An Update On the Bio-Energy Conversion Processes Utilizing Cotton Gin Trash

Various conversion processes of cotton gin trash into bio-fuels and bio-products are continually being investigated at Texas A&M University (TAMU). The current available technologies for conversion include the following: a mobile fluidized bed gasifier (FBG) for heat and power purposes and a mobile fast pyrolysis system for bio-oil and bio-char conversion. There are also other new processes being investigated to produce transport fuels using bio-chemical and thermo-chemical means. Each of the conversion processes will be discussed in this paper including their level of maturity and commercialization potential. For example, gasification of cotton gin trash has already been technically demonstrated in previous years. The main issue would be on the utilization of the products and by-products of the processes and the identification of further commercial economical applications. Drying wet cotton bales is the easiest and most practical application and would not require any further research. Electrical power production is also feasible if an appropriate scheme for the sale of electricity is identified, particularly taking advantage of the peak power demand in some areas. Bio-oil production via fast pyrolysis is gaining popularity for the production of refinery grade crude oil. High energy density bio-crude oil can be produced from cotton gin trash but the chemical composition is very different from refinery grade crude oil. The product is highly oxygenated, with some moisture and with low pH. The bio-oil has very high energy content of approximately 11,000 Btu/lb and may be mixed with fuel oil #2 or heating oil that may be used in boilers for heating purposes. Production of liquid transport fuel such as gasoline, diesel, ethanol and JP-8 may be realized in the future via other novel liquefaction processes. Many of these future research directions will be discussed in this paper.