Characteristic and Mechanism of Semi-Aerobic Landfill on Stabilization of Solid Waste

The details of a semi-aerobic landfill type are described and compared with an aerobic landfill type, particularly related to the characteristics of the solid waste stabilization and the stabilization mechanism. Semi-aerobic landfill is an attempt to lay the leachate collection pipe, comprising the perforated main and branch pipes and gravel, at the bottom of the landfill to discharge leachate out of the landfill as quickly as possible. This prevents leachate from penetrating into the ground water by removing leachate remaining from the bottom of the landfill. Also, oxygen in air is led into the landfill through the leachate collection pipe by heat convection resulting from differences between the inner temperature and outside air temperature. Comparative studies of the decomposition characteristics of the pollutant components in the semi-aerobic and anaerobic landfill types have been conducted by using two types of large lysimeters. Clarified differences between landfill types are as follows: (1) biodegradation of semi-aerobic type was mainly gasification dominated by carbon dioxide, (2) production decomposition of the BOD and T-N components in the seepage water in the bottom layer close to the leachate collection pipe of the semi-aerobic lysimeter was clearly evident, and (3) elution of the pollutant components not in the vicinity of the leachate collection pipe was more remarkable than the anaerobic landfill, suggesting that decomposition of the waste itself is accelerated. Takayuki Shimaoka Yasushi Matsufuji Masataka Hanashima Department of Civil Engineering, Faculty of Engineering, Fukuoka University 8-19-1 Nanakuma, Johnan-ku, Fukuoka, 814-0180, Japan E-mail: [email protected]