8.5.1 What is a good source for ethanol production?

In Thailand, most existing commercial ethanol production plants use molasses as a feedstock but with increasing new facilities to use cassava in the near future. However, these two energy crops are still considered as food, which may interfere with the ‘food vs. fuel’ issue. As a result, more people are looking for alternative non-edible energy crops. Among many others, lignocellulose from various agricultural residues has received a great deal of attention, commencing the era of 2nd generation lignocellulosic bioethanol.

8.5.2 Lignocellulosic biomass feedstock for ethanol in Thailand

Each year in Thailand, agricultural industries generate millions of tons of various lignocellulosic biomass feedstock known as agricultural residues, including rice straw, sugar
cane bagasse, corn stover/fiber and wood chip. Sugarcane and rice, mostly concentrated in the North and Northeastern provinces, are the first two largest national agricultural productions (in weight) as shown in the table below.

Table 8.5.1. The first four largest agricultural production in Thailand (2004).

In general, these residues are inefficiently utilized, which most often, also causes environmental problems. Rice straw is considered wastes and disposed off through various methods such as open-air burning (as shown in Fig. 8.5.1 and 8.5.2), dumping or animal feeding. A rather more attractive method to mange these abundantly available rice straws is through cellulosic ethanol