Treatment For Terramycin Bacterial Residue By Protein Recovery-Anaerobic Digestion

The reduction,reclamation and harmlessization treatment for antibiotics bacterial residues,a hazardous waste,has been a serious problem for the pharmaceutical industry.Based on the analysis of the main pollution characteristics of terramycin bacterial residue?TBR?,the test for protein extraction and separation from TBR were carried out,then anaerobic digestion for the remaining residue was studied.At the same time,the optimal technology and the best operating parameters was determined.The main conclusions are as follows:1)Thetechnologyofacid/thermal,alkali/high-pressure-homogeneous,alkali/ultrasonic were used for protein extraction.The results showed the best technology for protein extraction from TBR was alkali/ultrasonic technology.By measuring the dissolution rate of proteins in the solution,the best condition for protein extraction by alkali/ultrasonic technology was determined.With the optimum condition,when moisture content was 97%,pH was 13.0,sound energy density was 7.5 W·mL^-1,and reaction time was 30min,the concentration of protein increased to 19 710.94mg·L^-1,and the dissolution rate of proteins was 84.11%.2)The technology of isoelectric point precipitation,ethanol precipitation,ammonium sulfate precipitation was used for protein separation.The results showed the best technology for protein separation was isoelectric point method.By measuring the precipitation rate of proteins in the solution,the best condition for protein extraction by isoelectric point technology was determined.With the optimum condition,when pH was5.0,the remaining protein concentration in the treatment solution was 325.23 mg·L^-1,and the precipitation rate of protein was 98.35%.The results showed a protein content of 0.83 grams per gram of precipitate,and the content of copper?Cu?was 125 mg·kg^-1204 mg·kg^-1.The content of chromium?Cr?content was less than 10 mg·kg^-1,the content of cadmium?Cd?was 0.18 mg·kg^-10.63mg·kg^-1,arsenic?As?content of less than 0.9 mg·kg^-1,residual terramycin content of 3 601mg·kg^-1.3)The results of anaerobic digestion of the untreated TBR shows that organic loading rate was 0.4 kgCOD·m^-3·d^-1,biogas production rate was 142 L·kg^-1COD·d^-1,and COD removal rate was 93%.The results also show that the treated TBR organic loading rate was 0.4 kgCOD·d^-1,biogas production rate was 336 L·kg^-1COD·d^-1,and COD removal rate was 96.8%.The biological anaerobic digestion characteristics of TBR were significantly improved by protein separation and recovery...