Waste heat utilization device for oxalyl chloride rectifying tower

Abstract

The utility model relates to the technical field of waste heat recovery in chemical industry production, and particularly discloses a waste heat utilization device for an oxalyl chloride rectifying tower, which comprises a steam discharge pipe communicated with the top of the rectifying tower; the gas-liquid separator is communicated with the free end of the steam discharge pipe; the purification heat storage device is communicated with the gas-liquid separator, the purification heat storage device comprises a purification heat storage barrel and a filter element adsorption layer arranged in the purification heat storage barrel, the purification heat storage barrel is divided into a purification cavity and a heat storage cavity by the filter element adsorption layer, the purification cavity is sequentially provided with a plurality of adsorption layers from the filter element adsorption layer to the outside, and the heat storage cavity is communicated with the purification cavity. A detachable heat storage block is arranged in the heat storage cavity in a surrounding mode, an exhaust pipe communicated with the purification cavity is arranged on the side wall of the side, away from the heat storage cavity, of the purification heat storage barrel, and the problems that when a traditional waste heat recovery device conducts waste heat recovery on the oxalyl chloride rectifying tower, liquid in a pipeline is not treated, water is left in the pipeline, and the waste heat recovery effect is affected are solved. And the normal circulation effect of hot air is influenced.

Description

Technical Field

[0001] The present application relates to the technical field of waste heat recovery in chemical production, and specifically discloses a waste heat utilization device for an oxalyl chloride distillation tower. Background Art

[0002] A distillation tower is a tower-type vapor-liquid contact device for distillation. There are two main types of distillation towers: plate towers and packed towers. The distillation tower utilizes the different volatilities of the components in the mixture, that is, the different vapor pressures of the components at the same temperature. The light components (low boiling substances) in the liquid phase are transferred to the gas phase, and the heavy components (high boiling substances) in the gas phase are transferred to the liquid phase, thereby achieving the purpose of separation. The distillation tower is also a mass transfer and heat transfer device that is extremely widely used in petrochemical production. In the actual chemical production of the distillation tower, a large amount of steam will be generated, and the steam contains a large amount of heat. If the steam is discharged directly, it will cause energy waste and pollute the environment.

[0003] The Chinese utility model patent with the patent number CN215841663U discloses a waste heat recovery device for an oxalyl chloride distillation tower, which includes a cooling box and a filter box. The tops of the cooling box and the filter box are both provided with a first box cover and a second box cover. The top of the first box cover is connected to the bottom end of the air duct, and the outer wall of the air duct is provided with an air valve. The waste heat recovery device for the oxalyl chloride distillation tower is provided with a pump body, a cooling box, a ring pipe, a water pipe, a connecting pipe, a heat pipe and a second observation box. The heated water can be extracted through the pump body for use in the distillation tower, and can also be discharged for free use. At the same time, a part of the steam after cooling can be discharged through the connecting pipe for use in the distillation tower, so as to adjust the temperature and air pressure in the distillation tower. Secondly, the gas can flow in the heat pipe, and the heat pipe can be buried in the ground or set up indoors for heating. The waste heat generated is fully recovered and utilized through the above, and the waste of heat energy is reduced; however, the utility model still has certain defects. For the condenser, the steam temperature in the condenser tube is It is greater than the peripheral condensed water, so the hot steam in the pipe will liquefy due to the cooling, and then liquid will appear in the pipe. However, the utility model lacks a processing procedure for this part of the liquid, resulting in water accumulation in the pipe, affecting the normal circulation effect of the hot gas. Secondly, the existing waste heat recovery device does not process the trace oxalyl chloride contained in the exhaust gas, and oxalyl chloride itself is a toxic gas. If the pipeline is accidentally damaged, the oxalyl chloride gas will leak. People near the pipeline will be at risk of inhaling oxalyl chloride, which will cause serious damage to the body. Therefore, in view of this, the inventor provides a waste heat utilization device for an oxalyl chloride distillation tower to solve the above problems. Utility Model Content

[0004] The utility model aims to solve the problem that when a traditional waste heat recovery device recovers waste heat from an oxalyl chloride distillation tower, the liquid in the pipeline is not processed, resulting in water accumulation in the pipeline and affecting the normal circulation effect of hot gas.

[0005] In order to achieve the above-mentioned object, the basic scheme of the utility model provides a waste heat utilization device for an oxalyl chloride distillation tower, comprising:

[0006] a steam discharge pipe connected to the top of the distillation tower;

[0007] a gas-liquid separator, connected to the free end of the steam exhaust pipe;

[0008] A purification heat storage device is connected to the gas-liquid separator, the purification heat storage device comprises a purification heat storage cylinder and a filter element adsorption layer arranged in the purification heat storage cylinder, the filter element adsorption layer divides the purification heat storage cylinder into a purification chamber and a heat storage chamber, the purification chamber is provided with a plurality of adsorption layers in sequence from the filter element adsorption layer to the outside, a detachable heat storage block is arranged around the heat storage chamber, and a side wall of the purification heat storage cylinder away from the heat storage chamber is provided with an exhaust pipe connected to the purification chamber

[0009] Furthermore, it also includes a heat exchanger which is arranged between the top of the distillation tower and the gas-liquid separator and is used to cool the steam exhaust pipe.

