Tohoku quake debris providing short-term boost
KAKOGAWA, Hyogo Pref. — It’s an article of faith among Japan’s fossil fuel advocates that because the country has no natural resources, it must import more than 80 percent of its energy needs.
|Chemistry 101: These bottles contain biomass fuel, the final product of a process that begins with pine trees. HARIMA CHEMICALS INC.|
But if the definition of natural resources is expanded to include waste products that can be turned into biomass energy, Japan has more resources for electricity generation than is often recognized. From wood products to sewage sludge, biomass energy advocates say, the domestic potential for electricity generation from biomass products can be greatly expanded with proper government support.
The Agriculture, Forestry, and Fisheries Ministry lists 13 different biomass sources in three categories: waste materials, untapped resources and crops for industrial use.
Waste materials include waste paper, animal excreta, food waste, leftover building materials, residue from lumber mills, liquid waste from pulp mills and sewage sludge. Untapped resources include biomass energy derived from rice straw, wheat straw and rice husks, while industrial crop biomass means energy derived from feed crops.
Japan’s total biomass production for electricity, heat utilization and biofuels reached 322 million tons in fiscal 2008, which translates into the equivalent of about 5.11 million kiloliters of crude oil. The recycling rate for biomass is 76 percent and the amount of unused biomass is estimated to be at 76.44 million tons annually, according to the agriculture ministry.
The abundance of waste resources is especially true in the Tohoku region, where dealing with the millions of tons of garbage resulting from the March 11 quake and tsunami is creating new opportunities for biomass power.
Over the summer, the Forestry Agency said it would look into building as many as five new wood-burning plants in Tohoku that would use timber waste left by the March 11 quake and tsunami.
|Harima Chemical Inc.’s biomass power plant in Kakogawa, Hyogo Prefecture, uses oil from American pines.|
“Initially, wooden pieces of debris will be used for power generation. After it becomes financially viable, wood thinning from forests will be used,” Takashi Shinohara, senior vice minister for agriculture, forestry, and fisheries told reporters July 13.
The theory is that the new plants will solve three problems. They’ll help get rid of the quake debris, promote biomass energy and help reinvigorate the forestry industry. The Forestry Agency estimates that 25 million tons of debris from housing alone was created by the tsunami, the majority of it wood. However, only around 5 million tons is considered usable for biomass plants, as the remainder is soaked with seawater.
Turning wood products into biomass energy is already happening across Japan, and one of the more unique operations is under way at Harima Chemicals Inc.’s Kakogawa plant in Hyogo Prefecture.
Here, oil derived from imported pine trees is turned into biomass fuel. Biomass energy advocates admit that burning biomass for fuel faces public concerns over how it smells. But the pine oil burned at the Kakogawa plant gives off a slightly sweet odor that is quite pleasant. It is the only plant of its kind in Japan.
The plant produces 4,000 kw, or about 16 million kwh annually. The generated energy is used primarily for the factory and the remaining is sold to an outside supplier. Normally, the plant operates at 50 percent capacity. But this past summer it reached 60 percent to help make up the electricity shortage caused by offline nuclear power plants.
Harima Chemicals’ main business is products made from pine chemicals, so the establishment of a plant that burned pine fuel was a natural step. The Kakogawa plant was built in March 2005 at a cost of ¥1.4 billion, and the central government paid for a third of that.
Harima’s biomass fuel is made from slash and longleaf pine trees imported from the United States. They are turned into pulp and liquid waste. The liquid waste is separated and refined into what is known as tall oil, which is further refined into a number of products, including rosin and fatty acids, that are sold to manufacturers of everything from ink to perfume. It’s at this stage, after the rosin and fatty acids are separated from the final mixture, that the oil for the generator is extracted.
“The oil extracted for biomass energy actually amounts to less than 1 percent of one pine tree. Compared with electricity generated from fuel made from more common waste forms, it’s much more expensive,” Fumiaki Tsuchida, director of the Harima plant, said without elaborating on the cost.
The majority of Japan’s biomass electricity production is from industrial waste products, especially from lumber mills and municipal waste. Like Harima, many private firms and public entities are interested in turning wood products into biomass fuel. But generation from wood chip products is still quite small compared with other countries.
Miyuki Tomari of the Biomass Industrial Network notes that, domestically, Japan is heavily forested with trees that might be used for wooden biomass. But many forests are in remote areas, and building road systems to reach them would be expensive. There are also environmental concerns.
“There are many kinds of biomass and we need to see whether it is truly good for the environment or not. For instance, using trees can sometimes be bad for the environment because after cutting them down no new life grows in their place and the devastated area remains,” Tomari said. “Rather than building new, specialized biomass plants, one option is to burn biomass fuel in existing coal or oil-fired plants.”
Japan currently has 190 generators attached to municipal waste units, plus another 14 generators that burn both coal and biomass products derived from a variety of sources. In addition, there are another 70 or so independent plants.
“It’s said that fossil fuel plants are not strong enough to burn multifuel sources. But this is just Japanese politicians being too afraid of new technology,” Tomari said.
The Japan Times