coal fired boiler flue gas temperature dew point

Sulfuric Acid Dewpoint Temperature Monitor

In order to maintain the operating efficiency of coal or oil-fired boilers, it is important to know that the temperature of the exhaust gas is above the sulfuric acid dewpoint temperature (ADT). If it is much higher than the sulfuric acid dewpoint temperature, then energy is wasted heating the gas and efficiency drops.

Research article The economics of flue gas cooling technology

are described in this paper. In conventional pulverised coal-fired boilers, cooling of gas prior to the wet flue gas desulfurisation (WFGD) absorber reduces water consumption for evaporative cooling of the flue gas and can recover heat for feed water preheating or for use elsewhere in the plant.

For air and flue gas duct systems

flue gas with fly ash is decisive. In the “cold” area the expansion joint is affected by the formation of aggres - sive condensate, due to the temperature falling below the dew point. KE® Fabric Expansion Joints are installed in coal-fired power plants, including the coal mill inlet and outlet: • Coal dust lines • Secondary lines

Fuels Flue Gases and Average Dew Points

Combustion Efficiency and Excess Air - Optimizing boilers efficiency is important to minimize fuel consumption and unwanted excess to the environment; Combustion Testing - Combusting testing of fuel oil and gas burners; Flue Gas Dew Point Temperatures - Flue gas dew point temperatures and the condensation of water vapor

Eliminating Air Heater Plugging and Corrosion Caused by SCR

In a typical coal fired power plant, the rotary regenerative air heater is responsible for between 5 percent and 10 percent of the boiler’s total efficiency, thus making it a critical component

Institute of Combustion and Power Plant Technology

−Residence time of the flue gas between 700 and 800°C • SO 2 oxidation takes place: −In the boiler and economizer: depending on coal and boiler (in air firings: up to 1.6% of toal SO 2 converted) [3] −In the SCR-reactor (in air firings up to 1.25% of total SO 2 converted) [3] 4

Furnace Exit Gas Temperature Control (FEGT) Monitoring.

The fuel and air are mixed, combustion takes place in the burner system and the next monitoring point in the flue gas path is the boiler exit temperature. Basically, there is nothing in between. So introduce a third control point in between the burner and boiler exit temperature i.e., furnace exit gas temperature (FEGT).

Fuel Additives for Coal-Operated Boilers in Power Plants

Pre-Combustion injection of chemicals on the coal TECHNICAL ASPECT OF SENTROJET TREATMENT. SENTROJET is the form of an aqueous solution, injected on the coal belt or into the flue path of the boiler or furnace. If post-combustion, injection is done at a point where the flue temperature is greater than 500°C.

Fabric filters (baghouses) | IEA Clean Coal Centre

The choice between ESP and fabric filtration generally depends on coal type, plant size and boiler type and configuration. LOG IN OR REGISTER Fabric filters, which generally operate in the temperature range 120-180°C, have been more widely used since the 1970s, especially at industrial scale.

Coal-Fired Power Plant Heat Rate Reductions

The average, annual operating heat rate of U.S. coal-fired power plants is approximately 10,400 Btu/kWh. The design heat rate of a facility is based on full-load operation with no boiler blowdown, whereas most reported heat rates of operating facilities include performance during off-peak loads and include boiler blowdown.

Enhancing ESP Efficiency for High Resistivity Fly Ash by

0BAbstract: the resistivity of fly ash after coal-fired boilers varies with the flue gas temperature. the normal esp operating temperature of around 150 ℃ is typically near the maximum resistivity of the ash. for low sulphur coals the resistivity will sharply

Formation and Control of Sulfur Oxides in Boilers

Natural gas burned in boilers usually contains quite minor amounts of sulfur. Even though natural gas from some fields contains appreci-able amounts of H2S, this is commonly removed by the producer. As a general rule, 90% or more of the sulfur in the fuel will be found as sulfur oxides in the flue gas. Typically, the flue gas concentration of SO2 is of the

Research on formation mechanism of typical low-temperature

As known, the fouling layer and low temperature corrosion are mainly caused by H 2 SO 4 condensation in the coal-fired boiler , . Several field experiments have been carried out to figure out the formation mechanism of fouling layer outside heating surfaces in different location of the flue gas.

