Silviase/jgov_v1.4_full_ann huggingface dataset:
technologies for maintaining the vehicles or effectively collecting waste are also transferred to recipient countries.

## (3) Intermediate treatment technologies, such as incineration

After being collected and transported, waste is subjected to intermediate treatment, such as incineration, composting, shredding and compaction, so as to become suitable for final disposal, including landfilling, or reuse. Thanks to such intermediate treatment, the volume of waste is reduced, stabilized and rendered innocuous.

Incineration is generally used in Japan for intermediate waste management. Because incineration reduces the volume of waste very effectively and destroys disease-causing bacteria, it is suitable for use in a country such as Japan where it is difficult to secure final disposal sites, due to limited land space, or where the temperature and humidity become high in summer. It is estimated that when incinerated, waste is reduced to approximately one-tenth of its weight and one-twentieth of its volume. In 2005, the amount of domestic waste generated was approximately 53 million tons, approximately 80% of which was incinerated.

Because the amount and quality of waste generated and the measures required for environmental preservation have changed, incineration technology as a core waste management method has developed accordingly. Because domestic waste in Japan has a comparatively high water content, advanced technology is required to achieve its complete combustion. By overcoming various challenges, incineration technology in Japan has attained the highest level in the world.

The enforcement regulations of the Waste Management Law define a structural standard for incineration plants for domestic waste, in which it is required to keep combustion gas temperatures above $ 800^{\circ} $ C for incineration, to keep the temperature of gas flowing in the dust chamber below $ 200^{\circ} $ C and to provide a waste gas treatment facility, etc. When classified by operating mode, there are three types of incineration plant: a batch fed incinerator is operated for 8 hours per day; a semi-continuous feed incineration plant is operated for 16 hours per day; and a full continuous type incineration plant is operated 24 hours per day (Fig. 2-5). When classified by the shape of the furnace, incineration plants are roughly grouped into 4 types: mechanical stoker type incinerators (Fig. 2-4) where a metal fire grate called a stoker is moved mechanically to transport and agitate waste and air is supplied from under the fire grate to burn waste; fluidized bed incinerators, where air is blown into a high-temperature sand layer to make it flow and waste is loaded into it and burnt; fixed floor furnace type incinerators where there is no fire grate and waste is burnt on a floor composed of refractory material with a flat recession; and rotary furnace type incinerators (rotary kilns) where a horizontal cylindrical incinerator, the inner surface of which is covered with refractory material, is rotated and waste is dried and burnt in it.
Fig. 2-4 Example of stoker type waste incinerator

Fig. 2-5 Trend in the number of waste incinerators classified by type of furnace

While batch fed incinerators are used in small-scale facilities, the capacity of which is generally approximately 50 tons per day, full continuous type incineration plants that are operable around the clock are installed in cities where 150 to 200 tons of waste must be treated every day. In addition, when waste is burnt continuously, it is possible to utilize waste heat stably. So, most of the 300 ton/day or greater facilities are equipped with a boiler for power generation.

As at the end of 2004, there were 1,374 domestic waste incineration plants in Japan. While
the number of plants is decreasing due to the promoted amalgamated treatment of waste as a measure against dioxins, the number of full continuous type incineration plants is increasing. Classified by type, mechanical stoker type incinerators hold a 70% or greater share (Fig.2-6).

Waste incineration is closely related to the measures adopted against hazardous substances contained in waste gas, especially dioxins, and the recovery of heat (thermal recycling) from incineration plants. This matter will be explained in detail later (see Fig. 2-17 for the reduction of dioxins). Due to these social demands, a gasification and melting furnace has recently been actively introduced. A gasification and melting furnace (Fig. 2-7) is a facility that thermally decomposes waste into gas and carbide in a gasification furnace and burns these in a melting furnace to convert them into waste gas and slag. Gasification melting furnaces have the advantages of reducing the generation of dioxin with complete high-temperature combustion, that the amount of heat held in the waste is utilized to melt and solidify ash and therefore render the ash harmless and the molten slag utilized effectively, and that only a small amount of air is required for combustion so therefore high-efficiency heat recovery with a small amount of exhaust gas is possible. Gasification melting furnace technology has evolved in Japan by the addition of various devices after it was introduced from overseas. As at the end of 2004, gasification and melting furnaces and gasifying reforming furnaces are employed in 54 facilities in Japan and the number of these is increasing every year (Fig.2-10).

