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In this thesis, a traditional SBR process activated carbon removal of nitrophenol wastewater dosing, the PACT process in microbial regeneration of the PAC, initially explored the PACT Process intensification remove the mechanism of action of 3-NP. The study is divided into three parts, one through the PAC of of nitrophenol wastewater static adsorption test to determine the the PAC adsorption equilibration time of 4-nitrophenol adsorption isotherm and the adsorption parameters; through activated carbon nitrophenol removal by test to determine the optimal dosage activated carbon, and compare the PAC-SBR system, the effect of the removal of the effect and impact load GAC-SBR system with of ordinary SBR system nitrophenol; three microbial respiration test obtained microorganisms under different PAC concentrations of total oxygen consumption and the nitrophenol BODresp value, initially explored the PACT Process intensification remove the mechanism of action of 3-NP. Study the following conclusions: (1) PACs separate 4-nitrophenol (3-NP ,4-NP ,2,6-DNP ,2,4-DNP) for adsorption, the adsorption reaction is carried out in the first 30min substantially reach equilibrium; PAC when the nitrophenol PAC quality in the ratio of 0.2 to 1, 4-nitrophenol adsorption on the PAC meet Langmiur adsorption model, calculated adsorption model under Langmiur, a separate 3-NP ,4-NP, 2,6-DNP ,2,4-DNP adsorption saturation adsorption capacity Qm order 309.6,316.5,609.8 and 675.7 mg / g. (2) the adsorption amount and adsorption capacity of the inactivation of activated sludge per unit mass of 4-nitrophenol is far less than the PAC. Colloidal substances in the activated sludge occupy the adsorption sites on the PAC, PAC and untamed inactivated activated sludge co-adsorbed molecular nitrophenol competition PAC on 4-nitrophenol saturated adsorption capacity decreases. (3) In the high impact load, to the reactor dosing PAC and GAC removal capacity of the system can be improved to 3-NP and 2,6-DNP, the higher the concentration of activated carbon and cast plus strengthening removal effect more obvious. According to the results of this study, when the 3-NP initial concentration of 350mg / L, the PAC the best dosage of 600mg / L; 2,6-DNP initial concentration of 60mg / L, PAC cast plus the amount of 400 mg / L. PAC-SBR systems are better than two nitrophenols removal, effluent color, activated sludge settling and activity, as well as the impact load capacity of GAC-SBR system and ordinary SBR system. (4) to the two nitro-phenol (3-NP, and 2,6-DNP) as the sole carbon source, in a certain concentration range, nitrophenols the higher the concentration, the higher total microbial oxygen consumption, respiratory rate, the more strong. Test 3-NP and 2,6-DNP relative oxygen consumption measured BODresp were 0.9355 and 1.3139. (5) PACT Process intensification removal process is not a simple combination of adsorption and biodegradation of 3-NP, but micro-organisms and PAC mutually reinforcing synergy. When the high initial concentration of 3-NP, PAC 3-NP adsorption, reducing the toxic effects of 3-NP microorganisms, the microorganisms maintain a high activity; Meanwhile, the biological regeneration of the microorganisms on the PAC so that the PAC vacated portion adsorption sites, you can re-adsorption of organics. In adsorption - degradation - regeneration - re-adsorption removal of 3-NP in this synergy can be improved. PACT process to remove the 3-NP process, wherein the microorganism of PAC due to the concentration gradient and the microbial bio-regeneration PAC strengthen the activated sludge system, the average of the 3-NP in the PAC resolution rate reached 76.95 ± 8.5%; biological regeneration rate of greater than 19.93%.
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