Control of the Use of Mercury in Production Processes and Products
There are several production processes using mercury. Typical processes are those to produce caustic soda, chlorine and vinyl chloride monomer. In Japan, however, all of these processes have now been replaced by alternative processes which do not use mercury.
Cosmetics, agrochemicals and other products, the risk of which to human health is high because of the use of mercury, are subject to individual regulations which either totally prohibit the use of mercury or stipulate the upper limit of the mercury content (see Table 2).
The Act Concerning Promotion of the Procurement of Eco-Friendly Goods and Services by the State and Other Entities (hereinafter referred to as the "Green Procurement Act") aims at promoting the procurement of goods and services to contribute to reducing the environmental load in the public sector. The criteria for the procurement items specified by the Basic Policy Concerning the Procurement of Eco-Friendly Goods and Services, in turn based on the said Act, include criteria relating to mercury, thereby facilitating the development and wide use of mercury-free products and reducing the mercury content of products (see Table 3).
In addition, the national government has actively implemented measures designed to facilitate the shift of the caustic soda and chlorine production processes to those which do not use mercury and to reduce the amount of mercury in batteries.
Environmentally Sound Management of Waste
Mercury is present in the dust, sludge and other waste generated by facilities combusting fossil fuel, metal refineries and waste incineration plants. To ensure the appropriate disposal of such waste, waste with a mercury concentration above a specified level is classified as industrial waste requiring special management (Table 4) and is subject to the disposal standards. In short, the transportation and disposal of such waste must meet stricter regulations than ordinary waste. In regard to the final disposal of industrial waste requiring special management, disposal at ordinary controlled type landfill sites is possible as long as waste containing mercury is treated to show the mercury concentration equal to or below the acceptance criteria shown in Table 4. When waste is still judged to be industrial waste requiring special management after treatment, it is a compulsory requirement for such waste to be landfilled at strictly controlled landfill sites where the landfill area is completely shut off from public water areas and groundwater by a concrete
base and partition walls.Mercury Demand Reducttiion iin Producttiion Processes and Productts by IIndusttriies
Figure 8 shows that domestic demand for mercury reached a peak in 1964 in which approximately 2,500
tons of mercury were consumed. After that, owing to the introduction of technologies to reduce the mercury
use and shift to mercury free alternatives, its demand has declined drastically. In recent years, mercury
demand in Japan is approximately 10 tons per year.
This section describes the efforts in Japan to reduce the mercury demand for production processes and
products.
Mercury Demand Reduction in Caustic Soda Production
Caustic soda (sodium hydroxide: NaOH) is a typical strong alkaline substance. It is widely used as a basic
material for the dissolving and refinement of metal, removal of impurities, bleaching, neutralisation and
softening. Its further use for the production of chemical fibres, dissolving and bleaching of pulp and as a
raw material for soap and detergent signifies its status as an essential substance for our daily life.