Device for cryogenic freezing of soil

FIELD: disposal of solid waste.

SUBSTANCE: device comprises vehicle provided with the tank filled with coolant, collector that is used for supplying coolant and is connected with the tank though a T-shaped hose having detachable branch pipes connected with the appropriate cooling chambers. The cooling chamber is made of a box whose open section faces the surface to be frozen and receives the collector for spraying the coolant. The outer walls of the chamber are provided with face and side flanges that form a closed space for circulating coolant. The chamber walls are provided with means for interconnecting the chambers.

EFFECT: enhanced efficiency and reduced coolant consumption.

2 cl, 5 dwg

 

The invention is intended for freezing liquid and/or gaseous nitrogen to the soil surface, contaminated or waiting pollution by oil, petroleum products, flammable, explosive, toxic or chemically aggressive substances, with the aim of cleaning it.

The known method of localization and liquidation of consequences of accidental spills of hazardous liquids, which consists in the treatment of contaminated surface inert cryogenic fluid, in particular liquid nitrogen, at the same time as installation, providing this way, discusses some of the spray device is connected via pipeline to the train tank containing refrigerant [RU, patent 2169230, 2001].

The disadvantages of the method include the fact that the sputtering of nitrogen is carried out outdoors, resulting in a substantial part of the refrigeration capacity of the refrigerant as it evaporates, is lost to the environment. Furthermore, the method considers a dirt fire, explosive, poisonous and chemically active substances and is aimed at suppressing their impact on the environment. However, if we are talking about oil, high cost, there is a need for their localization and further processing - what this method does not provide.

The known method of collection n the PTI and petroleum products and device for its implementation providing accommodation on a contaminated surface of a special canopy, forming a closed space, which serves a heat carrier for heating oil pollution, and then using a vacuum unit with pumps and suction device pollution pumped out and sent for recycling [RU, patent 2111311, 1999].

The disadvantages of this method include the complexity of the structure of the device, requiring the use of a coolant, advanced pumping systems, accessories, vacuum unit, etc. in Addition, heating of the contaminated surface can cause an increase in the depth of the soil absorption oil, which is undesirable if we are talking about the pollution of the beach areas.

The known method and device for freezing and removal of contaminated soil, which consists in placing on a contaminated surface of the one or more adjacent spaced freezer boxes, through which the refrigerant circulates (CO2N2), when this move is used, a special crane [US, no 4966493, 09 At 1/00, 1990].

The disadvantages of such devices should include the fact that if you need to handle a larger area of contamination must be moved freezer boxes, and with them the faucet, in addition, the placement of the boxes neposredno the but on the ground can lead to rapid wear of the working surface of the enclosure, and the use of internal partitions in the box, staggered, hampers the circulation of the refrigerant.

Closest to the proposed and selected as a prototype is a mobile cryogenic purifier beaches, using the method of spraying liquid nitrogen, followed by removal of the frozen layer of contaminated soil and disposing of it [US, no 4043140, F 25 C 1/00, 1997].

The disadvantages of this device should include the fact that it is intended to remove the dirt with a relatively smooth surface beaches, but adjacent to the beach area may have a rocky surface. In this case, the use of this device is inconvenient. In addition, the spray device has limited overall dimensions, which does not allow to simultaneously freeze a large area of contaminated land.

This mobile device has a built-in reservoir for storage of the refrigerant of small capacity, and the freezing wet beach soil, covered with, for example, petroleum products, requires considerable refrigerant flow (nitrogen). The spraying of the coolant is carried out in the open air, with the resulting gaseous nitrogen evaporates, carrying a significant portion of the refrigeration capacity is also leads to an increase in the of ashada refrigerant.

In the design of the spray device, having a cross-section of a rectangular shape, it has two swivel section with each side of the vehicle, resulting in increased local resistance and the drop in pressure when the refrigerant flow. To maintain the required pressure in the system coolant supply is provided by the use of the pump with the motor, which leads to the complexity of the design and increase the power consumption of the device. It should also be noted that the use of cryogenic temperatures (-100÷-196° (C) requires the insulation of all elements of the system for supplying refrigerant from the reservoir to the spray nozzle in order to reduce its consumption, with high demands for materials data structures.

