The industrial application of water ring vacuum pump is more and more extensive, and the development trend is more and more obvious
1. Large chemical industry
With the development of coal, chemical, pharmaceutical, paper and other industries, filter manufacturers have more and more requirements on water ring vacuum pumps. Before 2000, China could only produce 3-4 water-ring vacuum pumps with a pumping capacity of more than 100m3/min, with an annual output of only a few dozen. In only three years, by 2003, there were more than 10 large pumps with a production capacity of more than 100m3/min (only 7-8 in zibo). According to incomplete statistics, there are hundreds of large pumps with production capacity all over the country. These products are mainly used for:
(1) coal mining industry
As countries continue to strengthen to the coal mine safety requirements, water ring vacuum pumps, especially large water ring vacuum pump has become a necessary requirement of coal industry safety in production. For example, a mining bureau in shaanxi province ordered a batch of pumps of 400m3/ min last year. The min ultra-large water-ring vacuum pumps are used for degasification. Some large coal mines use 7-8 large pumps of more than 100m3/min. With the further strengthening of national security work, large and extra-large water ring vacuum pump will be more and more widely used in coal mine system.
In addition, due to the rapid growth of coal production, vacuum filters for coal washing and coal preparation have also been developed on a large scale. In the 1980s, the sz-4 water-ring vacuum pump had a pumping capacity of 27 m3/min and was mostly used. It was also big at the time. In recent years, coal mine filters have been equipped with large water ring vacuum pumps, pumping capacity of 80-150 m3/min, some have reached more than 200 m3/min, gas volume has continued to increase.
(2) chemical industry
A) chlor-alkali industry
In recent years, Chinese filter manufacturers have launched many large infrastructure and technical renovation projects. The actual subprojects of these projects require a large amount of PVC materials, especially the real estate boom, which further promotes the development of the PVC industry. According to the chlor-alkali industry. Statistics show that China produced 4.1 million tons of PVC last year and imported 200 tons. According to industry forecasts, national demand will reach 8 million tons in 2005 and 15 million tons in 2010. It is because of the rapid growth of demand that China’s chlor-alkali industrial enterprises will continue to expand. In the first two years, many new companies were set up. The development of chlor-alkali enterprises must be equipped with water sand pumps and water ring compressors. The water-ring vacuum pumps and water-ring compressors used to extract and compress acetylene and hydrogen can reach up to 30m3/min with an annual output of 100,000 tons. For enterprises with caustic soda and 100,000-ton PVC, water ring vacuum pump and water ring compressor are required to reach above 70m3/min.
In particular, with the development of the industry, the development and production of high I water ring compressors have been promoted and accelerated.
For a long time, the suction pressure of water ring compressor in China is generally 1 atmosphere or slightly lower than barium pressure, and the exclusion pressure is 0.1mpa, that is, the compression ratio is 2. Some enterprises have produced water ring with pressure of 25 MPaG. Compressor, only 1-2 specifications. In order to adapt to the production of polyvinyl chloride, the former state council major equipment office proposed in the “eight five” major technical equipment project to develop the development of vinyl chloride recovery water ring compressor – an annual output of 4 tons of low polymerization polyvinyl chloride equipment. In the research and development project, the recycling vinyl chloride monomer water ring compressor requires that when the suction pressure is normal or slightly negative pressure, the discharge pressure is o.55-0.6 MPaG and the displacement is 700m3. After several years of efforts, our company passed the technical appraisal organized by the former mechanical department in December 1996, and the customer’s technology met the requirements of emergency repair. On this basis, our company has developed a series of products with a displacement of 90m3/ min-2000m. Per hour. As the equipment is one of the key equipment in the PVC industry, in recent years in the case of large-scale PVC projects in China, the water ring compressor has been promoted and applied, instead of imports.
B) fertilizer industry
Chemical fertilizer industry, phosphate fertilizer production, in particular, is also the focus of the national macroeconomic regulation and control to support industry. As the new project and the old enterprise’s technical transformation is carried out on the above basis, there is also a large water ring vacuum pump. In terms of application, for example, a new large-scale water ring pump developed by a phosphate fertilizer company in yunnan province has a displacement of 300m3/min.
In addition, many phosphate fertilizer enterprise in absolute pressure for 80-100 hPa, need large pumping capacity. For this reason, this paper adopts two-stage water ring vacuum pump and two-stage water ring vacuum pump with air ejector. Under certain working conditions, it has unique advantages. Many chemical fertilizer enterprises have eliminated the vibration noise, high vacuum reciprocating vacuum pump. The two-stage water ring vacuum pump has been reformed and good results have been obtained. It can be said that two-stage water ring vacuum pump will be more and more widely used in the industry.
C) paper industry
The end of last century at the beginning of this century, China’s government debt accounting for a large share of the paper industry. Paper mills across the country have the transformation level and scale, greatly stimulated the development and production of large water ring vacuum pump. One large water-ring vacuum pump (currently a large water-ring vacuum pump in China) is modified at a time, with a pumping capacity of 400IIl3/min and a total power of 400kW. In recent years, as it were, 50% of the pumping capacity of over 100 m3 / min large water ring vacuum pump used in papermaking industry, and this trend is growing.
D) pharmaceutical industry
Vacuum concentration, dehydration, drying and distillation are the main production processes in pharmaceutical enterprises. The technological transformation of pharmaceutical enterprises is also at a higher level and scale, which is more obvious in some large pharmaceutical enterprises. In the past, small pumps of 10m3/min and below were mostly used. At present, in the bidding of these enterprises, large and medium-sized pumps with pumping capacity above 20m3/min have accounted for the majority. In addition, many factories in the pharmaceutical industry used to use two-stage water-ring vacuum pumps with pump displacement of 6-12 m3/min. Now they are equipped with 20-30 m3/min two-stage water-ring vacuum pumps, and some have reached 60 m3/min. A joint-venture pharmaceutical plant in sichuan, for example, bid last year for 10 pumps with a capacity of 60m3/min.
In addition to the above industries, vacuum systems in the food industry, beer industry, metallurgy, power generation, petrochemical, building materials and other industries have been developed on a large scale. For example, an aluminum plant in shandong province has been using multiple water rings for a long time with a pumping capacity of 85m3/min. The vacuum pump and water ring vacuum pump for equipment bidding of last year’s technical renovation project should reach 140m3/min