CN101181995A - Medium pressure adsorption deeply-liquefied liquid carbon dioxide reclaiming process - Google Patents

Abstract

The invention relates to a technical method used for recycling liquid carbon dioxide which is deeply liquefied by middle pressure absorption. In the method, a liquefier and a complete condenser in parallel are simultaneously liquefied during the technique procedure of liquefaction and recycling of absorbed and rectified carbon dioxide, which respectively produces industrial products and food products. The concrete operation is that a source line of the liquefier is merged into a source line of a condenser on the top of a tower after diffluence and then an exit of the condenser at the top of the tower and an exit of the liquefier are connected in parallel and enter a flash drum. The technical method has simple technique, convenient operation, high automation degree and little waste discharge. The technical method can realize deep liquefication, improve the yield coefficient and quality of liquid carbon dioxide product, increase economic benefits and be beneficial to environmental protection.

Description

The middle adsorption deeply-liquefied liquid carbon dioxide reclaiming process of pressing

Technical field:

The present invention relates to a kind of carbon dioxide recovery Technology that is used for industry and food-processing, belong to resource reutilization and green technology class.

Background technology:

Speed development along with economic construction and process of industrialization, CO2 emissions increases severely, pollution to atmospheric environment is on the rise, to the carbonic acid gas of industrial production discharging reclaim effectively, utilization and renewable resources become the particularly problem extremely paid close attention to of developed country of various countries, the world today.Meanwhile, industry, food-processing is growing to the demand of carbonic acid gas, and particularly various beverage industries such as beer, carbonated drink is flourish, and the supplydemand relationship day of foodstuff additive grade carbon-dioxide is becoming tight; Simultaneously carbonic acid gas is again a kind of very valuable resource, can be widely used in a plurality of fields such as chemosynthesis industry, mechanical protection welding, metal casting processing, agricultural fertilizer, fruit and vegetable using are fresh-keeping, beer beverage can, oil production, medical and health, fire-fighting fire extinguishing.Thereby, recycle carbonic acid gas and both can remedy the carbon source crisis that causes because of oil, Sweet natural gas mass consumption, can effectively solve Greenhouse effect again, make tellurian CO2 reach benign cycle, help environment protection.At present, the common carbon dioxide recovery Technology circuit that adopts is that unstripped gas is deeply-liquefied through carrying out after dewatering, compress, adsorbing, and produces technical grade and the food level liquid carbon dioxide product that satisfies national standard then respectively.Because the technology that adopts is comparatively backward, liquefier and complete condenser tandem working in technical process, thereby liquefaction temperature is higher, yield is unfavorable for the transportation and the storage of carbonic acid gas the end of than.

Summary of the invention:

The object of the present invention is to provide a kind of adsorption deeply-liquefied carbon dioxide reclaiming process of middle pressure that can realize that carbonic acid gas is deeply-liquefied, improve carbonic acid gas yield and product production.

Technical scheme of the present invention is as follows:

This kind liquid carbon dioxide reclaiming process is at absorption-rectification method co 2 liquefaction, reclaims in the technical process and to liquefy simultaneously liquefier is in parallel with complete condenser, difference manufacture level and food grade products, specific practice is will the liquefier source line incorporate the overhead condenser source line into after the shunting, then overhead condenser outlet and liquefier is exported to enter flash tank after in parallel.Can reduce the device liquefaction temperature like this, not influence the production food grade products again simultaneously, also can switch flexible operation at any time.When adopting this processing method, emphasis should be controlled liquid level, air input and the temperature out of overhead condenser well, and concrete technical process is as follows:

Technical grade product:

Hydrogen manufacturing workshop decarbonated exhaust gas enters compressor boost to 2.4MPa through undue water voltage stabilizing, and cooling enters the drying bed drying after dividing water, and dried material liquefies after the pre-cooler precooling, flash distillation enters storage tank, uses as the technical grade liquid carbon dioxide product.Technical grade Liquid carbon dioxide less demanding removed content and to be got final product than higher several impurity.Wherein removing of moisture adopts the method for pressurization condensation separation and molecular sieve degree of depth adsorption dewatering to slough, and light constituent flash distillations after liquefier liquefaction such as the higher methane of other content, carbon monoxide, hydrogen, oxygen, nitrogen can be removed major part;

