RU2507438C1 - Injector for cryogenic liquid - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: cryogenic liquid injector includes a cryogenic liquid inlet assembly, a cryoreservoir and a cryogenic liquid outlet assembly. The inlet assembly includes a nozzle with an external thread, which has a channel along the axis, which is connected through a capillary to a compressed gas bottle, a transition branch pipe with a thread on inner surface for screwing of the nozzle and with through axisymmetrical holes; with that, the nozzle can have two positions: a) holes are covered and cryogenic liquid does not enter the cryoreservoir; b) holes are open and cryogenic liquid enters the cryoreservoir, and a pipeline attaching the inlet assembly to the cryoreservoir. The outlet assembly includes a discharge pipeline with a coupling and a flange with a membrane in the form of a disc, which is pressed to the outlet hole of the cryoreservoir by means of a washer plate, the inner diameter of which is chosen depending on the value of pressure required for membrane rupture, and a hold-down nut. Helium or liquid nitrogen is used as compressed gas. Liquid methane is used as cryogenic liquid.

EFFECT: intensifying a hydrate formation process.

6 cl, 2 dwg

Description

The invention relates to the field of cryogenic and vacuum technology and relates to devices for dosed dispensing of cryogenic liquid into technological zones with high and ultrahigh pressure. The invention can be applied where a single sharp decrease in temperature and the creation of pressure in a closed volume of liquid is necessary, in particular in the food, chemical industry, and medicine.

The prior art devices for the metered supply of cryogenic liquid in a sealed container to create a safe inert atmosphere and pressure after sealing [RU 2374555, 04/14/2005, F17C 9/00; US 5385025, 1994.03.04, B65B 31/00; F17C 13/02; FR 2688469, 1992.03.16, B65B 31/00; F17C 9/00 and others], which are analogues of the proposed device.

A device is known [US 5385025, 1994.03.04, BV 31/00; F17C 13/02] for dosed delivery of cryogenic liquid, including a vessel for cryogenic liquid, a block with a concentric hole, the diameter of which is adjustable, mounted on the bottom of the vessel, and a gas supply pipe for organizing discrete flow of cryogenic liquid from the vessel. The specified invention provides a productivity of about 200-500 sealed containers per minute.

A device for the dosed dispensing of cryogenic liquid [RU 2374555, 04/14/2005, F17C 9/00], comprising a vessel for cryogenic liquid with a filling and leveling valve and a fitting for removing steam, and a dispenser including a valve with a controlled drive and a cylinder with input holes, as well as a saddle with an outlet nozzle, the inlet of the cylinder is in communication with the cavity of the vessel for cryogenic liquid using a pipe for supplying cryogenic liquid and a channel for lifting the vapor-liquid mixture.

The main problem to be solved in these inventions is the provision of reliable dosing of equal volumes of cryogenic liquid, including for dropping dosing of cryogenic liquid. It is especially advisable to use them for a droplet dosed supply of liquid nitrogen into sealed containers moved by a conveyor, for example bottles, cans, bags, etc., to create a safe inert atmosphere and excess pressure after sealing (clogging) these containers.

In known dispensers, pressure is not used to supply cryogenic liquid, cryogenic liquid drains by gravity. Dosage is carried out by automatically supplying a stream of gas, which cuts the flow of cryogenic liquid.

In these devices, it is impossible to implement the conditions for obtaining gas hydrates.

The basis of the present invention is the creation of a device for the metered supply of cryogenic liquid under pressure to a high-pressure zone to initiate a thermal explosion (explosive boiling), accompanied by significant shock waves, in order to obtain the conditions necessary to intensify the hydrate formation process.

The proposed device is based on the use of the phenomenon of explosive boiling of cryogenic liquid, accompanied by a significant hydraulic shock (shock waves) with pressure (with pressure surges) up to 50 atmospheres.