Challenges when Converting Coal-Fired Boilers to Natural Gas

Riley Power recently participated in field testing on a wall fired boiler rated at 1,779,000 lb/hr of main steam flow. The boiler is an opposed fired design with two (2) levels of burners on both the front and rear walls. The natural gas supply system to the boiler utilized a single flow control valve for all the burners.


Flue gas from coal-fired boilers also contains relatively high water vapor concentrations, resulting in water vapor dewpoint temperatures from 100 to 135°F, depending on coal moisture content. For those applications in which the flue gas temperature is reduced to temperatures below the water vapor dewpoint, the liquid mixture of water and sulfuric acid

Prediction of Acid Dew Point in Flue Gas of Boilers Burning

The higher SOx concentrations, particularly SO3 in combination with high concentration of water in the recycled flue gas, increase the sulphuric acid dew point temperature in oxy-fuel fired

ICRN 23 IAPWS Certified Research Need - ICRN

In summary, z For design of air preheaters for coal-fired boilers, there is a need for accurate data and/or formulations for dew point for a range of actual flue gas compositions, including the effect of fly ash and wall temperature distribution, in order to reduce and keep proper design margins.

Prediction of Acid Dew Point in Flue Gas of Boilers Burning

The temperature of flue gas should be controlled to be higher than the acid dew point to avoid fouling and corrosion of heating surfaces in the second pass of boilers. Decreasing the temperature of flue gas in boilers is one of the most effective ways to improve thermal efficiency, enhance electrostatic precipitator efficiency, and decrease water consumption of the desulfurization tower.

Absensor ADM – Breen Energy Solutions

Applications include, Fired Heater-APH inlet and outlet, FCCU-CO boiler SCR outlet and downstream gases, black liquor recovery boilers and other corrosive flue gas applications. Unlike traditional Acid Dew Point Meters, the AbSensor-ADM measures the dew point of combustion and process gases, independent of the condensable species (i.e. Dew

Boiler Flue-Gas Measurements Using a Dewpoint Meter | Journal

The context of this paper presents a review of those factors thus revealed by these investigations as major contributors to plugging and corrosion processes in air preheaters installed on oil-fired boilers. These tests disclosed that corrosion potential of boiler flue gases is directly effected by the degree of boiler slagging.

Dew Point of the Flue Gas of Boilers Co-Firing Biomass with Coal

The adiabatic dew point temperature of the flue gas is close to 65 °C. This is influenced by the moisture content of the flue gas [9] and the oxygen content of the exhaust gas [10]. In order to

Formation and Control of Sulfur Oxides in Boilers

in oil-fired boilers. However, experi-mental studies by Rendle and Wilsdon13 and by Taylor and Lewis14 failed to show an effect of the vanadium content of oils on the dew point of the flue gases. Anderson and Manlik15 carried out an extensive series of tests on an oil-fired experimental boiler. The amount of SO3 formed was determined indirectly


steam electric power plant was developed. The model included a conventional pulverized coal-fired boiler, an electrostatic precipitator for particulate removal, a wet limestone FGD system with optional flue gas bypass, an inline steam reheater, and a separate induced draft fan for each scrubbing train.

Scrubber - Wikipedia

The gas leaves the scrubber at its dew point, so even though significant amounts of water may have been removed from the cooled gas, it is likely to leave a visible stack plume of water vapor. Dry scrubbing. A dry or semi-dry scrubbing system, unlike the wet scrubber, does not saturate the flue gas stream that is being treated with moisture. In some cases no moisture is added, while in others only the amount of moisture that can be evaporated in the flue gas without condensing is added.

Typical 500 MW Coal Fired Plant

acid dew point, then it becomes an efficiency loss equal to about 1% in efficiency for every 35oF of corrected to no leakage temperature at the APH exit. An approximation of unit heat rate penalty for air in-leakage of up to 20% equivalent ambient air, is over 300 tu’s/kWh in heat rate penalty.

Calculation and analysis of acid dew-point temperature in

Coal-fired boiler, Gas, Acid dew-point temperature Abstract The current calculation method of the acid dew-point temperature of the flue gas is multifarious, and many formulas even exist obvious errors.

