JPS5912181A - Power retrieving device - Google Patents

Abstract

PURPOSE:To improve the retrieving efficiency of energy by a method wherein the retrieving of the energy upon the liquid supplying stroke as well as the pressure reducing stroke of a cylinder for reducing a pressure is permitted in a chemical plant including a process, in which the pressure of high-pressure liquid, containing solid particles and dissolved gas, is reduced. CONSTITUTION:A coal liquidizing plant is equipped with a coal liquidizing product solution supplying line 1, and high-pressure side as well as low-pressure side gas and liquid separating towers 2, 3. In this case, the power retrieving device is consisting of high-pressure liquid pressure reducing plunger type cylinders 11, 14, arranged with plungers 11a, 14a which are opposing mutually, and a double rod type double-acting cylinder 17 for pressure medium, arranged between both cylinders 11, 14 and whose rod ends are connected to the plungers 11a, 14a. Each cylinders 11, 14 are connected in parallel to each gas and liquid separating towers 2, 3, while each cylinder chambers of the double-acting cylinder 17 are connected to a variable volume type main hydraulic pressure motor 20 for retrieving the power and an auxiliary liquid pressure motor 21 through direction switching valves 18, 19, and a generator 24 is connected to a common shaft for these motors.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power recovery device, specifically, a power recovery device, specifically, solid particles and dissolved gas.7. The present invention relates to a device for recovering the pressure energy of the high-pressure liquid as hydraulic power in the process of depressurizing the high-pressure liquid in a chemical plant that includes a process of completely depressurizing the high-pressure liquid contained therein.

The process of fully depressurizing high-pressure liquid is as follows:
Although there are various types in the past, the Unknown Document uses lime liquefaction plants as an example, which have been re-recognized in recent years due to the deterioration of the petroleum situation.
A case will be described in which power is recovered from a high-temperature, high-pressure Ishibushi liquefaction product liquid containing catalyst and other solid particles 2. In this old method liquefaction plant, after crushing and dewatering the lime,
A solvent is added to form a slurry, and this coal slurry is subjected to external pressure,
After preheating, the catalyst 2 and hydrogen are completely added to undergo a liquefaction reaction, and the resulting coal liquefaction product solution is completely separated into gas and liquid, followed by depressurization and fractional distillation.

This depressurization operation is performed by making full use of the throttling effect of the conventional flow rate control valve, which increases the flow rate of the depressurizing liquid. Considering that the valve body 2 and the seat of the control valve are extremely worn out and cannot withstand long-term use, and that the pressure energy of the liquid coal product/WM is dissipated as heat energy, we have decided to use that energy as power. A device to collect? , for example, was proposed in Japanese Patent Application No. 108365/1983. This power recovery device is driven by a high-pressure liquid, and has a high-pressure liquid depressurization cylinder that depressurizes and discharges the inflowing high-pressure liquid, and a high-pressure liquid depressurization cylinder that is connected and driven to the depressurization cylinder to suck in a pressure medium, increase the pressure, and discharge it. A cylinder for pressure medium which discharges the pressure energy of the pressure medium discharged from the accumulator and an accumulator disposed in the pressure medium return passage from the discharge port 1 of the cylinder for pressure medium to the pressure medium tank. It is characterized by consisting of an actuator that converts it into mechanical energy. This power recovery device converts the pressure energy of the high-pressure liquid into energy to be transported to a pressure medium tank during the liquid supply stroke of the decompression cylinder, and then drives the hydraulic motor tray to recover the power. It is impossible to recover the energy of time, and the power recovery efficiency is 1.
There was a problem in that the pressure energy of the high pressure liquid at the end of the liquid supply stroke of the pressure reduction cylinder was discharged from the pressure reduction liquid discharge valve at high speed, causing wear on the valve and valve seat due to solid particles in the liquid. .