[0010] Furthermore, the heat exchanger includes a heat exchange cylinder, a water inlet pipe and a water outlet pipe respectively connected to two opposite sides of the heat exchange cylinder, and the steam exhaust pipe is spirally wound in the heat exchange cylinder and passes through the heat exchange cylinder to be connected to the gas-liquid separator.

[0011] Furthermore, it also includes a water tank, which is connected to the water inlet pipe and is used to supply coolant to the heat exchanger. The water inlet pipe is provided with a water inlet pump.

[0012] Furthermore, the gas-liquid separator comprises a gas-liquid separation cylinder and a gas-liquid separation membrane arranged on the top of the gas-liquid separation cylinder, and a liquid discharge pipe is arranged on the side wall of the gas-liquid separation cylinder.

[0013] Furthermore, the connection position between the steam exhaust pipe and the gas-liquid separator is located below the gas-liquid separation membrane, and the top of the gas-liquid separation cylinder is connected to the top of the purification heat storage cylinder.

[0014] Furthermore, the adsorption layer includes a biological adsorption layer and an activated carbon adsorption layer.

[0015] Compared with the prior art, the principle and effect of the utility model are:

[0016] Compared with the prior art, the utility model absorbs heat from residual oxalyl chloride vapor in the production process by surrounding the heat storage block arranged in the purification heat storage cylinder. Compared with the traditional technology of directly passing the residual oxalyl chloride vapor into the heat pipe to utilize the waste heat for indoor heating, the use of heat storage blocks for waste heat absorption is safer and avoids the leakage of toxic gases during indoor heating. By arranging a gas-liquid separation cylinder and a drain pipe that can separate the oxalyl chloride gas and liquid, the condensed oxalyl chloride solution and oxalyl chloride vapor can be separated in time, thereby ensuring that in the next step of waste heat absorption and utilization, only uncondensed oxalyl chloride vapor is present, and a collection space is provided for the condensed oxalyl chloride solution. The collected oxalyl chloride solution can be subsequently discharged to the outside through the drain pipe for repeated use, thereby reducing the cost of raw materials. By arranging a filter element adsorption layer, a biological adsorption layer and an activated carbon adsorption layer, harmful parts in the mixed gas that absorbs the waste heat can also be absorbed and purified, thereby ensuring the safety of the gas during discharge. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A system flow chart of a waste heat utilization device for an oxalyl chloride distillation tower proposed in an embodiment of the present application is shown;

[0019] Figure 2 A schematic diagram of the internal structure of the purification heat storage cylinder proposed in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0020] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the utility model, the specific implementation method, structure, characteristics and effects of the present invention are described in detail below in combination with the accompanying drawings and preferred embodiments.

[0021] The figure marks in the drawings of the specification include: distillation tower 1, steam exhaust pipe 2, water inlet pipe 3, water storage tank 4, water outlet pipe 5, heat exchange cylinder 6, gas-liquid separation cylinder 7, gas-liquid separation membrane 8, drain pipe 9, purification heat storage device 10, exhaust pipe 11, activated carbon adsorption layer 12, biological adsorption layer 13, filter element adsorption layer 14, heat storage block 15.

[0022] A waste heat utilization device for an oxalyl chloride distillation tower, for example Figure 1As shown, it includes a steam discharge pipe 2 connected to the top of the distillation tower 1, a heat exchanger for condensing the steam discharge pipe 2, a gas-liquid separator connected to the end of the steam discharge pipe 2, and a purification heat storage device 10 connected to the gas outlet end of the gas-liquid separator, as follows:

[0023] Heat exchanger: The heat exchanger includes a heat exchange cylinder 6, a water inlet pipe 3 and a water outlet pipe 5 connected to the two opposite sides of the heat exchange cylinder 6, respectively. The steam discharge pipe 2 is spirally wound in the heat exchange cylinder 6 and passes through the heat exchange cylinder 6 to connect with the gas-liquid separator. Correspondingly, a water storage tank 4 is configured to supply water to the heat exchanger. The water inlet pipe 3 is connected to the water storage tank 4 and is provided with a water inlet pump. Before condensation, water needs to be supplied through the water inlet pump to fill the heat exchange cylinder 6 with condensed water. After condensation is completed, the water in the heat exchange cylinder 6 that has been heated due to condensation can be discharged through the drain pipe as needed.

[0024] Gas-liquid separator: The gas-liquid separator includes a gas-liquid separation cylinder 7 and a gas-liquid separation membrane 8 arranged on the top of the gas-liquid separation cylinder 7. The connection position between the steam exhaust pipe 2 and the gas-liquid separator is located below the gas-liquid separation membrane 8. The top of the gas-liquid separation cylinder 7 and the top of the purification heat storage cylinder are interconnected. The side wall of the gas-liquid separation cylinder 7 is provided with a discharge pipe 9 located below the gas-liquid separation membrane 8.

