Kurashiki Boseki Kabushiki Kaisha

Tokyo Shibaura Electric Co., Ltd.

Ryoji Muraki

Masao Endo

Nobuaki Aoki

Shinichiro Takemura

Tetsuo Ai

Athushi Ichioka

Masahiro Takeshita

Seiiti Numata

Takaaki Kawasaki

Kazuo Mizutani

Kanji Hayashi

Norio Fukui

Yoshio Ohashi

Estimated fuel flow rate is calculated by reading first data of the relationship between the opening degree of a fuel control valve and a fuel flow rate. Then, a compensation coefficient is calculated based on the estimated fuel flow rate, and the actual fuel flow rate is controlled on the basis of the compensation coefficient. Estimated excess air ratio is calculated by reading second data representing the relationship between the opening rate of an air control damper and the air flow rate. Then, the actual fuel flow rate and the air flow rate are controlled depending on the predetermined relationship of values between the estimated excess air ratio and the desired excess air ratio.

Fuel combustion control system

Nitrogen oxide contained in the flue-gas from a heating unit is removed in a nitrogen oxide removal unit by injection of nitrogen oxide removing agent in an amount determined by the amount of the nitrogen oxide contained in the flue-gas. Such amount of nitrogen oxide contained in the flue-gas is detected, on the one hand, by the estimation obtained through calculation using factors such as rate of supply of fuel to the heating unit and concentration of oxygen in the flue-gas, and on the other hand, by direct measurement, for a fail-safe system.

Input control method and means for nitrogen oxide removal

Method and apparatus for control of input to an apparatus for removal of nitrogen oxides from flue-gas by injection of a nitrogen oxide reducing agent according to which the level of nitrogen oxide concentration in the flue-gas can be selectively determined in reference to different factors relating to a combustion process, a first value indicating the amount of nitrogen oxide reducing agent to be injected is calculated on the basis of the determined level of nitrogen oxide concentration, and this first value is modified in accordance with nitrogen oxide removal efficiency actually achieved, and the rate of supply of the nitrogen oxide reducing agent is adjusted in accordance with the modified value obtained, whereby more precise and reliable input control is achieved.

Input control method and means for nitrogen oxide removal means

Apparatus for treating exhaust gases comprising a catalyst bed through which the exhaust gas is passed whereby nitrogen oxides and dust present therein are removed from the gas, said catalyst bed being designed such that the catalyst therein is discharged from the bed continuously or intermittantly while being fed in an amount that can compensate for the discharged amount, a heating device for heating the catalyst discharged from the bed to a temperature in a range from about 700.degree. to 1200.degree. C. for reactivation of the catalyst and separation of the dust accumulated on the bed surface and retained in the interstices between the catalyst particles therein, and a device for discharging sulfur dioxides produced during the course of heating the catalyst. This apparatus is very effective in simultaneously removing the nitrogen oxides and the dust from exhaust gases such as boiler exhaust gases.

Method for treating exhaust gases

A method for removing sulfur dioxide from waste gases by a wet oxidation-absorption method, which is characterized in that an aqueous solution of ammonium sulfate acidified with sulfuric acid at a pH range of 3 - 4 is used as the absorbent. The SO.sub.2 contained in the waste gases is absorbed with the aqueous solution of ammonium sulfate in an absorption tower and then oxidized with air or oxygen to be converted into sulfuric acid in an oxidation tower.

Method for removing sulfur dioxide from waste gases

Growing community of inventors

Nishinomiya, Japan

Ryoji Muraki