Mitsubishi Denki Kabushiki Kaisha

The Japanese Research & Development Association for Environment Friendly Processing in Food Industry

Junji Hirotsuji

Shigeki Nakayama

Yasuhiro Tanimura

Tateki Ozawa

Hisao Amitani

Hiroshi Yuge

Toshiyuki Kamiya

Nozomu Yasunaga

Seiji Furukawa

Masaki Kuzumoto

Naoki Nakatsugawa

Masao Nozaki

Osamu Matsuoka

Satoshi Ueyama

Yoshitaka Kawaai

Yoshitaka Hasegawa

Brahim Messaoudi

Miki Kamimura

Satoru Shiono

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

In a process of eluting phosphorus from sludge into a liquid phase and recovering the phosphorus efficiently, cell walls of microorganisms in the sludge are ruptured by a process selected from crushing sludge (for example, treating with an ultrasonic wave homogenizer), treating with ozone, and treating with heat. Then the liquid phase is treated with alkali, thereby eluting the phosphorus into a liquid phase efficiently in a short time. By coagulating and precipitating, the phosphorus eluted into the liquid phase is recovered.

Process of eluting and recovering phosphorus from sludge

A water treatment apparatus dissolving an oxidizer in wastewater at a fast speed and at a high efficiency to decompose substances at a high decomposition rate. The apparatus includes an ultraviolet radiation part having an elongated tubular configuration, and receiving an axially extending ultraviolet radiation unit with a space between an inner peripheral surface of the ultraviolet radiation unit and the ultraviolet radiation unit to pass wastewater; and an oxidizer mixing part disposed adjacent to and upstream of the ultraviolet radiation part for mixing an oxidizer with the wastewater. The ultraviolet radiation unit irradiates the wastewater with ultraviolet light to decompose the substances to be treated in the wastewater.

Water 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

A method of treating water containing a nitrogen compound, and an apparatus of treating water containing a nitrogen compound at high speed without using a biologically unstable treatment causing eutrophication in lakes and swamps. The waste water is introduced into an adsorbing tank that is filled with a zeolite, only nitrogen components are adsorbed by the zeolite, a solution containing hypochlorous acid or hypobromous acid is introduced into the adsorbing tank, and the nitrogen adsorbed in the zeolite is decomposed by the hypochlorous acid or the hypobromous acid.

Method and apparatus of treating water containing a nitrogen compound

An electric energy conversion/storage system includes an ozone generating means ( ) for producing an ozonized gas from a raw material gas containing oxygen by utilizing electric energy, an ozone adsorbing/desorbing means ( ) for adsorbing ozone contained in the ozonized gas and desorbing ozone from the adsorbed state, a gas circulation system for causing the raw material gas and the ozonized gas to flow through the ozone generating means ( ) and the ozone absorbing/desorbing means ( ) while feeding back to the ozone generating means ( ) a residual part of the oxygen gas remaining after adsorption of ozone, a coolant supply means ( ) for cooling the ozone adsorbing/desorbing means ( ), and an ozone discharging means ( ) for taking out an ozone containing gas which contains ozone molecules from the ozone adsorbing/desorbing means ( ) to thereby supply the ozone containing gas to an ozone consumer ( ). The ozone discharging means ( ) includes an ozone concentration control means ( ) for enabling supply of the ozone containing gas to the ozone consumer ( ) substantially at a predetermined ozone concentration and substantially at a predetermined constant flow rate.

Electric energy converting/storing method

An electric energy conversion/storage system includes an ozone generating means ( ) for producing an ozonized gas from a raw material gas containing oxygen by utilizing electric energy, an ozone adsorbing/desorbing means ( ) for adsorbing ozone contained in the ozonized gas and desorbing ozone from the adsorbed state, a gas circulation system for causing the raw material gas and the ozonized gas to flow through the ozone generating means ( ) and the ozone adsorbing/desorbing means ( ) while feeding back to the ozone generating means ( ) a residual part of the oxygen gas remaining after adsorption of ozone, a coolant supply means ( ) for cooling the ozone adsorbing/desorbing means ( ), and an ozone discharging means ( ) for taking out an ozone containing gas which contains ozone molecules from the ozone adsorbing/desorbing means ( ) to thereby supply the ozone containing gas to an ozone consumer ( ). The ozone discharging means ( ) includes an ozone concentration control means ( ) for enabling supply of the ozone containing gas to the ozone consumer ( ) substantially at a predetermined ozone concentration and substantially at a predetermined constant flow rate.