Fig. 2-6 Trend in the number of waste incinerators classified by type of treatment

Source: Ministry of the Environment

Fig. 2-7 Basic flow of gasification and melting furnace
There are three types of gasification and melting furnace: a kiln type, fluidized bed type and shaft furnace type. Kiln type gasification and melting furnaces are composed of an external heat kiln type cracking furnace and a combustion melting furnace. It heats waste for thermal decomposition indirectly while shutting out air. For efficient thermal decomposition, waste is shredded into 150 mm or smaller pieces, which are dried by circulating air directly through them in order to stabilize their quality before being supplied to the thermal decomposition kiln, in which they are slowly dried indirectly for 1 to 2 hours and pyrolytically decomposed. Because the interior of the kiln is in a reducing state, free of oxygen, iron and aluminum contained in unburned material can be recovered in a state suitable for recycling.

Fluidized bed type gasification and melting furnaces burn part of the waste, which is loaded in a fluidized bed type gasification furnace, together with fluid sand, to partially oxidize the waste and pyrolytically decompose it, utilizing combustion heat. In fluidized bed type gasification furnaces, waste is dried slowly, pyrolytically decomposed and gasified at a comparatively low temperature of 500 to 600°C and at a super-low air ratio (Fig. 2-8).

Fig. 2-8 Fluidized bed type gasification and melting furnace

Shaft furnace type gasification and melting furnaces conduct both pyrolysis gasification and melting in a single furnace. The furnace is composed of a drying and pyrolysis gasification region and a combustion melting region, arranged vertically. In the gasification and melting furnace, waste is dried and pyrolytically gasified and remaining ash and unburned material are rendered as molten slug in the combustion melting region (Fig. 2-9).
Fig. 2-9 Shaft furnace type gasification and melting furnace

There are also gasifying reforming furnaces, which are technologically similar to gasification and melting furnaces. In this type of furnace, gas refined by thermal decomposition is held at a high temperature of approximately $ 1200^{\circ} $ C for two seconds or more in order to decompose tar and thus to reform it into a high-calorie gas, which is quickly cooled to $ 70^{\circ} $ C to prevent the resynthesis of dioxins. The gas obtained is refined and used for power generation or other industrial applications.

Fig. 2-10 Trend in the number of waste incinerators classified by type

Source: Ministry of the Environment
Intermediate treatment technologies, other than incineration, include technology that shreds bulky waste and segregates it into combustible material, iron, aluminum, etc., utilizing a magnet, a sieve, etc., and dehydration technology for reducing the volume of sludge and stabilizing it.

## (4) Technologies for final disposal

Waste residue, after intermediate treatment, is disposed of at a final disposal site. For industrial waste, final disposal sites are classified into three types, i.e. strictly controlled landfill site, inert controlled landfill site and controlled landfill site, according to the type of waste to be disposed of. Various technologies are used for stable, high-technology construction, to treat leachate, etc.

In strictly controlled landfill sites, industrial waste that contains a hazardous substance, such as metal, which does not meet the criteria stipulated by the applicable law, is disposed of. In order to isolate hazardous substances from nature, strictly controlled landfill sites are enclosed in 35 cm or thicker reinforced concrete to completely isolate the waste contained in it from the environment. Furthermore, in order to prevent the inflow of rainwater, it is fitted with a cover (roof, etc.) and rainwater drainage system (open channel) (Fig. 2-11).

Fig. 2-11 Strictly controlled landfill site

* Drawn based on the Ministry of the Environment ordinance for the final disposal of waste

Source: Japan Environmental Sanitation Center

Least controlled landfill sites receive industrial waste that cannot be decomposed, for example, waste plastic which has no hazardous substance, organic matter, etc. adhered to it, waste metal, waste glass, and rubble. Because industrial waste such as waste plastics contains no water and is not decomposable, it generates no water, no methane gas, etc. and therefore does not contaminate the surrounding environment. Therefore, this type of landfill site does not require seepage control work to isolate the site from the outside world or facilities for collecting, draining and treating seepage water (surface water that permeates into the site) (Fig. 2-12).
Fig. 2-12 Inert controlled landfill site

Source: Japan Environmental Sanitation Center

In controlled landfill sites, industrial waste that can be disposed of only in strictly controlled landfill sites, or industrial waste other than that which can be disposed of in inert controlled landfill sites, is disposed of. According to the decomposition of waste or the elution of metal, retained water (the water held in the waste disposed of or the surface water that permeates into the site) and gas are generated. In order to prevent retained water from contaminating groundwater, the landfill site is isolated from the outside by means of seepage control, such as a liner sheet. The retained water generated in the landfill site is collected in drain pipes to be treated in a treatment facility before being discharged.

For the landfill disposal of general waste, where the residue of incinerated waste is mostly disposed of, in general, landfill sites equivalent to controlled landfill sites are constructed (Fig. 2-13).

