CN203173832U - Power-driven steam pipeline network for synthesis process of ammonia synthesis device - Google Patents

Abstract

The utility model provides a power-driven steam pipeline network for the synthesis process of an ammonia synthesis device. The power-driven steam pipeline network comprises a power-driven steam main pipeline network formed by a thermal coupling steam supply pipeline network, an ammonia plant air separation medium steam pumping pipeline network and a waste heat boiler byproduct steam pipeline network, and a steam silencer of the power-driven steam main pipeline network, wherein the waste heat boiler byproduct steam pipeline network is connected with the ammonia plant air separation medium steam pumping pipeline network by an outlet valve; and a pressure regulation valve is arranged on the power-driven steam main pipeline network arranged at an inlet end of the thermal coupling steam supply pipeline network. The power-driven steam pipeline network guarantees the whole device to reach or even exceed the production capacity of the original design and can rapidly balance the pressure stability of the power-driven steam main pipeline network of the ammonia synthesis device, thus accelerating the stream grid connection speed, winning the time, reducing the steam waste and greatly improving the economic benefit.

Description

A power-driven steam pipe network in the synthesis process of a synthetic ammonia plant

technical field

The utility model relates to the technical field of processing equipment, in particular to a power-driven steam pipe network in the synthesis process of an ammonia synthesis device. the

Background technique

At present, the two centrifugal compressor units in the synthesis process of the 300,000-ton annual synthetic ammonia plant are driven by medium-pressure superheated power steam, one is a synthesis gas compressor unit, and the other is an ammonia compression refrigeration unit. The operating pressure is 3.82MP(G). During production under full load conditions, in order to meet the demand for power steam for the normal production of the two major compressor units, to achieve the design level of the 1,000-ton daily output of the ammonia synthesis unit, and to achieve high efficiency and energy saving, the steam consumption of the two major units must be guaranteed Up to 66T/h. At present, the medium-pressure power steam consumed by the two units is jointly provided by cogeneration, ammonia plant air separation pumping and superheated steam by-product of the 4.0MPa waste heat boiler in the synthesis control circuit. the

According to the existing design of the power-driven steam pipe network, the normal supply of power steam pressure and the speed of the synthesis control loop 4.0MPa waste heat boiler by-product steam connected to the grid are restricted during the full-load production of the combined two centrifugal compressor units, which greatly affects the System loading time, and there are great safety hazards and waste of resources during the time when waste heat boiler by-product steam is connected to the grid, the details are as follows: 

1. Since all medium-pressure superheated steam pipe networks in the production area are interconnected, and there are many steam users, the pressure of the steam pipe network from the cogeneration outlet is far below the full-load operation of the two compressor units in the ammonia plant When the guaranteed value is 3.82MPa (G), thus seriously restricting the working efficiency of the two major units, that is to say, restricting the design capacity of 1,000 tons of ammonia synthesis plant per day;

2. Due to the long steam pipeline (nearly 200 meters) between the steam outlet pressure regulating valve of the waste heat boiler and the steam inlet of the ammonia ice machine, before the steam parameters are qualified and connected to the grid, the steam in this long pipeline is in a non-flowing state, that is, in a static state. There are long dead ends in the pipeline, so the steam temperature will gradually decrease with time. When the qualified high-temperature steam produced by the waste heat boiler is incorporated into the pipe network, a certain temperature difference will be generated due to the mixture of cold and hot gases, which will reduce the temperature of the grid-connected steam and form a large amount of steam condensate. At this time, if the grid connection speed is too fast, it will directly affect the steam inlet temperature of the steam turbine of the ammonia ice machine, because the steam inlet of the ammonia ice machine is closest to it, and even cause a liquid-carrying accident of the unit. Therefore, in order to ensure the safe operation of the unit, the speed of steam grid connection was delayed by about 2 to 3 hours. Simultaneously, a large amount of its steam is controlled to enter the muffler to be vented through the vent regulating valve at the steam outlet of the waste heat boiler, which is wasted.

Utility model content

The purpose of this utility model is to solve the above-mentioned deficiencies, provide a power-driven steam pipe network for the synthesis process of the ammonia synthesis plant, and solve the problem that the steam pressure of the two major compressor units in the synthesis process of the ammonia synthesis plant cannot meet the design requirements when they are fully loaded. The maximum working efficiency of the two units enables the synthetic ammonia plant to reach a daily output of more than 1,000 tons; solves the speed of the by-product steam of the synthetic waste heat boiler to be connected to the grid, shortens the system load time, ensures the safe operation of the unit when the steam is connected to the grid, and reduces the waste of by-product steam . the