The present invention has been made in view of these problems, and aims to provide a power recovery device having a highly efficient and durable supply/discharge valve system. A liquid pressure reduction cylinder and a pressure medium cylinder are arranged facing each other, and the high pressure liquid pressure reduction cylinders are connected to a high pressure liquid supply source 2 and a pressure reduction liquid receiving valley via a high pressure liquid supply-Jf and a pressure reduction liquid discharge valve, respectively. On the other hand, each cylinder chamber of the pressure line cutter cylinder is connected to a main hydraulic motor for power recovery equipped with 8 flow control functions through a direction changer. , the cylinder chamber of the pressure medium cylinder is connected to the auxiliary hydraulic motor for power recovery via the directional switching valve, and the directional switching valve is fully valved to control the switching valve during the pressure reduction stroke of the pressure medium cylinder. A power recovery device, characterized in that the hydraulic motor is driven through the movement of the pressure medium cylinder by operation;
It is in.

A detailed explanation will be given below with reference to the attached drawings.

Figure 1 shows an example in which the uninvented power recovery device is applied to the depressurization process of an old method liquefaction plant.The operation of the power recovery unit is the same, so to explain Figure 1, 1 is a coal liquefaction product solution supply. 2 is a high-pressure gas-liquid separation tower, 3 is a low-pressure gas-liquid separation tower, and a power recovery device is installed between the low-pressure gas-liquid separation tower 3 and the high-pressure gas-liquid separation tower 2. There is. 2.4 is an emergency pressure reducing valve, which is kept closed at all times. The illustrated power recovery device includes plunger-type cylinders 11.14 for depressurizing high-pressure liquid arranged with plungers 141 facing each other, and a plunger-shaped cylinder 11.14 arranged between both cylinders, with a valley rod end connected to each of the plungers. A double-rod type double-acting cylinder 17 for pressure medium and a cylinder for pressure reduction 11.1.
4 are connected in parallel to the high-pressure side gas-liquid separation tower 2P and the low-pressure side gas-liquid separation tower 3 via the high-pressure side supply valve 12.15s and the reduced pressure liquid discharge valve 13.16, respectively. Each cylinder chamber of the pressure medium tank cylinder 17 is equipped with a directional control valve 18°19.
It is connected to a variable displacement main hydraulic motor 20 for power recovery through the capacitor, and is also connected to an auxiliary hydraulic motor 21 through the power recovery variable displacement main hydraulic motor 20 . A hydraulic pump 28 is connected coaxially to the auxiliary hydraulic motor 21, and the main hydraulic motor 20 and the auxiliary hydraulic motor 21
A generator 24 is coaxially connected to the generator 24 . 25.26.3
6.37 is a check valve.

As shown in FIG. 2, the power recovery device having the above configuration has the following features:
A liquid supply stroke (state A->B) that supplies high-pressure liquid to the cylinder 11.14, a depressurization stroke that reduces the pressure of all the high-pressure liquid in the cylinder to a predetermined pressure (state B + C), and Drainage process of discharging the reduced pressure liquid to the valley (state C-+D
), has an operation cycle consisting of four strokes, including an external pressure stroke (state D - + A) in which the pressure of the residual liquid in the cylinder is increased to the original high pressure in a trench, and is operated as follows.

In FIG. 1, the pressure reducing cylinder 11 has completed its pressure reducing stroke, the pressure reducing cylinder 14 has completed its entire external pressure stroke, and the valve 12.
13.1.5.16 is in closed state, switching: *18,1
．． 9. Assuming that the valves 13 and 27 are in the neutral position, first, the pressure reducing liquid discharge valve 13. At the same time as h and high pressure liquid supply valve 15 are opened, switching valve 18 is switched to the first position on the left side of the figure, and the supply sf stroke of cylinder 14 to cylinder 1 is switched to the first position on the left in the figure.
The first draining step is started. Together with the plungers 11a, ], 4a of both cylinders 11.14, the stepped cylinder 17
Since the piston 17a moves to the left, the pressure medium in the left cylinder chamber is completely supplied to the main hydraulic motor 20 through the switching valve 18, and the motor 20 is fully driven.
4, the pressure energy of the coal liquefaction product solution is recovered. In the figure, energy recovered as power for driving 20 main hydraulic motors is converted into electrical energy by a generator 24 connected to the motors. On the other hand, low-pressure pressure medium is supplied to the right cylinder chamber of the double-acting cylinder 17 via the check valve 25 . The main hydraulic motor is a variable displacement hydraulic motor, and the capacity of the hydraulic motor is controlled to keep the liquid level constant based on a signal from the sensor 5 that detects the liquid level tray of the high-pressure side gas-liquid separation tower 2. In other words, since the flow rate of the pressure medium flowing through the main hydraulic motor 20 is controlled, the flow rate of the coal liquefaction product solution is controlled.