The proposed invention is directed to the solution of the technical problem consisting in providing cryogenic freezing of soil contaminated with petroleum products, flammable, vzryvoopasnym, toxic or chemically aggressive substances with the purpose of cleaning it.

The use of this device allows to provide the most rapid freezing of contaminated soil layer any area to clean it with regard to future removal and disposal of the frozen layer, and the required minimum consumption of expensive refrigerant./p>

The technical result consists in the elimination of these shortcomings in the device of cryogenic freezing of soil containing the vehicle with the posted capacity of the refrigerant and the manifold for the supply of the refrigerant is achieved due to the fact that the reservoir for the supply of refrigerant is connected to the tank through a flexible pipe and is made T-shaped split branches, each of which is connected with the respective cooling chamber made in the form of insulated boxes, facing the open part to the frozen surface and containing a pair of wheels, each of the cameras is mounted in the cavity of the reservoir for spraying the refrigerant, comprising a set of horizontal tubes with holes along their length for installation of the nozzles, and the outer wall of each chamber are end and side forming a closed volume for circulation of refrigerant gases, the exhaust through holes metallizovannogo fence each camera, made in its lower part, to provide pre-cooling the frozen surface around the chamber with its outer side, while the walls of the chamber have a fixation means, consisting of the locks with locking pins and clamps to connect the cameras to each other or to commit the edges in p is an operational position, as well as an additional side for docking cameras between a rigidly mounted to the outer sides of the chamber in its lower portion to provide sealing of the space between the cameras.

In addition, spray nozzles at the number - 12 pieces to cover the refrigerant 1 m2contaminated surface placed on the reservoir for spraying the refrigerant at an angle of between 10° to 30° to the vertical axis in the direction of movement of the camera, and the spray angle 60°and the distance from the nozzles to a contaminated surface is not more than 300 mm T-shaped manifold and Flex are made of insulated to ensure operating temperatures in the range from -100 to -196°C.

1 schematically shows a device for cryogenic freezing of the soil; figure 2 is a longitudinal section of the cooling chamber (type a) and transverse (type B) indicating the place of joining of two adjacent cells; figure 3 shows the side of the camera cooling: longitudinal view of the side and end flanges (type a), and the element fixing in ISO (type B); figure 4 shows the locking device in ISO: housing (type a), clamp (type B); figure 5 shows a construction of the reservoir for spraying the coolant from the spray nozzles in the ISO.

The proposed device consists of a vehicle 1 with rasmusen is th at it holding 2 with the refrigerant, connected through Flex 3 with T-shaped manifold 4 having a detachable branch 5, each of which is connected with the respective cooling chamber 6. Cooling chamber 6 is made in the form of insulated boxes, facing the open part to the frozen surface 7, is covered with dirt 8. Each chamber is equipped with 6 wheel pairs 9 and installed in the cavity of the collector 10 for spraying refrigerant, consisting of a set of horizontal tubes 11 with holes along their length to install the spray nozzle 12. The outer wall of each chamber 6 are side 13 and the end 14 of the Board with fixation elements 15 and forming a closed volume for circulation of refrigerant gases, the exhaust through holes 16 metallizovannogo fence 17, made around the perimeter of each chamber 6, in the bottom, perpendicular to the frozen surface, for pre-cooling the frozen surface 7. The outer wall of each chamber is also provided with its own fixing means 18 consisting of the locks 19 with locking pins 20 and retainers 21 for connection of the cameras 6 to each other or to commit the flanges 13, 14 in the working position. In addition, each chamber 6 has an additional side 22, is rigidly mounted to the outer sides of the camera in horizontalvelocity, for docking cameras among themselves and to ensure the sealing of the space between the cameras. Cooling chamber 6 is connected with the vehicle 1 towing cables 23.

