Status Of Organics Recycling/Composting In Japan

From BioCycle
Journal of Composting &Organics Recycling
June 2001, Page 61

Focus On Japan
STATUS OF ORGANICS RECYCLING/COMPOSTING IN JAPAN
How many tons of compostable MSW, food industry residuals, animal manure, biosolids and woody materials are generated each year? How much is composted and recycled? A special JORA committee supplies the answers.
Mitsuo Chino

MEMBERS of the Japan Organics Recycling Association (JORA) based in Tokyo organized a committee to estimate the amount of “organic waste material of biological origin” generated annually in Japan — and the percentage being composted and recycled. These organic residuals include animal manure, biosolids, food industry residuals, municipal garbage and woody materials. Since official information on national generation and reuse statistics was not available, the committee utilized latest data in many different categories. Our data indicated that 280 million tons (fresh weight basis) of organic residuals are generated in a year, which represents 60 percent of the total solid waste produced.

Estimated total nitrogen, phosphorus, and potassium (N, P, K) in these residuals are equal to or greater than the total fertilizer equivalents used in Japan to grow crops. The nitrogen equivalents in the organic residuals listed represent 2.6 times of fertilizer N applied; phosphorus quantities were equivalent; and fertilizer potash represent 1.9 times of the amount used.

Status Of Disposal And Recycling For Organic Residuals

Straws And Husks Of Cereals
As shown in Table 1, the total amount of cereal straws (rice, wheat, and barley) and rice grain husks is 14 million tons. (Rice straw is approximately 11 million tons.) In the past, straw and husks were burned in the field and caused air pollution problems, but now 95 percent of rice straw, 72 percent of wheat and barley straw, 73 percent of rice grain husks are effectively used for compost, fodder, straw mats and other applications.

Animal Wastes
Annual production of animal excretion is estimated to be 94 million tons, 65 million tons as feces and 29 million tons as urine. It is reported that 94 percent of the total animal excretion is recycled to farmland and grassland after drying or composting. However, the increase of concentrated livestock production makes it difficult to recycle their waste because the area of land near the animal waste production sites is limited. This sometimes causes pollution of the rivers, lakes, groundwater and ocean. Food waste from meat processing such as bone or fat has increased to 1.67 million tons, following an increase in meat consumption. Most of this material is utilized effectively as cooking oil, fodder, and some industrial materials. It is also often used as the material for organic fertilizers.

Wood Residuals
The annual production of wood residuals such as bark, sawdust and wood chips is about 5.34 million tons (13,357 million cubic meters) (Table 2). About 95 percent of these residuals are utilized effectively. About 40 percent of the waste is used for pulp production and the remainder for fuel, mats for livestock, bedding and other purposes. The landfilled or the incinerated portion is about five percent. The material from pruning trees or trimming grass has grown and now represents six percent of total wastes, or 2.47 million tons, due to the recent increase of parks, roadside trees, and gardens in Japan.

Food Residuals
The difference between the domestic food consumption calculated on the supply basis (the Ministry of Agriculture, Forestry and Fisheries) and the food intake calculated on the nutrition demand basis (the Ministry of Health and Welfare) gives an estimate of the annual production of food residuals. This category is estimated to be 18 million tons. On the other hand, it is estimated to be 20 million tons based on the ratio (40 percent) of food residuals to the total domestic wastes. Most food residuals are handled as domestic waste and disposed of by incineration and landfill, while only 0.1 percent is used for composting. Recently, local governments began seeking ways to reduce wastes and/or another way of disposal rather than incineration, due to the generation of dioxin by incineration.

Annual production of food residuals from the wholesale markets is estimated at 2.8 million tons. Annual production from retail stores is 4.81 million tons. Most of it is disposed as domestic waste. Major convenience store chains have begun trying to compost their food residuals.

Wastewater Solids From Food Industry
The annual production of sludge (wastewater solids) from food industries through the food processing is about 15 million tons; residue of animals or plants is about 2.48 million tons. About 89 percent of total production is reduced by desiccation, 3.7 percent of the waste is recycled, and seven percent is disposed by incineration and landfilling.

Biosolids
The annual production of biosolids has increased to 85 million tons (as concentrated sludge) or 1.71 million tons (as dry sludge) from municipal wastewater. Thirty percent of the biosolids are effectively reused, 40 percent as compost and 60 percent as the material for cement. About 200,000 tons of biosolids are used as an ingredient for organic fertilizers prepared by fertilizer companies.

Present Status Of Compost Production

The number of compost producers and the amount of compost produced are increasing as shown in Table 3. As of 1996, the number of the compost producers and suppliers of special fertilizers was 5,772; the number of importers of such fertilizers was 457. Annual production of compost was three million tons. The production of bark compost and cattle manure compost especially has greatly increased recently.

The prices of composts are not constant and not determined by cost-profit balance of the producers. The products that have been accepted in the market as efficient organic fertilizers, with high nutrient value, are sold at relatively high prices. While the products such as animal waste, rice chaff, or sawdust are sold at reasonable prices according to farmers’ evaluations (5,000 to 10,000 yen/ton), although the costs of producing this kind of compost is about the same as the costs of producing high priced products. (10,000 yen = $82.20 U.S.)

In Japan, incineration and landfilling are widely used for disposal of organic residuals. However, there is a concern that these methods may cause various problems — namely a generation of toxic substances like dioxin, shortage of places for landfill, accompanied with a rise of disposal cost, and interruption of recycling within the agriculture, forestry and fisheries ecosystem. Recycling would promote the use of organic resources, reduce negative impacts to the environment, and improve agricultural production.

It is necessary to survey the balance between the supply and demand of the compost products correctly, locally and nationally in order to effectively recycle the huge amount of organic residuals generated. If all the organic residuals are recycled by composting, it will change agriculture drastically, i.e., more than 50 percent of fertilizer nutrient could be provided by the compost. If we apply the compost to all the farmland in Japan, five million hectares, at the rate of ten tons/hectare which is a reasonable rate for crop production, we would need 50 million tons of compost. This will cost 500 billion yen, assuming that the price of the compost is 10,000 yen/ton ($82.20 U.S.). Further, if we do this, up to one million tons of nitrogen will be recycled from the compost. However, we must realize that it is very difficult to accomplish this.

Mitsuo Chino is with the Akita Prefectural University, Faculty of Bioresources Sciences.

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