The problem is solved by the fact that in the injector for cryogenic liquid, including the cryogenic liquid input unit, the cryogenic tank and the cryogenic liquid output unit, according to the invention, the input unit includes an external threaded fitting having an axis along the channel connected by a capillary to a compressed gas cylinder which is supplied under pressure from 10 to 100 atmospheres, transition pipe with thread on the inner surface for screwing in the fitting and with through axisymmetric openings for supplying cryogenic liquid, located opposite each other ha one axis intersecting the axis of the nozzle at an angle of 90 degrees, the nozzle may have two positions: a) the opening is blocked by the bore axis and the cryogenic liquid does not flow into kriorezervuar; b) the holes 3 and the hole along the channel axis are open and the cryogenic liquid enters the cryo-tank, and the pipeline connecting the input unit to the cryo-tank, which has the shape of a cylinder with conical bottoms. In the injector for cryogenic liquid according to the invention, the outlet assembly includes a waste pipe with a pipe length optimization sleeve and a flange with a membrane in the form of a thin foil disk, which is pressed against the cryo-tank outlet by a washer, the inner diameter of which is selected depending on the pressure required to rupture the membrane , and clamping nut. The geometric parameters of the pipeline, the discharge pipe and the cryo-tank are selected from the conditions of minimum heat loss and the strength conditions when the pressure inside the pipelines and cryo-tank changes up to 600 atmospheres. All parts of the injector are thermally insulated. Helium is used as the compressed gas. As cryogenic liquid using liquid nitrogen or liquid methane.

In Fig.1 shows a diagram of the injector, Fig.2 shows a flange with a membrane and a nut in the context, where: 1 - fitting; 2 - adapter pipe; 3 - holes for entering cryogenic liquid; 4 - pipeline; 5 - cryo-reservoir; 6 - discharge pipeline; 7 - coupling; 8 - flange; 9 - membrane, 10 - washer; 11 - a nut.

The injector consists of a cryogenic liquid or compressed gas injection unit, a cryo-reservoir 5 and a cryogenic liquid output unit into the water tank to create conditions for intensifying the hydrate formation process therein.

The input unit includes a male fitting 1 with an external thread, having an axis along the channel connected by a capillary to a cylinder of compressed gas (not shown in Fig. 1), a transition pipe 2 with holes 3 for introducing a cryogenic liquid, and a pipe 4. The design of the injector input unit allows quick filling cryogenic reservoir of the injector with cryogenic liquid and switch to the supply of compressed gas. On the inner surface of the transition pipe 2 has a thread for screwing the fitting 1, and in the lower part of the pipe there are two through axisymmetric holes 3 for supplying cryogenic liquid into the cryogenic tank. The holes are located on the same axis opposite each other so that their axis intersects the axis of the pipe at an angle of 90 degrees. The fitting 1 when twisting into the nozzle can have two positions: holes 3 are open into the inner space of the nozzle - cryogenic fluid supply mode; openings 3 are closed - compressed gas supply under pressure from 10 to 100 atmospheres. The geometrical parameters (length and diameter) and the material of the pipeline 4 are selected from the condition of minimizing heat loss during refueling of the injector and the condition of strength when the pressure changes to 600 atmospheres.

The cryo-reservoir 5 has the shape of a cylinder with conical bottoms. The shape and geometrical parameters of the cryo-reservoir are selected from the condition of minimizing heat losses and the strength conditions when the pressure inside the cryo-reservoir changes to 600 atmospheres.

The output unit includes a waste pipe 6 with a sleeve 7 and a flange 8 with a membrane 9, a washer 10 and a nut 11. The geometric parameters (length and diameter) and material of the waste pipe 6 are also selected from the condition of minimizing heat loss when filling the injector and strength conditions when the pressure changes to 600 atmospheres The coupling 7 of the discharge pipe 6 is used to optimize its length.

The main part of the output node is a flange 8 with a membrane 9 and a washer 10, which is shown in section in FIG. 2. The membrane, made in the form of a disk of thin foil, is pressed with a washer 10 and a nut 11 to the bottom of the flange.

By changing the diameter of the hole of the washer 10, the burst pressure and, consequently, the cryogenic liquid flow rate into the water tank are controlled.

All parts of the injector are insulated to minimize heat loss (not shown in the figures).

