Study On The Removal Of Typical Pollutants In Animal Wastewater By Anaerobic Self-electrolysis Treatment

A novel technology called anaerobic self-electrolysis(ASE) reactor which can effectively treat wastewater coupled with micro-electrolysis, microbial degradation and bioelectrochemistry technology, accompanied by power generation at the same time. Firstly, odor and ammonia removal from swine wastewater by ASE reactors were explored respectively using real swine wastewater as substrate. Secondly, Power generation and wastewater treatment were discussed when ASE reactors were operated with synthetic swine wastewater containing antibiotics. Consequently, antibiotics concentration treated by ASE reactors were also tested. The main conclusions were as follows:(1) The performance of ASE reactors was studied in terms of electrochemical indexes and water analysis. The maximum stable voltage of 0.527 V(0.503 V of the reactor without catalyst) and the maximum power density of 5.76 W/m3(7.37 W/m3 of contrast) was achieved. Simultaneously, 86.57~87.27% of COD, 51.57~52.90% of total nitrogen, 79.45~84.03% of nitrate nitrogen and 31.03~37.27% of ammonia nitrogen were removed from swine wastewater. The results showed that ASE reactor was capable to treat real swine wastewater effectively.(2) When ASE reactors were operated using swine wastewater as substrate, 11 kinds of odor components were detected by gas chromatography(GC). The results showed that odor components, such as iso-butyric acid, butyric acid, caproic acid and skatole, would be eliminated to 100%, which symbolized odor components of swine wastewater could be effectively removed by ASE reactors.(3) The mechanism of ammonia loss was detected and analyzed via cathodic volatilization, subsequent absorption into an acid solution, the ammonia-oxidizing bacteria(AOB) and anaerobic ammonia oxidation(ANAMMOX) bacteria. The results showed ammonia could be volatilized from cathode with 5.4mg/(d·m2), coinstantaneously, the AOB and ANAMMOX could be detected by FISH. Hence, ammonia could be loss from cathodic volatilization and the degradation by AOB as well as ANAMMOX.(4) By using synthetic swine wastewater as substrate, the performance of ASE reactors and antibiotics removal were explored by electrochemical indexes, water analysis and liquid chromatography-mass spectra(LC-MS) analysis. The voltage of ASE reactors were significantly dropped from 0.51 V to 0.41 V with addition of antibiotics while an increase of the voltage with reduced concentration of antibiotics was noticed. However, COD, total nitrogen and nitrate removal efficiencies were scarcely transformed, ammonia and total phosphorus were obtained better removal efficiencies under antibiotics increment. Moreover, the results of LC-MS showed that antibiotics of synthetic swine wastewater could be effectively removed by ASE reactors, which showed that antibiotics could hinder the performance of power generation but the impact to the effluent quality of ASE reactors was not significant, and the antibiotics could be removed effectively.