The first commitment period of the Kyoto Protocol towards carbon dioxide (CO2) reduction will come in several years. The movement towards effective use of biomass resources is becoming more and more intense. Furthermore, the attention to biomass as alternative energy source is increasing steadily due to the surging price of crude oil. Our company has been receiving the support from NEDO since 2001 on the development and production of ethanol as fuel source using waste house wood. In this paper, the movement towards the content and putting it into practice is introduced.
1.Technical development for ethanol production using waste house wood
Plants absorb CO2 in the air and fix carbon through the process of photosynthesis to release oxygen and water. They are reproducible resources ? cycling harvest and growth. From the viewpoint of CO2 reduction and establishment of the continuity of human society, as well as all living matter in the future, plants and their products are highly valued among the biomass resources.
In the current development of ethanol production, plant products composed mainly of starch and glucose are used. Specifically, they are crops such as corn, wheat, and cassava, which are made of starch, and sugarcane, which contains glucose. However, there is a possibility of fluctuations in prices in the market because they are in demand as food. On the other hand, woody materials are now treated as waste. Among these unused resources, construction waste house wood is being collected in Japan.
We developed the technology for making this waste house wood as materials for production of ethanol as fuel source. The flow of the process is shown in Fig.. We used a dilute sulfuric acid method. Woody materials are decomposed into acid with dilute sulfuric acid as a catalyst. Molasses obtained after neutralization was fermented into ethanol by a transgenic bacillus.
Fig. Process flow
2. The fuel-ethanol market in Japan.
The use of ethanol for automobile fuel started in Brazil 20 years ago. In the U.S., this trend has been spreading rapidly for the last five years. Ethanol 10% (referred to as E10) is mixed with gasoline and is utilized as fuel in the U.S. In Japan, E3 is being developed and promoted with the anticipation of its acceptance as fuel in the future. Nowadays in Japan 60 million KL of gasoline is consumed per year. If E3 is considered, ethanol market of 1,800,000 KL will be produced per year. The Ministry of Economy, Trade and Industry also aims to increase ethanol mixing of 300,000KL annually until 2008 and it has started concretely towards enforcement.
3. An effort for putting into practice
TAISEI CORPORATION, Daiei Inter nature, System, INC., Marubrni Techno-Systems Corp., SAPPORO BREWERIES LTD., and TOKYO BOARD INDUSTRIES, CO., LTD are now our stockholders. In Osaka, the construction of commercial facilities using this technology has just started. These facilities are expected to produce ethanol in 2007. A proper processing law is now imposed by the revised Construction Material Recycling Act.
Although the amount of waste house wood is increasing, it is gradually getting difficult to obtain them because construction of biomass power generation has been growingrecently. Under these circumstances, we plan to put into practice this project in metropolitan area or in other metropolitan spheres. The use of gasohol, on the other hand, is widespread in Southeast Asia. Especially in Thailand, the construction of facilities for ethanol fermentation, which uses waste molasses as material, has started. We, therefore, think that there is a big possibility of the fuel-ethanol production by applying our technology to bagasse, the strained lees of sugarcane. In addition, these are very user-friendly biomass resources because surely these are brought into a sugar factory. Regarding bagasse, we are planning to make a technical proposal to sugar companies in Southeast Asia using the same technology in the processing of waste-house-wood.