Part.1
What is the background for the introduction of the standard?
The “Opinions of the Central Committee of the Communist Party of China and the State Council on Deepening the Battle Against Pollution” clearly states that during the 14th Five-Year Plan period, efforts should be made to strengthen the coordinated control of fine particulate matter (PM2.5) and ozone. Nitrogen oxides (NOx) are important precursors for the formation of PM2.5 and ozone, and are a binding target during the 14th Five-Year Plan. The lime and calcium carbide industries are both high-energy consumption and high-emission sectors, and are significant sources of particulate matter and NOx emissions. In 2021, China’s lime industry produced approximately 310 million tons, accounting for about 72% of the world’s total production, mainly distributed in provinces such as Hebei, Shandong, Guangdong, Guangxi, Zhejiang, Fujian, Sichuan, Jiangsu, Jiangxi, and Hunan. China is the only country in the world that produces polyvinyl chloride (PVC) on a large scale using the calcium carbide method; in 2021, China’s calcium carbide production capacity reached 38.5 million tons, exceeding 97% of the world’s total production capacity, with a production of 30 million tons, mainly concentrated in the northwest region.
Currently, lime and calcium carbide enterprises are subject to the “Emission Standards for Air Pollutants from Industrial Furnaces and Kilns” (GB 9078—1996) and the “Comprehensive Emission Standards for Air Pollutants” (GB 16297—1996), which have poor industry specificity and face certain issues during implementation, such as the lack of specified emission limits for NOx and requirements for managing unorganized emissions. To further standardize the management of pollutant emissions in the lime and calcium carbide industries, fill the gaps in emission standards for key industrial furnaces and kilns, and implement precise, scientific, and lawful pollution control, it is necessary to formulate emission standards for air pollutants in the lime and calcium carbide industries to further regulate the industry’s emission management.
Part.2
What are the characteristics of this standard in emission control?
This standard adopts a problem-oriented and precise policy approach, adhering to the systematic governance concept of controlling the entire process from source reduction, process control to end treatment, with a strong industry specificity.
(1) Strengthening source and process control, standardizing management of unorganized emissions
Unorganized emissions are a key difficulty in controlling air pollutant emissions. The standard implements comprehensive supervision of unorganized emissions based on industry characteristics. It sets clear control measures for unorganized emission links, such as the storage, transfer, and transportation of materials like carbon materials, limestone, and raw coal, as well as process procedures. Additionally, the standard proposes suggested values for monitoring concentration limits of particulate matter within the plant area, which local authorities may implement based on local environmental protection needs to monitor unorganized emissions. Through these control measures, comprehensive management of unorganized emissions is achieved.
(2) Combining control of major pollutants and characteristic pollutants to improve organized emission control
This standard is based on an analysis of pollutant production and discharge during the mining, lime manufacturing, calcium carbide production, and lime product production processes, differentiating between production processes or facilities such as lime kilns, drying kilns, crushing, screening, and grinding, and specifies applicable organized emission limits. To comprehensively manage air pollutant emissions while simplifying pollutant control projects, it adopts the form of “major pollutants + characteristic pollutants” to ensure stringent emission supervision. Major pollutants include particulate matter, sulfur dioxide, and nitrogen oxides; characteristic pollutant indicators reflect the concept of classified control, identifying toxic substances like hydrogen cyanide based on health risks and odor substances like ammonia based on odor control.
(3) Optimizing control indicators, encouraging the adoption of advanced production processes
Vertical drying kilns have advantages such as good energy-saving effects and low carbon material breakage rates. However, due to low-temperature drying requiring a large amount of cold air, the oxygen content in the exhaust gas is relatively high. Therefore, compared to the baseline oxygen content of 16% for other kiln types, the standard sets the baseline oxygen content for vertical drying kilns at 18%, addressing the bottleneck for the promotion and application of vertical drying kilns and ensuring scientific control of the standard.
Part.3
How feasible is the implementation of the standard?
In recent years, relevant local standards have been introduced in key areas such as the Beijing-Tianjin-Hebei region and the Yangtze River Delta. Lime and calcium carbide enterprises in these areas have already begun upgrading and transforming their process equipment and environmental protection facilities, accumulating mature cases of compliance technology, laying a technical foundation for the implementation of the standard. Industry associations and relevant experts unanimously believe that this standard can reflect industry concerns, has strong guidance and operability, and there is an urgent hope for the standard’s introduction. After the implementation of the standard, some enterprises will need to upgrade and transform facilities for controlling unorganized emissions of particulate matter during material storage, transfer, transportation, and process procedures. A small number of enterprises will need to upgrade their kiln flue gas treatment facilities, which will correspondingly increase production costs, but will not produce a contraction effect on supply or demand, remaining at an industry-acceptable level. During the formulation of the standard, public opinions were solicited, and there was full communication with industry associations and relevant enterprises, with market expectations already established, and related enterprises have begun preparing for transformation work. Existing enterprises will implement this standard from July 1, 2024, providing sufficient time for enterprises to upgrade and transform.
Part.4
What are the environmental and social benefits of implementing the standard?
The implementation of the standard has good environmental benefits, positively impacting the improvement of air quality and meeting the public’s demand for a good ecological environment. Implementing this standard will further promote fair competition in the industry, effectively solve the problem of “bad money driving out good money,” and help establish a more equitable and orderly market environment. Additionally, it will raise the environmental access threshold for new, modified, and expanded projects in the lime and calcium carbide industries, enhance the pollution control levels of existing enterprises, promote the optimization of fuel structures, combustion technologies, and kiln structures, reduce energy consumption, and advance the synergistic effect of pollution reduction and carbon reduction, contributing to the green and high-quality development of the industry, achieving a win-win situation for environmental and economic benefits.
Strive to Build a Beautiful XinjiangSource丨Ministry of Ecology and Environment Reviewed by: Liu Xin Edited by: Shi Jianqiang Edited by: Wang Zehao Editor: Wang Zehao
