Air and air-steam gasification of sewage sludge. The influence of dolomite and throughput in tar production and composition

Integrated carbon dioxide/sludge gasification using waste heat from hot slags: Syngas production and sulfur dioxide fixation

“…A quartz boat was used to hold the samples and placed into a quartz tube reactor, which was externally heated by an electric furnace. Pure CO 2 was used to perform the gasification and the flow rate was accurately controlled by a mass flow meter, i.e., 200 ml/min; the gasification temperature was selected as 500-950°C, which was widely employed for sludge gasification (De Andres et al, 2011a;Nipattummakul et al, 2010;Roche et al, 2014). The tube reactor was first heated with the gasifying agent pumped into the system to fully expel the air inside and as the temperature reached the prescribed point, the quartz boat filled with samples was then placed on the right side of the tube for 20 min to stabilize the temperature and the atmosphere.…”

“…De Andres et al (2011a) investigated the air-steam gasification of sludge at 750-850°C using dolomite, olivine and alumina as catalysts and a syngas composed of CO, H 2 , CH 4 and CO 2 was obtained. Roche et al (2014) studied the air and air-steam sludge gasification and they found that dolomite enhanced the tar decomposition and increased the syngas yield at 800°C. Nipattummakul et al (2010) explored the evolutionary behavior of sludge-steam gasification at 700-1000°C and discovered that sludge yielded more hydrogen than paper and food wastes.…”

H 2 -rich syngas production through mixed residual biomass and HDPE waste via integrated catalytic gasification and tar cracking plus bio-char upgrading

“…The resulting C * species subsequently reacted with oxygen from dissociation adsorbed steam to yield CO and H 2 [51][52][53][54][55][56]. CaO and MgO which these oxides further enhance the tar cracking [20,[61][62][63][64][65][66][67]. Table 5 shows the effect of the dolomite bed on gas composition and tar cracking.…”

Investigation of the Structure of the Biochar Obtained by Slow Pyrolysis of Elephant Grass during Its Steam Gasification

“…Compared to other gasification agents, steam produces a gas with a heating value ranging from 10 to 18 MJ m −3 , whereas in air gasification processes the heating value of the gas is 4–6 MJ m −3 . Air‐steam gasification has also been investigated, as it makes the process cheaper . Steam gasification of the biochar produces a syngas through the primary reaction (i.e., C + H 2 O → CO + H 2 ) and the secondary water‐gas shift reaction (i.e., CO + H 2 O → CO 2 +H 2 ), which can be used as a gaseous fuel for direct power generation and/or hydrogen production or applied as a chemical feedstock for the synthesis of valuable chemicals .…”