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Exploring Paths for Technological Improvement in the Nitrogen Fertilizer and Methanol Industries / Author/Source: Sinochem New Network / Date: 2019-07-12 / Clicks: 9. More than half of the period covered by the 13th Five-Year Plan has passed, and China’s nitrogen fertilizer and methanol industries have made significant progress by actively changing their development models, optimizing their industrial structures, and shifting to new sources of growth momentum. At the 2019 China Nitrogen Fertilizer and Methanol Technology Conference, held last week under the auspices of the China Nitrogen Fertilizer Industry Association and co-organized by Haohua Junhua Group Co., Ltd., experts attending the conference noted that in the future, it is necessary to rely on clean gasification and safe, environmentally friendly technologies to steadily improve the production technology levels in China’s nitrogen fertilizer and methanol industries. Continuous breakthroughs in clean coal gasification technology \"As a core component of coal chemical projects, clean coal gasification technology has seen continuous advancements in recent years. Thanks to this technology, China’s nitrogen fertilizer and methanol industries have entered an important period characterized by changes in raw material structures, green and cleaner production methods, as well as structural adjustments within these industries; the pace of expansion, refinement, and diversification in these sectors has accelerated significantly.\" ”Gu Zongqin, president of the China Nitrogen Fertilizer Industry Association, said. “Based on the atmospheric pressure batch moving bed gasification technology, Junhua Group has developed a high-temperature slag-free pure oxygen continuous gasification technology along with the corresponding equipment, tailored to the needs of small and medium-sized coal chemical plants and the ammonia synthesis industry for the upgrading of their gasification units, as well as to meet the market demand for coal-based industrial gas. This enables an upgrade of gasification technologies and equipment, thereby enhancing the competitiveness of coal chemical enterprises. ”Wang Enwei, deputy chief engineer of Junhua Group, explained that the investment required for this facility is 10% to 20% of that needed for fluidized bed gasification, while its production costs are two-thirds of those associated with fluidized bed technology. This approach helps to address the funding challenges faced by existing small fertilizer and gas production enterprises in carrying out technological upgrades; moreover, this facility does not generate any waste materials. According to Du Guoqiang, deputy chief engineer of Aerospace Changzheng Chemical Engineering Co., Ltd., the space furnaces they have designed feature a complete set of key technologies and equipment development systems for powder gasification. These furnaces can be used with China’s typical lignite, bituminous coal, and anthracite, and they meet the needs associated with the upgrading of traditional coal chemical industries as well as the industrial development of modern coal chemical processes. Recycling urea dust to reduce emissions and improve efficiency: In the urea industry, granulation towers are commonly used in China to cool and shape molten urea as it falls, which results in exhaust gases containing urea powder; this not only pollutes the environment but also leads to losses in efficiency. It is estimated that a granulation tower with an annual urea production capacity of 400,000 tons emits 720 tons of urea dust per year. If this amount of urea is recovered, it not only brings environmental benefits but also increases the urea production volume. “We have developed a recovery unit for urea granulation towers that utilizes a cross-flow high-efficiency packed scrubber. It makes use of the natural ventilation of the original tower, without the need for additional forced ventilation systems; these systems are installed inside the top of the granulation tower. The operation is simple, and it is integrated with the production system. Once the urea concentration in the absorption liquid reaches a certain level, it can be returned to the production system for reuse. ”Liu Jincheng, vice chairman of Hebei Yangquan Zhengyuan Chemical Group Co., Ltd., said. Unlike the wet dust removal process developed by Zhengyuan, Shanghai Jingye Environmental Protection Energy Technology Co., Ltd. has developed a dry dust removal process. “The high-efficiency exhaust gas purification system for tower granulation developed by us can eliminate the trailing phenomenon, with an outlet dust concentration of 5–10 mg/Nm3, meeting ultra-low emission standards. Moreover, urea dust can be recycled, improving the raw material conversion rate. ”Zhou Lie, chairman of the company, said. “In addition, to address the issues of sludge, wastewater, and aerosol emissions generated by the low-pressure coal gasification process in our country, we have also developed a multi-pollutant treatment system for low- and medium-pressure coal gasification. ”Zhou Lie said that by using dry methods to capture dust, salts, tar, and aerosols from the gas, the cleanliness of the water used in the gas generation process can be brought to an excellent level. The waste residues are reused in combustion to recover thermal energy, and there are no secondary pollution sources during this treatment process. Four measures for comprehensive control of VOCs As a key industry for VOCs control, Wen Qian, the deputy chief engineer at the Petroleum and Chemical Industry Planning Institute, suggests that the nitrogen fertilizer industry can take action in four areas to carry out comprehensive management of VOCs. First, deepen LDAR efforts by strictly following the provisions of the \"Guidelines for Leak Detection and Repair in Petrochemical Enterprises\", establishing records, and carrying out tasks such as leak detection, repair, quality control, and record management. Second, it is necessary to strengthen equipment inspection, including the inspection of backup pumps, operating pumps, control valves, mixers, and open pipelines, in order to enhance quality control; the sealing points of VOCs treatment facilities and storage tanks should also be included in the inspection plan. Third, strengthen the collection and treatment of VOCs in the circulating water system; existing enterprises in key areas should gradually replace open-based collection methods such as drains, ditches, canals, and wells with measures such as the use of sealed pipelines. Fourth, increase efforts to upgrade wastewater collection and transportation systems, and comprehensively strengthen the collection and treatment of high-concentration VOCs emissions from wastewater systems. Collection wells/pools, regulating tanks, oil separation tanks, air flotation tanks, concentration tanks, etc., should employ sealed processes or closed-collection measures, along with efficient pollution-control facilities such as combustion furnaces. Low-concentration VOC-containing waste gases from biochemical tanks, aeration tanks, etc., should be collected in a closed manner and subjected to treatments such as deodorization to ensure compliance with emission standards.