Expert Interpretation | The ultra-low emission transformation of cement contributes to the construction of a beautiful China and the green, low-carbon and high-quality development of the industry
The CPC Central Committee and the State Council attach great importance to the ultra-low emission transformation of the cement industry, and have made important arrangements in documents such as the Opinions of the CPC Central Committee and the State Council on Deepening the Battle of Pollution Prevention and Control, and the Action Plan for Continuous Improvement of Air Quality. Recently, the five departments jointly issued the "Opinions on Promoting the Implementation of Ultra-low Emissions in the Cement Industry" (hereinafter referred to as the "Opinions"), marking the full implementation of ultra-low emission transformation in another industry after coal-fired power plants and the steel industry in China, and will also play an important role in the in-depth governance and green, low-carbon and high-quality development of the global cement industry.
1. Deeply understand the great significance of the ultra-low emission transformation of the cement industry
The cement industry is the third largest industry in China's major air pollutants and carbon dioxide emissions, with sulfur dioxide, nitrogen oxides and particulate matter accounting for 5.6%, 17.1% and 19.3% of the country's industrial emissions respectively, and carbon dioxide emissions accounting for about 13% of the country's total emissions. It is estimated that the full implementation of the ultra-low emission transformation of the cement industry will reduce nitrogen oxide and particulate matter emissions by 500,000 tons and 210,000 tons, and reduce carbon dioxide emissions by more than 10 million tons.
At present, the cement industry has overcapacity, low annual operation rate, and industry profits have declined continuously in the past three years, and will still face pressures and challenges such as weak market demand, further overcapacity, and rising environmental costs in a certain period of time. Through ultra-low emission transformation, we will set a benchmark for green development in the industry, and adopt differentiated environmental management policies, so that enterprises with high environmental performance can truly obtain policy dividends and drive the overall transformation and upgrading of the industry. By encouraging and supporting the development of enterprises that can achieve ultra-low emissions, we can create a fair and just competition, healthy and orderly market environment, solve the problem of bad money driving out good money, and effectively promote the green, low-carbon and high-quality development of the industry.
2. Adhere to the orderly promotion of ultra-low emission transformation in the whole industrial chain
Based on the identification of key emission links in the cement industry, the optimization of treatment technology routes, and the analysis of ultra-low transformation needs and basic conditions in various regions, the "Opinions" put forward the ultra-low emission transformation requirements of the cement industry covering the whole industrial chain, sub-process, and multi-pollutant sub-regional echelon promotion of "raw fuel input-production process-product output".
In terms of organized emission control, the "Opinions" will cover the clinker calcining kiln tail covering nitrogen oxides, sulfur dioxide and 50% particulate matter emissions of the whole plant as the focus of ultra-low emission transformation, and propose that under the condition of 10% of the baseline oxygen content, the emission concentrations of particulate matter, sulfur dioxide and nitrogen oxides shall not be higher than 10mg/m³, 35mg/m³ and 50mg/m³ respectively; For the main dust-producing processes such as cement silos and other ventilation production equipment, the limit value of organized emission concentration of particulate matter is not higher than 10mg/m³, and the national and local standards shall be implemented for ammonia that is not specified.
In terms of fugitive emission control, considering the current uneven level of fugitive particulate matter emission control in the cement industry, the "Opinions" strengthens the requirements for unorganized ultra-low emission control, and puts forward a detailed list of control measures from the perspective of inhibiting the generation of fugitive emissions and their collection and treatment from the perspective of material storage, material transportation, production process and other fugitive emission nodes, and clearly requires that the hourly average particulate matter emission concentration of the main dust-producing points is controlled at 10mg/ Below m³, there is no visible smoke and dust escaping from the dust production point and production facilities, and the factory area is clean and free of dust.
In terms of clean transportation, taking into account the current situation of raw fuel and product transportation and the difficulty of clean transportation transformation, the "Opinions" put forward differentiated requirements, that is, the proportion of raw fuel transportation in clean mode is not less than 80%, and the transportation of products is preferentially in clean transportation mode. For enterprises in key regions, new energy vehicles are used for the part where the proportion of clean transportation of raw fuels does not reach 80%, and new energy or China VI emission standard vehicles can be used in other regions. New energy vehicles are used for transportation in the factory, and new energy is used in principle for non-road mobile machinery, and no corresponding products meet the emission standards of China IV and above. For the promotion of new energy vehicles and non-road mobile machinery, taking into account its sales growth rate and the progress of enterprise transformation, the goal of promoting it in different stages is proposed.
