Research On The Treatment And Recycling Of Industrial Wastewater In Shenzhen City

Under the situation of gradually lacking and polluting of the global water resources, the research on the treatment and recycling of urban industrial Wastewater is of great importance. The intermediate water which was obtained by industrial Wastewater treating has extensive uses. It can be one kind of important non-drinking water, and applies on agricultural irrigation, urban landscape greening, car washing, toilet flushing, industrial cooling water etc. The research on the treatment and recycling of urban industrial Wastewater is an effective method to improve the utilizing efficiency of water resources.Investigated the status of water resources in Shenzhen, and analyzed the reason of water lacking. Combined the investigating data with the developmental trend, forecasted the water supply and requirement from 2007 to 2010 in Shenzhen. The result is, water supply and requirement would be balanced in 2007. But from 2008 to 2010, there would be a lack of water supply. In 2010, the lacking amount of water supply may be 451 million tons.Studied on treating the electroplating Wastewater of Shenzhen by flocculants. The flocculants were produced by a strain of Bacillus mucilaginosus (BM03). Based on the experiments, put forward the effective process. The preliminary research has been taken on the general Wastewater and the Wastewater contained chromium. The experiments showed no matter at acidic or alkaline conditions, the BM03 has improved the water qualities. Especially at alkaline condition, has effectively absorbed the heavy metals.Designed three groups of experiments to treat the general Wastewater, they were respectively added flocculants, NaOH, and the inactive flocculants. The experiments indicated: the flocculants can adjust the pH value by ion exchange and electricity neutralization with their metabolites; moreover, the metabolites formed anionic flocculants, which have larger surface areas. Though the ways of electricity neutralization and adsorption, they can acted with heavy metal ions in a short time; in addition, some parts of microelement may be absorbed by thalli for their metabolism.In order to improve the effect of electroplating Wastewater treatment, designed the orthogonal test. The analysis indicated that the factors concerned with flocculent efficiency were: pH value> static time > dosage of flocculants. The optimum composes of the Wastewater flocculent efficiency is: pH value is 8.5, static time is 8 hours, and the dosage is 10 mL.Combined experimental results with theoretic analysis, put forward the scheme of regenerated Wastewater in Shenzhen. The regenerated Wastewater should be reuse as industry water, urban miscellaneous water and riverway ecological water by two methods, separate reuse and concentrated reuse. To make sure that the regenerated water reaches the standards of intermediate water, we should take on different treating ways accorded to the reuse ways. Compared all kinds of Wastewater treatments, we believe that deal the industrial Wastewater with microbiological flocculants is a nontoxic, harmless and effective way.This research has referenced value to Shenzhen and other cities for the treatment and reuse of industrial Wastewater.