Activated coke that has been developed as the material for NOx and SOx removal was applied to the advanced treatment of incineration flue gas of municipal solid waste. The material used is a denitrification catalyst and simultaneously has the capability to adsorb trace organic compounds. The treatability of some types of airborne pollutants was investigated in this study. The adsorption capacity of 1, 2-dichlorobenzene at ppm levels by activated coke was about 1 / 10 of that by activated carbon. The capacity decreased by approximately 40% with a 30°C increase in temperature above 120°C. Moreover, adsorption decreased with an increase in gas moisture. The extent of moisture influence was almost the same for 20% and 40% moisture content. Effects of temperature, moisture and space velocity (SV) on the breakthrough time of 1, 2, 3, 4-tetrachlorobenzene at ppb levels were quantitatively investigated, and the adsorption capacity was obtained. NOx reduction by activated coke increased with an increase in temperature and with an decrease in SV. It was found that a removal efficiency of 60 % or more was possible at temperatures under 200°C.

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In this study, an environmental performance evaluation and its environmental audit was carried out for eight main or branch offices in Hiroshima City. Each location was studied selected as an experimental system, based on the theory that the ⌈system⌋ and the ⌈environment⌋ are distinct from one another. Incoming parts (incoming materials, deliveries and incoming copy paper), circulation (one sided paper both produced and consumed, FAX), and outgoing parts (outgoing materials, trash to be burned and to be recycled) were considered as subjects and measured in the investigation.
The measurement for each office was performed for a period of one week between June and September 1995. Based on the measurement results, the incoming and outgoing materials were systematically arranged, and an environmental balance accounting, which is the basic data for environmental audit, was presented. Moreover, taking the environmental balance accounting as a basis, a flow diagram of the materials was drawn, and evaluations of various environmental effects and related improvements were carried out in the eight offices. In these evaluations, the level of CO₂ emission was used as an index, and was simulated using the LCA technique. The results for the CO₂ emission level in the eight offices were : four of them had an approximate 30% reduction ; two less than a 10% reduction ; while the remaining two showed almost no change at all;
Although there were different results for each office in these evaluations, overall approximately a 60% of reduction for CO₂ was possible for each of the eight offices.

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HCl and S0₂ concentrations in flue gas from municipal waste incinerators were investigated for different removal equipment for HCl and SO₂. The emitted and removed levels of HCl and SO₂ from the municipal waste incinerators in the ward areas of Tokyo and throughout Japan were estimated.
When the removal equipment was not used, the mean concentration of HCl ranged from 300 to 650 ppm. This range was dependent on the sorting and collection method of plastics in the waste, gas temperature control methods, and dust removal methods. The mean concentration of SO₂ ranged from 44 to 63 ppm, and was dependent on dust removal methods.
In the case where the calcium powder injection method and the electrostatic precipitator (EP) were adopted, the mean concentrations of HCl and SO₂ ranged from 200 to 410 ppm, and 30 ppm, respectively. In the case where EP and a wet scrubber were adopted, the mean concentration of HCl ranged from 6 to 12 ppm, and the mean concentration of SO₂ was about 2 ppm.
In the ward areas of Tokyo, the amount of incinerated waste in 1994 increased by 1.4 times over that for 1980. However, the amount of HC2 and SO₂ that was emitted from municipal waste incinerators in 1994 was slightly higher than those in 1980 because of the adoption of removal equipments.
In Japan overall, the emitted amount of HCl and SO₂ from municipal waste incinerators in 1992 was estimated to be 9.1×10⁴ t/y and 1.8×10⁴ t/y, respectively. And the removed amount was estimated to be 7.6×10⁴ t/y and 2.0×10⁴ t/y, respectively.

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The physical and mechanical properties of regenerated LDPE mixed with sludge ash were investigated to evaluate the reutilization feasibility for construction materials. As a result, the physical properties of regenerated plastics get elevated by the ash particles dispersed well to be acted as nuclei, at an ash content ratio of 20%. However, at the content ratio higher than 20%, the physical properties declined because of gathered ash particles. Especially, as the content ratio increases to 40 or 50%, a number of cracks, holes, and lumps of crystalline polymer were found in the SEM photographs. This causes the decline of physical properties and an increase in water absorption rate. The maximum values of compressive-, tensile-, and bending-strength were obtained by adding ash with a content ratio of 20% to 30%. Compared with the standard design strength of ordinary concrete, it was ascertained that a regenerated LDPE mixed with an inorganic ash filler could be used for construction materials.

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Artificial zeolite (A.Z.) having a high cation exchange capacity (C.E.C) is formed by treating coal fly ash (fly ash), discharged from a coal-fueled power plant, with an alkali solution.
This study was carried out to determine the chemical composition of fly ash suitable as a raw material for A.Z. and to establish the process conditions to form A.Z. having a high C.E.C. from fly ash.
The results can be summarized as follows :
(1) The C.E.C. of A.Z. depends on the non-crystalline Al₂O₃ content in flyash.
(2) The C.E.C. of A.Z. and the non-crystalline Al₂O₃ content in fly ash increase as the content of Na₂O+K₂O and/or Al₂O₃ in the fly ash increase.
(3) A.Z. with a the high C.E.C. is formed through the addition of a suitable Al resource in the process of treating fly ash with an alkali solution.

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In order to reduce the environmental effect of recycling systems, the SLCA method (Service Life Cycle Assessment) was proved to be more effective than PLCA.
In this paper, we outline the SLCAmethod when used with recycling systems and make clarify the differences between the PLCA and SLCA method.
We made a case study in a city by using two recycling systems with the SLCA method.
The results of our study showed that recycling systems (the method of classification, collection frequency, transporting distance) must be assessed from an environmental standpoint.

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