In terms of the transformation schedule, considering that the PM2.5 concentration in Beijing-Tianjin-Hebei and its surroundings and the Fenwei Plain is still 1.5 and 1.6 times the national average, and the proportion of heavy pollution days has reached 2.4 and 2.2 times that of the country, in addition, 7 provinces in key areas have introduced local ultra-low transformation plans, and nearly 40% of the production capacity in Anhui and Henan has implemented organized and unorganized transformation, which has the demand and foundation to take the lead. Therefore, the "Opinions" will advance the timing of the ultra-low emission transformation of the cement industry in key areas, requiring that 50% of the cement clinker production capacity in key areas will be completed in 2025, and the key areas will be basically completed in 2028, and the country will strive to complete about 80% of the production capacity by the end of 2028.
3. Strengthen the integrated promotion of pollution reduction and carbon reduction in the cement industry
In the context of carbon peak and carbon neutrality, the ultra-low emission transformation of the cement industry must pay attention to the synergy of pollution reduction and carbon reduction, coordinate measures such as industrial structure adjustment, energy-saving transformation, and raw fuel substitution, so as to reduce the generation of pollutants from the source, reduce the initial concentration of pollutants and the pressure of end treatment, and at the same time synergistically control carbon dioxide emissions.
Persist in optimizing and adjusting the industrial structure. For new reconstruction and expansion projects (including relocation), we will strictly implement the capacity replacement policy, resolutely curb illegal new production capacity, and build according to ultra-low emission levels. For existing projects, outdated production capacity will be eliminated in accordance with laws and regulations, and enterprises or facilities included in the phase-out and exit plan should no longer be required to implement ultra-low emission transformation.
Vigorously promote energy-saving transformation. Through the promotion of low-resistance cyclone preheater, high-efficiency firing, high-efficiency grate cooler, high-efficiency energy-saving grinding and other technical equipment, the cement industry energy-saving transformation is carried out. Strictly implement the requirements of the energy consumption limit of the cement industry, and clear the clinker production capacity below the energy efficiency benchmark level within the specified time limit, and strive to reach the energy efficiency benchmark level.
Actively promote the substitution of raw fuels. By increasing the proportion of non-carbonate waste residue resources in clinker and the proportion of industrial wastes such as slag and fly ash, we will promote the substitution of raw materials, and through the co-disposal of solid wastes with calorific value to replace coal, encourage the use of clean energy such as natural gas and electricity for drying by independent heat sources, and promote fuel substitution.
Fourth, promote the ultra-low emission transformation of the cement industry with high quality
The ultra-low emission transformation of the cement industry requires time to obey quality. Relevant local departments should formulate ultra-low emission transformation plans for the cement industry in combination with the actual situation, refine the transformation tasks to specific projects, clarify the completion time, and increase policy support. Cement enterprises formulate specific work plans, choose technical routes according to local conditions, and strive to achieve that enterprise leaders really pay attention to it, invest funds, implement real projects, and improve management levels, so as to ensure that the transformation tasks are completed on schedule and with high quality.
Select mature and applicable environmental protection technologies to implement ultra-low emission transformation. The cement kiln is equipped with a low-nitrogen burner, adopts low-nitrogen combustion technologies such as staged combustion and fine control of oxygen content of other decomposition furnaces, adopts selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) and other combined denitrification technologies for kiln tail exhaust gas, and adopts high-efficiency dust removal technologies such as bag type and electric bag composite type for dust removal. We will eliminate the use of treatment technologies such as oxidation that cannot stably reach ultra-low emission levels.
Strengthen the refined environmental management of the whole industrial chain. By strengthening the construction of automatic monitoring, process monitoring and video surveillance facilities, we will improve the level of refined management of the whole industrial chain and ensure that cement enterprises can achieve ultra-low emissions stably. Install automatic monitoring facilities and network with the ecological environment department, install distributed control systems in major production equipment and pollution control facilities, install high-definition video monitoring facilities in key links, build an environmental control platform for the whole plant, and systematically record the operation of monitoring and treatment facilities related to organized emissions and unorganized emissions, as well as clean transportation.
Increase policy support for the transformation of cement ultra-low emissions. From the aspects of reducing off-peak production time, environmental protection tax incentives, independent emission reduction during heavy pollution early warning periods, differentiated electricity prices, credit and finance, etc., formulate and improve the policy system that is conducive to encouraging high-quality ultra-low emission transformation in the cement industry. Air pollution prevention and control funds at all levels will support cement ultra-low emission transformation projects that meet the requirements. Strengthen the supervision and management of ultra-low emission enterprises, and create a fair competition, healthy and orderly development environment.
(The author is Yan Gang, Vice President of the Chinese Academy of Environmental Planning, Ministry of Ecology and Environment)
