The exhaust dust is gone; the tail end of the granulation tower is no longer there

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The exhaust dust is no longer present, and the tail section of the granulation tower has disappeared. Shanghai Jingye Environmental Protection’s third-generation urea granulation tower exhaust purification and recovery system has been successfully applied. In the effort to combat pollution, it is of utmost importance to win the battle to protect the blue skies. Currently, all industries are striving to achieve lower exhaust emissions. To the author’s knowledge, in China’s nitrogen fertilizer industry, over 85% of the exhaust gases from nitrogen fertilizer granulation towers are not purified or recovered, with only a few companies equipped with water-based dust removal systems. The dust content in the exhaust gas after wash dust removal treatment is between 30 and 50 mg/Nm3. It is undeniable that this method is a relatively acceptable approach ； However, in today’s increasingly strict regulations on dust emissions, and over the next five to ten years, it will be difficult to meet the various requirements regarding air pollution control and the reduction of exhaust emissions, especially in key areas such as the Beijing-Tianjin-Hebei region and its surrounding areas, the Yangtze River Delta, and the Fenwei Plain – regions represented by the 2+26 cities. China’s annual urea consumption is around 56 million tons in terms of physical volume, which accounts for about one-third of the global total consumption. Approximately 80,000 tons of urea dust are released into the atmosphere each year; this not only results in significant waste of finished products but also has a considerable impact on the environment. Generally, urea micro-particles settle on the ground within a few kilometers of the urea plant; they not only corrode objects but also harm crop growth, causing the branches and leaves of nearby trees to wither. This contaminates the greenery in the area and undermines clean and orderly production processes, while also posing a threat to the health of people living in the vicinity. To the author’s knowledge, there is now a new production process that serves as an optimized solution for dust recovery from granulation towers; it can effectively promote the recovery of urea dust, prevent environmental pollution, and address the trailing issue associated with granulation towers. Over the past two decades, Shanghai Jingye Environmental Protection Company has been dedicated to promoting and applying ultra-clean emission dust removal systems in the fine chemicals and coal chemical industries. In 2015, boilers across the country entered the era of ultra-low emissions, and the company’s ultra-low emission technology capable of achieving levels below 5 milligrams began to be used on a large scale ； In 2017, in response to the requirements for energy conservation and emission reduction in the fertilizer industry, efforts were made to promote the third-generation high-efficiency purification and recovery system for exhaust gases from granulation towers. To this end, partnerships were established with leading nitrogen fertilizer companies and industry benchmark clients that shared a commitment to social responsibility, such as Henan Xinlianxin Company and Qinghai Yuntianhua Group, in the field of exhaust gas purification and recovery from granulation towers. Since the first set of units came online in March 2018, the measured particulate emissions have been ≤5mg/Nm3. Compared to the water washing dust removal process, this dust removal system improves dust removal efficiency by 84.4% ； Compared to the original direct exhaust method, the dust removal efficiency is increased by over 99.9%. Currently, the emission standards for exhaust gases from granulation towers still adhere to the general standards established 20 years ago, namely GB16297-1996, with a particle emission concentration of 150 mg/m3; it is evident that the standards in this industry are extremely outdated. And 85% of these manufacturers use direct emission methods, making it even harder to meet this standard. It is foreseeable that emissions from nitrogen fertilizer granulation towers will be **designated by the relevant authorities as a key area for improvement. At present, the **\"Emission Standards for Air Pollutants in the Chemical Fertilizer Industry\" (draft for comments) (for nitrogen fertilizers) is still under development. However, due to the backward level of equipment manufacturing in the country, the water washing method commonly used for exhaust gas purification in granulation towers can only reduce the concentration to 30–50 mg/m3, which fails to meet **environmental regulations and trends. Shanghai Jingye Environmental Protection Company’s solution for exhaust gas purification results in particle emissions of ≤5mg/Nm3, which meets the ultra-low and ultra-clean emission standards. It is on par with the emission standards for dust particles in industries such as steel manufacturing and boiler operation. This solution broadens the perspectives of customers, professionals from industry associations, as well as experts and scholars in the field of environmental protection. It will undoubtedly serve as an effective tool for reducing dust emissions from urea granulation towers, providing yet another option available for use. The successful application of Shanghai Jingye Environmental Protection Company’s third-generation exhaust gas purification and recycling solution will provide strong support for the introduction of the \"Emission Standards for Air Pollutants in the Chemical Fertilizer Industry.\" It is hoped that more experts and scholars from environmental protection agencies, as well as clients in the fertilizer industry, will offer valuable opinions and suggestions to improve these technical solutions and drive innovation, so as to contribute to preserving the clear skies and white clouds of our country! Leaders and experts from urea plants who are interested in technical upgrades are welcome to contact me; we can discuss the matter together to develop the best solution tailored for you. Contact: Engineer Lu, WeChat/Phone: 13381830668