RU2126940C1 - Device for control of supply and discharge of gases from accumulating reservoirs - Google Patents

Abstract

FIELD: gas mixture separating plants; gas chemical and other industries where separation of gas mixture under pressure is required. SUBSTANCE: device includes positive fittings mounted in pressure relieving and pressure raising line; these fittings are connected with reservoir change-over device. Fitting is made in form of three-way positive valve; change-over device is made in form of lever-type selector. Each accumulating reservoir is provided with rod connected with lever-type selector and mounted along of reservoir with metal "float" sliding over it. Metal "float" is immersed in liquid product by 1/3 of volume. Rod is provided with upper shut-off limiter and lower limiter. EFFECT: simplified construction. 1 dwg

Description

 The invention relates to installations for the separation of gas mixtures and can be used in gas, chemical and other industries using products of separation of gas mixtures under pressure.

 A device for the gasification of liquefied products (Glizmanenko D. L. "Obtaining oxygen", 1972, S. 213 - 214), providing for the supply of liquefied gas to the regenerator coil with a plunger pump under pressure, evaporation in the coil due to heat exchange by the oncoming warm air stream going through the annular space of the regenerator and the issuance of a warm gaseous product under pressure from the air separation unit. Moreover, for the supply of technological gas to the consumer, additional compression of the gas in the compressors is necessary. The device includes a regenerator of the air separation unit with coils, a plunger pump with an electric motor, pipelines for supplying liquefied gas to the pump and from the pump to the regenerator, a means of creating an increased pressure of the process gas supplied to the consumer in the form of compressor units.

 The closest technical solution to the proposed one is a device for gasification of liquefied products (Patent for the invention of the Russian Federation N 2046260 "Method for producing gaseous products of separation of air under pressure and a device for producing gaseous products of separation of air" dated October 20, 1995, class F 17 D 1 / 07), which provides for the supply of liquefied gas to the regenerator coil with the help of two alternately working storage tanks, into which the liquid product by gravity enters the filling, and is discharged from them into the coil under excess chnym pressure up to 200 atm. Alternately switching storage tanks from the accumulation mode to the liquid product delivery mode and vice versa, i.e. regulation of gas supply and delivery is provided by a command-executive mechanism (CMM), which provides signals for switching forced valves installed on the pressure supply and pressure relief lines from storage tanks. A disadvantage of the known technical solution is the presence of a complex command-executive mechanism, which through the actuators switches the forced-action valves.

 The technical result of the invention is to simplify the design of the device for regulating the supply and delivery of gas (switching device), due to the exclusion from the installation scheme of the command-actuator mechanism and the replacement of the inlet and outlet valves on each storage tank with one direct-acting three-way forced valve.

 This is achieved by the fact that the forced fittings are made in the form of a direct-acting three-way forced valve, and the switching means is made in the form of a lever switch, while each of the two storage tanks is equipped with a rod connected to the lever switch and passing along the tank axis, as well as sliding along it metal "float" immersed in a liquid product in 1/3 of the volume. Moreover, the rod is equipped with upper locking and lower limiters.

 Thus, the regulation of the supply and delivery of gas from storage tanks is carried out using the lever switch three-way valves. The switch is switched depending on the level of the liquid product in the storage tanks. When one of the containers is completely empty from the liquid, the lever switch, and therefore the storage tank, switches from the mode of dispensing the product under pressure to the filling mode, and the second storage tank switches from the filling mode to the mode of dispensing of the product under pressure. When the storage tank is completely filled with liquid, it is shut off to prevent overfilling with the liquid product.

 When emptying the tank, the “float”, sliding along the rod, falls down and rests its weight on the rod limiter, forcing it to move and switch the lever switch through flexible connection. The switch, acting directly on the stem of the three-way forced valve, switches it, as a result of which the empty storage tank becomes in the liquid product filling mode, and the second storage tank, as a result of switching the second three-way valve, becomes in the mode of dispensing the liquid product under pressure to the consumer . When the liquid product is completely squeezed out in the second container under the action of the weight of the “float” that has fallen, the modes will reverse (via the lever switch and the three-way valve) of the storage tanks to the opposite.

 To prevent overfilling of storage tanks with a liquid product, the rod is designed so that when the tank is full, the “float” abuts against the upper limiter of the rod, which at the same time is a plug that, when rising, closes the gas pressure outlet, preventing further filling of the storage tank with liquid product. Moving the rod to close the pressure relief hole does not affect the position of the lever switch and occurs only due to the ascent of the "float" and the movement of the rod without affecting the lever switch.

 Maintaining the desired pressure of the produced liquid product is carried out by the known design of the control valve installed on a common line after the check valves for the issuance of the liquid product under pressure in the evaporator coil. The degree of opening of the control valve and, consequently, the capacity of the installation for the product being discharged under a given pressure is related to the pressure in the gaseous product system after the evaporator, i.e. consumer. If the withdrawal of the gaseous product ceases, then the pressure in the system rises and the control valve closes until it is completely closed. Installation automatically stops in the intermediate position. If, after a break, the consumer begins to pick up the gaseous product, the gas pressure in the system starts to drop and the control valve, trying to maintain the set pressure, starts to open slightly, the greater the gas consumption by the consumer. Improving the design of the installation of the prototype regarding the switching device of the storage tanks, as well as the presence of a control valve operating from a given pressure, automate the entire process of the installation.

