Analysis And Application Of Evaluation Index System Of Cleaner Production Level For Coking And Gas Purification Processes

In recent years, there were high energy & material consumption plus excessive pollutant emission in the development of domestic coking industry, especially in the coking and gas purification. One of the effective solutions to this problem is clean production, which aims to decrease energy & material consumption as well as pollutant emission through strengthening the overall control and comprehensive utilization of the production from the source.In 2003 China issued the Standard of Cleaner Production in Coking Industry(hereinafter referred to as the Standard). In 2014, MIIT released the Evaluation Standard of Cleaner Productions Level in Coking industry, in which the Evaluation Index System of the Cleaner Production Level of the Coke Making and Gas Purification(hereinafter referred to as the System)was established. In comparison with the Standard, the System makes great changes, including the introduction of various new indexes and the improvement of certain existing indexes in the Standard in terms of content or requirement. Currently the examiners of clean production lack experience in the application of the System and relevant research papers are not available. Therefore, it is essential to conduct an in-depth analysis of the changes in the System in order to promote the deep understanding and effective application of the System. The research results of this paper are as following:(1) Made a comparison between the System and the Standard; analyzed the newly introduced indexes of the System as well as the various indexes that need to be improved. There are 14 newly-added indexes and 7 indexes that need to be improved(not including indexes concerning pollutants production and emission control).Besides, this paper analyzed the source of these indexes and the influence of the changed indexes on enterprise's energy consumption, the production of pollutants,products and economic indexes. This paper also put forth some suggestions and measures for enterprises to better meet the requirement of indexes. Meanwhile, this paper made a detailed analysis of the treatment of the three wastes produced in the process of coke making.(2) The defects of the System are identified and the improvement put forward.For example, the recycle of waste heat in coking smoke and rising pipe gas in cokeoven should be taken into consideration when it comes to the comprehensive utilization of resources. The optimizing heating cascade control system of the coke oven should be taken into consideration when it comes to the index of the optimizing heating control system of coke oven.And it is suggested that some qualitative indexes be added for products.(3) According to the System, case studies are carried out in Hong Yuan Coal Company, the results of which indicate that the clean production level of the company meets the domestic average and is consistent with current situation of the enterprise.This indicates that the System is more feasible and scientific.According to the content of index analysis and system improvement, a series of clean production solutions are put forward for enterprises, mainly including the application of the technology of dry quenching and the coke oven optimizing heating cascade control system, the recycle of the coke flue gas waste heart and the steam condensate and the cooking water of high temperature in the primary cooler and the project of the extraction of salt from waste liquid of desulfurization, etc.This research results of this paper will serve as the guidance and technological direction for the clean production examination in coke making and gas purification industry. Meanwhile, the research also serves as reference for the research of clean production in other fields.