硝酸钙对深圳河底泥臭味及生物化学特性的影响

Effect of calcium nitrate on odor and properties of chemistry insediment of Shenzhen River

摘要:

为确定合适的硝酸钙剂量,研究了硝酸钙对底泥酸挥发性硫化物(AVS)的控制效果以及底泥总有机碳(TOC)、氧化还原电位(ORP)、pH、含水率、氨氮和生物活性等的变化趋势．结果表明:湿泥硝氮投加量达1.27 g/kg,AVS的去除率在第14天可达97％,其投加量的增加不影响AVS的去除效率,但更高的投加量会使处理效果保持更长的时间;硝氮投加量达1.58 g/kg,底泥ORP可升高至-100 mV;硝氮投加量达2.53 g/kg,底泥pH显著降低;硝酸钙会引起底泥氨氮质量分数增加,降低底泥微生物活性．适宜的硝氮范围为1.58～2.22 g/kg(0.70～0.98 g/g S)．

Abstract:

For the purpose of appropriate nitrate dosage, experiment was conducted to evaluate the performance of control of acid volatile sulfide(AVS) with calcium nitrate and to investigate the changes of related properties including total organic carbon(TOC), redox potential(ORP), pH, water content, ammonia nitrogen and bioactivity. Injection dosage of nitrate-nitrogen at 1.27 g/kg fresh sediment can obtain 97％ removal of AVS in 14 days. There was no affect of increase of nitrate-nitrogen dosage on removal efficiency of AVS, and higher nitrate-nitrogen dosage could keep treatment effect stable for a longer time. ORP increased significantly to -100 mV when injection dosage of nitrate-nitrogen was more than 1.58 g/kg fresh sediment. The nitrate-nitrogen dosage more than 2.53 g/kg fresh sediment resulted in significant decline of pH value, and the nitrate led to increasing in ammonia nitrogen and decreasing in sediment micro-bioactivity. The appropriate range of nitrate-nitrogen dosage is from 1.58 to 2.22 g/kg fresh sediment (0.70-0.98 g/g S).