The device operates as follows. The vehicle 1 is placed on the container of refrigerant 2 and United tow ropes 23 with one or more (depending on the width of the area of contamination) cooling chambers 6 moves covered in dirt 8 surface 7. The liquid refrigerant (nitrogen) to a temperature of -196°served through a flexible pipe 3 into the T-shaped manifold 4, with thermal insulation, and is distributed through branches 5 cooling chambers 6. Then the refrigerant enters the reservoir 10 for diffusion, where the horizontal tube 11 is evenly distributed over the holes (figures not shown), which is fixed at an angle of between 10° to 30° degrees to the vertical axis of the spray nozzle 12 with a spray angle of 60°. Using nozzles 12 liquid refrigerant irrigates and freezes contaminated surface area of 1 m2under each cooling chamber 6, formed by the evaporation of the liquid, the gaseous refrigerant to the temperature at from -100 to -180°comes With through holes 16 metallizovannogo fence 17, made around the perimeter of each of the Kama is, in a closed volume for pre-cooling the frozen surface 7 formed by removable side 13, edge 14, and more rigidly mounted butt flanges 22, placed on the outside of the cooling chambers 6. Flanges 13, 14 are fixed on the outer walls of the chamber 6 by means of fixing 18, consisting of the locks 19 with locking pins 20 and fixation elements 15 on the sides. For docking cameras 6 between a special clamps 21. The duration of freezing contaminated surface layer of a thickness of δ=5 cm, for example: oil freezing temperature t=-20°With, will make up 18 min, fuel oil with a pour point t=+4°C - 9 min, while the flow rate of the refrigerant (liquid nitrogen) depending on the temperature of the exhaust fumes will be: for oil - from 15 to 20 kg/m2space for fuel oil from 5 to 8 kg/m2square.

The frozen layer of contaminated soil subsequently cut road cut. Then use the grader containing the conveyor, loaded into a truck and transported to the place of disposal or recycling (these devices are not shown in the figure).

If the expected influx of polluted waves on some of the coastal territory, it is possible to prepare the soil by creating a protective frozen layer, necessary for the more rapid and effective containment of emergency situations, lead to pollution of the soil. To this end, the freezing of the ground surface provide with the above device, after which the frozen layer put other holedoholitiasis coverage.

Its possible that pollution has occurred on the rocky surface. In this case, you can use the Autonomous system freeze. To do this, the cooling chamber 6 remove the manifold 10 for spraying refrigerant, include in work mode, the required number of nozzles 12 and deliberately pursue freezing compliance with safety measures when working with low-temperature refrigerants.

The design of the device is simple to manufacture, requires no electricity. Refers to the placement on vehicle capacity refrigerant volume 5, 8, or 16 m3that will allow without refueling process, the surface area of from 1000 to 10000 m2. The use of exterior sides, forming a closed volume for pre-cooling the frozen surface, and insulation of piping, in which the refrigerant flow, allows for significant reduction in the consumption of expensive refrigerant, due to more complete use of its cooling capacity. In General, the device allows the t to quickly and efficiently provide localization and liquidation of consequences of accidental contamination of the soil (clean) oil, petroleum products, flammable, explosive, poisonous and chemically aggressive substances.

1. Device for cryogenic freezing of soil containing the vehicle with the posted capacity of the refrigerant and the manifold for the supply of the refrigerant, characterized in that the reservoir for the supply of refrigerant is connected to the tank through a flexible pipe and is made T-shaped split branches, each of which is connected with the respective cooling chamber made in the form of insulated boxes, facing the open part to the frozen surface and containing a pair of wheels, each of the cameras is mounted in the cavity of the reservoir for spraying the refrigerant, comprising a set of horizontal tubes with holes along their length to install the injectors, and outer walls of each chamber are end and side forming a closed volume for circulation of refrigerant gases, the exhaust through holes metallizovannogo fence each camera, made in its lower part to provide pre-cooling the frozen surface around the chamber with its outer side, while the walls of the chamber have a fixation means, consisting of the locks with locking pins and clamps to connect the cameras to each other or to FIC the purpose of the boards in the working position, as well as an additional side for docking cameras between a rigidly mounted to the outer sides of the camera, in its lower part, to ensure the sealing of the space between the cameras.

2. The device according to claim 1, characterized in that the spray nozzle 12 pieces to cover the refrigerant 1 m2contaminated surface placed on the reservoir for spraying the refrigerant at an angle of 10 to 30° to the vertical axis in the direction of movement of the camera, and the spray angle of each nozzle is 60°and the distance from the nozzles to a contaminated surface is not more than 300 mm

3. The device according to claim 1, wherein the T-shaped manifold and Flex are made of insulated, ensuring values of temperatures in the range from -100 to -196°C.



 

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