In order to achieve the above effects, the utility model provides a power-driven steam pipe network for the synthesis process of an ammonia synthesis device, including a steam pipe network for combined heat supply, a steam pipe network for air separation in an ammonia plant, and a waste heat boiler by-product steam pipe network. The power-driven steam main pipe network and the steam muffler of the power-driven steam main pipe network, the by-product steam pipe network of the waste heat boiler is connected to the ammonia plant air separation extraction steam pipe network through the outlet valve; A pressure regulating valve is arranged on the power-driven steam main network at the network inlet. the

Because the waste heat boiler in the synthesis circuit can produce about 39 T/h of 4.0 MPa steam under full load, and the air separation pump can provide about 40 T/h of 4.0 MPa steam to the steam pipe network per hour under normal conditions. It can provide contract 80T/h power steam to the steam pipeline network, far meeting the steam consumption of 66 T/h required by the two major units operating under full load conditions. Therefore, as long as the steam volume of about 80T/h provided by the synthesis waste heat boiler and the air separation extraction is fully and rationally utilized, it is sufficient to ensure the steam pressure in the power-driven steam main pipe network of the synthesis process of the ammonia plant. the

The novel pressure regulating valve of the present invention can regulate the stability of the steam pressure in the steam main pipe network driven by the power of the synthesis process of the ammonia synthesis device. At the beginning of the start-up of the unit, due to the light load of the entire system, the pressure regulating valve is open, and the by-product steam pipe network of the waste heat boiler has not yet been merged into the main steam pipe network. The steam pipe network and the ammonia plant air separation extraction steam pipe network are provided. When the by-product steam pipe network of the waste heat boiler is incorporated into the power-driven steam main pipe network, the pressure regulating valve can be slowly closed, that is, the cogeneration steam pipe network is closed. The power-driven steam main pipe network is isolated from other steam users in the factory, the pressure of the power-driven steam main pipe network of the two major units in the synthesis process of the ammonia synthesis device is increased, and the steam volume provided by the air separation pumping and waste heat boiler is effectively used to meet the requirements of the utility model The power-driven steam main pipe network pressure reaches the unit design requirement of 3.80MPa (G), so as to ensure the process conditions when the unit is in full-load production, so that the device can fully meet the production design capacity. the

A bypass valve is connected in parallel with both ends of the pressure regulating valve. the

The bypass valve connected in parallel with both ends of the pressure regulating valve is kept slightly open during daily production to form a small flow of steam to keep the pipeline from generating steam condensation dead angle. ), and by controlling the pressure regulating valve, the cogeneration steam can quickly enter the power-driven steam main pipe network, balance the stability of the main pipe network pressure, and ensure the steam consumption of the two major units at light load; at the same time, avoid the introduction of steam condensate The possibility of accidents caused by the crew. the

A heating pipe venting valve is provided at the junction of the by-product steam pipe network of the waste heat boiler and the steam extraction pipe network of the ammonia plant air separation, and the outlet end of the warm pipe venting valve is connected to the inlet end of the steam muffler. the

From the steam inlet of the ammonia compression refrigerating unit in the synthesis process of the ammonia synthesis unit to the end of the steam main pipe network of the utility model, the pipe is preheated and discharged in advance to increase the temperature of the steam in the dead corner of the pipe, so that it can meet the operation requirements, and it is convenient for the by-product steam of the waste heat boiler to be quickly discharged. The speed of steam grid connection is shortened from 2 to 3 hours to less than 1 hour, which greatly improves the speed and time of steam grid connection, and effectively solves the safety hazards caused by steam grid connection to the unit; at the same time, it is well It avoids the waste of a large amount of qualified by-product steam due to the long time of steam grid connection, and strives for effective time for the system to enter the full load state as soon as possible. the

In summary, the utility model has the following beneficial effects:

1. The design of the process pipeline is simple and convenient for modification.

2. The investment is small, the operation is simple, the return is high, the production capacity of the device is greatly improved, and the practical effect is remarkable. the

3. Effectively solve the problem of insufficient steam pressure when the two major units are running at full load and fail to meet the design requirements, fully ensuring that the entire device reaches or even exceeds the original design production capacity. the

4. In the event of an accident, it can quickly balance the pressure of the power-driven steam main pipe network of the ammonia synthesis plant and stabilize it. the

5. Effectively solve the potential safety hazards when steam is connected to the grid, speed up the speed of steam connection to the grid, save time, reduce steam waste, and greatly improve economic benefits. the

4. By using the original muffler, the noise pollution when the steam is vented is solved, the investment is reduced, and the high efficiency, energy saving, cleanliness and environmental protection are realized. the

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment, the utility model is described in further detail. the

Fig. 1 is a structural representation of the utility model;

In the figure: 1-Heat cogeneration steam pipe network, 2-Pressure regulating valve, 3-Ammonia plant air separation extraction steam pipe network, 4-Synthesis gas compressor unit, 5-Outlet valve, 6-Waste heat boiler by-product steam pipe Net, 7-steam muffler, 8-heat pipe vent valve, 9-ammonia compression refrigeration unit, 10-bypass valve.

