### c. Recycling/reusing stage

The amount of circulative resources reused in fiscal 2007 was 3 million tons; this does not include resources sold as used commodities.

The reused articles referred to are made up of reused tires and returnable bottles such as beer bottles and milk bottles.

### d. Circulation and recycling stage

The total of circulative resources reused directly and resources reused after intermediate processing or recycling processing were carried out, amount to 240 million tons circulative resources being recycled. This means 41% of generated wastes were recycled: this figure includes waste oil and waste wood reused as fuel.

The most typical items are 60 million tons of debris that are reused as alternative material of nonmetal mineral resources (reclaimed broken stone or reclaimed asphalt mixture) and 50 million tons of slag that are similarly reused as alternative materials of nonmetal mineral resources (raw materials and fuels of cement and road bed materials).

### e. Heat recovery (energy recovery)

When considering the amount of wastes subject to heat recovery during incineration disposal, the major part of municipal waste is used for heat recovery in the form of electric power, steam or heated water, and the electric power generated by the recovered heat in the incineration facilities amounted to 6.9 billion kWh. (Refer to Section 2, 4(2))

## (b) Characteristics of utilization of each circulative resource

It is important also to check the breakdown of circulative resources, for example, the increase or decrease of nonmetallic mineral type resources such as soil and rocks may have a large impact on the total amount of natural resources input in the material flow, because such resources represent the major part, also the increase of biomass type resources is desirable when they are collected with careful consideration to the environment so that sustainable use is possible. The breakdown of the total amount of natural resources input by characteristic and by nation are shown in the Figure 2-5 and Figure 2-6.

In addition, the characteristics of how the circulative resources generated in our country are cyclically used are shown as follows in four classifications (Figure 2-7).

### a. Biomass type circulative resources

The biomass type circulative resources account for 54% of the entire amount of waste generation. Their contents are livestock excrement, organic sludge derived from water processing in the sewage works or manufacturing, wood wastes derived from construction sites and the manufacturing process of wood products, and household kitchen waste (garbage).

Because biomass type circulative resources contain a high proportion of water and organic substances, it is characteristic that the rate of reduction volume during incineration and dehydration is high, with the natural reduction rate to generation being 26%, the cyclical use rate 17%, the volume reduction rate 55% and a final disposal rate of 3%. The major usage of cyclical use is for compost and feed in agriculture. Besides this, polluted mud is used for brick, and wood waste for reproduction wood board. The input amount of biomass type resources in our country is 190 million tons; the amount of cyclical use is 80 million tons, therefore, the proportion of the cyclical use in the total material input of biomass type resources is 22%.

When looking to increase the cyclical use of biomass type circulative resources and decrease the amount of final disposal, it is useful to consider the following factors, the expansion of acceptance of fertilizer and feed in the agriculture area, the transformation to energy in methane fermentation facilities, and the promotion of the reduction of residual substances by incineration.

### b. Nonmetal mineral type circulative resources

Nonmetal mineral (soil and rocks) type circulative resources account for 36% of the entire amount of generation of wastes. Their contents are, debris from construction sites, slag from the iron and steel manufacturing/non-ferrous metal/cast metal industries, non-organic sludge from construction sites and water purification plants, and glass bottles from households and restaurants.

As nonmetal mineral type circulative resources are inorganic material with a stable nature, about 70% are recycled; the cyclical use rate compared to generation is 67%, the reduction rate is 26% and the final disposal rate is 7%, but on the contrary, however, the final disposal rate is rather high. The major cyclical use is in civil engineering and construction such as materials for road base and cement. The input amount of nonmetal mineral type resources in our country is 670 million tons, the amount of cyclical use is 140 million tons, therefore, the proportion of cyclical use against the total material input of nonmetal mineral type resources is 18%.

When looking to increase the amount of nonmetal mineral type circulative resources and decrease the amount of final disposal, factors to consider are expanding the acceptance of such materials in civil engineering and construction e.g. road base material and cement material as fertilizer. However, demand for civil engineering and construction is and will be on a declining trend in the future, it will be necessary to examine the expansion of cyclical use in other areas and to contemplate the examination of reduction strategies for final disposal.

### c. Metal type circulative resources

Metal type circulative resources account for 7% of the entire amount of generation of wastes. Their contents are, scrap material from construction sites, scrap metal from iron and steel manufacturing/non-ferrous metal industries, metal processing scrap from machinery and appliances manufacturing industries, and such used household products as metal cans and home electric appliances.

Figure 2-5 The Breakdown of Natural Resources, etc.