Fig. 2-13 Controlled Landfill site

Source: Japan Environmental Sanitation Center
Example of final disposal site with roof (Takasaki General Waste Final Disposal Site in Miyakonojo-shi) Source: Research Committee for Closed System Disposal Facilities

Recently, in order to prevent the waste disposed of in landfill sites from contaminating the surrounding environment and thus to improve the reliability of final disposal sites, technical development has progressed actively, such as high-technology seepage control works and storage functions. For example, a final disposal site with a roof can reduce the generation of leachate and prevent the diffusion of odors as well as prevent waste being dispersed. In this way, affecting the surrounding environment can be avoided. In addition, an electric water leakage detection system for liner sheets was developed. This system detects water leaks, should these occur, with electrodes arranged near the liner sheet and provides feedback to the administrative building. With this system, even if the liner sheet should break, any pollution of the surrounding environment, such as groundwater, can be avoided.

Furthermore, technology is now under development that removes waste already disposed of in a final disposal site and segregates and transports it in such a manner as to match the acceptance conditions (for example, grain size, physical properties, etc.) of a resource recovery facility for the purpose of re-securing a space for landfill and reviving the final disposal site.

## (5) Technologies for making the waste flow transparent

Various other technologies are also used at waste management sites. Of these, a technology that accurately ascertains and manages the flow of waste and thus makes it transparent is effective for preventing illegal dumping. A representative example of this technology is an electronic manifest.

The manifest system was established so that waste-generating businesses can accurately ascertain and manage conditions throughout the distribution flow of industrial waste. In this system, when a waste-generating business consigns industrial waste to a collecting and transporting business, or when a collecting and transporting business transfers industrial waste to a waste management business, a management form (manifest sheet), in which the type and quantity of industrial waste, the name of the waste-generating business, the name of the collecting and transporting business and the name of the waste management business are recorded, is handed over to the collecting and transporting business and the collecting and transporting business fills in the manifest sheet (with a receipt stamp of the collecting
and transporting business, the confirmation of the completion of transport, a receipt stamp of the waste management business, the confirmation of the completion of disposal, etc.) and returns a copy of the manifest sheet to the waste-generating business. Revisions to the Waste Management Law made this system mandatory for industrial waste under special control from April 1993 and for all industrial waste from December 1998, when disposal is consigned.

The 1997 revision of the Waste Management Law introduced an electronic manifest system, in addition to the conventional paper manifest. The electronic manifest system not only contributes to rationalizing information management by waste-generating businesses and waste management businesses but also stores the data on a network, making it impossible for people engaging in illegal dumping to destroy the manifest. There were 7,784 subscribers to the electronic manifest system as at the end of March 2007. Thus, the use of electronic manifests is still low compared to paper manifests, so it is necessary to promote the use thereof.

As the target value for spreading the electronic manifest system, 50% was determined in the government's New IT Reform Strategy (in January 2006, by the IT Strategy Headquarters). According to this determination, various activities are being conducted to enlighten waste-generating businesses, waste management businesses and administrative authorities and spread the system (Table 2-1, Fig. 2-14).

Table 2-1 Progress of subscription and registration to the electronic manifest system

FY	The number of Subscribers	Breakdown of subscribers	Cases annually registered to manifest
Waste-generating business	Collecting and transporting business	Waste management business
2003	2,001	487	785	729	812,140
2004	2,978	1,019	1,009	950	1,137,785
2005	3,834	1,291	1,327	1,216	1,621,975
2006	7,784	4,083	1,921	1,780	2,388,069

Source: Japan Industrial Waste Technology Center

Fig. 2-14 Electronic manifest system

Source: Japan Industrial Waste Technology Center
January 1992. The amount of mercury contained in batteries marketed in Japan today has thus been greatly reduced.

On the other hand, fluorescent bulbs are commonly used for lighting in Japan and the annual production of these amounts to approximately 400 million pieces. The radiation of fluorescent lamps utilizes the discharge phenomenon that takes place when a current flows through mercury vapor, so fluorescent lamps contain small amounts of mercury.

In order to prevent mercury from being dispersed in the environment when waste batteries and fluorescent lamps are disposed of, these are collected for recycling. Many local authorities participated in the Liaison Meeting for the Amalgamated Treatment of Waste Batteries, etc. of the Japan Waste Management Association to cooperate in collecting segregated waste batteries and fluorescent lamps and consigning these to waste management businesses for treatment and disposal (recovery and recycling of mercury). In 2005, 200 kg of mercury was recovered from 5,000 tons of waste fluorescent lamps (see Table 2-2).

Table 2-2 Trend in the recovered amount of waste fluorescent bulbs and mercury

2001	2002	2003	2004	2005
Amount recovered (t)	4,300	4,400	4,800	4,600	5,000
Amount disposed of (t)	2,303	2,196	2,555	2,345	2,470
Amount of mercury recovered (kg)	172	176	192	184	200

Source: Compiled by the Ministry of the Environment based on the material of the Japan Waste Management Association

Waste fluorescent bulbs are shredded in the course of their disposal so that mercury will not be dispersed in the environment and are separated into glass, aluminum base parts, fluorescent material and sludge, which contains mercury. Glass and aluminum parts are recycled as valuable resources while the sludge containing mercury is subjected to heat treatment to recover the mercury. Recovered mercury is refined and recycled as metal mercury or a mercury compound for fluorescent lamp material (Fig. 2-15).

