Proposal to Municipal Solid Waste Management of Nagoya City; Especially about Management of Bio-waste

Transcription

1 Proposal to Municipal Solid Waste Management of Nagoya City; Especially about Management of Bio-waste Tomoko Okayama 1 1. EcoTopia Science Institute, Nagoya University, Nagoya, Japan Abstract: Nagoya City fell into the municipal waste emergency in 1999, and has succeeded in the reduction of waste since then. At this time, strict segregation and recycling of all the container and wrappings were principal measure to reduce waste. Now, bio-waste, especially kitchen waste is paid to attention as a new segregated article in Nagoya city. In this study, with explaining the progress of the waste policy of Nagoya city, the processing situation of the kitchen waste of Nagoya City is analyzed, and it proposes the kitchen waste processing measures that Nagoya City should be going to take in the future. The participatory conference (Forum) held in Nagoya City in 2006; at the stakeholder conference and the citizens conference, the kitchen waste recycling became an important issue. As of July 2007, the agenda is being discussed by the kitchen waste examination team in more detail to contribute to consensus building as the 4th waste management plan of Nagoya City. The following data is offered to the second conference of the kitchen waste examination team. The current state of the kitchen waste of Nagoya City is estimated from the data of the Ministry of Agriculture, Forestry and Fisheries and Nagoya City Environment Bureau. About million tons of food was input into Nagoya City in 2004, after it was consumed, 257 thousand tons were discharged as the kitchen waste. 256 thousand tons were incinerated, and 24 thousand tons were finally land-filled. Then, 667 tons of segregated and collected kitchen waste was recycled into compost. From these results, if the target of reduction of the kitchen waste is set as 40%, discharge control should be the most important measure. Moreover, when discharge control in each home (squeezing water, using the disposer, and using personal composter, etc.), and a present sorted collection are combined, it is considered that 40% reduction in the amount of the kitchen waste disposal is possible. Keywords: kitchen Waste, Material Flow Analysis, Municipal Solid Waste Management 1. INTRODUCTION In Japan, the reduction of municipal and industrial waste has been one of the most important policies, because Japan has have difficulty of final waste disposal and constructing landfill sites seriously. In the 20th century, the volume reduction by incineration was the main processing method of municipal waste, however, Fundamental law for establishing a Sound Material-Cycle Society (at the following, the Material-Cycle Society law) was enacted in 2000, and the traditional waste disposal policy progressed to 3R policy. 3R means Reduce that control waste discharge, Reuse that is maintenance and repair to use goods many times or long time, and Recycle. Then, if waste goes out at the end when 3R was done, the waste is properly processed. This order; Reduce, Reuse, Recycle and properly process, is priority in the Material-Cycle Society law, and a Sound Material-Cycle Society is defined as the achievement of 3R. Up to now, some municipalities have indifferently incinerated and land-filled the municipal waste that the citizens have thrown away, however, they come to have to request cooperation to the citizens along with 3R policy introduction. The activities that citizens come to be requested are the followings; (1) Being green consumers who do not buy too much too many and select the goods that have less waste, (2) Doing reuse that use as long as possible or use second hand goods, (3) Doing strict segregation to sort recyclable material from their waste and discharge waste properly. These changes give more burdens to the citizens, comparing with traditional waste processing of Japan. Of course, the recycle of glass bottles and cans have already been done for these 30 years for example, therefore the collection rate of glass bottles and cans is extremely high now. Nonetheless, an enough result has not been achieved about reduction of total amount of municipal waste. The processing capacity did not catch up with the amount of waste that kept increasing in 90's, so the Containers and Packaging Recycling Law (at the following, the recycling law) was passed in 1995, and this simple recycling policy was changed into 3R policy based on the Material-Cycle Society law in Therefore, it is recent that the effect of 3R activities of the citizens has emerged in Japan [1]. This study takes a case study of Nagoya city because the city changed its waste disposal policy from only processing by incinerator to recycling for response a serious crisis of municipal solid waste management in The city needed to reduce its solid waste especially the amount of landfill, and it is one of the cities that have challenged to be 3R society and now the city has plenty experience of recycling. Now, Nagoya city is making the next plan of municipal solid waste management and especially the discussion about kitchen waste recycle is one of main topic of the plan. In this study, with explaining the progress of the Corresponding author: T. Okayama, tomo-okayama@esi.nagoya-u.ac.jp 638

