Researching On Residual Heat Recovery Process And Technology Of Coke Plant In Chongqing Iron & Steel Co. Ltd

During coking and gas purifying, there is large amount of residual heat resource with high recovery and utilization value. Herein, the utilization of residual heat resource and energy conversation is a promising project with high potential in coke-oven plant.The coke-oven plant of Chongqing Iron& Steel Group is operating extensively with low energy resource utilization rate and inefficient residual heat resource recovery& utilization. It's a typicality production pattern among Chinese coke-oven plants. According to the production pattern of this coke-oven plant, study the coke residual heat resource and its'recovery & utilization processing and technology; present the economic compositive residual heat resource utilization technology suitable to the plant's production capacity and technical characteristic on the basis of the planning of the removal coke projection. It has practical meaning to the technology for the new coke oven plant's energy resource conversation.Through analysis of the thermal equilibrium to the coke oven, it's determined that the sensible heat recoveries of the hot coke physical thermal energy, crude gas, and combustion waste gas are the main three aspect of the residual heat recovery in coke production. Among these, hot coke physical thermal energy is prime recovery resource with an approximate occupation of 35% of the total coke oven heat. On studying to the production processing of coke oven gas purification system, residual heat resource composite, energy system structure, and the state of the art of the recovery of the heat source, it's determined that the way of residual heat resource utilization is mainly to modify the chemical processing and the high temperature recovery processing medium, the energy system mainly adopts home-grown energy resource (coke oven gas. etc.) in stead of direct outsourcing.Considering of present development tendency of the residual heat recovery technology in the coke industry, discuss the application conditions of the residual heat recovery and utilization in coke plant. Several kinds of residual heat recovery processing and technology are examined for application schemes, their probabilities and their technical economy rationality. On coal coke system, Coke Dry Quenching (CDQ) technology is primary studied on its important economic benefits and social environment consequences in stead of Coke Wet Quenching (CWQ) technology. On gas purifying system, researches are emphasized on the combinative processing of vacuum desulphurization of kalium carbonate and horizontal pipe primary cooler to recover and utilize the residual heat at the upside segment of horizontal pipe primary cooler; the energy conversation ammonia stripping processing with steam injection flash drying technology; Orientating injection column tray distilling processing. On the energy system, researches are mainly focused on the technology to use coke oven gas replaces steam: processing to use heating technology of diathermic oil replaces direct steam to ammonia stripping; technology to use direct fired absorption refrigerator replaces steam absorption refrigerator. technology on water-source heating pump of industrial circulation water; processing of circulation water with surface evaporating air cooler.The selected technology scheme of residual heat recovery processing was designed for removed coke project with the output of 2,400,000 tons of coke each year. To this project, the recovery & utilization residual heat is equivalent to 202,160 tons of coal each year. At the same time, the processing and technology for residual heat utilization are of prominent benefits to decreasing the amount of dust discharge, controlling the gas and water pollution.