The device allows you to:
abandon the automation system - command-executive mechanism;
abandon servos on forced action valves;
Replace the four pressure relief valves with two direct acting three-way valves.

 Comparison of the claimed device with the prior art shows that the invention is "new", meets the eligibility conditions of "inventive step" and "industrial applicability".

 The drawing shows a kinematic diagram of the installation using a device for regulating the supply and delivery of gas in the form of a lever switching device of three-way valves.

 The device contains 1 and 2 - liquid product storage tanks, 3 - liquid product evaporator-heat exchanger or air separation unit regenerators, 4 and 5 - direct-acting three-way forced valves located on pressure and pressure relief lines from storage tanks, 6 - lever switch of three-way valves, 7 and 8 - "floats" sliding along the rods, 9 and 10 rods with upper shut-off and lower limiters, 11, 12 - non-return automatic valves on the lines of liquid product supply to storage tanks, 13 and 14 - arr. automatic automatic valves on the lines for dispensing a liquid product under pressure through a 15 — control (pressure reducing) valve to the evaporator-heat exchanger, 16 — a valve for supplying liquid to the tanks, 17 — a valve for dispensing a gaseous product under pressure from the evaporator.

 A device for producing gaseous products under a given pressure with a lever switch is an autonomous installation in a separate insulated casing, to which a liquefied product is supplied under an overpressure of 0.3 - 1.0 atm, and a predetermined pressure is provided at the outlet of the installation (up to 200 atm ) due to the use of latent (internal) energy of liquefied gas and working automatically from the gas pressure in the consumer system.

 The device operates as follows. According to the invention, if the liquid level in the storage tank 1 drops to a minimum, then the "float" 7, sliding along the guide rod 9 under its own weight, abuts against the lower limiter of the rod 9 and forces it to move down, which simultaneously pulls the lever 6 of the mechanism switching, forcing it to rotate on an axis. In this case, the lever mechanism 6 causes the three-way valves to be switched through the stem in such a way that the 3-way valve 4 connects the internal cavity of the storage tank with the atmosphere (or returns the gaseous product to an air separation unit for disposal with a pressure close to atmospheric) and simultaneously closes the hole supply of the set gas pressure to the tank. Through the valve 16 and the automatic check valve 11, a liquid product under an overpressure of 0.3 - 1.0 atm begins to flow to fill the tank 1. As the tank 1 is filled with liquid, the "float" pops up and abuts against the upper stop limiter, moving the rod up to full closing the gas vent through which the rod passes. In this position, the filled tank 1 is an indefinite time in anticipation of switching containers from the lever switching mechanism. The operation of the switching mechanism 6 occurs only when one of the containers is completely emptied from the liquid product under the influence of weight on the rod "float".

 In the second storage tank 2 at this time, after switching, the 3-way valve 5 connects the internal cavity of the tank 2 with a predetermined pressure of the gas going to the consumer after the evaporator-heat exchanger 3, and simultaneously closes the pipeline for dumping gas pressure into the atmosphere. The liquid product in the tank 2 under the action of a hydrostatic column of liquid, through the automatic check valve 14 and the pressure reducing valve 15, enters the evaporator-heat exchanger 3 located below the storage tanks 1, 2, where it is gasified and passes through the valve 17 under the set pressure to the consumer. As the storage tank 2 is emptied, the “float” drops, and when the tank 2 is completely empty, the weight of the “float” switches the lever switch of the 3-way valves through the rod. In this case, the container that was on the filling becomes the extrusion of the liquid product under pressure, and the container that was on the extrusion of the product becomes the filling of the liquid product. Thus, there is a switching of storage tanks on a certain cycle in automatic mode. If the selection of the gaseous product under pressure after the evaporator increases, the switching cycle of the storage tanks decreases, and vice versa, if the selection of the product under pressure decreases, the switching cycle increases until it stops completely until the set pressure in the consumer system begins to drop.

 Thus, in the proposed technical solution, the use of the lever switch of the 3-way valves of the storage tanks of the installation for the production of gaseous products under pressure (RF patent N 2046260) allows you to automate the operation of the installation from zero capacity to the maximum design for the delivery of liquefied products at a given pressure in depending on the gas pressure in the consumer system, structurally simplify the valve switching mechanism, ensure high reliability in operation, improve operation Noe service.

Claims (1)

 A device for controlling the supply and delivery of gas from storage tanks, mainly during gasification of liquefied gases, including forced fittings installed on the pressure relief and pressure lines in the tanks, connected with the tank switching means, characterized in that the forced fittings are designed as a three-way direct pressure valve and the switching means is made in the form of a lever switch, with each of the two storage tanks equipped with a rod associated with the lever m switch and passing along the axis of the tank, as well as a metallic “float” sliding along it, immersed in the liquid product to 1/3 of the volume, and the rod is equipped with an upper stop and lower limiters.