Disposal of waste material, especially medical waste, has become a more serious problem in modern society because of its poor combustibility and unsanitary nature. In order to solve this problem, a compact and odorless incinerator has been developed. It furnishes an innovative solution to the problem bydisposing of waste materials at the site of its generation.
In this incinerator, waste material is decomposed into gas by means of microwave energy. Catalyst combustion and flame combustion are used in the burning process because of the wide range of gas concentrations generated by thermal decomposition. The activated temperature of this catalyst corresponds approximately to the temperature of the thermal decomposition. Therefore, in order to purify the generated gases completely, it is necessary to heat the catalyst to the same temperature as the thermal decomposition in order to keep the generated gases in the gaseous phase. In this way, a sample waste incinerator has resulted in minimal emission of harmful materials.

View full abstract

In Japan, extensive statistics on waste management practices are compiled every year from nationwide surveys. This paper shows, however, that these statistics do not provide the precise data to accomplish optimal so-called integrated solid waste management. The reason is: in the statistics, household waste and industrial waste, quite different in composition, are confused when the waste amounts are calculated. In past studies on waste generation, data from these statistics was employed, so the household waste stream had not been successfully elucidated with generality. By studying documents of waste management from many municipalities, a questioning form of the nationwide survey is proposed in this paper. The typical household waste stream is also shown, with Sapporo as an example.

View full abstract

Rapid increase of paper production and consumption and resultant increase in paper waste in turn, give larger loads to the municipal solid waste management system. In this study, a mathematical model is developed by describing mass-balance relationships of paper resources in each elemental process in Japanese socio-economical systems such as import, export, production, consumption, recycling and waste treatment of each specific paper resource.
The main results obtained under the limits considered, can be summarized as follows; (1) The mathematical model is promising for evaluation of actual paper resource flow. (2) The recently decreasing trend in wastepaper recovery has the promising effect of promoting wastepaper recovery and decreasing paper waste generation, which are generally pointed out recently, were quantitatively examined using the mathematical model and fitted parameters.

View full abstract