Hitachi Plant Technologies, Ltd.

Hitachi Plant Engineering Construction Co., Ltd.

Other

Sapporo Breweries Limited

Japan Sewage Works Agency

Hitachi, Ltd.

Tatsuo Sumino

Kazuichi Isaka

Hiroyoshi Emori

Takako Ogasawara

Hiroki Nakamura

Naoki Abe

Kazuhiko Noto

Nobuko Hashimoto

Naomichi Mori

Masataka Kasai

Masaaki Shirai

Koutarou Aoyama

Yuya Kimura

Hajime Ikuta

Satoshi Tsuneda

Ho-Dong Park

Takayuki Kouno

Takayuki Nakamura

Yutaka Mitani

Syuzo Koike

Yasuhiro Oki

Minoru Kayanoki

Yuuko Fujii

Masahiro Kon

Yasutomo Ohtake

Kazuo Nakajima

Tsutomu Minaki

Tamio Igarashi

Ryuichi Matsuyama

Takashi Kimata

Shoko Kitasaki

Minoru Tada

Syouji Harada

Yukio Kawaguchi

Tamotsu Mizuguchi

Masami Hotta

Toshio Yamadera

An aspect of the present invention provides a wastewater treatment method for treating wastewater containing ammonium nitrogen, including the steps of: oxidizing the ammonium nitrogen in the wastewater to nitrite with nitrifying bacteria in a treatment tank in which the nitrifying bacteria and anaerobic ammonium-oxidizing bacteria having a half-saturation constant of 6.1 mgN/L or more with respect to nitrite coexist; and denitrifying the nitrite formed through the oxidation of the ammonium nitrogen, with the anaerobic ammonium-oxidizing bacteria in the treatment tank, while using the ammonium nitrogen contained in the wastewater as a hydrogen donor. The method employs the anaerobic ammonium-oxidizing bacteria that can maintain the denitrification activity even under a condition in which the amount of dissolved oxygen is large, consequently can easily maintain the activities of both of the nitrifying bacteria and the anaerobic ammonium-oxidizing bacteria which coexist in the same treatment tank, and can rapidly perform wastewater treatment.

Wastewater treatment method and wastewater treatment apparatus

A method for producing a nitrite type nitrification-reactive sludge includes the step of subjecting an activated sludge to alkali treatment so that the pH of the activated sludge containing at least the ammonium oxidizing bacteria and nitrite oxidizing bacteria can be 10 or higher, in order to accumulate ammonium oxidizing bacteria with higher priority in the activated sludge.

Waste water treatment apparatus

A nitrification carrier having made nitrifying bacteria dominant therein and a denitrification carrier having made anaerobic ammonium-oxidizing bacteria dominant therein are mixed in a treatment tank. Both of a nitrification reaction with the nitrification carrier and a denitrification reaction with denitrification carrier are allowed to proceed in the treatment tank to decompose ammonium nitrogen in wastewater to nitrogen gas. The ratio of the bacterial loads of the nitrifying bacteria and the anaerobic ammonium-oxidizing bacteria can be easily controlled by immobilizing the nitrifying bacteria and the anaerobic ammonium-oxidizing bacteria on different carriers from each other (nitrification carrier and denitrification carrier) and by controlling the volume ratio (ratio of the feeding amounts) of the nitrification carrier and the denitrification carrier.

A wastewater treatment method for treating wastewater containing ammonium nitrogen, includes the steps of: charging an unacclimated denitrification carrier containing anaerobic ammonium-oxidizing bacteria into a treatment tank; charging an unacclimated nitrification carrier containing nitrifying bacteria into the treatment tank; acclimating the unacclimated denitrification carrier in the treatment tank under an anaerobic condition; acclimating the unacclimated nitrification carrier in the treatment tank under an aerobic condition, after having acclimated the denitrification carrier; nitriting the ammonium nitrogen in the wastewater to generate nitrite with the acclimated nitrification carrier; and denitrifying the nitrite generated by nitriting the ammonium nitrogen with the acclimated denitrification carrier, while using the ammonium nitrogen in the wastewater as a hydrogen donor.

Wastewater treatment method

A large amount of entrapping immobilization pellets with highly stable quality are produced inexpensively by high-speed treatment. There is provided a process for producing entrapping immobilization pellets in which microorganisms are entrapped and immobilized in an immobilizing agent, the process comprising polymerizing a mixture containing the microorganisms and a solution of the immobilizing agent in a forming frame into a gel to prepare a pellet block.

Apparatus for producing pellets containing entrapped and immobilized microorganisms

The hydrogen-producing method of the an aspect of the present invention is a method for producing hydrogen in which hydrogen is produced from an organic matter using a microorganism, characterized by using pellets on which hydrogen-producing acid-resistant bacteria are entrapped and immobilized, producing hydrogen by bringing the pellets into contact and react with the organic matter in an environment of a pH of 4 to 6. The inventors of the present invention have obtained a finding that a hydrogen-producing bacteria are entrapped and immobilized, so that the optimum pH of the hydrogen-producing bacterium shifts to low range. The present invention is made based on the above finding and uses pellets on which the hydrogen-producing bacteria are entrapped and immobilized, so that the hydrogen-producing bacterium is activated at a low pH range of 4 to 6 to produce hydrogen. Therefore, the effects of contaminated bacteria that consume hydrogen are less, and the yield of hydrogen can be improved.

