Selection of liquid ring vacuum dechlorination pumps
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This post was last edited by sunjl1981 on 2013-1-6 at 22:42. Our company is planning to build a project with an annual production capacity of 360,000 tons of caustic soda, and for the dechlorination process, liquid ring vacuum pumps will be used. We would like to discuss whether it is better to use imported vacuum pumps or domestic ones. From our research, foreign companies that can supply water ring vacuum pumps include Xihe Pump Industry, Asahi Kasei, Hydramatic, Nasim, etc. In China, only Xi’an Pump Valve Factory produces such pumps, but on a small scale; there are also companies that are now working on producing them on a larger scale, though it’s not clear what the quality of their dechlorination performance is like. Please share your experiences in this area. # &
The liquid ring vacuum pump used for dechlorination is different from ordinary water ring vacuum pumps; it comes into contact with chlorine, and its liquid ring consists of chlorinated water, which imposes high requirements on the corrosion resistance of the vacuum pump. Domestic vacuum pumps are slightly inferior to imported counterparts in terms of sealing performance and corrosion resistance (after all, they started developing their machinery industry earlier than we did), so it is recommended to use imported equipment.
There is a company in Dalian that can manufacture such dechlorination vacuum pumps; it uses foreign technology acquired through academic research, and that company is Dalian Kehuan Pump Industry. :handshake
A design institute once recommended Asahi Kasei’ s products, as they are more reliable to use compared to those made in China. It’s tough for domestic products. :Q
In the first phase, our company used pumps supplied by Japanese company Asahi Kasei; in the second phase, we used domestically produced titanium water ring pumps from Xi’an Pump Valve. Imported equipment is much more expensive. In imported pumps, the motor and the pump are connected by belts, and over time these belts wear out, which affects performance. Therefore, it is necessary to regularly inspect and adjust the belts.
Our company is Foshan Water Pump Factory Co., Ltd. in Guangdong Province, with a history of producing vacuum pumps spanning over 50 years. It was originally German Siemens technology; later, we carried out independent research, development, and improvements based on it, and the supporting technologies for the chemical industry have now become mature. For the absorption of chlorine gas, our company uses 98% concentrated sulfuric acid as the working fluid for the water ring pump. The maturity of this technology has been verified at Binzhou Chemical Group. Imported pumps are expensive, difficult to repair, and their service support is surely not as fast as that of locally produced pumps, right? ? Hehe
Should you install one dechlorination system for those 360,000 tons? Personally, I recommend installing two dechlorination systems to make control easier. Two domestic vacuum pumps will suffice; even if a complete set is used, domestic vacuum pumps can be employed. According to Xi’an Pump and Valve, they have SK40 models that can be used with vacuum pumps for 400,000-ton capacity caustic soda production. For our smaller-scale projects, we have inquired about the prices of imported vacuum pumps, and they are more than twice as expensive as domestic ones, not to mention the tax costs, and the delivery time is also longer. I still personally believe in supporting domestic products; after all, **everyone is contributing to the development of the national manufacturing industry. Although domestic products have their shortcomings, they are still developing, and it’s acceptable for them to have imperfections. If no one buys domestic products, then there will be no such products anymore. You’ll have to pay whatever price foreigners demand; if they refuse to sell them to you, what can you do? People often say that domestic products face difficulties, but it also has a lot to do with the consumption habits of Chinese people and........ So, it’s really tough for domestic products! :L