Detailed ways

As shown in Figure 1, a power-driven steam pipe network for the synthesis process of an ammonia synthesis plant includes a steam pipe network 1 for combined heat supply, a steam pipe network 3 for air separation in an ammonia plant, and a waste heat boiler by-product steam pipe network 6. The power-driven steam main pipe network, the driving steam for the syngas compressor unit 4 and the ammonia compression refrigeration unit 9 in the synthesis process of the ammonia synthesis plant, and the steam muffler 7 of the power-driven steam main pipe network; the waste heat boiler by-product steam pipe network 6 It is connected to the steam extraction pipe network 3 in the air separation of the ammonia plant through the outlet valve 5; the power-driven steam main pipe network located at the inlet end of the heat combined steam supply pipe network 1 is provided with a pressure regulating valve 2, and a bypass is connected in parallel at both ends of the pressure regulating valve 2 valve 10. The joint of waste heat boiler by-product steam pipe network 6 and ammonia plant air separation steam extraction pipe network 3 is provided with warm pipe vent valve 8, and the outlet end of warm pipe vent valve 8 is connected to the inlet end of steam muffler 7 . the

The pressure regulating valve of the utility model can regulate the stability of the steam pressure in the main steam pipe network driven by the power of the synthesis process of the ammonia synthesis device. At the beginning of the start-up of the unit, the pressure regulating valve is in the open state, and the power steam required by the two major units in the system is provided by the combined heat supply steam pipe network and the ammonia plant air separation extraction steam pipe network. When the waste heat boiler by-product steam pipe network is integrated into the power-driven steam main pipe network, the pressure regulating valve can be slowly closed, that is, the heat cogeneration steam pipe network is closed, and the steam volume provided by the air separation and waste heat boiler is effectively used. Satisfying the pressure of the power-driven steam main pipe network of the utility model reaches the unit design requirement of 3.80MPa (G), so as to ensure the process conditions when the unit is in full-load production, so that the device can fully meet the production design capacity. In addition, the bypass valve connected in parallel with both ends of the pressure regulating valve is kept slightly open during daily production to form a small flow of steam to keep the pipeline from generating steam condensation dead angle. Vehicles, etc.), and by controlling the pressure regulating valve, the cogeneration steam can quickly enter the power-driven steam main pipe network, balance the stability of the main pipe network pressure, and ensure the steam consumption of the two major units at light load; at the same time, avoid steam condensate Bringing into the unit may cause accidents. the

From the steam inlet of the ammonia compression refrigeration unit to the end of the steam main pipe network of the utility model, the pipeline is preheated and discharged in advance, and the steam temperature in the dead corner of the pipeline is increased to make it meet the operation requirements, which facilitates the rapid integration of the by-product steam of the waste heat boiler into the steam main pipe network, and the steam is merged into the main pipe network. The network speed is shortened from 2 to 3 hours to less than 1 hour, greatly improving the speed and time of steam grid connection, effectively solving the safety hazards caused by steam grid connection; If it is too long, a large amount of qualified by-product steam is discharged and wasted, which buys effective time for the system to enter the full load state as soon as possible. the

The above embodiments are not limited to the protection scope of the present utility model, and all modifications or variations based on the basic idea of the present utility model belong to the protection scope of the present utility model. the

Claims (3)

1. the power wheel drive steam pipe system of a synthetic ammonia installation synthesis procedure, comprise the power wheel drive steam manifold net of being formed by steam pumping pipe network and waste heat boiler byproduct steam pipe network in hot alliance steam pipe system, the empty branch of ammonia factory, and the steam silencer of power wheel drive steam manifold net, it is characterized in that: the steam pumping pipe network was connected during described waste heat boiler byproduct steam pipe network divided with described ammonia factory is empty by outlet valve; The power wheel drive steam manifold that is positioned at hot alliance steam pipe system inlet end is provided with pressure regulator valve on the net.

2. the power wheel drive steam pipe system of a kind of synthetic ammonia installation synthesis procedure according to claim 1 is characterized in that: the two ends of described pressure regulator valve by-pass valve in parallel.

3. the power wheel drive steam pipe system of a kind of synthetic ammonia installation synthesis procedure according to claim 1, it is characterized in that: the junction of steam pumping pipe network is provided with the heating coil blow-off valve in the empty branch of described waste heat boiler byproduct steam pipe network and ammonia factory, and the exit end of described heating coil blow-off valve is connected with the inlet end of described steam silencer.

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