Effect of different particle sizes of zero-valent iron (ZVI) on H2S and CH4 emission in sewage sludge
不同粒径零价铁(ZVI)对污水污泥H2S和CH4释放速率的影响

Effects of different particle sizes of zero-valent iron(ZVI),i.e.200mesh-iron(200m-ZVI),800mesh-superfine iron(800m-ZVI) and nanoscale iron(nZVI,d=20 nm),on the H2S and CH4 emission in sewage sludge were investigated.The result shows that in the presence of 0.1% 200m-ZVI,the H2S average emission rate increased by 48%.However it decreased by 33.1% and 77.1% in the presence of 0.1% 800m-ZVI and nZVI in sewage sludge respectively in the experiment of 22 days duration.Methane concentrations in biogas increased in the presence of different particle sizes of ZVI in the order of nZVI>800m-ZVI>200m-ZVI.It increased by 15.5% and 40.6% in the presence of 0.1% 200 m-ZVI and nZVI respectively.The methane volume of production decreased by 12.5% in the presence of 0.1% 800m-ZVI during the 23 days anaerobic digestion.nZVI can reduce H2S release in sewage sludge effectively,and has the ability to boost methane production during anaerobic digestion dramatically.