The calcium carbide industry has become a pioneer in energy conservation and emission reduction

"Under the combined effects of policy constraints, market regulation, and technological advances, the calcium carbide industry is undergoing tremendous changes, and it is expected to eliminate the 'three highs' (high energy, high emission, and high pollution) hats and become a pioneer in energy conservation and emission reduction. "This is the recent expectation of experts such as Sun Weishan, secretary general of the China National Association for Carbide Industry.

Sun Weishan introduced that since 2006, the state has repeatedly issued backward production capacity elimination policies, each time involving the calcium carbide industry, and implement a strict industry access system and increasingly tight differential pricing policies. Up to now, the price of electricity used by the elimination of the category of calcium carbide enterprises is 0.3 yuan/kWh higher than that of the encouraged category, and the electricity price of the restricted enterprises is also higher than the encouraged category by 0.1 yuan/kWh. According to the calculation of the average power consumption of 3,500 kWh per ton of calcium carbide, the implementation of the differential electricity price has enabled the use of large-scale enclosed calcium carbide furnaces and other encouraging enterprises to reduce the cost of ton calcium carbide electricity by 1050 yuan and 350 yuan respectively compared with the eliminated and restricted enterprises.

These policies have accelerated the elimination of the backward production capacity of the calcium carbide industry. Restricting or eliminating the use of calcium carbide-type furnaces, the production of 1 ton of calcium carbide emissions of dust containing exhaust gas is often encouraged more than 20 times the size of large enclosed furnace. During the “Eleventh Five-Year Plan” period, the industry eliminated a total of 3.05 million tons of backward production capacity of calcium carbide, which effectively relieved the contradiction between excess production capacity and the pressure of pollution discharge.

"At the same time as policy pressures, the benefits brought about by the use of resources have also stimulated more calcium carbide enterprises to transform large-scale sealed furnaces and recycle the tailings of calcium carbide furnaces," said Zhang Yu, chairman of Inner Mongolia Baiyanhu Chemical Co., Ltd. After the company's two 33,000-kilovolt closed-off calcium carbide furnaces were put into production, all of the white ash used was burned. With only this one, the coal cost saved in a year exceeds 30 million yuan, while reducing more than 200,000 tons of carbon dioxide.

Yang Lixian, deputy general manager of Ningxia Dadi Metallurgical Chemicals Co., Ltd., said that they used the self-developed dry dust removal, desulphurization and decoking purification technology to make 600,000 tons of sealed calcium carbide furnace tail gas become a baby. At present, the 120,000 ton/year synthetic ammonia, 50,000 ton/year bi-alkanol and 50,000 ton/year polyvinyl alcohol (PVA) units built using calcium carbide furnace tail gas are running smoothly. The utilization rate of calcium carbide furnace exhaust gas reaches 99%. After the 400,000-ton/year closed calcium carbide plant under construction is put into operation at the end of the year, the earth company's calcium carbide production capacity will reach 1 million tons/year, the production capacity of calcium carbide furnace tail gas to ammonia will be expanded to 150,000 tons/year, and the PVA production capacity will be increased by 80,000 tons. /year. Each year, the benefit from the use of calcium carbide furnace tail gas will exceed 500 million yuan, and 470,000 tons of carbon dioxide emissions will be reduced, saving 36,000 tons of standard coal.

Sun Mengjun, chairman of Sichuan Shuncheng Electro-hydraulic Group, told the reporter that their company invested 270 million yuan and is building a 2.55×40000 volt closed carbide furnace. At the same time spend 230 million yuan, supporting the construction of the world's first set of carbide furnace exhaust gas purification dimethyl ether demonstration project. After the project is completed, it can produce 5,000 tons of dimethyl ether, reduce carbon dioxide emissions by 12,000 tons, save 14,000 tons of standard coal, and increase the efficiency of the company by 15 million yuan.

According to another source, Wuhai Junzheng Energy Chemicals Co., Ltd., Shaanxi Fugu Hengyuan Coal Coke Electrochemical Co., Ltd., Henan Pingmei Coal Group and other companies are all in contact with Tianjin Carbon Organic Synthetic Engineering Design Co., Ltd. The company's patented technology will refine the calcium carbide furnace tail gas and produce fine chemical products such as sodium formate, oxalic acid, methanol, acetic acid, acetic anhydride and ethylene glycol to realize the resource utilization of calcium carbide furnace tail gas and high value-added use.

Sun Weishan also revealed that at present, Taiyuan Chemical Group is doing oxygen furnace test. This type of furnace has three major characteristics: First, the capacity of the furnace is large, and the output of single furnace calcium carbide can reach 400,000 tons/year, which is nearly five times the capacity of the largest calcium carbide furnace that can be designed and manufactured in China at present; followed by multi-generation, furnace top Production of carbon monoxide and hydrogen, production of calcium carbide in the hearth, production of ferroalloy at the bottom, direct production of calcium carbide and ferroalloy by coal + oxygen + limestone, less process, full use of energy and resources; again, top gas production, tons of calcium carbide by-product roof gas Up to 3,000 cubic meters, which is 7.5 times that of domestic closed furnaces. It is equivalent to a high-quality, high-efficiency, multi-connected gasification furnace. The coal chemical industry, salt chemical industry, and chlor-alkali chemical industry are closely linked to achieve cross-industry coupling. In order to maximize the use of resources and reduce emissions.

The "Twelfth Five-Year Plan" of the calcium carbide industry indicates that by 2015, the production capacity of calcium carbide in large enclosed calcium carbide furnaces will account for more than 80%, forming 5 to 8 million-ton-grade calcium carbide production bases, and several coal-thermoelectricity (coke)-chemicals (Carbide - Chlor-alkali, other calcium carbide downstream industries) - building materials integration industry base.

“The popularity of large-scale sealed calcium carbide furnaces has provided a reliable basis for the energy conservation and emission reduction of the calcium carbide industry. If the oxygen furnace test is successful, the space for energy saving and emission reduction in the calcium carbide industry will be even greater, and the comprehensive energy consumption per ton of products will be reduced to 1 ton of standard coal. The established targets are expected to be achieved in advance. If more industries such as Xinjiang Tianye and Shaanxi Beiyuan, and other large coal-electricity-electricity-PVC-downstream processing integrated enterprise groups are formed in the industry, the overall energy consumption of the entire industry will also be significantly reduced.” Sun Weishan Say.