污泥在超临界水中制取富氢气体的影响因素

Influence of Main Parameters on Hydrogen Rich Gas Production from Sludge in Supercritical Water

在反应温度为773-923 K、压力为22.8-37 MPa、停留时间为1-36 min以及水料比为2.6-6的途径下,使用超临界水（SCW）间歇反应器,对城市污泥在超临界水条件下制取富氢气体以及其中重金属元素的变化进行了实验研究。结果表明,反应温度和水料比对污泥转化的气相产物产率及组成影响较大。当温度由773 K提高到923 K时,气相产物产率增大了近1倍,其中氢气产率由16.54 mL/g上升到62.4 mL/g,升高了近4倍,H2和CH4的体积分率可达53.8%。当水料比由2.6提高到6.0时,气相产物产率及氢气产率均随之增大,氢气产率提高了1倍多,H2和CH4的体积分率达51.3%。与温度和水料比相比,压力和停留时间对污泥转化制氢的影响相对较小。

In this paper, hydrogen rich gas production from sludge and heavy metal elements transition in supereritical water is researched using a batch reactor. A series of factors are investigated, such as temperature （773--923 K）, pressure （22.8-- 37 MPa）, reaction time （1- 36min） and water/sludge weight ratio on gas composition and yield. The experimental results indicate that the key factors that affect the sludge gasification are temperature and water/sludge weight ratio. The gas yield increases about one time, the hydrogen yield increases from 16.54 mL/g to 62.4 mL/g about 4 times, and the volume fraction of H2 and CH4 reaches about 53.8% when the temperature changes from 773 K to 923 K. The gas products and hydrogen yield all increase, and the hydrogen yield increases more than one time with water/sludge weight ratio increasing from 2.6 to 6.0. Compared with temperature and water/sludge weight ratio, the influence of both pressure and residence time on sludge converting for hydrogen rich gas is less significant.