小球藻高效净化猪场废水厌氧发酵沼液研究

Study on the purification of anaerobic digestion effluent of hoggery wastewater by Chlorella PY-ZU1

为了净化脱除养猪场废水厌氧发酵沼液中的主要污染物,本文利用臭氧氧化对沼液灭菌并且降解其中的大分子有机物(效果优于高压蒸汽灭菌法),然后高效培养小球藻转化为生物质变废为宝.研究了通入不同体积浓度CO2以及在沼液中补充部分营养盐对微藻生长净化沼液的影响.当CO2体积浓度从2%逐渐增加到30%时,微藻生物质产量和脱除污染物效率先升后降,并在体积浓度为15%时达到峰值.当沼液中补充添加营养盐10 mg·L^-1磷和1 mg·L^-1铁时,微藻生物质产量相对未添加条件进一步提高了29.1%,达到了5.81 g·L^-1,相应的COD、TN、NH3-N、TP和抗生素替米考星等污染物脱除效率分别提高到88.5%、91.2%、93.6%、98.9%和90.7%.因此,小球藻可高效净化猪场厌氧发酵沼液同时生产高值生物质,具有良好的应用前景.

In order to remove the pollutants in anaerobic digestion effluent of hoggery wastewater, ozonation method was used to sterilize the effluent and degrade macromolecular organics simultaneously. It was proved to be a better sterilization method than autoclave. The sterilized anaerobic digestion effluent was then used to cultivate Chlorella efficiently and the pollutants were transformed to biomass with high value. The effects of CO2 volume concentrations and nutrients supplementation on microalgal growth and pollutants removal were studied. When CO2 volumatric concentration gradually increased from 2% to 30%, microalgal biomass yield and pollutants removal efficiency first increased and then decreased. The peak value reached at the 15% of CO2 volume concentration. When 10 mg·L^-1 phosphorus and 1 mg·L^-1 iron were added into the anaerobic digestion effluent, the biomass yield of microalgae increased by 29.1% to 5.81 g·L^-1. The removal efficiencies of COD, NH3?N, TN, TP and antibiotic tilmicosin increased to 88.5%, 93.6%, 91.2%, 98.9%, and 90.7%, respectively. Therefore, Chlorella can effectively purify the anaerobic digestion effluent of hoggery wastewater and produce high?value biomass at the same time, which exhibits good application prospect.