Evaluation of inhibition relief operations for mesophilic anaerobic bio-liquefaction of lincomycin manufacturing biowaste

Owing to high levels of residual antibiotics, antibiotic manufacturing waste is hazardous to the environment. As a result, such wastes are usually treated by expensive incineration. The high organic content of antibiotic manufacturing biowaste suggests its feasibility for anaerobic treatment, but the presence of ammonia and antibiotics in the waste may be inhibitory factors. After evaluating the peak concentrations of volatile fatty acids (VFAs), ammonia and lincomycin in 10 d bio-liquefaction, different methods for the removal of ammonia from hydrolysate and removal of lincomycin from biowaste were employed to relieve ammonia and lincomycin inhibition respectively. Prior to ammonia elimination on the tenth day, 38.0% of the organic carbon was degraded into hydrolysate. Water replacement, struvite precipitation and nitrogen stripping removed 100, 76 and 30% of the ammonia, respectively. The hydrolysate obtained from the water replacement could be immediately utilized for liquefaction. Lincomycin elution through butanol and water prior to liquefaction removed a large amount of carbohydrate and protein, resulting in poor liquefaction efficiency. The residual lincomycin in the bio-liquefaction process could be co-treated with lincomycin manufacturing wastewater, which made it suitable for the treatment of lincomycin manufacturing biowaste.