| The integrated process whice integrates a series of unit treatment processes, is a high efficient, multifunctional, small land occupied process in wastewater treatment. Therefore it has become the trend of the wastewater treatment, and attracted people much attention in recent years. However, now many integrated equipments of wastewater treatment are simple superposition of biochemical process and separation process such as: precipitation, air floating. So it was limited its application on practical wastewater treatment. In order to broaden its application range and reduce the cost of treatment, the integrated technology of adsorption (reaction)/ precoatingfiltration separation was studied in this article. The quality of effluent was improved by this novel technique, which integrated adsorption (reaction) with an advanced separation, diatomite precoatingfiltration, into a whole.This article was composed of two parts: part one, the integrated technology of adsorption combined with diatomite precoating filtration was used in acid orange II dye removal and organism removal in micropolluted water. The experimental results indicated that organobentonites had obvious effects on dye adsorption, and by circular treatment about 65 min at the dosages of organobentonites 2.0 g·L-1, the filtration rate 2.4 m·h-1, SS is less than 1.8 mg·L-1, the dye removal rate was 90.5 %, COD reduced from 128 mg·L-1 to 25 mg·L-1. The raw bentonite had obvious effects on micropollutants removal. The removal rate of CODMn, UV254, TOC reached 41.4%, 55.9%, 42.1% respectively by the integrated technology treatment. In addition, a model of the circular treatment was developed. The figure caculated by the model matched the experimental figure well for variation of the suspended substance concentration and pressure drops. Therefore, the model is useful for the design of the integrated apparatus and the application of the technology.Part two, the electroplating wastewater included the ion of chromium and copper was treated by the integrated technology of reaction/ precoatingfiltration separation in a laboratory-scale test. The conditions of chemical pro-treatment such as the dosage of reducing agent, pH, and the time of reaction had important roles on efficiency of chromium removal. In addition, the apparent synergistic effect for precipitation reaction in the presence of chromium and copper simultaneity was observed. In result, the removal rate of metallic ions was achieved 99% at pH=7.5. Effects for diatomite precoatingfiltration were also observed. The results showed that the dosage of diatomaceous earth, the quality of influent and flow rate had effects on efficiency oftreatment. In a pilot-plant-scale, the electroplate wastewater from medium and small electroplating plants, which consisted of total chromium (6.72 mg/L), total copper (18.40 mg/L), total cyanide(22.10 mg/L) and COD (240 mg/L), was treated by this integrated technology. The results shows that under the treatment condition of the flow capacity at 10 m3/h, PAM dosage of 3 mg/L, the removal rate for total chromium, total copper, total cyanide and COD reached 93.3%, 97.4%, 99.9% and 75% respectively. Compared with the conventional treatment, this technology was proved to be advantageous over high removal rate for heavy metals, especially for COD. The effluent quality of the integrated process, could meet with the integrated wastewater discharge standard of China. So the integrated technology has a good economy and application prosperity.
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