Electric energy converting/storing system

An ozone supplying apparatus comprising an ozone generator for generating ozonized oxygen from raw material oxygen, an adsorption/desorption device for adsorbing and storing ozone from ozonized oxygen and desorbing the ozone, and an ozone desorbing means for desorbing the adsorbed and stored ozone for supply, the apparatus being arranged to return oxygen to the ozone generator after desorbing ozone therefrom by the adsorption/desorption device, and to desorb and supply ozone from the adsorption/desorption device, wherein the adsorption/desorption device includes a plurality ozone storing portions filled with an adsorbent, and a liquid storing portion for filling a temperature medium to an outer peripheral surface of the ozone storing portion.

Ozone supplying apparatus

An ozone producing apparatus includes an ozone generator for generating ozonized oxygen, an adsorption/desorption tower for adsorbing and storing ozone from the ozonized oxygen, and an ozone desorbing device for desorbing adsorbed and stored ozone for supply, wherein the apparatus further includes an oxygen gas supply tank for supplying oxygen to the adsorption/desorption tower at the time that desorption is started and an oxygen gas flow rate adjusting valve for adjusting flow rate of the oxygen gas to, be supplied. Ozone injection can be made definite, and the apparatus is economical in the aspect of both initial and running costs. It presents great effects of preventing slime adhesion and can also limit generation of oxidants even when applied to sea water.

Ozone producing apparatus

During a waste water treatment process such as an activated-sludge process using microorganisms, the present invention ozonizes a microorganism-mixed liquid. It reduces the amount of microorganisms remaining, prevents a microorganism floc from sedimenting inappropriately, and recovers appropriate sedimentation while maintaining treatment performance. A waste water ozonization apparatus according to an embodiment of the present invention can include a sludge drawing pump which draws a microorganism-mixed liquid from an aeration vessel; an ozonizer for generating ozone gas which reacts with the microorganism-mixed liquid; an ozonization vessel which injects the ozone gas generated by the ozonizer into the drawn microorganism-mixed liquid; an ozonized-sludge channel that returns the ozonized microorganism-mixed liquid to the aeration vessel; and a control section for intermittently performing an ozonization operation.

Waste water ozonization process and apparatus

An ozone supplying apparatus comprising an ozone generator for generating ozonized oxygen from raw material oxygen, an adsorption/desorption device for adsorbing and storing ozone from ozonized oxygen and desorbing the ozone, and an ozone desorbing means for desorbing the adsorbed and stored ozone for supply, the apparatus being arranged to return oxygen to the ozone generator after desorbing ozone therefrom by the adsorption/desorption device, and to desorb and supply ozone from the adsorption/desorption device, wherein the adsorption/desorption device includes at least one ozone storing portion filled with an adsorbent, and a liquid storing portion for filling a temperature medium to an outer peripheral surface of the ozone storing portion.

Hydrogen peroxide in a hydrogen peroxide reservoir is supplied to an effluent. Ozone gas generated in an ozone generating apparatus is delivered through branched piping to two ozone supplying points and is supplied to the effluent. The ozone and the supplied hydrogen peroxide react to generate hydroxyl radicals. The hydroxyl radicals react with the materials in the effluent to decompose and remove them.

Method for ozone treatment using a mixture of ozone and hydrogen peroxide

An ozone producing apparatus comprising an ozone generator for generating ozonized oxygen, an adsorption/desorption tower for adsorbing and storing ozone from the ozonized oxygen generated by the ozone generator, and an ozone desorbing means for desorbing the adsorbed and stored ozone for supply, wherein a reducer storage for storing reducer therein is connected to the adsorption/desorption tower through a switch valve which is opened when the ozone producing apparatus is under an abnormal driving condition. Desorbed ozone can be safely treated even in the case of power failure or an abnormal driving condition in which high pressure or high temperature exists in the adsorption/desorption tower.

Ozone producing apparatus responsive to an abnormal driving condition

A method for preventing biofouling in a cooling water system wherein ozone of high density is intermittently injected into a circulating line of a cooling water system in which cooling water is made to circulate in a closed system which includes a cooling tower and a heat exchanger. There is further disclosed an apparatus for preventing biofouling in a cooling water system, comprising an ozone generator for producing ozone, an ozone reservoir for temporarily storing the produced ozone, and an ozone injector for injecting the stored ozone into a circulating line of a cooling water system. Biofouling can be economically and reliably prevented.

Growing community of inventors

Tokyo, Japan

Junji Hirotsuji