In this way, when the liquid supply stroke of the cylinder 14 is completed, the switching valve 18 is returned to the neutral position, and the high pressure liquid supply valve 15 is returned to the neutral position.
is closed, then the switching valve 18 is switched to the second position, the depressurization stroke of the cylinder 14 is started by the expansion action of the dissolved gaff in the coal liquefaction product solution in the cylinder 14, and the left side of the double-acting cylinder 17 is opened. The pressure medium in the cylinder chamber is supplied to the auxiliary hydraulic motor 21 through the switching valve 18, and all of the energy during the pressure reduction process is converted into electrical energy by the generator 24 connected to the auxiliary hydraulic motor 21 for power recovery. .

During the depressurization stroke of the cylinder 14, the decompression liquid discharge valve 1
3 is closed, the switching valve 19 is switched to the neutral position, the switching valve 27 is switched to the second position on the right side of the figure, and the external pressure stroke of the cylinder 11 is started by the pressure medium of the hydraulic pump 28Z+- etc. When the external pressure stroke ends and the pressure reduction stroke of the cylinder 14 ends, the switching valve 27 is returned to the neutral position, which is the opposite state to the above-mentioned initial state. That is, when the high-pressure liquid supply valve 12 and the pressure-reducing liquid discharge valve 16 are opened and the switching valve 19 is switched to the first position, the cylinder 11 performs the liquid supply stroke and the cylinder 14 performs the liquid discharge stroke in the same manner as in the previous case. Perform and repeat the same exercise.

Although the apparatus shown in FIG. 1 uses a pair of cylinders 11 and 14, it is also possible to connect two or three pairs of cylinders in parallel to control the pulsation of the coal liquefaction product solution. Further, in this case, the hydraulic pump 28 becomes unnecessary, and may be connected to the A-boat tray main recovery line flow path of the switching valve 27.

As explained above, the device of the present invention recovers the energy during the depressurization stroke in addition to the energy during the liquid supply stroke of the decompression cylinder, and performs the external pressure stroke with a part of the power recovered in the depressurization stroke. As a result, the recovery efficiency 2 can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing one embodiment of the power recovery device of the present invention, and FIG. 2 is an acupressure diagram showing its operating cycle. 11.14...Cylinder for high pressure liquid pressure reduction, 17...
・Double rod type double acting cylinder, 18.19.27...
・Switching valve, 20... Main hydraulic motor for power recovery, 2
1... Auxiliary hydraulic motor for side force recovery, 24... Generator, 28... Hydraulic pump, 34... Turf,
35...Suction filter.

Claims (1)

[Claims] (1) At least one pair of high-pressure liquid pressure reduction cylinders and a pressure medium cylinder are disposed facing each other, and the high-pressure liquid is supplied through seven high-pressure liquid pressure reduction cylinders and a high-pressure liquid supply valve and a pressure-reduction liquid discharge valve. In a power recovery device, each cylinder chamber of the pressure medium cylinder is connected to a main hydraulic motor for power recovery which performs all flow control functions via a directional control valve. , is connected to an auxiliary hydraulic motor for recovering all the power in the cylinder chamber of the pressure medium cylinder through the direction switching tray, and operates the switching valve during the pressure reduction stroke of the pressure medium cylinder through the direction switching tray. A power recovery device characterized in that the hydraulic motor is fully driven through the movement of the pressure medium cylinder.