Brief Analysis On Green New Deal of Iron & Steel Industry and PM2.5 Pollution Control Countermeasures in China

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1 Applied Mechanics and Materials Submitted: ISSN: , Vols , pp Accepted: doi: / Online: Trans Tech Publications, Switzerland Brief Analysis On Green New Deal of Iron & Steel Industry and PM2.5 Pollution Control Countermeasures in China Cuiyan Jiao 1, a *, Gang Ren 1,b, Tiebing Xu 1,c and Qinghui Liu 1,d 1 Environmental Science Research Institute of Hebei Province, No.30 Yaqing Street Shijiazhuang City, China a *jcy663918@163.com, b rengang15@163.com, c xutb@foxmail.com, d liuqinghui20@sohu.com Keywords: Green new deal, Iron & Steel Industry, PM 2.5 pollution control Countermeasures. Abstract. In recent years, environmental protection has attracted unprecedented attention as the frequent occurrence of the haze phenomenon in China. The Iron & Steel industry, as the representative of the industries with heavy pollution, high energy consumption and excess production capacity, has became the focus of the attention. In this article, the effect of new laws, regulations and standards of environmental protection on the development of the Iron &Steel industry in China has been compared and analyzed. According to the new environmental protection request, combined with the current new technology and new materials, the pollutant emission has been reduced to the maximum, and the policy and technical support for the energy conservation and emission reduction as well as the sustainable development of the Irion &Steel industry has been provided. Introduction The Iron &Steel industry is one of the most important basic industries of Chinese national economy, which has got rapid development after 1990s. According to the statistics, during the 11th five-year plan period, China s crude steel production increased from 350 million tons to 630 million tons, with the annual growth rate of 12.2%. The domestic oriented consumption of the crude steel orientation is comprehensively forecasted to reach about 750 million tons by 2015[1], compared with the number ten years ago, the crude steel production growth will enter the smooth development stage. In 2010, the comprehensive energy consumption of per ton steel fell to 605 kilograms of standard coal, decreased 12.8% compared with In 2011, per ton steel smoke/dust and SO2 emissions in the key large and medium-sized Iron &Steel enterprises reduced to 1.03kg/t and 1.67kg/t, decreased 48.08% and 37.2% respectively compared with The development of the Iron &Steel industry inevitably leads to the environmental pollution, due to its high pollution emission, intensive energy consumption and significant number of plants. Recently, the environmental pollution has been attracted unprecedented attention with the occurrence of the haze phenomena. Especially the study of PM2.5 has become the research hotspot. Since on the one hand, PM2.5 can absorb a variety of harmful substances due to its huge specific surface area, on the other hand, it has long-distance transmission ability due to its long residence time in the atmosphere, which affect human health and the visibility of the ambient air[2,3]. The Iron &Steel industry is the major particulate matter emitter, therefore, it has became the key in the pollution-control industry. The Chinese government has introduced new laws and regulations, policies and standards, which will bring significant influence on the development of the Iron &Steel industry. Brief analysis on green new deal of Iron & Steel Industry in China (1) Government laws On April 24, 2014, the environmental protection law of the People s Republic of China (revised draft) was approved by the National People s Congress. The draft has pointed out that the local governments shall take effective measures to improve the environmental quality according to the environmental protection targets and tasks. For those local governments in the key areas that do not All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-11/05/16,16:35:10)