Food grade products: hydrogen manufacturing workshop decarbonated exhaust gas is through undue water voltage stabilizing, enter compressor boost to 2.4MPa, cooling enters the drying bed drying after dividing water, dried material cooling is after adsorption bed adsorbing and removing impurity, liquefaction, rectifying after the pre-cooler precooling, enter storage tank, use as food level liquid carbon dioxide product.The food-grade carbon-dioxide request of national standard is than higher, the boiling point of impurity such as non-methane, methyl alcohol, ethanol, acetaldehyde, macromole grease is higher than carbonic acid gas in the unstripped gas, can't remove by the method for rectifying, can only remove by the method for absorption, removing of moisture adopted and the same method of technical grade product flow process, and the removing of solid residue adopted and added accurate line strainer and filter.Its middle filtrator needs routine cleaning.

Divide two-way to enter liquefier and complete condenser simultaneously carbon dioxide, reduce liquefaction temperature, then can distinguish manufacture level and food grade products.

Liquid carbon dioxide reclaiming process technology provided by the invention is simple, easy to operate, the level of automation height; waste discharge is few, utilizes this processing method can be deeply-liquefied, improves liquid carbon dioxide product yield and output; increase economic benefit, help environment protection.

Description of drawings:

Fig. 1 is a technical process route map of the present invention.Fig. 2 is technical process of the present invention, equipment configuration connection diagram.

Embodiment:

As shown in the figure, unstripped gas enters and carries out branch water in first water trap, enters and is pressurized to 2.4MPa in the compressor; Then enter the drying bed drying and deviate from moisture, enter liquefier and complete condenser through pre-cooler and carry out deeply-liquefiedly, liquefaction temperature is-24 ℃, what of material gas quantity can carry out blocked operation to liquefier and complete condenser according to; Enter flash tank during manufacture level product, then enter rectifying tower when producing food grade products.

Claims (1)

1. press adsorption deeply-liquefied liquid carbon dioxide reclaiming process in one kind, it is characterized in that: this method is at absorption-rectifying co 2 liquefaction, reclaims in the technical process and to liquefy simultaneously liquefier is in parallel with complete condenser, difference manufacture level and food grade products, specific practice is will the liquefier source line incorporate the overhead condenser source line into after the shunting, then overhead condenser outlet and liquefier is exported to enter flash tank after in parallel; Its concrete technical process is as follows:

Technical grade product: hydrogen manufacturing workshop decarbonated exhaust gas is through undue water voltage stabilizing, enter compressor boost to 2.4MPa, cooling enters the drying bed drying after dividing water, and dried material liquefies after the pre-cooler precooling, flash distillation enters storage tank, uses as the technical grade liquid carbon dioxide product; Technical grade Liquid carbon dioxide less demanding, content removed than higher several impurity get final product, wherein removing of moisture adopts the method for pressurization condensation separation and molecular sieve degree of depth adsorption dewatering to slough, and light constituent flash distillations after liquefier liquefaction such as the higher methane of other content, carbon monoxide, hydrogen, oxygen, nitrogen can be removed major part;

Food grade products: hydrogen manufacturing workshop decarbonated exhaust gas is through undue water voltage stabilizing, enter compressor boost to 2.4MPa, cooling enters the drying bed drying after dividing water, dried material cooling is after adsorption bed adsorbing and removing impurity, liquefaction, rectifying after the pre-cooler precooling, enter storage tank, use as food level liquid carbon dioxide product; The food-grade carbon-dioxide request of national standard is than higher, the boiling point of impurity such as non-methane, methyl alcohol, ethanol, acetaldehyde, macromole grease is higher than carbonic acid gas in the unstripped gas, can't remove by the method for rectifying, can only remove by the method for absorption, removing of moisture adopted and the same method of technical grade product flow process, the removing of solid residue adopted and to be added accurate line strainer and filter, and its middle filtrator needs routine cleaning;

Divide two-way to enter liquefier and complete condenser simultaneously carbon dioxide, reduce liquefaction temperature, then can distinguish manufacture level and food grade products.

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