No abstract

a b s t r a c tAll around the world research is being conducted in the field of renewable energy due to the depletion of fossil fuels and the problem of global warming. Fast pyrolysis, an optimal technology for converting biomass to liquid fuel, enables lignocellulosic raw materials such as wood, switch grass and rice straw to be converted to biocrude-oil. Even though many studies on these materials have already been conducted, the high production costs and unstable supply thereof have frequently been pointed out as significant problems. Thus, this study considers the use of another feedstock to solve such disadvantages and to raise the recycling rate of organic wastes simultaneously. Swine manure was selected as an alternative feedstock due to the existence of a stable supply from the livestock farming industry. A bubblingfluidized-bed reactor was used in the present study for fast pyrolysis. The yield and characteristics of biocrude-oil were investigated at various reaction temperatures. The optimum temperature for maximum biocruce-oil yield was found to be 600 C with the highest yield of 18.48 wt% and HHV of 13.59 MJ/kg. Due to its low yield and high water content, swine manure is suggested to be blended with other types of biomass as a means of higher yield and quality of biocrude-oil.

Coffee grounds are considered to be a promising biomass resource due to the growth of coffee consumption and their high calorific value. In this study, we produced biocrude oil from coffee grounds in a tilted‐slide reactor, which has been previously used for the fast pyrolysis of woody biomass. Various pyrolysis temperatures were tested and the maximum biocrude oil yield was 59% at the pyrolysis temperature of 550°C with a feeding rate of coffee grounds at 17.7 kg/h. In a multistage condenser, the biocrude oil yields and properties were different in each condenser stage. The higher heating value of the biocrude oil from the primary condenser was 7,157 kcal/kg, which was about 60% higher than that from woody biomass. A phase separation was observed when the biocrude oil was stored at the atmospheric condition, and the biocrude oil viscosity became quite larger than that from woody biomass, which could even impede its flow. The viscosity decreased with increasing temperature and was more sensitive to temperature variations at lower temperatures. Mixing of ethanol also significantly improved viscosity characteristics. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 655–661, 2017

a b s t r a c tA burner system with capacity of 30,000 kcal/h was designed for the combustion of biocrude-oil and ethanol blends. An air atomizing spray nozzle with larger fuel orifice was adopted to prevent nozzle clogging, with swirl flow introduced to the combustion air for flame stabilization. Biocrude-oil was prepared from the fast pyrolysis of woody biomass and was blended with ethanol to improve flame stability and ignition characteristics. At various mixing ratios of biocrude-oil and ethanol, flame stability was determined, and gaseous emissions of CO and NO were measured. It was found that stable combustion could be achieved with up to 90 vol% of biocrude-oil. CO emissions of biocrude-oil/ethanol blends were smaller than those of pure ethanol, whereas CO concentration increased significantly in case of pure biocrude-oil due to incomplete combustion. Pollutant NO emission increased slightly with the biocrude-oil mixing ratio. The biocrude-oil burner in this study could provide a design database for industrial burner development.

a b s t r a c tA tilted-slide fast pyrolyzer was designed for the large-scale production of biocrude-oil. Woody biomass (Douglas fir) was fed into the reactor under different experimental conditions, including reaction temperature and biomass feeding rate, in order to study the biocrude-oil yield and its characteristics. One spray type condenser was used to condense the biocrude-oil by direct contact heat transfer and three shell and tube type condensers were used to collect biocrude-oil by indirect contact heat transfer. The highest biocrude-oil yield (61.9 wt.%) was obtained at 490 C and a feeding rate of 12.5 kg/h, with most biocrude-oil was collected in the spray type condenser. The characteristics of the biocrude-oils obtained from each condenser were scrutinized and compared, and GC/MS analysis was also conducted to ascertain the chemical components of the biocrude-oil thus obtained.