Lezioni Zen – Il riciclaggio degli scarti alimentari in Giappone (eng.)
Immagine : Lenntech
In un post precedente avevamo parlato della necessità di separare i rifiuti. Per la gestione dei rifiuti è assolutamente necessario separare l’umido e poi tra vetro/plastica/metalli ed il cartaceo. Ecco lo stato dell’arte sullo smaltimento dei rifiuti alimentari.
Food Waste Recycling in Japan by Yuriko Yoneda
Daily meals are source of our energy. Dining together is essential for us not only from a nutritional perspective but also as a good occasion to communicate with families and friends. At the same time, we should note that a certain amount of food waste is always created whenever we have a meal. This article outlines the current situation of food waste recycling in Japan.
Waste Disposal System and Food Waste in Japan
The source of food waste can be divided into three stages from food producers to consumers: a production stage (including the processes at food processing companies), a distribution stage (including supermarkets and retailers where food waste including unsold products is generated), and a consumption stage (including restaurants and households, etc.).
In Japan, waste is mainly categorized as industrial and non-industrial waste. Industrial waste emitters are responsible to dispose of their waste, either on their own, or by contracting the work to waste management companies. On the other hand, when it comes to non-industrial waste, local governments are responsible for the disposal of waste generated in their municipalities.
Examples of waste at the food production stage include a variety of food processing residues, such as rice bran, bean curd refuse, and other ingredients’ residues, all of which are counted as industrial waste. Examples of waste at the distribution and consumption stages include unsold and discarded food products as well as leftovers, and these are treated as non-industrial waste.
In Japan, roughly 19.40 million tons of food waste were generated in 1996. Of these, about nine percent, or 1.68 million tons, were recycled. Some 50,000 tons of food waste from households were recycled, which accounts for only 0.3 percent of the total. Most of this garbage was incinerated and landfilled, contributing to Japan’s growing shortages of final disposal sites. Aware of this situation, the Japanese government enacted the Food Recycling Law in 2001, aiming to reduce food waste and promote recycling.
The law on food recycling requires all entities concerned in food waste at the stages of food production, distribution and consumption, including consumers, businesses, and the national and local governments, to endeavor to control waste generation, promote recycling, and reduce waste volume. Furthermore, the law requires all food-related businesses to increase their food waste recycling rates by 20 percent by fiscal 2006.
As a result, the food waste recycling rate increased to 20 percent in 2005 from less than 10 percent in 2002. Moreover, food-related businesses that are obligated by the law to take action boosted their recycling rate to over 50 percent in 2004. On the other hand, the recycling rate of household food waste has not risen. This is partly because very few local governments collect household food waste separately from other waste, although it would be an essential step to promote the recycling of this waste.
So how can food waste be recycled? The Food Recycling Law suggests four ways to recycle: composting, producing fodder for livestock, manufacturing oil and fat products such as bio-diesel and printing inks, and utilizing methane from fermentation.
Currently, most food waste is composted. Some food companies have been recycling organic waste into fodder for years by supplying food residue such as soybean meals, bread, and steamed rice to fodder makers to livestock feed.
Organic waste can be utilized as fuel raw material for bio-diesel and methane. Such initiatives are only a small portion of recycling, but they have already started in Japan. Below, we introduce some examples.
Recycling Organic Waste in Manure in Aya Town
In Aya Town of Miyazaki Prefecture, southern Japan, organic waste is a separate category from burnable garbage. Organic waste collected from each household is turned into composting and sold to local farmers as “Aya’s Natural Fertilizer” at a low price. Vegetables grown with the compost are sold to local consumers at the “Hon-mono” (real stuff) Center built by the town in 1988. This model demonstrates the circulation of nutrients within the community.
The town’s initiative to create a small-scale local nutrient circulation system is stimulating the community. Organic waste is collected separately from other waste, with the support of local residents.
Biomass Energy
In Kyoto City where the 3rd Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (COP 3) was held, an initiative to use organic waste as biofuel is now being developed. The city collects waste vegetable cooking oil from household and business sites such as restaurants, recycles into methyl ether (a bio-diesel fuel), and uses it to fuel the city’s garbage trucks and buses.
The city started collecting waste cooking oil from households in 1997, and gradually expanded the scale of operations. As of April 2006, it collects 130,000 liters annually at 956 collecting posts in the city. Combined with about 1.5 million liters of waste cooking oil collected at restaurants and cafeterias, the city processes the collected waste as a raw material for bio-diesel.
As Kyoto City considers setting quality standards of fuel–an important step to promote and expand the use of bio-diesel–it drew up the “Kyoto Standards,” the city’s tentative standards, by studying standards of the European Union, which is a frontrunner in the use of bio-diesel.
Kyoto has been operating a waste oil recycling facility that recycles 5,000 liters of cooking oil every day since 2004, to ensure the stable supply of quality fuel that meets the tentative standards. The recycling facility is the largest among those managed by municipalities across Japan. Kyoto pioneered in setting its own quality standards, well before the national government. The Japanese government is currently working on national standards, aiming at finalizing them by the end of fiscal 2006.
Kyoto also started a new initiative for biomass utilization. It is a technical demonstration project for a biogasification process, which generates biogas (mostly methane) from food waste, and then converts it into hydrogen for power generation using fuel cells. This is the first attempt in Japan in terms of using household food waste (which tends to contain non-food materials), instead of using sorted business food waste, and to recycle waste glycerin, which is generally treated as waste in biodiesel production.
Currently, hydrogen used for fuel cells is typically produced from fossil fuels such as petroleum and natural gas, but Kyoto uses food waste. The use of biomass, including food waste, does not lead to the problems related to resource depletion and accelerating global warming due to CO2 emissions. Kyoto’s initiative not only promotes the use of food waste, but it also contributes to cleaner automobile exhaust gases and reduces CO2 emissions, making it an outstanding effort to try something new.
National Strategy of Biomass Utilization
The Japanese government is now working on a “Biomass Nippon Strategy,” which promotes the nationwide use of organic resource of biologic origin. This means biomass, including food waste. By providing information through brochures and a website as well as subsides for biomass related studies and projects, the government is trying to make Japan a society that makes the maximum use of biomass, by around 2030.
Food waste may be a problem if it is simply disposed as garbage, but it becomes a resource if used again. We hope to see more efforts using food waste as resource, as Aya Town did by using the wisdom and cooperation available within the community, and as Kyoto City did by using advanced technology.
Meanwhile, Japan’s food self-sufficiency rate is only 40 percent on a caloric basis. Japan imports a substantial amount of food from abroad and generates plenty of food waste as leftovers. It is important to recycle food waste as a resource, but we also need to take action to reduce the absolute amount of food waste.
