1. Pyrolysis of Bioenergy Crops Grown on Reclaimed Mining Land in
West Virginia
Oluwatosin Oginni and Kaushlendra Singh
School of Natural Resources, West Virginia University, Morgantown WV 26506
INTRODUCTION
RESULTS
RESULTS
Pyrolysis is the thermal decomposition of biomass in a temperature range of about C in the absence of oxygen to produce bio-oil, bio-char and incondensable gas.
Bio-oil is a dark-brown, free flowing liquid with a distinctive smoky smell and with intense effort on upgrading its physicochemical properties, it has been identified as a promising substitute for conventional liquid fuel.
Biochar possesses remarkable properties leading to its high reactivity and hence becoming an attractive by-products with applications including combustion, gasification, soil amendment, production of activated carbons, which is useful as a sorbent for air pollution control as well as for wastewater treatment.
The objective of this work compare pyrolysis characteristics of two energy crops (miscanthus and switchgrass) and their two cultivars grown on reclaimed mine land in West Virginia.
Bio-char
Fig 9: Carbon, Hydrogen, Nitrogen and Sulfur content of Biochar
Fig 3: Percent Yield of Bio-oil, Biochar and Biogas
Fig 4: Energy Content of Biomass, Bio-oil and Biochar
Dedicated Energy Crop
Pyrolysis
METHODOLOGY
Biomass samples (Switchgrass Kanlow, Switchgrass Bowmaster, Miscanthus Private and Miscanthus Public) were chopped into small sizes and oven dried at 103 0C for 24 hours.
Pyrolysis of the biomass samples were carried in a batch pyrolysis reactor at temperature of 500 0C for 30 minutes (Fig 1) under constant flow of nitrogen.
Ultimate and proximate analyses of the bio-oil and bio-char samples were carried out using a CHNS/O and proximate analyzers (Fig 2a &b).
Yields of pyrolysis products and distribution of biomass carbon and energy into the pyrolysis products were calculated.
Fig 10: Carbon, Hydrogen, Nitrogen and Sulfur content of Bio-oil
DISCUSSION
Bio-oil yield for miscanthus private was the highest which implies that it is a good potential for large scale production of bio-oil.
The high energy content of the bio-oil implies that it can be used as a substitute for conventional liquid fuel when subjected to upgrading.
The carbon yield and energy conversion efficiency of the bio-oil were higher than that of the bichar. This is an indication that a higher percentage of the carbon present in the biomass were converted to bio-oil.
Volatile content shows the amount of combustible material in sample. It is inversely proportional to the ash content, which is a representation of the mineral content of a material.
Biochar contains higher content of carbon as compared to bio-oil, hence enhancing its reactivity and making it a good potential for activated carbon
EXPERIMENTAL SETUP
Fig 5: Carbon Yield and Energy Conversion Efficiency
of Biochar
Fig 6: Carbon Yield and Energy Conversion Efficiency
of Bio-oil
Fig 1: Photograph and schematic diagram of the batch pyrolysis system
CONCLUSION
Switchgrass and Miscanthus varieties obtained from the reclaimed mine land are good potentials for large scale production of bio-oil
The carbon yield of the biochar which is above average and its low ash content will enhance its use for production of activated carbon.
Further works include pretreatment of the biomass prior to pyrolysis and chemical activation of the biochar for activated carbon production
Fig 7: Volatile Content of Biomass and Biochar
Fig 8: Ash Content of Biomass and Biochar
ACKNOWLEDGEMENT
Farm Credit of the Virginias
School of Natural Resources, West Virginia University, Morgantown WV
Fig 2a: CHNS/O Analyzer
Fig 2b: Proximate Analyzer