Effects on Coagulation to Biogas-Slurry from Cattle Dung
To explore purification approach of anaerobic-digested-slurry from cattle dung, this study translated a technology in inorganic coagulation. Under the same condition, a coagulation experiment was carried out by three kinds inorganic coagulants such as polyaluminium chloride (PAC), aluminum sulfate and ferric chloride, respectively, then measured indicators of pH value, BOD5 value, CODcr value, ammonia nitrogen value, turbidity value. Results showed that there was a varying degree of purification effect, and the removal rate of the above indicators increased as the coagulant dosage increasing, the ferric chloride with the dosage of 960mg/L was the best one in purifying effect among the three coagulants. It is feasible that coagulation technology was used to pretreatment biogas slurry from cattle dung, and most of the indicators reached Chinese national standard basically (GB 18596-2001).