); (B) in a first step, the hydraulic fluid from the second adiabatic cylinder (7, 107) in the first adiabatic cylinder (8, 108) is guided, wherein the hydraulic fluid passes through the means for supplying (11) or discharge (111) of energy ; (c) in a second state, the gaseous working fluid is in the second adiabatic cylinder (7, 107) and the hydraulic fluid is in the first adiabatic cylinder (8, 108); (D) in a second step, the hydraulic fluid from the first adiabatic Cylinder (8, 108) in the second adiabatic cylinder (7, 107) is guided, wherein the hydraulic fluid passes through the means for supplying (11) or discharge (111) of energy; and (E) the first step (b) upon reaching the second state and then the second step (d) are repeatedly executed upon reaching the first state. 9. The method according to claim 8 for the compression of the gaseous working fluid, characterized in that - The first adiabatic cylinder (8) via a first valve (3) with a first line (1) is connected, can flow into the compressed gaseous working fluid from the first adiabatic cylinder (8); - The first adiabatic cylinder (8) via a second valve (4) with a second Line (2) is connected, can flow from the relaxed gaseous working fluid in the first adiabatic cylinder (8); - The second adiabatic cylinder (7) via a third valve (6) with the first line (1) is connected, can flow into the compressed gaseous working fluid from the second adiabatic cylinder (7); - the second adiabatic cylinder (7) is connected via a fourth valve (5) to the second conduit (2) from which relaxed gaseous working fluid can flow into the second adiabatic cylinder (7); the means for supplying (11) energy is a hydraulic pump (11) which increases the pressure of the hydraulic fluid passing through the hydraulic pump (11); in which - In the first state and the second state, the valves (3, 4, 5, 6) of the two cylinders (7, 8) are closed; in the first step, in which the hydraulic fluid from the second adiabatic cylinder (7) is guided into the first adiabatic cylinder (8), (i) the gaseous working fluid in the first adiabatic cylinder (8) is compressed to a predetermined pressure, wherein, once the gaseous working fluid has reached the predetermined pressure, the first valve (3) opens, so that the compressed gaseous working fluid isobarically flows into the first conduit (1); and (ii) the pressure in the second adiabatic cylinder (7) decreases to a predetermined value, and as soon as the predetermined pressure in the second adiabatic cylinder (7) has been reached, the fourth valve (5) opens, so that expanded gaseous working fluid flows into the second adiabatic cylinder (7); and in the second step, in which the hydraulic fluid is conducted from the first adiabatic cylinder (8) into the second adiabatic cylinder (7), (i) the gaseous working fluid in the second adiabatic cylinder (7) is compressed to a predetermined pressure, wherein, as soon as the gaseous working fluid has reached the predetermined pressure, the third valve (6) opens, so that the compressed gaseous working fluid flows isobarically into the first conduit (1); and (ii) the pressure in the first adiabatic cylinder (8) decreases to a predetermined value, and as soon as the predetermined pressure in the first adiabatic cylinder (8) is reached, the second valve (4) opens so that expanded gas - Shaped working fluid in the first adiabatic cylinder (8) flows. 10. The method according to claim 9, characterized in that the flow direction of the hydraulic fluid via three-way valves (9, 10) is determined, which are arranged in the hydraulic connection between the first adiabatic cylinder (8) and the second adiabatic cylinder (7). 11. The method according to claim 9 or claim 10, characterized in that the first line (1), in which compressed gaseous working fluid flows, is connected via an expansion valve with the second line (2), in which the compressed gaseous working fluid expands becomes. 12. The method according to claim 8 for the relaxation of the gaseous working fluid, characterized in that - the first adiabatic cylinder (108) is connected via a first valve (103) and a three-way valve (120) to a first conduit (101) from which compressed gaseous working fluid can flow into the first adiabatic cylinder (108); the first adiabatic cylinder (108) is connected via a second valve (104) and a three-way valve (119) to a second conduit (102) into which relaxed gaseous working fluid can flow from the first adiabatic cylinder (108); the second adiabatic cylinder (107) via a third valve (106) and the Three-way valve (120) is connected to the first line (101) from which compressed gaseous working fluid in the second adiabatic cylinder (107) can flow; the second adiabatic cylinder (107) via a fourth valve (105) and the Three-way valve (119) is connected to the second line (102), in which relaxed gaseous working fluid in the second adiabatic cylinder (107) can flow; the means for discharging (111) energy is a hydraulic motor (111) which reduces the pressure of the hydraulic fluid passing through the hydraulic motor (111); in which - In the first state and the second state, the valves (103, 104, 105, 106) of the two cylinders (107, 108) are closed; in the first step, in which the hydraulic fluid from the second adiabatic cylinder (107) is guided into the first adiabatic cylinder (108), (i) compressed gaseous working medium via the opened third valve (106) the first conduit (1) flows into the second adiabatic cylinder (107) so that the hydraulic fluid is displaced from the second adiabatic cylinder (107) and flows into the first adiabatic cylinder (108); and (ii) relaxed gaseous working fluid from the first adiabatic cylinder (108) flows into the second conduit (2) via the opened second valve (104); in the second step, in which the hydraulic fluid from the first adiabatic cylinder (108) is guided into the second adiabatic cylinder (107), (i) compressed gaseous working medium via the opened first valve (103) into the first adiabatic cylinder (108 ) flows, so that the hydraulic fluid is displaced from the first adiabatic cylinder (108) and flows into the second adiabatic cylinder (107); and (ii) relaxed gaseous working fluid from the second adiabatic cylinder (107) flows via the opened fourth valve (105) into the second conduit (2). 13. The method according to claim 12, characterized in that the flow direction of the hydraulic fluid via three-way valves (9, 10) is determined, which are arranged in the hydraulic connection between the first adiabatic cylinder (8) and the second adiabatic cylinder (7). 14. The method according to claim 12 or claim 13, characterized in that - the flow of the compressed gaseous working fluid from the first conduit (101) to the first adiabatic cylinder (108) or to the second adiabatic cylinder (107) is determined by the three-way valve 20; the flow of the expanded gaseous working fluid from the first adiabatic cylinder (108) or the second adiabatic cylinder (107) into the second conduit (102) is determined by the three-way valve 19. 15. Device according to one of claims 1 to 7, characterized in that it further comprises at least one three-way valve for determining the flow direction of the hydraulic fluid, which is arranged in the hydraulic connection between the first adiabatic cylinder and the second adiabatic cylinder.