Abstract: The invention provides a NOx removal system for use in a boiler for realizing further reduction in NOx. Loading means for loading a reducing agent is provided at the outlet of a gas passageway in the boiler body, and a NOx removal catalyst is provided downstream of the loading means.

Abstract: A NOx removal system for boilers in which the need for any special heat retainer or any warming mechanism is eliminated. Ammonia jet nozzles are disposed on a gas passage of a boiler or flue, and an ammonia generator connected to the jet nozzles is disposed within the flue.

Abstract: The invention provides a NOx removal system for use in a boiler for realizing further reduction in NOx. Loading means for loading a reducing agent is provided at the outlet of a gas passageway in the boiler body, and a NOx removal catalyst is provided downstream of the loading means.

Abstract: A NOx removal system for boilers in which the need for any special heat retention means or any warming means is eliminated. Ammonia jet nozzles are disposed on a gas passage of a boiler or flue, and ammonia generating means connected to the jet nozzles is disposed within the flue.

Abstract: Combustion method and apparatus for NOx reduction and CO reduction which are capable of easily achieving super NOx reduction with the value of exhaust NOx under 10 ppm. The combustion method for NOx reduction by controlling the temperature of combustion gas derived from a burner includes in combination the steps of suppressing combustion gas temperature by heat absorbers; suppressing the combustion gas temperature by recirculating burning-completed gas to a combustion-gas burning reaction zone; and suppressing the combustion gas temperature by adding water or steam to combustion-use air of the burner, whereby the temperature of the combustion gas derived from the burner is suppressed.

Abstract: Combustion method and apparatus for NOx reduction are capable of easily achieving NOx reduction to an exhaust NOx value of 30 ppm or under. The combustion method is to perform in combination a first NOx reduction step for suppressing generated NOx value to 60 ppm or under (at 0% O2 in exhaust gas, dry basis) by a low NOx burner, a second NOx reduction step for recirculating exhaust gas of the low NOx burner to a burning reaction zone formed by the low NOx burner, and a third NOx reduction step for adding water or steam to the burning reaction zone.

Abstract: Combustion method and apparatus for NOx reduction which are capable of achieving NOx reduction with the value of exhaust NOx under 10 ppm, as well as CO reduction at the same time. The combustion method for fulfilling NOx reduction and CO reduction by suppressing temperature of combustion gas derived from a burner comprises a NOx reduction step for suppressing combustion gas temperature in such a manner that suppression of NOx generation is preferred to reduction of exhaust CO value, thereby keeping NOx value not more than a specified value, and a CO reduction step for thereafter reducing exhaust CO value resulting from the NOx reduction step to not more than a specified value.

Abstract: Combustion method and apparatus for NOx reduction are capable of easily achieving NOx reduction to an exhaust NOx value of 30 ppm or under. The combustion method is to perform in combination a first NOx reduction step for suppressing generated NOx value to 60 ppm or under (at 0% O2 in exhaust gas, dry basis) by a low NOx burner, a second NOx reduction step for recirculating exhaust gas of the low NOx burner to a burning reaction zone formed by the low NOx burner, and a third NOx reduction step for adding water or steam to the burning reaction zone.

Abstract: Combustion method and apparatus for NOx reduction and CO reduction which are capable of easily achieving super NOx reduction with the value of exhaust NOx under 10 ppm. The combustion method for NOx reduction by controlling the temperature of combustion gas derived from a burner includes in combination the steps of suppressing combustion gas temperature by heat absorbers; suppressing the combustion gas temperature by recirculating burning-completed gas to a combustion-gas burning reaction zone; and suppressing the combustion gas temperature by adding water or steam to combustion-use air of the burner, whereby the temperature of the combustion gas derived from the burner is suppressed.

Abstract: Combustion method and apparatus for NOx reduction which are capable of achieving NOx reduction with the value of exhaust NOx under 10 ppm, as well as CO reduction at the same time. The combustion method for fulfilling NOx reduction and CO reduction by suppressing temperature of combustion gas derived from a burner comprises a NOx reduction step for suppressing combustion gas temperature in such a manner that suppression of NOx generation is preferred to reduction of exhaust CO value, thereby keeping NOx value not more than a specified value, and a CO reduction step for thereafter reducing exhaust CO value resulting from the NOx reduction step to not more than a specified value.

Abstract: A method for controlling a NOx removal system in which reductant supply is adjusted according to combustion level in a boiler (1) in which the combustion level is controlled in multiple stages. For a decrease of the combustion level, the reductant supply is kept lower than a level corresponding to a changeover-target combustion level for a period of a set time from the changeover of the combustion level. Thus, when the reductant supply is changed over in response to a changeover of combustion level, the reductant can be prevented from flowing outside as it is unreacted.

