Effects of Temperature and pH on Denitrification Process on Woodchips with Low Lignin Content
As a widely studied carbon source material,the outstanding problems of woody biomass are slow denitrification rate and more by-products.Therefore,the denitrification process was subdivided into carbon release and denitrification stages by using alkali treated wood with low lignin content as raw materials.Experiments were designed to determine the concentra-tion of"trinitrogen",total nitrogen and dissolved organic matter(DOC),and the spectral characteristics of DOC.The results showed that the sensitivity of carbon release and denitrification to temperature change was different,while the rates of carbon release and denitrification were 2.6 and 1.1 mg/(g·d)at 15 ℃,respectively,which increased to 1.7 times and 1.5 times at 25 ℃,and 1.7 times and 2.1 times at 35 ℃.Carbon release was inhibited at pH 5.0 and 9.0,while denitrification was obviously weakened at pH 9.0.The peak value of nitrite nitrogen was the highest at 15 ℃,accounting for 35.7％of nitrate nitrogen removal,and the maximum ratio was at pH 9.0.During denitrification,the residual DOC accounts for 44.6％～52.0％of the total carbon released,including proteinoid and humic acidoid.
万方数据
维普