2 1002 Environmental Technology and Resource Utilization II meet the national environmental quality standards, shall draw up the planning deadlines and take measures in time [4]. At present, some local governments have rolled out a series of stricter administrative commands. For example, Tang Shan city government requires the Coke Dry Quenching (CDQ) as well as the dust removal transformation of the BOF dry flue gas be accomplished within the stipulated time. Meanwhile, the particulate matter emission of the casting house shall satisfy the requirement of special emissions limits. (2) Relevant administrative regulations and policies On October 24, 2011, the 12 th five-year development plan for the Iron &Steel industry was issued by the Ministry of Industry and Information. The requirement that the Coke Dry Quenching (CDQ) rate reaches above 95% by 2015 was put forward. Meanwhile, the planning objectives such as the energy consumption and CO2 emission of per unit production decreases 18%, respectively; the average comprehensive energy consumption of per ton steel in the key Iron &Steel enterprises be less than 580 kilograms, the new water consumption of per ton steel be lower than 4.0 cubic meters; the SO2 emission be less than 1kg per ton steel production, declined 39%; the Chemical Oxygen Demand (COD) be less than 0.065kg per ton steel production, declined 7%; the solid waste comprehensive utilization be more than 97% were proposed. In August 2012, the circular of 12 th five-year plan for energy conservation and emissions reduction was printed and distributed by the state council, which required that, by 2015, the comprehensive energy consumption of Iron &Steel industry reduces to 580kg standard coal, SO2 emissions reduces to about 1.8 million tons, cut 27%, the desulfurization efficiency of all the sintering and pelletizing equipments in the urban build-up areas reaches above 95%, the H2S removal efficiency of the coke oven gas reaches above 95%, etc. Besides the improvement of the traditional environmental protection facilities, the denitration of the sintering machine is also proposed[5]. In September 2013, the action plan for the control of air pollution was promulgated by the state council. Specific requirements are as follows: amending the industry access conditions, clearing the resource & energy conservation and pollutant emission index; Setting local industry admittance catalogue which is stricter than the national standards and in accordance with the requirements of the local function orientation; Implementing innovative clean production, using advanced and applicable technologies, processes and equipments; The pollution emission intensity of the key industries decreasing more than 30% than the year 2012 by 2017; The desulfurization facilities should be installed in all the sintering and pelletizing equipments. It is required that the new Iron &Steel enterprises of 47 key cities in the Bingjing-Tianjin-Hebei region, Yangtze river delta region and Pearl river delta should perform air pollutants emission limits. In general, the new requirements for the Iron &Steel industry such as controlling capacity, strict managements, improving industry access condition, promoting the reform has became the current environmental status. (3) Environmental protection standards In 2012, the Chinese government promulgated a series of standards such as Ambient air quality standards, Emission standard of pollutants for mining and mineral processing industry, Emission standard of air pollutants for sintering and palletizing of iron and steel industry, Emission standard of air pollutants for steel smelt industry, Emission standard of pollutants for coking chemical industry, Emission standard of air pollutants for iron smelt industry, Emission standard of air pollutants for steel rolling industry and Discharge standard of water pollutants for iron and steel industry in succession. The average PM2.5 concentration limit was added in the new Ambient air quality standards, the contribution and impact of PM2.5 to the environment in the new/rebuilding/extending iron and steel project was fully considered. Meanwhile, the standards also tightened the concentration limits of PM10, NO2, Pb, and benzo[a] pyrene, which greatly improved the threshold of the coking chemical industry. In February 2013, the Notice to the execution of special atmospheric pollutants emission limits was issued by the Ministry of Environmental Protection. The industries such as the thermal power, Iron &Steel, petrochemical, cement, nonferrous metal, chemical, etc. in the 47 cities of the Beijing-Tianjin-Hebei, Yangtze River Delta and Pear River Delta areas have to implement the air

3 Applied Mechanics and Materials Vols pollutants emission limits. The documents required that, the new accepted environmental impact assessments projects shall execute the air pollutants emission limits value by April 1 st, Meanwhile, the smoke emitted by the sintering (palletizing) equipments in the above-mentioned 47 cities shall perform the special emission limits by 1 st January, Solutions and correlative technique (1) Facilitate the emission reduction Developing the pollutant source control technology from the whole process is an important trend of the emission reduction technology. Sintering flue gas circulation technology can significantly reduce the exhaust gas emissions of the process as well as the pollutants emission without reducing the production, reduce energy consumption and recover the flue gas waste heat of sintering process as much as possible, which is the main direction of upgrading the sintering machine in China. The long-term practice proves that Shougang Jintang United Iron &Steel Co., Ltd etc saved energy consumption and reduced emission by optimizing the streamline processes. By introducing such technology as one pot, continuous casting and rolling, hot charging hot delivery to achieve good effect in the interface cohesions of iron-making, steel-making and steel-rolling processes[6]. Besides, efficient blast furnace coal injection technology, full oxygen blast furnace technology, dehumidifying blast technology on BF, blast furnace and hot blast stove double preheating technology, scrap preheating technology, electronic furnace flue gas waste heat recovery and dust removal technology, regenerative combustion technology, low temperature rolling technology, on-line heat treatment technology, etc, contribute to the energy conservation and emission reduction of the Iron &Steel industry. (2) Increase the waste heat recovery The increase of the energy consumption of the environmental protection facilities makes it difficult to lower the energy consumption of the whole industry. The Iron &Steel industry should further explore the secondary energy recycling technique due to the increasing strict limit requirements for the Iron &Steel industry in China. The promotion of the advanced technology as dry quenching, coal moisture control, sensible heat recovery of the coke oven raw gas, blast furnace top gas recovery turbine (TRT), integration of dry technique for converter flue gas treatment and cogeneration, etc, has obtained remarkable energy saving effect. The development and application of the technique such as the sensible heat recovery of the metallurgical slag, the waste heat recovery of the sintering mine etc, with large recycling potential should be the focus of the future work. (3) Strengthen the end treatment a. Control of the particulate matter and PM2.5 At present,few study and engineering examples has been reported on the fine particulate matter control of the Iron &Steel industry, which is still in the investigating stage of the particulate emission characteristics. As the particulate matter emission standards tightening up, it is generally considered that only the bag dust collector and electric bag filter can effectively guarantee long-term and stable state of achieving the requirement of the emission standards. The following aspects should be paid attention to in the treatment of fine particulate matter. First, the bag filter should break through the traditional technology, be paid more attention to the processing and manufacturing level of the dust removal apparatus, the appropriate selection of the filter materials, the efficient flexible soot, dust collector plate design as well as the cage and bag filter processing. The importance should also be attached on the technology development such as anti-blocking when discharging as well as the secondary dust control. The emission of PM2.5 could be effectively controlled by selecting the water thorn felt filter materials, new coating filter materials, tectorial filter materials and spunlace-felt filter materials plus tectorial filter materials with optical performance and good stability [7].

