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Shaanxi Blower Group successfully develops a method for the centralized recovery of high-concentration DMF wastewater. Author/Source: Date: 10-22-2018; Clicks: 57. The purity of the resulting product reaches 99.59%, which should help to completely solve the long-standing problems plaguing the synthetic leather industry. Reporters learned from the Lishui Economic Development Zone in Zhejiang that on October 11th, the project for the centralized treatment of high-concentration DMF-containing wastewater from the synthetic leather industry in this zone was successful in its pilot phase. This was made possible by the use of the latest low-temperature heat pump distillation technology, as well as the MVR steam compressor developed by Shaanxi Blower (Group) Co., Ltd., a device renowned for its energy-saving and environmental-friendly properties. The purity of the DMF produced in this process is as high as 99.59%, while the levels of ammonia nitrogen, total nitrogen, and COD in the wastewater are well below the established emission standards. The successful debugging of this process technology and equipment holds the potential to completely resolve the long-standing problems and challenges associated with the treatment of DMF-containing wastewater, which have hindered the development of the synthetic leather industry. Hu Weiya, deputy director of the Economic Development Bureau of the Lishui Economic and Technological Development Zone in Zhejiang Province, told reporters that the synthetic leather industry is a sector characterized by high pollution and high energy consumption. Our country is a major producer and consumer of synthetic leather in the world, with domestic production capacity accounting for about 80% of the global total, and an annual output value of around 100 billion yuan. The Lishui Economic Development Zone in Zhejiang Province is the second-largest synthetic leather industry base in the country, with over 20 synthetic leather manufacturers and more than 140 production lines. The synthetic leather industry is the key sector driving economic development in Lishui, Zhejiang. Leather synthetic material manufacturers are concentrated in the development zone, resulting in severe environmental problems; at one point, there was even a debate within the zone as to whether environmental protection or industrial development should take priority. According to Hu Weiya, the management of waste generated in the synthetic leather industry, particularly the comprehensive treatment of high-concentration wastewater containing DMF, has long been a major challenge that hinders the survival and development of enterprises. At the same time, toxic and harmful organic solvents such as DMF and toluene are used in the production of synthetic leather. DMF is miscible with water and has a high boiling point, which can lead to residual solvents remaining after processing, thereby increasing the environmental challenges associated with production. Removing DMF, the main pollutant in the wastewater discharged by the synthetic leather industry, has been listed as a key project for improvement in the Lishui Economic Development Zone. Zhejiang Shanggu Energy Development Co., Ltd. is a wholly-owned subsidiary of Shanggu Group. Yang Hongfei, general manager of the company’s project for the centralized treatment of high-concentration DMF wastewater from synthetic leather production, told reporters that in December 2016, Shaanxi Gas Group signed an EPC contract with Lishui Economic and Technological Development Zone to undertake the project for the centralized treatment of high-concentration DFM wastewater from synthetic leather production in that zone. Based on the development of a green circular economy in the Lishui Economic Development Zone, as well as the new demands from synthetic leather manufacturers in the region for energy-saving and environmental protection upgrades, Shanggu Group developed a new domestic treatment process for high-concentration DFM-containing wastewater from synthetic leather production. Utilizing low-temperature heat pump distillation technology as its core, the company designed a distributed energy system solution that combines integrated systems with industrial funds, tailored specifically for the manufacturers in the Shuige Industrial Park. This solution focuses on top-level design and systematic planning for efficient energy use within the park, thereby enabling the proper treatment of DFM-containing wastewater generated by synthetic leather production there. The main raw material for this project is synthetic leather wastewater containing 20% DMF; through recycling and treatment, this wastewater can be discharged in compliance with standards. 388,000 tons of DMF are recovered each year, addressing the issues of improving the DMF extraction rate for users in the synthetic leather industry as well as the treatment of waste materials. At present, the first-phase construction project has been successfully commissioned to produce DMF with a purity of 99.59%, which is well above the design standards; meanwhile, the discharge levels of parameters such as ammonia nitrogen, total nitrogen, and COD in the wastewater are far below the prescribed emission limits. Yang Hongfei explained that this device utilizes a two-tower process consisting of a dehydration tower and a distillation tower to carry out preliminary dehydration of the incoming raw water. Water that does not meet the standards is further treated to remove organic substances within the dehydration tower, so as to ensure it can be discharged in compliance with regulations. Meanwhile, the distillation tower enables the separation of DMF product, residual water, and heavy components, which are then sent to different units for collection and treatment. In addition, the device’s energy system utilizes Shangyu Group’s specialized and integrated energy interconnection island concept, along with its self-developed MVR steam compressors, to convert unusable low-quality heat into usable high-quality heat, thereby enabling the recycling of thermal energy and **reducing the device’s demand for heat sources. Hu Weiya told reporters that the project was successfully commissioned, producing DMF products with a high purity of up to 99.59%. The wastewater discharge levels met standards that are far below those set by the industry; this not only helps to address the issue of total nitrogen in the wastewater generated by local synthetic leather manufacturers but also serves as a model for the transformation and upgrading of the synthetic leather industry in the Lishui Industrial Development Zone. It also results in a significant reduction in the companies’ energy consumption, by around 40%. It offers significant economic, environmental, and social benefits, and will surely play a key role in advancing the development of a circular economy and a green ecosystem in the Lishui industrial park, as well as promoting the green and energy-efficient development of the synthetic leather industry. Li Hongan, chairman of Shaanxi Gas Turbine Group, told reporters that the company evolved from a manufacturer of single products in the field of energy conversion. Through 50 years of continuous innovation in the field of energy conversion, it has evolved into a provider of diversified and international distributed energy system solutions as well as a system service provider. By focusing on distributed energy system solutions, it has promoted the comprehensive development of five key industries: equipment, EPC, services, operation, and finance. Li Hongan explained that in recent years, SHANGGU has kept pace with the requirements for the upgrading of the energy-saving and environmental protection industry as well as the new trends in green development. It has innovatively developed \"specialized + integrated\" energy interconnection island technologies and system solutions. A global operation center for such energy interconnection islands, featuring a nine-in-one energy supply system, has been established in SHANGGU’s Lintong Industrial Park. This approach enables intensive use of land, operational efficiency, functional efficiency, and equipment efficiency, while also improving regional energy-saving efforts and operational management efficiency. Since the operation of the Global Operations Center for Energy Interconnection Islands began, energy consumption has been significantly reduced. In the first half of 2018, the energy consumption per 10,000 yuan of output value was 20.02 kilograms of standard coal per 10,000 yuan, but it has now dropped to 11.4 kilograms of standard coal per 10,000 yuan, representing a 43% decrease compared to the same period in 2017. This has led to a \"green effect\" in terms of energy planning and comprehensive utilization within the industrial park. Currently, the Shaanxi Gear Energy Interconnection Island solution has gained widespread recognition from users in various fields such as synthetic leather wastewater treatment, cogeneration, process industries, integrated complex development, smart cities, and military-civilian integration. At the same time, leveraging its 50-year technical expertise in energy conversion, SHANGGU’s MVR steam compressor reduces energy consumption by over 70% compared to conventional multi-effect evaporation processes.