| A new technique of treating wastewater from TCM industry based on two-phase anaerobic-aerobic theory is presented in this paper, which is abbreviated to TPAD-O system. The system's capability of treating wastewater with high concentration and tinting strength, treatment efficiency, change in microorganism species and treatment characteristics have been studied, hi addition, this technique is tentatively used in a pilot scale test with a treatment capability of 150m3/d.The experiment art is phased through controlling volumetric loading in combination with chemical method; i.e. according to the determined volumetric loading parameters and chemical method, a certain amount of CCl4 is added to limit the acid-producing reactor to acid-producing phase so that methane-producing bacteria can keep highly active.The fundamental conditions of rapidly starting the two-phase anaerobic reactor are studied. The experiment results show that when the value of pH is within 4.5-6.0, temperature 27 2 and organic loading Ikg/m3.d~10kg/m3.d, starting reactor is relatively easy.The experiment results of TPAD-O applied to treatment of TCM wastewater of high concentration with its loading at 7~19kgCOD/m3-d show that the removal efficiency of TPAD-O is generally staying at 90% and the concentration of COD contained in treated wastewater is below 400mg/l; so TPAD-O boasts an conspicuous high removal efficiency and stable performance compared with traditional anaerobic techniques.The optimum working conditions of acid-producing phase with two-phase anaerobic-aerobic technique is as such: temperature, 15~35 ; pH,4.5~6.5; organic loading, 4~20kgCOD/(m3-d). Generally speaking, the efficiency of removing COD of acid-producing reactor is kept within 25~35 %.The analysis of organic pollutants contained in wastewater in the process of treatment by using CC-MS shows that the degradation of organic matters in acid-producing reactor is just a pre-treatment to some degree, organic matters are not completely degraded in the course of acid production, but their morphological properties are altered, matters consisting of big molecules are changing into onescomposed of small molecules, which, previously defying biochemical treatment, can be biochemically degraded. As a result, some organic materials, not easily detected with BOD5 because of their existing form of COD, can be decomposed into some matters subject to easier detection with BOD5 in the process of acidification, which will notably increase the ratio of BOD5 to COD.The microscopy of sludge producing methane shows that there exist 8 species of bacteria such as methane-producing bacterium, sarcinene bacterium etc. The diameter of grain comprising sludge is within 0.3 ~ 0.6mm, and varieties of microorganism species are living on the surface of sludge grain.The experiment results of pilot scale test with a treatment capacity of 150m3/d, the COD volumetric loading of acid-producing reactor at 6.4kgCOD/(m3-d), the BOD5 volumetric loading at 2.89 kgBOD5/(m3-d); the COD volumetric loading of methane-producing at 2.4kgCOD/(m3-d), the BOD5 3.2 kgBOD5/(m3-d); the aeration basin stuffed with soft stuffing, its COD stuffing volumetric loading at 1.3 kg COD/(m3-d), its BOD5 1.1 kgBOD5/(m3-d), show that TPAD-O is applicable to the treatment of wastewater from TCM industry and the study in this paper is playing pioneer for the large-scale industrial application,...
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