In an attempt to establish a deodorizing technique of malodorous exhaust gas from sewage or night soil treatment plants, an experimental study on absorptive oxidation of micro-amounts of styrene and acetaldehyde (0.1-1.0 ppm, each) with sodium hypochlorite solution was carried out, using a packed tower (60 cm of packed height), whereby the overall mass transfer coefficient (K_Ga) was examined. The following optimum conditions for a room temperature treatment were clarified; superficial gas velocity: 1.7 m/s, liquid/gas ratio: 2, pH of the absorptive solution: around 7, concentration of sodium hypochlorite solution: 1.2×10^-2 mol/l.
Under these conditions, micro-amounts of styrene and acetaldehyde were reduced up to 80, 88% of their initial amounts, respectively.

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The investigation was examined into restraint of nitrogen oxides in exhaust gas bychanging the combustion conditions as to municipal solid waste incinerators. The relations between nitrogen oxides in exhaust gas and combustion conditions ofmunicipal solid waste were investigated. It is confirmed that nitrogen oxides inexhaust gas have positive relation to the combustion temperatures and the concentrations of oxygen in exhaust gas. Hence relatively low combustion temperatureand low oxygen may suppress nitrogen oxide emission. But the concentrations of oxygen must be maintained with considerations of carbon monoxide and the soot and dust emissions because emissions of carbon monoxide and the soot and dust werencreased with the combustion under low oxygen atmosphere.

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Suspended particles released in glass manufacture were subjected to multielementanalysis by means of instrumental neutron activation method and energy dispersive X-ray fluorescence spectrometry. Suspended particles released from glass factories using combustion heating generally consist of both particles emitted from glass fusion and particles produced through fuel combustion. Elemental compositions of suspended particles emitted from glass fusion were found to be strongly dependent on the kind and recipe of raw materials and additives. Of the various metallic elements involved in suspended particles emitted from glass fusion, the elements, As, Se, Cd, Sb, Pb and so on are regarded to produce the most serious air pollution. The amount of emission of these elements to the environment is, however, quite varied from factory to factory. The replacement of oil combustion by electric furnace in an opal glass factory remarkably reduced the emission of metallic elements to the environment.

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