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: A water softening device and a method for regeneration control thereof, in which the hardness of feedwater to be softened is detected with the lapse of time and regeneration timing is controlled based on the detected value. The invention includes an inlet hardness measurement device for measuring the hardness of feedwater to a water softener, treated water quantity measurement device for measuring a flow rate of treated water after passing through the water softener, brine concentration detection device for detecting the concentration of brine in regeneration operation, and brine consumption detection device for detecting tile consumption of brine in regenerating operation. Further, there are included hardness leakage detecting device for measuring the hardness of treated water after passing through the water softener and detecting hardness leakage.

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 hardness indicator composition, and a method of water hardness analysis, capable of measuring hardness even with higher-hardness water without requiring titration by a two-liquid system. The hardness indicator composition is formulated of a metal indicator with a desensitizer added thereto.

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: Boiler efficiency is further improved and the whole boiler body is slimmed down by totally improving heat transfer surfaces confronting gas flow passages, i.e., by forming the heat transfer surface structure into three stages, and moreover by making effective use of the whole heat transfer surfaces of water tubes equipped with fully circumferentially finned water tubes.

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: A harness indicator is highly reactive to a trace amount of Ca2+, and is slow to degrade in a high temperature environment of greater than 50° C. In one embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of Mg-EDTA. In another embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of anhydrous Mg-EDTA. In another embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of anhydrous Mg-EDTA and potassium sorbate. In a further embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of Mg-EDTA and potassium sorbate. In a further embodiment, the hardness indicator contains EBT, a pH buffer, and a masking agent as main components, and an admixture of potassium sorbate.

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 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.

Abstract: A liquid feeding apparatus quantitatively feeds a liquid by pressing and clogging an elastic tube between a press roller and an arc-shaped guide portion through rotational motion of the press roller. The liquid feeding apparatus includes a main unit in which the press roller is provided, and a liquid cassette which accommodates a liquid cartridge. One end of the elastic tube is connected to a reservoir for the liquid to be fed, and the other end is connected to a check valve. The liquid cassette is removably fitted to the liquid feeding apparatus so that the elastic tube is subject to pressing action of the press roller.

Abstract: The membrane deaerator according to the present invention includes a plurality of membrane deaerator modules and a water sealed vacuum pump connected thereto. These modules are series-connected between a raw water supply line and a deaeration water supply line. A first vacuum pump is connected to a first deaerator module via a deaeration line, and a second vacuum pump is connected to a second deaerator module via the deaeration line. These vacuum pumps are each provided with a seal water supply line which is used to send the raw water introduced from the water supply line thereinto as seal water to each of the first and second vacuum pumps. A discharge line for the second vacuum pump is connected to the deaeration line for the first vacuum pump. In the membrane deaerator thus formed, the deaeration performance is improved greatly, and a deaeration with dissolved oxygen concentration of several PPB can be carried out.