2 waste policy of Nagoya city, the processing situation of the kitchen waste of Nagoya city is analyzed, and it proposes the kitchen waste processing measures that Nagoya city should be going to take in the near future. 2. THE EXPERIENCE OF WASTE MANAGEMENT OF NAGOYA CITY Nagoya city is located in the middle of Japan, and it is the capital city of Aichi prefecture. It has 2,223 thousand population in 2007 and this is the 4th largest population in Japan. Industrial shipment value was about 29,675 million dollar in In 1990 s, Nagoya city had serious problem about waste management, because its recycling policy could not reduce the amount of disposal waste, as a result, its shorted landfill site. It was estimated that its only one landfill site would be totally full in So, the city needed to construct immediately a new landfill site in a corner of the Nagoya port where the city bought already. However, the corner of Nagoya port is a tidal land, and it is a valuable feeding place for migrating birds. Therefore, some NGOs strongly opposed the construction of the landfill site in this corner. Though Nagoya City negotiated with Aichi Prefecture, the Ministry of the Environment, the Ministry of Transport and some NGOs, the City consequentially abandoned construction in January Then, The Nagoya mayor declared the municipal waste emergency in February Nagoya City faced emergent crisis of disposing of municipal waste. Responding to this situation, Nagoya city had to change its waste disposal policy. The city introduced recycling programs as many as possible. In particular, it carried out recycling all items of containers, packaging and wrapping on the recycling law as the main policy. As a result, it is observed that the recycling law has accelerated to segregate the containers and packaging from the waste, and it not only has reduced the amount of waste but also has changed the contents of waste into good for incinerating. The amount of landfill reduces 0.15 million tons, it becomes almost half after introducing recycling policy. Nagoya City assured the capacity of landfill space of ten years in October 2001, and escaped from the crisis. The total amount of municipal waste also decreased about 6 tons. If the citizens of Nagoya city became green consumer and controlled waste discharging, it could be said that Nagoya city became 3R society. However, there are no evidences of life style change in some consumption statistics. It clearly shows that the recycling based policy has succeeded in reducing the amount of waste to go to landfill sites, then it also reduced the environmental impacts because the amount of PET bottle and other plastic wrappings included in incinerated waste was reduced, the discharge of CO2 and NOx from incineration process reduced remarkably. Now, Nagoya city is going up to the next stage. During the crisis, the city had the second municipal waste-processing plan, and after the crisis, it made the third plan. Nagoya city is making a decision about 3R activities of the city, and some stakeholders and actors around waste management of the city have held the participatory conferences several times in 2006 and early 2007, still they are on going. Such a decision-making is an example case of partnership of citizens and all actors. 3. RECYCLE OF BIO-WASTE 3.1. Overview of participatory conference of the city Nagoya city noticed that it needs citizens participation and partnership of actors to become a 3R city. Therefore, the city tried to formulate the fourth municipal waste management plan with the citizens participatory conference. In August 2006, the conference committee was set up to drive the stakeholder conference and the citizens conference forward. The stakeholder conferences were held five times and the citizens conferences were held six times by turns since September 2006 till March 2007, and all the participants had an associated session on 15th April 2007 to have consensus about 3R proposal. The stakeholder conference agreed on a basic outline to make the scenarios for some experts of waste processing. Actually, they suggest two axis, X-axis means the participation and cooperation of stakeholders of Nagoya city, and Y-axis means the target of waste reduction. Seeing Figure1.[2], the experts made four scenarios according to the axis. Figure 1. 4 scenarios to make Nagoya city 3R society (Source: [2]) The citizens conference had the election to decide a scenario finally, and scenario A collected points the most. At the associated session in April 2007, all the participants certified the scenario that was made through participatory conferences. The basic outline of the scenario is below; 1) Waste including recyclable material reduction on all the process, producing, distributing and consuming, 2) more recycling, 3) minimization of the amount of land-filled waste, 4) fair responsibility on the discharger of waste 5) the cultivation of human resources, partnership, 6) to show clear division of roles of all actors Team to drill down on the recycle of bio-waste After finishing all the citizens conferences in April 2007, some staff and participants made three teams to have some discussions to drill down on issues related to the scenario, 3R and municipal waste management of Nagoya city. One of the teams is discussing about the recycle of kitchen waste. Nagoya city is collecting all kinds of Packaging and containers now to recycle, but kitchen 639