The injector operates as follows.

First, the injector is charged with cryogenic liquid. To fill the injector with cryogenic liquid, the nozzle 1 is set to position b) (the holes 3 and the hole along the injector axis are open, the cryogenic liquid enters the cryogenic tank) so that the holes 3 are open into the interior of the transition pipe 2. The injector is lowered vertically downwards into the vessel by the injection unit with cryogenic liquid. Through holes 3 and pipe 4, the cryogenic liquid fills the cryogenic tank 5. With this method of filling the cryogenic tank, the cryogenic liquid is in equilibrium. After refueling, the injector is taken out of the reservoir with cryogenic liquid, the nozzle 1 is set to position a) - the hole along the axis of the injector is closed and the cryogenic liquid does not enter the cryogenic reservoir - by tightening the nozzle 1 all the way. Then put the membrane 9 in the flange 8, press it with the washer 10 with the hole and fix it with the nut 11. Then the injector is lowered by the flange 8 into the vessel with water. Open the valve of the cylinder with compressed gas. Helium is used as the gas. Gas is supplied under pressure from 10 to 100 atmospheres. At a pressure in the injector of 10-20 atmospheres, the membrane is destroyed and the cryogenic liquid is released into the water. The destruction of the membrane leads to the opening of the discharge pipe and the ejection (injection) of the jet of cryogenic liquid into the water and to the rapid overheating of the cryogenic liquid. The entire volume of superheated liquid explosively turns into steam. As a result of this explosive boiling of cryogenic liquid, a shock wave develops in water, the pressure in which reaches 50 atmospheres.

Justification of industrial applicability.

Experimental studies have been conducted. The working section was a vertically located thick-walled steel pipe and an injector mounted on the upper part of the pipe. The work area was filled with distilled water. The profiles of pressure waves in water were measured by two T500-2 piezoelectric pressure sensors installed in the pipe. The signals from the sensors were fed to an analog-to-digital converter (ADC E20-10) and then processed on a computer. The studies were carried out in the presence of a free surface near the place of injection of a stream of cryogenic liquid into distilled water. The measurement error was less than 1%.

At the entrance of the cryogenic liquid into water, explosive boiling occurred, accompanied by a pressure jump. The results obtained confirmed the possibility of creating the conditions necessary for the intensification of the hydrate formation process by the injector.

Claims (6)

1. The cryogenic fluid injector, including the cryogenic fluid injection unit, the cryo-reservoir and the cryogenic fluid output unit, characterized in that the input unit includes a male threaded fitting having an axis along the channel connected by a capillary to a compressed gas cylinder that is supplied under pressure from 10 to 100 atmospheres, transition pipe with thread on the inner surface for screwing in the fitting and with through axisymmetric holes for supplying cryogenic liquid, located opposite each other on the same axis crossing the pipe axis and an angle of 90 degrees, the nozzle may have two positions: a) closed hole and the cryogenic liquid does not flow into kriorezervuar; b) the openings are open and the cryogenic liquid enters the cryo-tank, and the pipeline connecting the input unit to the cryo-tank, which has the shape of a cylinder with cone-shaped bottoms, the output unit includes a waste pipe with a sleeve for optimizing the length of the pipe and a flange with a membrane in the form of a thin foil disk, which is pressed to the outlet of the cryo-reservoir, a washer, the inner diameter of which is selected depending on the pressure required to rupture the membrane, and a clamping nut. 2. The injector according to claim 1, characterized in that the geometric parameters of the pipeline, the discharge pipe and the cryo-tank are selected from the conditions of minimum heat loss and the strength condition when the pressure inside the pipelines and cryo-tank changes up to 600 atmospheres. 3. The injector according to claim 1, characterized in that all parts of the injector are thermally insulated. 4. The injector according to claim 1, characterized in that helium is used as the compressed gas. 5. The injector according to claim 1, characterized in that liquid nitrogen is used as the cryogenic liquid. 6. The injector according to claim 1, characterized in that liquid methane is used as a cryogenic liquid.

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