Low-temperature alkaline pyrolysis of sewage sludge for enhanced H_2 production with in-situ carbon capture

摘要

Pyrolysis has been recognized as one of the promising thermal technologies on the account of satisfying the principles of waste reduction, resource recovery, and detoxification. This study proposed the alkaline thermal treatment of sewage sludge of enhanced H-2 production and in-situ carbon capture. The maximum H-2 yield of similar to 10 mmol g(-1) biomass was achieved at 1:3 sludge: NaOH ratio, 10 degrees C min(-1) heating rate, and 500 degrees C temperature, with the H-2 purity of 79.1% in the gaseous products. The presence of NaOH significantly promoted H-2 production and substantially suppressed CO and CO2 . Temperature also played an important role in cracking of C-C and C-H bonds and gave H-2 -rich gas (H-2 formation rate 0.34 mmol min(-1) g(-1) ) with a high yield of 10.3 mmol g(-1) at 500 degrees C. The solid residue analysis via XRD verified the existence of Na2CO3 in the solid, implying the inherent carbon management potential of the NaOH during the sludge pyrolysis process. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.