3 waste, bio-waste is just combustible garbage to go to incinerator. Related to basic outline of scenario 2), the team started discussion about reducing and ways of recycle of new item, kitchen waste Status analysis of bio-waste of Nagoya city The team has have meetings six times since 6th June till 29th August. In the first meeting, the members gathered their family data for understanding the status of discharge of kitchen waste. They also read the final report of the committee for kitchen waste recycling [3], and discussed about how to control discharge of kitchen waste and how to recycle it. The author was a leader of this team. So I participated all the team meetings, and I researched about the status of kitchen waste in Nagoya city with some data of Nagoya city and others. The following data and analysis were shown to the team member for discussion. Table1 shows the population and number of households of Nagoya city. Figure 3. Breakdown of kitchen waste Table 1. Population and number of households of Nagoya city Year Population (Person) Number of households 2,161,680 2,177,451 2,202, , , ,328 Figure 4.Kitchen waste flow of Nagoya city (1998) Figure 5. Kitchen waste flow of Nagoya city (2001) Figure 6. Kitchen waste flow of Nagoya city (2004) Figure 2. The contents of municipal households combustible waste of Nagoya city (2006) Total amount discharge of kitchen waste is estimated by the data of the Ministry of Agriculture, Forestry and Fisheries of Japan [4], population of Japan and Nagoya city. Figure 2 and Figure 3 are the researched data of combustible municipal waste composition of Nagoya city in The flow of kitchen waste of municipal solid waste is shown as Figure 4 in 1998, Figure 5 in 2001and Figure 6 in The flows of kitchen waste are considered. Three years status were analyzed, from 1998 when was before the municipal waste crisis of Nagoya city, 2001 when the result of waste reduction policy appeared, and in 2004 when is continuing to present. They were estimated by the data of Ministry of Agriculture, Forestry and Fisheries of Japan, population of Nagoya city, consumption statistics, and municipal waste composition analysis of each year. The kitchen waste that has been discharged as nonflammable garbage is kitchen waste that mixes with nonflammable waste. The total amount of kitchen wastes mixing within combustible waste, nonflammable waste and sorted collection for recycle is the amount of discharged kitchen waste in Nagoya city. Kitchen wastes in 640

4 the combustible waste is always occupied about 36% to 42%, and exists as untapped resources in the municipal waste, though the total amount of kitchen wastes tends to decrease according to Figure 4, Figure 5, and Figure 6 [5]. About 7,500 families of Minami ward in Nagoya city do the segregation of kitchen waste to recycle in This recycling rate is 0.26% in the entire Nagoya City. The method how the recycling rate is raised will be an important issue from now on. From this analysis result, it is understood that about 23% to 29% of the total amount of foods input to the market in Nagoya city has been discharged as unused or a leftover. According to the result of report by Health, Labor and Welfare Ministry, the National Health and Nutrition Examination Survey (2003), it is estimated that the food of 25.8% is thrown away without being consumed based on the calorie, hence the material flow analysis of kitchen waste in Nagoya city is considered to be not so far from actual status. From this analysis, it should be said that the control of discharge is more important than only recycle of kitchen waste, because more than 23.0% of foods are discharged as waste. However, the market of the food sales is not changed only by the policy of Nagoya city and the citizens activities. It is necessary and important to discuss among stakeholders and actors about method of processing kitchen waste, ways of recycle, cost, effect of the environment and qualitative problems [5] Quantitative estimate of kitchen waste reduction Table 2. The amount of kitchen refuses discharge per capita in Nagoya city Year kg/year g/day Figure 7. Kitchen waste flow: Breakdown flow of Figure 6. (2004) According Figure 2, kitchen waste is 44.0% of all combustible municipal waste. And Figure 3 shows that the ratio of vegetables and fungus after cooking is 54.0%, fruits after cooking like peeled skin of apple has 17.0% and other kitchen waste like coffee powder has 5.0% among total kitchen waste. It means that if all the vegetables, fungus, eggshells and tea leaf can be recycled, about 76% of kitchen waste is recycled by a reckoning, reduced not to be incinerated and not to go to land-fill site. In the same research data of Kyoto city, total of those items is 48.5% of kitchen wastes (2002). In Kyoto city, the leftover food accounts for 38.8%, and it is much more than Nagoya city. Table 2 shows the amount of kitchen wastes discharge par person of Nagoya city, calculated by Table 1 and total discharge amount of Figure 4, Figure 5 and Figure 6. However, these total discharge amount of kitchen waste include the waste coming from business sector like super markets, offices and so on. So, Figure 7 shows the kitchen waste flow which combustible waste is divided by household emission and business sector emission in According to Figure 7, the amount of discharged kitchen waste only from household is g par person par day in ) When food of which its waste do not go out, such as precut vegetables, account for 30% of the entire food, it becomes the discharge control of the kitchen waste of about 15.9%. There is an advantage that comes to make the quality single because kitchen waste like skin of vegetables is generated in market circulating, and to recycle easily, too. 2) When leftover food is discharged, it must be discharged as combustible waste. However, if combustible waste discharge becomes charged, the incentive to decrease waste may work. When 50% of leftover food is reduced, 1% of kitchen waste should be decreased. 