Purification method for yellow phosphorus exhaust gas and device thereof

Abstract

The invention discloses a yellow phosphoric tail gas purification method and a device thereof. Aiming at the characteristics of tail gas containing multi-form impurities such as phosphide, sulphide, arsenide, fluorid and the like, the pretreatment of yellow phosphoric tail gas utilization is effectively carried out. The yellow phosphoric tail gas fuel gas purification device comprises a yellow phosphoric tail gas fuel gas pretreatment device (I) and a yellow phosphoric tail gas fuel gas follow-up purifying device (II). A special dephosphorization desulphurization dearsenization unit triplet catalytic oxidation catalyst is used for absorbing H2S and PH3 and residual AsH3 in a tower. The invention comprises a turbulence little lime washing dust-removal system, a washer lime cream washing, and adesorption fluroid, part arsenide and phosphorus, oxysulphide system. The invention realizes that the yellow phosphoric tail gas with the thermal value as high as 10048-11723KJ / Nm is effectively utilized, solves the key difficult problem that yellow phosphorus manufactures can not effectively use yellow phosphoric tail gas as fuel gas. The purified yellow phosphoric tail gas can meet the fuel gas requirements of a gas fired boiler and a fuel gas electric generating set and can be circularly and comprehensively used by the yellow phosphoric manufactures, thus laying the foundation for the sustainable development of the yellow phosphorus industry.

Description

technical field [0001] The invention relates to a yellow phosphorus tail gas purification method and its device, in particular to a purification method and a system complete set of yellow phosphorus tail gas combustion purification method. Background technique [0002] At present, almost all yellow phosphorus in the world is produced by electric furnace method. China's yellow phosphorus production has a history of 60 years. At present, there are more than 130 yellow phosphorus production enterprises. The production process produces a large amount of yellow phosphorus tail gas. The by-product yellow phosphorus tail gas of 1 ton of yellow phosphorus is about 2500-3000Nm 3 , the tail gas is rich in CO (82-95%) (vol.) (while the average content of CO in water gas is below 20%), the calorific value is 10.7475-12.0119MJ / m 3 , which is a gaseous fuel with medium calorific value, can be used as a fuel, per Nm 3 The calorific value of yellow phosphorus tail gas is 10.6763~11.9324MJ...

AI Technical Summary

Problems solved by technology

Due to the small production capacity, large quantity, wide distribution, and difficulty in collecting tail gas of a single yellow phosphorus electric furnace for phosphorus production, yellow phosphorus tail gas is mainly used as fuel for medium and low pressure boilers, such as for drying raw materials and producing hot water steam, etc., but due to yellow phosphorus Phosphorus tail gas contains harmful and corrosive components such as phosphorus, sulfur, arsenic, and fluorine. Using it as a conventional gas will lead to corrosion failure of boiler components and greatly shorten the life of equipment.

For example: A chemical industry company in Yunnan completed the "Yellow Phosphorus Tail Gas Replacement Boiler Combustion Coal Energy-Saving Technological Improvement Project" at the end of 1998. However, during the process of using yellow phosphorus tail gas as fuel, it was found that the boiler corrosion was very serious when the yellow phosphorus tail gas was burned. After 3 After a month of operation, the boiler was scrapped due to corrosion breakdown; a chemical company in Sichuan, after being purified by the yellow phosphorus tail gas purification equipment that the company thought was feasible, used it as the fuel for two 40 tons / hour steam boilers. Severe corrosion and scrapped; a chemical research institute in Nanjing, a 100Kg / cm 2 Heat exchanger, the heat exchanger tube was scrapped due to corrosion in less than a month; a phosphorus products company in Yunnan invested in the construction of three hot water boilers, and the superheated surface in the boiler was corroded and broken down after running for 3 to 4 months, so the heat exchange parts were frequently replaced Wait

Therefore, the utilization of yellow phosphorus tail gas is less than 20%, and these waste gases are all burned into CO 2 , SO 2 、H 2 S.PH 3 Waiting to be discharged into the atmosphere, on the one hand, it wastes important and precious carbon monoxide resources, and at the same time, it aggravates the pollution of the atmospheric environment

[0004] Yellow phosphorus production consumes a lot of energy and costs, which has become the main factor restricting the sustainable development of phosphorus chemical industry

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