Abstract: A method for minimizing corrosion and the build-up of deposits on surfaces of a flue-gas system exposed to moist substances and elevated temperatures, and particularly those surfaces which are used to convey other additives to the system and the surfaces of gas/gas heaters which receive the output from scrubbers, which method involves adding to the system, particularly in those conduits and at the surfaces of the gas/gas heater, generally inert bulking agents such as perlite and vermiculite in expanded form, such agents, apparently by acting under the operating conditions to which they are subjected to retain substantial quantities of water without becoming dissolved, accomplishing the desired results.

Abstract: A method for minimizing corrosion and the build-up of deposits on surfaces of a flue-gas system exposed to moist substances and elevated temperatures, and which includes a desulfurizer and heat transfer means communicating with the desulfurizer, said method involving adding to the system at the heat transfer means a readily water soluble alkaline substance such as sodium hydroxide in amounts sufficient to produce with said flue-gas in said heat transfer means a minimum pH of about 5, preferably 7 or higher.

Abstract: A method for minimizing corrosion and the build-up of deposits on surfaces of a flue-gas system exposed to moist substances and elevated temperatures, and particularly those surfaces which are used to convey other additives to the system and the surfaces of gas/gas heaters which receive the output from scrubbers, which method involves adding to the system, particularly in those conduits and at the surfaces of the gas/gas heater, generally inert bulking agents such as perlite and vermiculite in expanded form, such agents, apparently by acting under the operating conditions to which they are subjected to retain substantial quantities of water without becoming dissolved, accomplishing the desired results.

Abstract: Boiler fouling, particularly in air preheater section, is minimized by combining with a substance designed to neutralize acids a detergent builder such as the sodium, potassium and ammonium phosphates, polyphosphates, silicates, metasilicates, borates, metaborates and sesquicarbonates.

Abstract: By adding a specific blend of coarse and fine particles of a magnesium compound to a relatively low temperature zone of a furnace system noxious and undesirable emissions are greatly reduced and internal boiler conditions are greatly improved.

Abstract: By providing a combination of manganese and magnesium to the combustion area, where the amounts of the two substances are within certain limits, noxious and undesirable emissions are greatly reduced, internal boiler conditions are greatly improved, and lesser amounts of cold end additives need be employed to obtain still greater improvements.

Abstract: The method of operation of a boiler system to which an additive is to be fed at a controlled rate and in which the optimal additive rate depends upon a plurality of changing parameters of the boiler system, in which the relationship between each of those parameters and the optimal additive feed rate is determined, the relevant parameters are sensed during the operation of the system, their effects on optimum additive feed are computed in accordance with said relationships and combined on a continuous basis to produce a control signal representative of the desired rate of additive feed, and controlling the additive feed in accordance therewith, all preferably continuously.

Abstract: The collection characteristics of particles entrained in a particle-laden gas for collection by an electrostatic precipitator are improved by injecting finely divided sodium and ammonium phosphate salts into a particle-laden gas stream formed by the burning of coal. Sufficient additive is injected to provide 24-1200 grams per metric ton of coal burned to form the gas. After injection, the stream is directed through a heat exchange means and finally into the precipitator to collect the particles therein.

Abstract: The separation characteristics of particles entrained in a particle-laden gas for separation by the commonly used methods for removing particles from a gas stream are improved by injecting finely divided urea into the gas stream prior to its passage through the separator. The urea conditioner agglomerates the particles to facilitate their removal from the gas stream by the separator.

Abstract: The fusion point of coal ash in a boiler is reduced by introducing a boron-containing compound into a boiler containing coal ash and mixing the compound and the coal ash. Preferably the compound is introduced into the furnace box of the boiler as an intimate mixture of pulverized or crushed coal and the compound, the coal being intimately mixed with the compound prior to introduction of the mixture into the furnace box.

Abstract: The collection characteristics of particles entrained in a particle-laden gas for collection by an electrostatic precipitator are improved by injecting finely divided ammonium bisulfate into a particle-laden gas stream formed by the burning of coal while the gas has a temperature of 590-900.degree. C. Sufficient ammonium bisulfate is injected to provide 75-1250 grams per metric ton of coal burned to form the gas. After injection, the stream is directed through a heat exchange means and finally into the precipitator to collect the particles therein.