[0025] The purification heat storage device 10 comprises a purification heat storage cylinder and a filter element adsorption layer 14 arranged in the purification heat storage cylinder. The filter element adsorption layer 14 divides the purification heat storage cylinder into a purification chamber and a heat storage chamber. The purification chamber is provided with a plurality of adsorption layers in sequence from the filter element adsorption layer 14 to the outside. The adsorption layers comprise a biological adsorption layer 13 and an activated carbon adsorption layer 12. A detachable heat storage block 15 is arranged around the heat storage chamber. An exhaust pipe 11 connected to the purification chamber is arranged on a side wall of the purification heat storage cylinder away from the heat storage chamber.

[0026] The specific implementation process is as follows:

[0027] First, water is supplied through the water inlet pump to fill the heat exchange cylinder 6 with condensed water. When the oxalyl chloride steam in the distillation tower 1 is produced, it enters the steam discharge pipe 2. When the pipe body of the steam discharge pipe 2 passes through the heat exchanger, the steam in the steam discharge pipe 2 is cooled down due to the heat absorption of the condensed water in the heat exchange cylinder 6, and the condensed water in the heat exchange cylinder 6 is heated up. In addition, due to the effect of condensation, the oxalyl chloride steam in the steam discharge pipe 2 begins to liquefy continuously. Subsequently, the gas-liquid mixture in the steam discharge pipe 2 is passed into the gas-liquid separation cylinder 7. Under the action of the gas-liquid separation membrane 8 at the top of the gas-liquid separation cylinder 7, the oxalyl chloride gas and the solution are separated. To achieve separation, the solution remains in the separation cylinder, and the gas moves upward through the gas-liquid separation membrane 8 to enter the next process, that is, the separated gas is discharged into the purification heat storage cylinder, and the heat storage block 15 in the purification heat storage cylinder continuously absorbs the residual heat of the oxalyl chloride vapor. Then, the exhaust pipe 11 is opened, and the oxalyl chloride vapor that has absorbed the heat passes through the filter element adsorption layer 14, the biological adsorption layer 13 and the activated carbon adsorption layer 12 in turn, so as to purify the toxic gas and finally discharge it to the outside. The condensed water heated in the heat exchange cylinder 6 and the condensed liquid collected in the gas-liquid separation cylinder 7 in the process can be recycled according to actual needs.

[0028] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A waste heat utilization device for an oxalyl chloride distillation tower, characterized in that: include: a steam discharge pipe connected to the top of the distillation tower; a gas-liquid separator, connected to the free end of the steam exhaust pipe; A purification heat storage device is connected to the gas-liquid separator, and the purification heat storage device includes a purification heat storage cylinder and a filter element adsorption layer arranged in the purification heat storage cylinder, the filter element adsorption layer divides the purification heat storage cylinder into a purification chamber and a heat storage chamber, the purification chamber is provided with a plurality of adsorption layers in sequence from the filter element adsorption layer to the outside, a detachable heat storage block is arranged around the heat storage chamber, and an exhaust pipe connected to the purification chamber is arranged on a side wall of the purification heat storage cylinder away from the heat storage chamber.

2. The waste heat utilization device for an oxalyl chloride distillation tower according to claim 1, characterized in that: It also includes a heat exchanger which is arranged between the top of the distillation tower and the gas-liquid separator and is used to cool the steam exhaust pipe.

3. A waste heat utilization device for an oxalyl chloride distillation tower according to claim 2, characterized in that: The heat exchanger comprises a heat exchange cylinder, a water inlet pipe and a water outlet pipe respectively connected to two opposite sides of the heat exchange cylinder, and the steam exhaust pipe is spirally wound in the heat exchange cylinder and passes through the heat exchange cylinder to be connected to the gas-liquid separator.

4. The waste heat utilization device for an oxalyl chloride distillation tower according to claim 3, characterized in that: It also includes a water storage tank, which is connected to the water inlet pipe and is used to supply coolant to the heat exchanger. The water inlet pipe is provided with a water inlet pump.

5. A waste heat utilization device for an oxalyl chloride distillation tower according to any one of claims 1 to 4, characterized in that: The gas-liquid separator comprises a gas-liquid separation cylinder and a gas-liquid separation membrane arranged on the top of the gas-liquid separation cylinder, and a liquid discharge pipe is arranged on the side wall of the gas-liquid separation cylinder.

6. The waste heat utilization device for an oxalyl chloride distillation tower according to claim 5, characterized in that: The connection position between the steam exhaust pipe and the gas-liquid separator is located below the gas-liquid separation membrane, and the top of the gas-liquid separation cylinder is connected to the top of the purification heat storage cylinder.

7. The waste heat utilization device for an oxalyl chloride distillation tower according to claim 1, characterized in that: The adsorption layer comprises a biological adsorption layer and an activated carbon adsorption layer.

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