Hitachi, Ltd.

Babcock-hitachi Kabushiki Kaisha

Babcock-hitachi Kabushiki

Tooru Inada

Kiyoshi Narato

Shigeru Azuhata

Norio Arashi

Hironobu Kobayashi

Kenichi Sohma

Hiroshi Miyadera

Keizou Ohtsuka

Michio Kuroda

Yoji Ishibashi

Tadayoshi Murakami

Yasuo Yoshii

Yukio Hishinuma

Yoshitaka Takahashi

Tomohiko Miyamoto

Nobuyuki Hokari

Jinichi Tomuro

Tadahisa Masai

Katsuya Oki

Stephen M Masutani

Yasuo Iwai

Masayuki Taniguchi

Takashi Watanabe

Kazutoshi Higashiyama

Kenichi Souma

Hideo Kikuchi

Fumio Koda

Masao Masutani

Ken-ichi Sohma

Masakiyo Tanikawa

Kei Kawano

The present invention provides a method and an apparatus for predicting and calculating an amount of harmful oxide such as NOx contained in an exhaust gas from a reference concentration of harmful oxide, which is previously determined by a type of fuel supplied to a fluidized bed combustor, an amount of change of an air ratio and an amount of change of a gas residence time to the conditions of a specific air ratio and gas residence time in the combustor, and injecting a treatment agent such as NH.sub.3 in an amount optimum to the predicted amount into an exhaust gas. With this arrangement, an amount of harmful oxide in the exhaust gas can be securely lowered to a target value.

Method of predicting and controlling harmful oxide and apparatus therefor

A method of and apparatus for detecting an abnormality of a fluidized bed boiler is characterized in that an abnormality of the fluidized bed boiler is detected on the basis of a physical quantity related to a condition change of a gas existing in a space defined by a pressure vessel and the fluidized bed boiler accommodated within the pressure vessel.

Method of and apparatus for abnormality detection of a fluidized bed

A gas turbine combustor of the pre-mixed combustion system in which the pre-mixed fuel and the air are combusted. The gas turbine combustor comprises main cylindrical nozzles provided in the end wall on the upstream side of a cylindrical combustion chamber, auxiliary nozzles formed to surround the main nozzles, a main pre-mixed gas supply for supplying a pre-mixed gas to the main nozzles, and an auxiliary pre-mixed gas supply for supplying a pre-mixed gas having an fuel/air ratio smaller than that of the main pre-mixed gas to the auxiliary nozzles, and wherein it is allowed to stably burn a lean pre-mixed gas having an fuel/air ratio of greater than 1 from a low-load condition through and up to a high-load condition of the gas turbine.

Gas turbine combustor of the completely premixed combustion type

A gas turbine combustor comprises a combustion chamber, a premixing chamber in which hydrocarbon fuel and air are premixed, a nozzle with swirler for swirling and injecting the premixed fuel and air into the combustion chamber, to effect premixed combustion, and a fuel nozzle projecting into the combustion chamber and adapted to inject fuel at region wherein the premixed combustion is completed, so as to effect low air-ratio diffusion combustion thereby to produce reducing substance. NOx produced by the premixed combustion is reduced by reducing reaction with the reducing substances, so that the NOx concentration in the combustion gas is reduced. The combustor further includes an after-air ports on a peripheral wall defining the combustion chamber to effect combustion of unburnt substances.

Gas turbine combustor and a method of combustion thereby

A low NOx burning method and apparatus wherein a low air ratio flame burned with an amount of air less than an amount of air in a theoretical air ratio required for burning fuel perfectly is formed, and combustibles discharged from the low air ratio flame are burned at a trailing stream of the low air ratio flame while supplying air. The low air ratio flame is a premixing flame burned by premixing the fuel and air, and combustion of the premixing flames is maintained in the vicinity of the premixing flame. In this way, the generation of the NOx during the burning can be greatly decreased, and the required apparatus can be small-sized.

Low NOx burning method and low NOx burner apparatus

A spectroscope apparatus includes a device for separating light from an object to be measured into spectral components, a device for mixing spectral components which exists in a desired wavelength range, and a device for forming an image of the to-be-measured body of mixed light. The image obtained is very useful for observing the state of a combustion flame, the progress a photochemical reaction, the progress of a biochemical reaction, tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion by flame spectrophotometry. The apparatus provides accurate analytical information and makes possible precise control operations.