3) When 30% of households in Nagoya city discharge the kitchen waste after squeezing water and drying it up, 15.5% of total kitchen waste coming from households would be reduced, because about 80% of kitchen waste is moisture. 4) There are some bio waste recycle methods, for example, composting, methane fermentation, fodder production, and so on. In Nagoya city, a lot of households have disposer and they crush their kitchen waste at their kitchen, then throw into drainage. About 20 thousand households have small composting machine but it is said that half of them give up to use the machine because they can not use produced compost in their houses. In this study and in the discussion of the team, composting is most recommended, because the method does not need high technology and does not cost too much. Also, when Nagoya city will change the way of recycle to methane fermentation system for example, the segregation of kitchen waste should be needed and easy for citizens. Therefore, for composting kitchen waste, it is suggested to segregate and collect only vegetable and fungus waste, eggshell, skin of fruits and coffee and so on. When 30% of them are collected, 14.7% of kitchen waste can be recycled. The total amount of reduced bio waste is 121 thousand tons per year, when total discharge of kitchen waste is 257 thousand tons. Sorted collection is estimated about 37.8 thousand tons. 4. POLICY RECOMMENDATION TO NAGOYA CITY Through team discussion, we summed up two recommendations. Following recommendations are the drafts, 641

5 at the time of last day of August In September 2007, we had added meetings and associated meetings with other teams, and we made final recommendation (final proposal) to all the Nagoya citizens, business sector and the city. Hence the following policy recommendation of this paper should be different from the final recommendation published at the end of September Control of discharge According to the third municipal waste management plan of Nagoya city, the target of kitchen waste recycle is 20% in Therefore, the city formed the committee for kitchen waste recycle and the committee put in the final report. The report said that the methane fermentation is the most suitable processing if the recycling of kitchen wastes is made an obligation in all households of Nagoya city. Other committee for processing technology also had same output. About control of discharge, the reports said only that some super-markets should sell vegetables, meat and so on by measure. It is considered that such a sales may control consumer s purchase too much, and now, some supermarkets sell vegetables one by one already. Now, 36.6% of household is single-person household in Nagoya city (2005). The trend of single life is on going. A lot of foods subdivided for one person will be sold even if nothing is done in the future. It means that small packaged food, precut vegetable and vegetable of selling by weight should be sold more, and kitchen waste should be reduced. It means 1) will become true. In another hand, the team decided that a charge on the solid waste should not be introduced finally. So, 2) was not become a proposal. However, the team had a consensus that school children must not leave over food in their school lunch. Drying up the kitchen waste is an important activity, too. The team proposed some way and idea to dry up the waste Recycle For households, the city collects once in a week at the waste station. Households should discharge only decided item of kitchen waste or composted food by their machines. There are 2 companies to compost bio waste in Nagoya city now, and total capacity of them is about 60 thousand tons. Therefore, Nagoya city needs one more factory or other recycling technologies in future. If such companies accept collected kitchen waste, they also sell the produced compost to farmer in other city or other prefecture. Nagoya city has only 8% of entire land of rivers, farmed land, and woods. It is impossible for Nagoya city to use all produced compost, so Nagoya city needs to ask companies to accept its kitchen waste to compost and to sell them. The waste discharged by business sector, supermarkets, can be controlled by becoming charged more; even now some of bio waste of supermarkets is recycled as compost because it is charged 20 yen per 1 kg discharge as municipal waste. In 2020,when is plan s target, bio waste of municipal waste would be reduced by 40% and more, if too much purchase was controlled, and recycle policy was done. REFERENCES 1. T.Okayama, Factor analysis to decrease municipal waste and to convert city to 3R society, R07 (2007) 2. Nagoya sound material recycle-all actors proposal conference committee, The intermediate proposal, (2007), pp (in Japanese). 3. Nagoya city and Kitchen waste recycle committee, The final proposal concerning recycling of kitchen waste, (2006) (in Japanese). 4. The Ministry of Agriculture, Forestry and Fisheries/ Synthesis food bureau/ Food Planning Section/ Planning group, (2007) 5. M.Yagishita, M.Ao, T.Okayama, S.Okuda, A.Ori, H.Koyanagi, W.Takahashi, I.Yokota, Study Report of 2006 (K1824), the Ministry of Environment in Japan, (2007), pp (in Japanese). 642