Sulfuric Acid Dewpoint Temperature Monitoring in combustion

Applications Fuel Oil Coal Diesel fuel oil Petcoke Oremulsion. The continuous sulfuric acid dewpoint monitor (Model 440) should be installed at a point where the SO 3 and the water have completely combined (98% or better). This is typically in locations where the flue gas temperature is below 205 °C / 400 °F

Technical advice on boiler combustion control

Stack loss generally ranges from as much as 30 percent for a green-wood-fired boiler, to 18 percent for a typical natural-gas-fired boiler, to 12 percent for an oil-fired boiler, to as low as 9 percent for a coal-fired boiler. It must be pointed out that the stack-loss range is wide for any given fuel.

Effects of Coal-Fired Boiler Flue Gas Conditioning on Fly Ash

Hopper heaters should be used but the temperature should be kept at around 30°F above the flue gas dew point. Higher heater temperatures can drive off crystalline water leaving solid bridges.

Dry flue gas cleaning, TurboSorp - ANDRITZ

Turbo CDS is the right choice for flue gas cleaning downstream of oil or coal-fired boilers. Our dry flue gas cleaning processes are based on well-proven circulating fluidized bed technology.

Fuel Additives for Coal-Operated Boilers in Power Plants

THE SENTRO TECHNOLOGIES SOLUTION. SENTROJET chemical will neutralize the sulfur trioxide in the flue gas by the continuous injection of a product containing a water-soluble magnesium compound and which will lower the sulfuric acid dew point temperature to any level required to avoid condensation and therefore corrosion. Any residue will be dry,


The temperature of the flue gas is a critical parameter that influences the ash accumulation. The exhaust flue gas temperature in practical coal-fired boilers varies in 115~130°C, about 20°C above the calculated acid dew point [19]. Since 3

Get acid dew point of flue gas (Journal Article) | OSTI.GOV

The dew point usually limits the practical lower temperature of the flue gas to 300 to 350/sup 0/F. If the temperature of the equipment in contact with the gas is below the dew point, moisture and acid, generally sulfurous or sulfuric acid, can condense and the exposed metal surface of the equipment deteriorates rapidly due to corrosion.

How Is The Low Temperature Corrosion of Boiler Caused

The dew point of flue gas is obviously increased by the presence of sulfuric acid vapor. For example, the pressure of water vapor in the flue gas of an oil fired boiler is about 0.008~0.014Mpa, and the corresponding thermodynamic dew point is 41~52℃.

Bag Filter for Boilers - Pollution Control Bag Filters

Pollution Control Bag Filter for Boilers Flue Gas. To control the emission of wood/coal/lignite fired Boilers it is necessary to have Bag Filter. This will limit the SPM level of the emission and if gases (sulphur) are also a constraint then one should go for venturi type wet scrubber in loop after bag filter.

Boiler Cold End Corrosion - Mechanism and Prevention methods

May 07, 2017 · The leakage of boiler tubes or excess steam used in steam assisted soot blower may lead to adding the moisture content. Also, it will alter the dew point of the exhaust flue gas. Increasing the moisture content in the flue gas cause increasing the dew point of the flue gas. ie., the dew point will rise to 150 o C from 120 o C. This will leads to severe cold end corrosion.

Corrosion in coal-fired boilers (Technical Report) | OSTI.GOV

@article{osti_5470434, title = {Corrosion in coal-fired boilers}, author = {Vausher, A.L.}, abstractNote = {The corrosive effect of the flue gas and the fly ash from burning coal on combustion and pollution control equipment has led to extensive research efforts aimed at solving this problem.

Prediction of Acid Dew Point in Flue Gas of Boilers Burning

Mar 08, 2016 · The temperature of flue gas should be controlled to be higher than the acid dew point to avoid fouling and corrosion of heating surfaces in the second pass of boilers. Decreasing the temperature of flue gas in boilers is one of the most effective ways to improve thermal efficiency, enhance electrostatic precipitator efficiency, and decrease water consumption of the desulfurization tower.

Flue Gas Dew Point Temperatures - Engineering ToolBox

Related Documents. Fuels Flue Gases and Average Dew Points - Flue gas dew point temperatures for typical fuels Optimal Combustion Process - Fuels and Excess Air - Stable and efficient combustion conditions require correct mixture of fuels and oxygen.

Chapter 22 - Coil-end Deposition and Corrosion Control | SUEZ

Consequently, dew points are raised. With any type of fuel, corrosion and fouling potentials rapidly increase below gas temperatures of 140 degrees F (60 degrees C), which is the typical water dew point for flue gases. Cold-end corrosion and deposition are usually much less severe in coal-fired boilers than in oil-fired units.

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