Mitsubishi Denki Kabushiki Kaisha

Naoki Nakatsugawa

Akira Ikeda

Yasuhiro Tanimura

Masaaki Tanaka

Junji Hirotsuji

Toshiyuki Kamiya

Nozomu Yasunaga

Toshie Hiraoka

Hiroshige Konishi

Hiroto Kawahira

Shinji Nishio

Seiji Furukawa

Kenji Ezaki

Yumiko Yoshimura

A sludge treatment method allowing an improvement in a phosphorus recovery rate and sludge volume reduction by efficiently eluting phosphorus in the sludge. The sludge treatment method includes: a step of foaming a sludge-containing liquid by blowing an ozone-containing gas into the sludge-containing liquid; and a step of eluting phosphorus in the sludge-containing liquid by bringing sludge adsorbed on bubbles and a sludge-dissolving agent into contact with each other. The sludge treatment method may further include the steps of: separating the phosphorus eluted sludge-containing liquid into a phosphorus eluate and a residual sludge; and precipitating a phosphorus compound by adding a coagulant to the separated phosphorus eluate.

Sludge treatment method

Sludge treatment apparatus

A process for treating organic wastewater which comprises treating organic wastewater with ozone and successively with alkali and introducing said alkali treated organic wastewater into an anaerobic digestion tank for anaerobic digestion. Instead of the ozone and successive alkali treatments, ozone treatment in the presence of hydrogen peroxide or ozone treatment under UV radiation is applicable. Prior to introduction into the anaerobic digestion tank, the treated wastewater may be separated into solids and phosphorus is preferably recovered from the solution. Solubilization of solids in the organic wastewater and transformation of organic substances into methane are greatly enhanced and sludge to be disposed is greatly reduced. Moreover, phosphorus is efficiently eluted out and recovered from solids in the organic wastewater.

Process for treating organic wastewater and apparatus for treating the organic wastewater

An organism deposition preventing system for removing organisms propagated in water comprises: an ozonizer for generating ozone, an ozone adsorber containing an ozone adsorbent for storing ozone generated by the ozonizer, a water-jet ejector for injecting an ozonous gas produced by desorbing ozone from the ozone adsorbent of the ozone absorber into the water, and a carbon dioxide gas source means for supplying carbon dioxide gas to be injected into the water together with the ozonous gas or in synchronism with the injection of the ozonous gas into the water. A microorganism removing method for removing microorganisms propagated in water injects a mixed gas consisting of an ozonous gas and carbon dioxide gas into the water or injects carbon dioxide gas in synchronism with the injection of the ozonous gas into the water.

Microorganism removing method

A microbe propagation preventing apparatus is provided to prevent an ion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber. Further, a diffusing apparatus is provided to transform the ionic gas into bubbles so as to feed the bubbles into the water in the water reservoir.

Microbe propagation preventing apparatus

A microbe propagation preventing apparatus and a microbe propagation preventing method are provided to prevent anion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus and the method, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber. Further, a diffusing apparatus is provided to transform the ionic gas into bubbles so as to feed the bubbles into the water in the water reservoir.

Microbe propagation prenvention method

A microbe propagation preventing apparatus and a microbe propagation preventing method are provided to prevent an ion from decreasing at a time of decomposing ozone generated by gaseous discharge or ionization so as to sufficiently generate air ion, and to sufficiently prevent propagation of microbes adhering to an object by using the air ion without secondary pollution. Further, in the apparatus and the method, a gas containing the ion is supplied into water so as to prevent the microbe propagation in the water. In the apparatus, an ozone decomposing chamber is mounted to be electrically insulated from an air duct. An electrode to remove a positive ion is mounted to obtain only a negative ion, and extend a lifetime of the obtained ion. An ion supplying portion is mounted to supply an ionized gas into a space housing the object in which microbes can be propagated, and return the ionized gas to an ionization chamber. Further, a diffusing apparatus is provided to transform the ionic gas into bubbles so as to feed the bubbles into the water in the water reservoir.

Growing community of inventors

Hyogo, Japan

Naoki Nakatsugawa