Spectroscope apparatus and reaction apparatus using the same

A low NOx burner comprises a pulverized coal nozzle for injecting a flow of a mixture of pulverized coal with primary air, a secondary air nozzle arranged externally of and coaxially with the pulverized coal nozzle, a tertiary air nozzle arranged externally of the secondary air nozzle and disposed coaxially with the pulverized coal nozzle, and a swirl flow generator for injecting secondary air and tertiary air as a respective swirl flow. Between the secondary air nozzle and the tertiary air nozzle, there is provided a spacer having such a thickness as to delay the mixing of the secondary air and the tertiary air and to form a swirl flow between the secondary air and the tertiary air.

Low NOx burner

A spectroscope apparatus includes means for separating light from an object to be measured into spectral components, means for mixing that part of the spectral components which exists in a desired wavelength range, and means for forming an image of the to-be-measured body of mixed light. The image thus obtained is very useful for observing the state of a combustion flame, the progress of photochemical reaction, the progress of biochemical reaction, a desired tissue in a cell, and the state of a flame for analyzing a solution which contains a metal ion, by flame spectrophotometery, that is, provides accurate information and makes possible a precise control operation.

An atomizer including a fuel supply passage for supplying a fuel, an atomizing medium supply passage for supplying an atomizing medium which is to be mixed with the fuel, a mixing chamber in communication with the fuel supply passage and the atomizing medium supply passage, and spray ports for spraying the fluid mixture consisting of the fuel and the atomizing medium from the mixing chamber. The fuel supply passage and the atomizing medium supply passages are communicated with the mixing chamber through a pre-mixing chamber having an annular cross-section defined by a large-diameter cylindrical surface and a small-diameter cylindrical surface. The fuel and the atomizing medium supplied from the fuel supply passage and the atomizing medium supply passage are pre-mixed the pre-mixing chamber. With this arrangement, it is possible to efficiently mix a slurry fuel and an atomizing medium, thus reducing the particle size of the atomized fuel particles and shortening the flame length. Thus, the atomizer of the invention is indispensable for the boilers which are intended for burning coal-water slurry. The invention makes it possible to form flames with reduced NOx generation and a high burning efficiency through combination between atomizer of the construction described above and a burner having a specific construction.

Atomizer and coal-water slurry fired boiler utilizing the same

A method of combusting a coal-water mixture fuel. The mixture is atomized into a conically-shaped primary pre-combustion chamber. Primary air is supplied, at a rate smaller than that required for complete burning of the mixture and in the form of a swirl about the axis of the jet of the atomized mixture, from the peripheral portion of the primary pre-combustion chamber into a secondary pre-combustion chamber connected to said primary pre-combustion chamber, thus forming a region of low pressure around the jet of the mixture. The region of low pressure serves to induce the atmosphere gas from the secondary pre-combustion chamber of higher temperature back into the primary pre-combustion chamber of a lower temperature, so that the water content of the mixture is evaporated and the mixture is ignited by the heat of the hot atmosphere gas. Then, the mixture is burnt in the secondary pre-combustion chamber in the presence of the remainder portion of the primary air, at a comparatively small air-to-ratio, so that a region of a reducing atmosphere is formed to suppress the generation of NOx. Then, secondary air is supplied, in the form of a swirl about the axis of the jet of the mixture and at a rate sufficient to completely burn the mixture, into the furnace connected to the secondary pre-combustion chamber, thus completely combusting the coal-water mixture.

Method of and apparatus for combusting coal-water mixture

A furnace system connected to a burner including a furnace for burning a fuel and air ejected from the burner into the furnace to produce a flame therein, and a combustion condition determining device for determining the conditions of combustion of the fuel in a zone of the flame extending along different strata thereof by collecting light in the flame at one point in the flame by moving such point. Signals outputted by the combustion condition determining device are utilized for monitoring or controlling the flame and controlling exhaust emission control devices for controlling exhaust emissions produced by the combustion of the fuel. Control of the conditions of combustion of the flame can be effected quickly with a high degree of precision by monitoring the flame.

Furnace system

There are the primary fuel nozzle for jetting the first coal in the fine powder form with an air ratio up to 1, and the secondary fuel nozzle for jetting the second coal in the fine powder form with an air ratio at least 1 from the outer circumferential portion of the primary fuel nozzle. Swirl means are located at the top of the secondary fuel nozzle for swirling the second coal.

Fuel jet method and apparatus for pulverized coal burner

A monitoring system for checking an electric rotary machine for local overheating including a sensing device for sensing the concentration of minuscule particles in a gas serving as coolant for the machine, and a supply device for supplying to the sensing device a test gas containing minuscule particles of gasifiable liquid. The test gas is supplied to the sensing device by the supply device to permit the sensing device to perform a sensing operation, so as to determine whether or not the sensing device is functioning normally.

Growing community of inventors

Hitachi, Japan

Tooru Inada