4 1004 Environmental Technology and Resource Utilization II Second, the electricity composite filter bag with high collecting efficiency of fine particulate matte is mainly depending on its capture mechanism and process. In order to increase the capture efficiency, measures should be taken on improving the filter efficiency of the electrostatic micro distance and the structure of the filter materials [8]. Third, the emission of the flue gas will be increased instantaneously due to the fault management and the abnormal materials supply, especially in the converter and electric furnace workshop, the dust removal ability of the system can not meet the instantaneous gas capture requirement, leading to the unorganized emission phenomenon. Studies have shown that the particle size of the particulate matter spread to the top to the electric furnace workshop is mostly less than 2.5µm[7], therefore, the roof dust removal apparatus should be set to capture PM2.5 emitted by ventilation system effectively. This new environmental protection technology first applied on the converter project of BaoSteel Group, is promoted to more than 10 converters by now. b. Multi-pollutant collaborative processing technology The multi-pollutant collaborative processing technology is the inevitable trend for the pollution control of the sintering flue gas. There are several practical applications in the domestic Iron &Steel enterprises by now such as the activated carbon adsorption technology of Taiyuan Iron &Steel group, LJS-FGD technology of BaoSteel Group and MEROS technology of MaSteel Group. Suggestions on pollution control proposal of the iron&steel industry (1) The systematic and in-depth basic research on the emission characteristics of PM2.5 and the pollutants such as benzene [a] pyrene, dioxins and heavy metals should be taken to provide technical support for the technology development and application of the pollutant treatment. (2) Accelerating the introduction, digestion and R&D application of the various-pollutants collaborative processing technology. (3) Formulating relevant policies to support the development, upgrading and expansion of the related Iron &Steel environmental protection industry. In particular in the bag filter industry, in order to lower the economic pressure of the upgrading of the environmental protection facilities, the Iron &Steel enterprises should narrow the gap in and abroad on the aspects of material, sewing technique, dust removal, process control and daily managements. References [1] Ministry of Industry and Information Technology of the People s Republic of China, the 12 th five-year plan of Iron &Steel Industry. [EB/OL]. In Chinese n /n /n /n / html. [2] Hao Jiming, Duan Lei, Yi Honghong Physicochemistry characteristics of PM10 and PM2.5 from coal combustion [M]: Beijing: Science Press. In Chinese [3] Yang Yijian, Song Hong Toxic effects of PM2.5 on the respiratory system. Journal of Health Toxicology 19(2): In Chinese [4] The environmental protection law of the People s Repubic of China (revised draft) In Chinese [ 5 ] The 12th five-year plan on the energy conservation and emissions reduction. [EB/OL]. In Chinese [6] Yang Xiaodong, Zhang Ling, Jiang Dewang, etc Exhaust gas of Iron &Steel industry and emission characteristics of PM2.5 and pollution control measures. Journal of engineering studies 5(3): In Chinese [7] Xu Tianping, Wang Yongzhong, Xiao Weifeng PM2.5 collection in steel plant and bag-hose precipitation technology. China environmental protection (9): In Chinese [8] Zhen Kuizhao, The mechanism discussion on minuteness dust PM2.5 high-efficiently collected by electrostatic-fabric integrated precipitator. Environmental conformity Assessment 5(6): In Chinese

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