A method for comprehensive recovery and utilization of tail gas from coal chemical industry shift condensate stripping

Abstract

The invention relates to a comprehensive recycling method for coal chemical industry transformation condensate steam stripping tail gas. Under high pressure and at low temperature, ammonia and water in the steam stripping tail gas are fully desorbed by a method of cooling two poles and carrying out multi-level washing with low-temperature desalted water, so that the steam stripping tail gas reaches the standard and can enter a sulfur recycling system and a flare system of an enterprise, and the problem of environmental protection of steam stripping tail gas emission is solved fundamentally. The device has remarkable economic benefit and social benefit, investment can be recouped after two years or so, and environmental protection comprehensively reaches up to the standard. The device can be used for comprehensive treatment and utilization of similar exhaust gas.

Description

technical field [0001] The invention belongs to the waste water and waste gas treatment link in the fields of coal chemical industry, new energy chemical industry, petrochemical industry, etc., and specifically relates to the stripping gas stripped from the stripping tower in the coal chemical industry conversion condensate stripping and purification process. After gas-liquid separation, the deep purification and comprehensive utilization method of stripping tail gas containing carbon dioxide, ammonia, and hydrogen sulfide (abbreviated as stripping tail gas) discharged to the atmosphere. Background technique [0002] Coal chemical, methanol, ether, dimethyl ether and other emerging energy and chemical enterprises in the process of coal gasification and gasification gas cooling and washing, due to the temperature drop and high pressure, there will be a large amount of ammonia, carbon dioxide and a small amount of hydrogen sulfide, Carbon monoxide, hydrogen, etc. are condensed...

AI Technical Summary

Problems solved by technology

The converted condensate belongs to high-ammonia-nitrogen wastewater and cannot be directly discharged outside. If it is introduced into the wastewater biochemical treatment system of the enterprise, the ammonia nitrogen load of the biochemical system will be directly increased, and the wastewater cannot be discharged up to the standard. Most enterprises have adopted the method of stripping and distilling ammonia to remove In addition to ammonia nitrogen and carbon dioxide, the qualified liquid after gas stripping is reused in the gasification system of the enterprise

Since the temperature of the mixed gas from gas extraction is condensed at 60-80°C, the content of ammonia gas and water content are relatively high, so that the sulfur recovery system and the flare are often turned off in the later stage, which cannot operate normally, and new nitrogen oxide pollution is easy to form; in addition When the mixed gas extracted from the gas is condensed at the top of the tower, ammonium carbamate and hydrogen sulfide are enriched in a large amount at the bottom of the condenser, and the concentration is greatly increased, which makes the condenser severely corroded and cannot be used within three months. For this reason, most enterprises This part of the gas (stripping tail gas) is directly discharged, forming more serious air pollution

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