Method and apparatus for producing hydrogen and microorganism-immobilization pellets used in the same

It is possible to eliminate fluctuation in the pellet strength of the entrapping immobilization pellets according to production lots, and constantly and stably produce the entrapping immobilization pellets having high pellet strength regardless of the production lots. An apparatus for producing entrapping immobilization pellets by polymerizing an immobilizing material into a gel in the presence of an activated sludge to entrap and immobilize microorganisms in the immobilizing material, the apparatus including: a line mixer which mixes an activated sludge with an immobilizing material to prepare a raw material solution, a temperature sensor which measures a temperature of the prepared raw material solution, an addition pump which adds a polymerization initiator to the prepared raw material solution, and a controller which controls the addition pump according to the measured temperature to control an additive rate of the polymerization initiator.

Method for producing entrapping immobilization pellets, apparatus for producing the same, and entrapping immobilization pellets

The method for treating microcystin-containing water which detoxifies microcystin in the microcystin-containing water, the method comprises the step of: bringing the microcystin-containing water into contact with abacterium to degrade biologically the microcystin in the microcystin-containing water, wherein: thebacterium is a strain FERM P-19480 which is deposited as strain MDB1 with International Patent Organism Depositary, National Institute of Advanced Industrial Science and Technology.

[object Object]

Equipment for treating wastewater by anaerobic ammonium oxidation includes an anaerobic ammonium oxidation vessel to receive water to be treated containing ammonium and nitrite and to denitrify ammonium and nitrite in the water by anaerobic ammonium oxidizing bacteria, forming denitrified treated water, an acclimatization vessel downstream from the anaerobic ammonium oxidation vessel to receive the denitrified treated water from the anaerobic ammonium oxidation vessel, the acclimization vessel containing an immobilizing material that collects the anaerobic ammonium oxidizing bacteria in the denitrified treated water as immobilized microorganisms attached to the immobilizing material, wherein the acclimatization vessel has a structure such that the immobilizing material is prevented from flowing out of the acclimatization vessel, and a pipe connecting the acclimatization vessel to the anaerobic ammonium oxidation vessel.

Equipment for wastewater treatment comprising anaerobic ammonium oxidation vessel and acclimatization vessel

Process for producing pellets entrapping and immobilizing microorganisms

The present invention can feed substrates without waste to generate seed sludge with high bacterial cell concentrations and can start up operation within a short time, in cultivating anaerobic ammonium oxidizing bacteria with ammonium and nitrite as substrates. Equipment for cultivating anaerobic ammonium-oxidizing bacteria, which cultivates, in a cultivation tank, novel anaerobic ammonium-oxidizing bacteria that anaerobically denitrify nitrite and ammonium used as substrates, comprises an ammonium feed device which feeds ammonium at a given concentration into the cultivation tank, a nitrite feed device which feeds nitrite at a given concentration into the cultivation tank, and a control device which controls a feed rate Y of the substrate.

Method and equipment for cultivating anaerobic ammonium-oxidizing bacteria

A method for collecting bacterial cells includes feeding water containing ammonium and nitrite to an anaerobic ammonium oxidation vessel to denitrify ammonium and nitrite by anaerobic ammonium oxidizing bacteria provided in the anaerobic ammonium oxidation vessel to form denitrified water containing an amount of the anaerobic ammonium oxidizing bacteria and a sludge containing an amount of the anaerobic ammonium oxidizing bacteria; and feeding the denitrified water containing an amount of the anaerobic ammonium oxidizing bacteria and the sludge containing an amount of the anaerobic ammonium oxidizing bacteria to a precipitation vessel, in which an acclimatization container is stored, to cause the anaerobic ammonium oxidizing bacteria in the denitrified water to be attached to an immobilizing material in the acclimatization container, so that the anaerobic ammonium oxidizing bacteria in the denitrified water are collected, and, at the same time, to collect the anaerobic ammonium oxidizing bacteria of the sludge in a separated sludge by solid-liquid separation in the precipitation vessel.

Method and apparatus for collecting and acclimatizing anaerobic ammonium oxidizing bacteria, and denitrifying water

Entrapping immobilization pellets in which microorganisms are entrapped and immobilized, the entrapping immobilization pellets comprising entrapped and immobilized purified water sludge containing nitrifying bacteria.

Pellets comprising sludge containing nitrifying bacteria for treating wastewater

A process for storing entrapping immobilization pellets in which microorganisms are entrapped and immobilized in an immobilizing material until the entrapping immobilization pellets are used in a treatment tank, the process comprising:

Process for producing pellets containing entrapped microorganisms

Provided are a nitrite-type nitrification carrier and a method for producing the same and a method and an apparatus for removing nitrogen using the same, in which the quantity of organic matter to be added can be substantially reduced to reduce running cost. A method for producing a nitrite-type nitrification carrier in which ammonia-oxidizing bacteria for nitrifying ammonium to nitrite is preferentially accumulated comprises the steps of: entrapping and immobilizing any sludge selected from sediment from a lake, a river or the sea, soil from the surface of the earth, or activated sludge from a sewage-treatment plant into a monomer or a prepolymer for immobilizing microorganisms; and then subjecting the entrapped and immobilized sludge to heat treatment at 30 to 80&#xb0; C.

Nitrogen removing apparatus comprising nitrification carrier containing ammonia-oxidizing bacteria

Growing community of inventors

Tokyo, Japan

Tatsuo Sumino