Impact of Carbonate Hydroxylapatite (CHAP) Addition on Bio-Hydrogen Production from Microwave Pretreated Sludge

In order to promote the hydrolysis and disintegration of waste sludge, the most logical approach is pretreatments to disrupt the microbial cells of sludge. After microwave pretreatments, the heavy metal which were toxicity to H2 production were released from waste sludge, and the increase rate was 10.6 (Cu), 5.5(Cd), 3.6(Zn) and 1.6 (Ni) times after pretreatment. Carbonate hydroxylapatite (CHAP) had high efficiency in heavy metal removal. In this study, the effect of heavy metal removal on bio-hydrogen production from microwave pretreated sludge using CHAP was evaluated. 0.53 g/gVSS CHAP addition could enhance the bio-hydrogen yield by 53.6% compared with control, and the lag time was 9 h. Dosages of CHAP couldinfluence the hydrolysis, fermentation type and hydrogen yield of pretreated sludge.