In power plants and semiconductor indust€ries, the requirements for pure water are high.The dissolved carbon dioxide in water will affect th∏e water quality. Removing carbon dioxide before the EDI p≥rocess of primary pure water can increase the produced water quality from 1.0 λMΩ to 18.0 MΩ, which can greatly improve the silic←on and boron removal rate of EDI produced water, reduce the pressure of terminal polishing mixed bed, and greatly improve the terminal water quality.
In particular, pure water for industrial semicond♦uctor wafers over 8 inches has higher requirements for the content of silic↑on and boron in water. That is because when pure water is use≈d to clean the silicon wafers, the silicon in the water will be deposited on theδ surface of the silicon wafers, which will affect the quality of the thermal oxide layer, produce ↓surface defects, and reduce the yield of devices. In order to make αthe terminal pure water quality meet the production requ&irements, it is necessary to strictly control the content of silicon and bor↕on in the water at the primary pure water end. Otherwise, it would be difficult for the termi≥nal polishing mixed bed to produce water that can meet the production req£uirements.
The pharmaceutical industry also needs ultra$-pure degassed water, because the dissolved gas will affect production¥ efficiency and product quality. At the same time, the pharmaceutical industry needs t₽o control the carbon dioxide in process water at a very lφow level in order to control the conductivity and PH value of water.
The degassing membranes can reduce carbon dioxide in ©the water used for production processes in the semiconductor and phar©maceutical industries, reducing the concentration of carbon dioxide to improve the efficien•cy of the electrodeionization process.
The method of removing carbon dioxide in water by a mαembrane is to let water flow in the hollow fiber memb>rane tube and change the pressure of gas outside the tube, such as ®reducing the solubility of oxygen and carbon dioxide in water by negative pressure o↓r pressurization (adding pure N
2, etc.) to achieve the removal effect.
This is a new application of membrane ©separation technology and a novel gas/liquid membrane separation proc"ess. According to the different decarburization accuracy requiremen☆ts, three different operation modes of vacuum pumping, air purging, or vacuum pumping + ®air purging can be used to remove the dissolved carbon dioxide in the water down to© 0.5 ppm.
At the same time, the degassing membrane can not only remove c©arbon dioxide from the liquid but also add carbon dioxide to the liquid w☆ith precision and predictability. In semiconductor p€roduction, ultra-pure water should be used to avoid chip conta$mination since water is used for lubrication, cooli•ng, and debris washing in the grinding wheel scribing process. Usual♥ly, it is necessary to inject a small amount of high-purity carbon dioxide gφas into the water for foaming to reduce electrostatic damage, but the €amount of carbon dioxide should be controlled. The use of de<gassing membrane added to the process flow can ensure the accurate expected conceδntration, and improve the scribing effect, thus saving time and simplifyβing the production process.
Since the establishment of Guochu Technoloγgy (Xiamen) Co., Ltd., we have taken membrane separation technology as our core and are committed to promoting new separation technology.
We will continue to explore new applications of the new deg$assing membrane technology in the fields of food, dairy, beverage, microelectronics, m≈etallurgy, chemical industry, machinery, and environment to provide more users w<ith professional gas separation solutions.
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