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โครงการหนังสืออิเล็กทรอนิกส์ด้านการเกษตร เฉลิมพระเกียรติพระบาทสมเด็จพระเจ้าอยู่หัว

the blue water requirements by around 38 and 192 litre of blue water/litre ethanol, respectively. In
addition, sugarcane is found as the crucial feedstock that can increase the security of feedstocks

supply for bioethanol production in Thailand and its performance in GHG emissions is better than
cassava and molasses ethanol. Nevertheless, based on the registered ethanol plants, there is only

one ethanol plant using sugarcane juice as feedstock in operation in Thailand (0.2 M.liter per day
ethanol production capacity). The government should therefore emphasize promotion of sugarcane

juice ethanol production by solving some of the existing constraints such as the Sugar Act of 1984
which does not support ethanol production from sugarcane, and the duration of sugarcane supply

which is limited to just over the period of December to March.

8.5.3 Enhancing water use efficiency in feedstock processing and ethanol conversion

Although feedstock processing and ethanol conversion have very low contributions to the

WF of bioethanol as compared to the crop evapotranspiration, those industrial processes directly
involve blue water use which is recognized as the important element of WF as it is more

associated with the environmental impacts as compared to the green water. To reduce the WF
during industrial stages, the water reuse and recycling program has to be encouraged. For

example, the condensate recovery in sugar mills and in ethanol conversion plant e.g. distillation
stage can help not only saving the water use but also help saving energy. Brazil has accelerated

the basic guidelines of water management to sugar milling industries along with the new
technologies development such as dry cleaning of sugarcane to eliminate sugarcane washing,

treatment of vinasse by biodigestion technique to reduce the organic load and recirculating into the
process (Macedo, 2005; Macedo et al., 2008). Moreover, the appropriate treatment and utilization

of the high organic wastewater generated from the mills and from the ethanol conversion such as
using it as agri-fertilizer can help mitigate impacts on ecosystem due to wastewater release.

Therefore, research and development for the feedstock processing technologies and ethanol
conversion technologies need to be encouraged.

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