Which devices are currently using domestically produced extrusion granulators, and what are the results? Let’s discuss it together

According to Sinochem New Network, on December 16, the plastic plant of Qilu Petrochemical completed the construction of a new high-density polyethylene production facility with an annual capacity of 250,000 tons; the extrusion and granulation unit of this plant’s second high-density polyethylene facility successfully underwent a no-load test run. The granulator used in this facility is the first extrusion granulation unit independently developed in China for large-scale polyethylene (PE) plants. 　　To ensure the successful joint no-load testing of the unit, the factory carried out individual tests on the main motors of the granulator and other key equipment in the unit. It also implemented various optimization measures, such as changing the location of the hydraulic oil pipelines, replacing the connection between the cylinder and the hopper with a flexible connection, and reducing the axis alignment error from 56 microns to 15 microns. After a day of no-load testing, parameters such as the shaft displacement, shaft vibration, and cylinder water temperature of the extrusion granulator all met the design requirements, and the testing was a complete success.

According to Sinopec News Network (Xu Ningsheng), on August 20, the installation and commissioning of the extrusion granulator for Fuzhou Zhongjing Petrochemical’s 350,000 tons per year polypropylene production facility, which was constructed by the Fifth Construction Company of the Refining and Chemical Engineering Group, was completed successfully. The extrusion granulator for the 350,000 tons/year polypropylene plant is the core equipment of this facility, and it is currently the largest extruder produced in China. Due to the large size and heavy weight of the equipment, which posed significant difficulties for installation, the Fuzhou project team of Wu Jian overcame these challenges by organizing the work carefully and planning it systematically. From lifting to installation, experienced experts were brought in to guide the construction process. It took 40 days to complete the installation of the extrusion granulator, and it passed the inspection by relevant experts. At the same time, it has received unanimous praise from foreign experts, owners, and supervisors.

It is reported that introducing a twin-screw extrusion granulation unit with an annual production capacity of 350,000 tons in China requires approximately 12 million US dollars. Based on China’s current ethylene production capacity, 28 large-scale twin-screw extrusion granulation units with a capacity of 350,000 tons per year are needed, at a cost of approximately $450 million. At present, China has 20 large and medium-sized ethylene plants, with an ethylene production capacity of 17 million tons; the actual output is around 14 million tons, ranking the country third in the world. Previously, only 3 companies in Germany and Japan worldwide possessed the capability to design and manufacture complete large-scale twin-screw extrusion granulation units. As the world’s third-largest producer of ethylene, our country lacks its own core technologies, forcing it to rely on imports for key large-scale ethylene production equipment for a long time; as a result, foreign companies monopolize the market and collude to raise prices. 　　In 2007, the **National Development and Reform Commission formulated a special medium- to long-term development plan for the ethylene industry, aiming to accelerate the localization and industrialization of key technologies and equipment in this sector, and to achieve significant breakthroughs and rapid progress in these critical areas. “\"Development of key manufacturing technologies for ethylene plants and equipment production\" has been included in the current list of industries, products, and technologies that are prioritized for development. As the core equipment in the downstream processes of the ethylene production process, large-scale twin-screw extrusion granulation units are an important part of China’s efforts to achieve domestic production of key equipment for large-scale ethylene production. 　　This set of major technical equipment was jointly developed by 6 companies including Dalian Rubber and Plastic Machinery Co., Ltd., with Dalian Rubber and Plastic Machinery Co., Ltd. being the manufacturer. After more than 3 years of concerted efforts by the R&D team, the project to localize large-scale twin-screw extrusion granulation units was finally a great success, filling a gap in China’s industry.

The extrusion granulation unit mixes polypropylene or polyethylene resin with other additives in strict proportions according to the customer’s requirements, and then processes it through mixing, plasticizing, extrusion, underwater granulation, separation, and drying to ultimately produce regular granular products. A large-scale mixing, extrusion, and granulation unit comprises a complete set of highly technical process equipment, including the metering and mixing of resins and additives, extrusion granulation, separation of process water from polymer particles, drying and storage of the granules, as well as the recycling of process water. Due to the high requirements for overall technical standards and the reliability of plant operation, China’s existing large-scale mixing and granulation units in ethylene plants have long relied on imported equipment. In 2010, China’s first domestically produced polypropylene mixing and granulation unit with a capacity of 200,000 tons per year, manufactured by Da Yuan Plastics Company, was put into operation. Subsequently, a polypropylene granulation unit with a capacity of 100,000 tons per year was also brought online at Zhongyuan Petrochemical. However, China has no expertise in the research, development, and manufacturing of polyethylene mixing and granulation units; large-scale polyethylene mixing and granulation units must be imported, and the market for such units is under the control of foreign companies. China’s petrochemical industry has paid a heavy price as a result.

There is still a significant difference in quality between domestic and foreign products. Currently, only Da Yaosu produces domestic versions, but these products have one problem: the equipment often malfunctions. Serious issues such as screw breakage occur from time to time, and there are also many minor problems. Additionally, domestic products are bulky