Abstract: A NOx removal system for boilers in which the need for any special heat retention means or any warming means is eliminated. Ammonia jet nozzles 7 are disposed on a gas passage (5) of a boiler (1) or flue (6), and ammonia generating means (8) connected to the jet nozzles (7) is disposed within the flue (6).

Abstract: The invention provides a water-tube boiler which allows further NOx reduction and CO reduction with a simple construction of the boiler body and the burner itself. The water-tube boiler includes a first water tube array made up of a plurality of first water tubes arranged into an annular shape, a combustion chamber defined inside the first water tube array, a first opening defined at part of the first water tube array, a cooling water tube array made up of a plurality of cooling water tubes arranged into an annular shape in a zone within the combustion chamber where burning-reaction ongoing gas is present, gaps provided between adjacent cooling water tubes so as to permit the burning-reaction ongoing gas to flow through, and a burning-reaction continuing zone, where burning reaction is continuously effected, provided between the cooling water tube array and the first water tube array, whereby the burning-reaction ongoing gas generally uniformly contacts the individual cooling water tubes.

Abstract: A method for controlling a NOx removal system in which reductant supply is adjusted according to combustion level in a boiler (1) in which the combustion level is controlled in multiple stages. For a decrease of the combustion level, the reductant supply is kept lower than a level corresponding to a changeover-target combustion level for a period of a set time from the changeover of the combustion level. Thus, when the reductant supply is changed over in response to a changeover of combustion level, the reductant can be prevented from flowing outside as it is unreacted.

Abstract: The invention provides a NOx removal system for use in a boiler for realizing further reduction in NOx. Loading means for loading a reducing agent is provided at the outlet of a gas passageway in the boiler body, and a NOx removal catalyst is provided downstream of the loading means.

Abstract: The invention provides an ammonia generating apparatus which is high in efficiency of heat transfer and compact. The ammonia generating apparatus includes a urea water introducing part, a flow passage for urea water to flow therethrough, and heating means, wherein the flow passage is connected to the urea water introducing part, and the heating means heats urea water present within the flow passage.

Abstract: A water-tube boiler which allows further NOx reduction and CO reduction to be implemented with an uncomplicated construction of the boiler body itself, and which is improved in boiler efficiency. The water-tube boiler includes a first water tube array made up of a plurality of first water tubes arranged into an annular shape and a combustion chamber inside the first water tube array.

Abstract: In a water-tube boiler in which pollutant (especially NOx) emissions are reduced, a plurality of water tubes arranged in an annular shape are provided. At least some of the water tubes thereof are spaced apart along an annulus so as to provide a plurality of gaps therebetween. A combustion-reaction ongoing gas passes through these gaps, and a temperature thereof is lowered to 1400.degree. C. upon contact with the water tubes. The boiler further includes a second plurality of water tubes arranged in an annular shape outside of the first plurality of water tubes. By adjusting the arrangement of the water tubes along respective annuli and/or adjusting an orientation of the tubes along their length (so as to be straight, tilted, or bent), control of the exhaust emissions is enhanced.

Abstract: The invention provides a water-tube boiler and a burner capable of realizing a reduction in NO.sub.x and CO in both the combustion of liquid fuel and the combustion of gaseous fuel. The water-tube boiler comprises a burner which uses liquid fuel or gaseous fuel switchably, characterized in that a plurality of water tubes are arranged into an annular shape in a zone where burning-reaction ongoing gas derived from the burner is present within a combustion chamber. The water-tube boiler comprises a burner which uses either liquid fuel or gaseous fuel. A first water tube array is formed by arranging a plurality of water tubes into an annular shape in a zone where burning-reaction ongoing gas derived from the burner is present within a combustion chamber. Gaps are provided between adjacent water tubes of the first ongoing gas to flow therethrough. A zone is provided around the first water tube array to allow burning reaction to be continuously effected.

Abstract: The water-tube boiler fulfills the reduction in NO.sub.x with a simple constitution, and achieves reduction in NO.sub.x and reduction in CO at the same time with a simple constitution. In the water-tube boiler, a plurality of water tubes (5) are arranged in a zone where burning-reaction ongoing gas derived from a burner (10) is present within a combustion chamber (9), and exhaust gas recirculation equipment (26) is provided to feed part of exhaust gas exhausted from the combustion chamber 9 to the burner 10.