Metawater Co., Ltd.

The University of Kitakyushu

Tetsuya Yanase

Masaki Yamada

Masayuki Yamamoto

Mitsuharu Terashima

Tomoyuki Takeshita

Kosuke Kamiya

Hidenari Yasui

Natsumi Noiri

An organic wastewater treatment method that includes a raw sludge removal step, a raw sludge concentration step, a biological treatment step, an excess sludge separation step, an excess sludge concentration step, a sludge mixing step, and a methane fermentation treatment step. The treatment method further includes a sterilization step for heating and sterilizing the concentrated excess sludge upstream of the sludge mixing step. At least one among: (1) the temperature to which the concentrated excess sludge is heated during sterilization, (2) the concentration of concentrated raw sludge and/or the concentration of the concentrated excess sludge, and (3) the mixture ratio between the concentrated raw sludge and the concentrated excess sludge is adjusted according to the fluctuation in the amount of raw sludge generated and the amount of the excess sludge generated, and the temperature of the mixed sludge is controlled to a temperature suited for methane fermentation.

Organic wastewater treatment method and organic wastewater treatment device

An inside of an incinerator body into which sludge is fed is divided into a lower portion, a portion above the lower portion, and a top portion in a height direction. The lower portion serves as a pyrolysis zone for supplying fluidizing air having an air ratio of 1.1 or less together with fuel to thermally decompose the sludge while fluidizing the sludge. The portion above the lower portion serves as an over bed combustion zone for supplying only combustion air having an air ratio of 0.1 to 0.3 to form a local high temperature place to decompose NO. The top portion serves as a perfect combustion zone for perfectly combusting unburned contents. The quantity of NO generated during sludge incineration can be drastically reduced while maintaining the use quantity of auxiliary fuel at the same level as that of a conventional incineration method.

Fluidized bed incinerator and fluidized bed incinerating method for sludge using the same

Growing community of inventors

Tokyo, Japan

Tetsuya Yanase