Fig. 2-15 management flow of waste batteries and waste fluorescent bulbs for recycling
## Column

# Reduction and transparency of hazardous substances contained in products

A major objective of waste management is to prevent environmental pollution by removing hazardous substances contained in waste. However, it is preferable to minimize hazardous substances contained in waste that is brought into a waste management facility or to minimize the substances that cause secondary pollution. Namely, to reduce hazardous substances in society as a whole, hazardous substances need to be controlled at the product manufacturing stage.

With this preventive point of view, the EU enforced the RoHS Directive in July 2006. RoHS is an abbreviation for “Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment”, which regulates the content of specified hazardous substances in electrical and electronic equipment. The following six hazardous substances are specified: Pb (lead), Cd (cadmium), Cr(VI) (hexavalent chromium), Hg (mercury), PBB (polybromobiphenyl) and PBDE (polybromodiphenyl ether). Excluding exceptional cases, no product whose content of any of the six substances exceeds the criteria value can be sold within the EU’s borders.

In Japan, too, various activities are conducted to promote proper recycling of products that contain hazardous substances, such as the management of substances that, if contained in products, may degrade the quality of recycled resources or damage the recycling process, and the provision of appropriate information by indication, etc. Specifically, based on the Law for the Promotion of Effective Utilities of Resources, it became mandatory from July 2006 to manage specified chemical substances contained in applicable products and to take measures for providing information, including indication, by a method based on J-Moss (JIS C0950: Marking for the presence of specific chemical substances for electrical and electronic equipment). While the RoHS Directive regulates the sale of products that breach the standard, the Law for the Promotion of Effective Utilities of Resources made it mandatory to indicate the orange mark for specified chemical substances' being contained and to provide information via a website if a product exceeds the criterial value in the content of specified chemical substances (the same substances as the RoHS Directive). In addition, while the RoHS Directive applies basically to all electrical and electronic equipment, the scope of the Law for the Promotion of Effective Utilities of Resources is limited to seven products, including air conditioners and refrigerators.

Mark for specified chemical substances' being contained
## (2) Dioxins

Dioxins are by-products that are generated naturally when material is incinerated. Various activities have been conducted to date against dioxins being generated when waste is incinerated (Fig. 2-16).

Fig. 2-16 Chemical Structure of Polychlorinated Dibenzo-p-dioxin

Note: A chlorine atom is bound to the numbered section.

## Column

## Coexistence of the reduction of dioxins and power generation from waste

While it is necessary to reduce the amount of dioxins emitted from waste incinerating facilities, it is also necessary to introduce and expand power generation from waste as a way to cut $ CO_{2} $ emissions. Various measures are being taken, including power utilities' purchasing surplus power of waste power generation and the introduction of the RPS system (the Special Measures Law for the Utilization of New Energy, etc. by Electric Power Suppliers).

To prevent dioxins at waste incinerating facilities, rapid cooling to $ 300^{\circ} $ C is needed, in addition to increasing the combustion temperature and securing the retention time. There was concern that the slow cooling of exhaust gas by the boiler, which is necessary for power generation, may cause the re-synthesis of dioxins, but this problem has been solved by spraying activated carbon in the after-flow, installing a catalytic reaction tower, etc. Today, high-efficiency power generation is possible while reducing dioxins.

Thanks to these measures, the amount of dioxins emitted in 2004 from waste incinerating facilities in Japan was reduced by 98% or more, compared with 1997, while the electricity generated from waste increased 2.2 times. These new technologies are the core 3R technologies for waste management in Japan, where municipal waste is mostly incinerated, and are attracting attention worldwide.

As measures against dioxins, in 1990 the Japanese government laid down guidelines for preventing the generation of dioxins related to waste incinerating facilities (the old guidelines), which were revised in 1997 as new guidelines. According to these guidelines, measures have been taken to control waste incinerating facilities. In 1999 the Law concerning Special Measures against Dioxins was enacted and in order to prevent and reduce environmental pollution by dioxins, an environmental quality standard was established as the basis for measures against dioxins, and regulations on exhaust gas and waste water and measures for contaminated soil were stipulated. For example, for dioxins generated in a waste incinerating facility, the emission standard was determined to be 0.1 ng-TEQ/m $ ^{3} $ N (for incinerators with a 4 t/h or larger capacity). To meet these regulations, various activities have been conducted and the amount of dioxins emitted in 2003 from waste incinerating facilities has been