A case study of long-term RO plant operation without chemical pretreatment

Described herein is a case study of long-term reverse osmosis (RO) plant operation without applying chemical pretreatments to the feed water. This project was undertaken with the financial support from the Department of Bio-Technology, New Delhi, and the work was carried out by a research team from Central Salt and Marine Chemicals Research Institute (CSMCRI), Bhavnagar (Gujarat), India. A prototype plant with a 30,000 L/d capacity was designed, manufactured, installed and operated at the village of Mocha-Gorsar, located in the Porbandar district, to provide drinking water. The village was to be developed as a model Bio-Village where other projects related to village problems are also operated by other research institutes. Thin-film composite (TFC) membrane-based RO technology was indigenously developed by the institute for treatment of brackish water and waste water for the first time in India; it was used successfully in this plant, which gave a typical NaCl rejection of about 95%. This is a typical case study of RO plant installation where physical methods of pretreatment such as sand and micron cartridge filters were used; no chemical pretreatment of feed was employed for long-term brackish water desalination study. The idea was to avoid the usage of chemicals, which concentrate in the effluent water, might affect the environment and may not suit the village community. Plant performance during 24 months of continuous operation with respect to variable feed salinity, membrane cleaning and regenerations is discussed.     

某市工业用户燃气具改造的环保意义

为了使天然气在工业中得以推广，对某市几种常用燃料及其支柱工业的燃料使用情况进行了调查研究。通过理论分析及数据归纳得出：如果能够推广和有效使用天然气，将在环境保护及经济上得到效益。     

空化水射流清洗的实验研究

本文在理论分析空化射流清洗机理的基础上，通过实验研究了基于自激振荡空化喷嘴产生空化射流，从而提高射流清洗效果的新型清洗方法，并实验研究了将该方法用于管道内壁清洗时，改善清洗效果的措施。     

清洗高洁净度设备工程技术——以多晶硅工艺设备清洁为例

在电子制造及其它一些高新技术行业,对设备的洁净度要求都非常高;以多晶硅提纯装置的清洁工程为实例,阐述了高洁净度设备清洗系统的工艺流程与操作方法.     

电子组装中PCBA清洗技术

清洗对于电子产品可靠性有着非常重要的影响,针对印制电路组件污染物进行了系统阐述,并对不同的清洗技术和工艺进行了总结归纳,讨论了影响清洗效果的各个因素及其检验规范,为实际生产起到了指导性作用。     

新型捕收剂R31浮选低品位白钨矿的研究

用R31为捕收剂、Na2CO3为调整剂、Na2SiO3为抑制剂进行白钨粗选,白钨精选采用Na2SiO3加温浮选的工艺,在原矿含WO30.28%的小型试验中,获得白钨精矿品位73.10%,回收率81.67%,试验表明,R31是白钨矿较为合适的捕收剂.     

一次清洗剂 HEDP 的试验研究

主要探讨ＨＥＤＰ对热力设备的清洗性能,一次清洗钝化效果,为提高化学清洗效率,改善劳动强度,降低清洗成本、缩短清洗周期、减少环境污染开辟新途径。     

等离子体清洗同步辐射光学元件

同步辐射光束线的光学元件的碳污染问题.它导致光学系统的光通量下降,尤其是在碳吸收边情况更加严重.因此在光束线运行一定的时间后,必须对光学元件的碳污染进行清洗以便保证其正常使用. 为此我们开发了一套射频等离子体原位光学元件清洗系统,以干燥的氧气和氩气为介质.在产生的等离子中存在大量的臭氧,与光学元件表面的碳反应,变成CO和CO_2气体,从而达到清洗的目的.实验证明等离子体清洗不但可有效清除碳污染,而且有利于光束线真空系统的超高真空环境的恢复,为光束线的维护提供了方便.     

Optimisation of Bacillus cereus biofilm removal in the dairy industry using an in vitro model of cleaning‐in‐place incorporating serine protease

This article addresses a major hygienic issue in the dairy industry, namely biofilm removal. Response surface methodology was deployed to optimise Bacillus cereus biofilm removal conditions using serine protease. The currently practiced alkali cleaning‐in‐place (CIP) method was also optimised, and while the optimised protease CIP resulted in complete removal of biofilm cells, the reference CIP (with alkali) resulted in a reduction of 4.08 log biofilm cells/cm² and the optimised alkali CIP resulted in a reduction of ～4.92 log biofilm cells/cm². Furthermore, the amount of the biofilm matrix removed in the optimised protease CIP was significantly higher than that of alkali CIP. It was concluded that the optimised protease CIP has better applicability.