Janusz A. Kozinski
York University, Canada
Title: Gasification of lactose in supercritical water as a model compound of dairy industry effluent
Biography
Biography: Janusz A. Kozinski
Abstract
The adverse effects of climate change resulting from increasing greenhouse gas emissions and intense consumption of fossil fuels are well-known. The pollution of natural resources, such as water, air and soil, by refractory industrial wastes has also become a global environmental concern. The effluents from dairy industries are one of such wastes that require proper attention prior to disposal. Dairy effluents are comprised chiefly of spoiled milk, yogurt, cream, cheese whey, fat and other milk-based products. The dairy industry effluents, including whey waste and milk-based residues, are enriched in lactose and minor amounts of glucose that could potentially be converted to biofuels and biochemicals. Lactose was used in this work as a model compound of dairy effluents for gasification in supercritical water using a continuous flow tubular reactor. Four parameters impacting supercritical water gasification were studied, namely temperature (550-700°C), residence time (30-75 s), feed concentration (4-10 wt%) and catalyst concentration (0.2-0.8 wt%). The best total gas yields, carbon gasification efficiency, H2 yields and other major gases (CO2 and CH4) were obtained at 700°C using a feed concentration of 4 wt% lactose and a residence time of 60 s at 25 MPa. Furthermore, catalytic lactose gasification involving 0.8 wt% Na2CO3 resulted in maximum H2 yield (22.4 mol/mol) compared to those obtained by 0.8 wt% K2CO3 (21.5 mol/mol) and non- catalytic gasification (16 mol/mol). The results indicate that waste effluents from dairy industries could potentially serve as an attractive raw material for hydrogen production from gasification.