| 摘要 |
<p>PURPOSE:To subject the excretion matters of cattle to the optimum aeration process, by arranging a plurality of aerating means along the same direction in line with the circumferential direction of a slurry tank in a manner such that they cross a circumferential direction in the slurry tank and incline toward the center of the slurry tank, and providing a defoaming means. CONSTITUTION:A liquid containing crude excretion matters of cattle in a sub pit 5 is sent through a spouting pipe 9 and a liquid-supply pipe 11 into a slurry tank 4. When the slurry tank 4 is filled with water in winter, a vertical shaft pump 8 is intermittently driven, and a gate valve 6 is also intermittently opened or closed in response to the operation of the vertical shaft pump 8. By the operation of an aerating means 14, a gas-liquid mixture is let flow as shown in C, so that an amount of air necessary for aerobic fermentation is supplied to the excretion matters of cattle in the slurry tank 4 in the level of from the bottom of the vessel to the surface of the liquid. Bubbles formed by the aeration is defoamed by the operation of a defoaming machine 21. Said machine 21 may be intermittently driven, when the bubbles are formed to an unrising extent.</p> |
