OCR Text |
Show Along with the rapid increase in the consumption of petroleum fuel under the rapid economic growth in Japan, the air pollution by SOx, one of the primary pollutants produced out of thermal equipments, developed into a serious problem. Since 1967, however, the pollution has been improved steadily due to the settlement of environmental standards and improved quality of fuel. While, for NOx that substituted SOx as the major concern for air pollution, the environmental standard for nitrogen dioxide (N02) was settled in 1973 and was revised in 1978, and also the standards for discharge from fixed source of air pollution (1st to 4th) were settled. Up to 1973, the environmental concentration of NOx had been in increasing tendency, but since 1974, it has been remaining almost on the same level. Moreover, the over-all limitation on NOx is now planned to the areas of excessive pollution. To NOx from thermal equipments, efforts shall be kept for further improvement, and as the counter-measure, denitration device . mainly for large sized facilities and the spplication of low NOx combustion technology primarily for middle and small sized thermal facilities will come to be required. At the occasion of oil crisis'in 1973, it was recognized again that the supply of fossile energy is not infinite, and in Japan whoes dependency on oversea energy is particularly high, the necessity for "Energy Conservation" has come to be emphasized, and the introduction of replacing energy such as LNG has been promoted. This report is to outline the thermal equipment of low energy consumption yet with low NOx discharging that we developed to cope with the present situation taking the advantage of clean combustion characteristic of city gas. Under the situation, the introduction of LNG as the primary energy has been promoted to take the place of city gas as the major secondary energy and the the data of 1978 (of Osaka Gas Co.) LNG has reached 61% and is scheduled to be increased further. s -1 - |