Hydrogen production from biogas using hot slag

Development of Heat Exchanger with New Mechanism of Scraping Temperature Boundary Layer

“…Recovery of the waste heat is one of these approaches, and its concept is the effective use of unused energy in the industry. [1][2][3][4][5] The industry releases waste heat as various forms such as heat loss from furnaces, sensible heat of exhaust gases, radiation from high temperature materials, and so on. For each form of waste heat, suitable recovering methods were proposed.…”

Multi-Stage Control of Waste Heat Recovery from High Temperature Slags Based on Time Temperature Transformation Curves

“…This stage was suitable for combination of waste heat recovery from high temperature slags with other new heat utilization methods, such as H 2 production, coal gasification and heat storage in PCM because the slags have been totally solidified. Purwanto et al [23] have studied the hydrogen production using biogas and hot slags and the temperature range in their study was from 973 K to 1273 K, which was located in the temperature zone of solidified slags. They found that the slag acted not only as a good thermal media but also as a good catalyst for H 2 production.…”

“…To solve the aforementioned problems and realize the recovery of waste heat, a dry granulation method has been proposed, through which the liquid slags are granulated into small droplets with the diameter of several millimeters using different waterless granulation technologies, such as rotary cup atomizer [15][16][17][18], rotating drum [19,20], air blasts [21,22] and so on. Recently the combination of dry granulation with other waste heat utilization methods, such as hydrogen production from biogas [18,23], coal gasification [24,25] and heat storage of phase change materials (PCM) [26] has been intensively studied, and is expected to be a promising method in the future. Whatever the utilization method applied, the understanding of the variation of slag properties during cooling processes and the control of heat transfer are fundamental for simultaneously realizing waste heat recovery and slag recycling.…”

Synthesis of hydrogen-carbon monoxide fuel from methane-carbon dioxide mixed gases

“…As a product, formation of H2 was recognized. The high stability of CH4 at a high temperature results from the strong sp 3 hybrid orbital. Reduction of pyrolysis temperature is needed to use as a fuel of low temperature SOFC operated at 500−800°C.…”

“…(2) This carbon deposition caused the blockage of gas flow in several hours. In the lower temperature below 600°C, the formed CO decomposed to CO2 and C. (3) This is another process of carbon deposition. Although CH4 reforming with CO2 is an attractive reaction, the above parallel reactions of carbon deposition should be prevented to maintain the smooth gas flow during the reforming of CH4 with CO2.…”