CN201297492Y - A recovery device of boil-off gas from a carbon dioxide storage tank - Google Patents

Abstract

The utility model relates to a recovery device of boil-off gas from a carbon dioxide storage tank, comprising a storage tank and a carbon dioxide compression system. A boil-off gas discharge tube is arranged on the storage tank and the discharge flow is controlled by a boil-off gas valve. The utility model is characterized in that the boil-off gas discharge tube is communicated with a connection pipe and is communicated with a feed gas pipe; a pressure reducing valve is arranged at the boil-off gas discharge tube in front of the connection pipe; the feed gas and the boil-off gas enter the carbon dioxide compression system through a filter valve group after being mixed. The utility model fully recycles the carbon dioxide boil-off gas with higher purity. After mixed with the carbon dioxide, the purity of the feed gas is increased, which is more favorable for gas liquefaction and greatly improves the production efficiency.

Description

Carbon dioxide storage tank evaporation gas recovery device

technical field

The utility model relates to an industrial-grade liquid carbon dioxide gas recovery device, in particular to a gas recovery device for industrial-grade liquid carbon dioxide gas evaporated in a storage tank.

technical background

In the process of production, storage and transportation of carbon dioxide, due to its own physical characteristics, it cannot be stored and transported at ultra-low temperature and low pressure such as oxygen, nitrogen, and argon, and the storage and transportation in full gaseous state is extremely cost-effective. And use medium pressure (2.0 ~ 2.5MPa) low temperature (-20 ℃ ~ -35 ℃) storage and transportation. During the storage and transportation process, the liquid carbon dioxide evaporates. In order to ensure that the pressure of the container can neither exceed the pressure nor keep the temperature low, the evaporated gas can only be discharged.

The usual practice in the above situation is:

1. Use part of the cold energy and discharge it into the atmosphere, which is a big waste.

2. Adding a small refrigeration system in the tank area can effectively solve the problem, but the process is complicated and requires a lot of investment.

Contents of the invention

In order to overcome the above disadvantages, the utility model utilizes the original production device to provide a device with simple and compact structure for recycling and utilizing the evaporated gas of the carbon dioxide storage tank.

The technical scheme of the utility model is: a carbon dioxide storage tank gas recovery device, including a storage tank, after the liquid carbon dioxide in the storage tank evaporates, it becomes gaseous carbon dioxide, which is controlled by the evaporated gas valve on the storage tank and discharged from the evaporated gas pipeline. The pressure is 1.8-2.0MPa, and the pressure is reduced to 0.05-0.1MPa through the pressure reducing valve. A connecting pipeline is added between the evaporating gas discharge pipeline and the raw material pipeline. After the evaporating gas and raw material gas are mixed, the temperature of the raw material gas drops. More water is precipitated, filtered into the filter valve group, compressed by the carbon dioxide compression system, and then filled as a product.

The pressure reducing valve mentioned therein can reduce the pressure of the evaporated gas of the carbon dioxide storage tank so that its pressure is lowered from a relatively high pressure in the storage tank to slightly higher than the pressure of the carbon dioxide raw material gas, and the evaporated gas is directly introduced into the raw material pipe to be mixed with the raw material gas.

The equipment of the utility model is simple to refit, requires less investment, fully recycles and utilizes the evaporated gas, and the purity of the evaporated gas of carbon dioxide is high. After mixing with raw material carbon dioxide, the purity of the raw material gas is improved, which is more conducive to gas liquefaction, reduces the water content of the raw material gas, and greatly improves Productivity.

Description of drawings

Fig. 1 is the structural diagram of the utility model device;

Among them: 1. Storage tank, 2. Evaporated gas valve, 3. Evaporated gas discharge pipe, 4. Pressure reducing valve, 5. Empty valve, 6. Flow control valve, 7. Connecting pipeline, 8. Raw material gas pipeline , 9, filter valve group, 10, carbon dioxide compression system.

specific facility method

As shown in Figure 1, a carbon dioxide storage tank gas recovery device, including a storage tank 1, the storage tank 1 is provided with an evaporated gas discharge pipe 3, the discharge flow is controlled by the evaporated gas valve 2, and the evaporated gas discharge pipe 3 is connected to the connecting pipe Road 7 communicates with the raw gas pipeline 8, and the evaporating gas discharge pipe 3 is provided with a pressure reducing valve 4 before connecting the pipeline to reduce the pressure of the evaporating gas from 1.8~2.0MPa to 0.05~0.1Mpa, so that Equivalent to the pressure of the raw material gas, an exhaust valve 5 is provided at the upper end of the evaporated gas discharge pipe 3 to empty the excess steam, and a flow control valve 6 is provided on the communication pipeline 7 to control the carbon dioxide evaporation gas passing through the communication pipeline. After the carbon dioxide evaporated gas is mixed with the raw material gas, the moisture and impurities in it are filtered through the filter valve group 9, and then enter the carbon dioxide compression system 10 for compression, and then it is filled as a product.

Claims (2)

1. A gas recovery device for a carbon dioxide storage tank, including a storage tank and a carbon dioxide compression system. The storage tank is provided with an evaporative gas discharge pipe, and the discharge flow is controlled by a evaporative gas valve. The raw material gas pipeline is connected, and the evaporative gas discharge pipe is provided with a pressure reducing valve before the connecting pipeline, and the raw material gas and evaporative gas are mixed and then enter the carbon dioxide compression system after passing through the filter valve group. 2. The carbon dioxide storage tank gas recovery device according to claim 1, characterized in that a flow control valve is also provided on the communication pipeline.

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