Fuel Oil Reburning Application for NOx Control to Firetube Package Boilers

1987 ◽  
Vol 109 (2) ◽  
pp. 207-214 ◽  
Author(s):  
J. A. Mulholland ◽  
R. E. Hall
Keyword(s):  
Natural Gas ◽  
Nitrogen Content ◽  
Nox Reduction ◽  
Pilot Scale ◽  
Fuel Oil ◽  
Limiting Factor ◽  
Boiler Load ◽  
Residual Fuel Oil ◽  
Nox Control ◽  
Percent Nitrogen

Two pilot-scale (0.73 MW or 2.5 × 106 Btu/hr) firetube package boilers were retrofitted for fuel oil reburning application for NOx emission control. When firing distillate fuel oil (0.01 percent nitrogen content), an overall NOx reduction of 46 percent from an uncontrolled emission of 125 ppm (dry, at zero percent O2) was realized by diverting 20 percent of the total boiler load to a second stage burner; a 51 percent NOx reduction from 265 ppm was achieved in a distillate/residual fuel oil mixture (0.14 percent nitrogen content) reburning application. Nitrogen-free fuel oil reburning was found to be slightly more effective at reducing NOx than was natural gas reburning, although longer fuel-rich zone residence times were required to allow for evaporation and mixing of the fuel oil droplets. Key parameters investigated which impact the reburning process were: primary flame NOx, reburn zone stoichiometry, and reburn zone residence time. Reburning applied to firetube package boilers requires minimal facility modification. Reburning can be coupled with other NOx control techniques (e.g., distributed air low NOx burners) to achieve NOx emissions of less than 100 ppm. However, for very low primary flame NOx conditions (i.e., less than 200 ppm), reburning fuel nitrogen content is a limiting factor, and reburning with a low-nitrogen-content fuel, such as natural gas or nitrogen-free distillate oil, may be necessary to achieve 50 percent NOx reduction.

Application of Reburning for NOx Control to a Firetube Package Boiler

1985 ◽  
Vol 107 (3) ◽  
pp. 739-743 ◽  
Author(s):  
J. A. Mulholland ◽  
W. S. Lanier
Keyword(s):  
Natural Gas ◽  
Reaction Order ◽  
Nox Reduction ◽  
Process Variable ◽  
Nox Emission ◽  
Boiler Load ◽  
Second Stage ◽  
Primary Zone ◽  
Dominant Process ◽  
Nox Control

A 730 kW (2.5 × 106 Btu/hr) firetube package boiler was used to demonstrate the application of reburning for NOx emission control. An overall reduction of 50 percent from an uncontrolled NOx emission of 200 ppm was realized by diverting 15 percent of the total boiler load to a natural-gas-fired second stage burner. Tests indicate that the overall reaction order of destruction with respect to initial NOx is greater than one; thus, larger reductions can be expected from reburning applications to systems with higher initial NOx. Rich zone stoichiometry has been identified as the dominant process variable. Primary zone stoichiometry and rich zone residence time are parameters that can be adjusted to maximize NOx reduction. Reburning applied to firetube package boilers requires minimal facility modification. Natural gas would appear to be an ideal reburning fuel as nitrogen in the reburning fuel has been shown to inhibit NOx reduction.

IGR Solid-State Electrochemical NOx Control for Natural Gas Combustion Exhaust Gases

1989 ◽  
Vol 111 (3) ◽  
pp. 394-397 ◽  
Author(s):  
M. S. Hossain ◽  
M. Neyman ◽  
W. J. Cook ◽  
A. Z. Gordon
Keyword(s):  
Solid State ◽  
Natural Gas ◽  
High Surface ◽  
Nox Reduction ◽  
High Surface Area ◽  
Combustion Products ◽  
Gas Combustion ◽  
Electrochemical Technology ◽  
Natural Gas Combustion ◽  
Nox Control

Solid-state electrochemical technology, embodied in the IGR process, is used to reduce nitrogen oxides (NOx) to nitrogen and oxygen, and thereby control NOx emissions from natural gas powered engines. The IGR deNOx process is based on solid-state, flow-through, high surface area, porous oxygen ion conductive ceramic electrolytes. Recent bench-scale experiments conducted for the Gas Research Institute have demonstrated NOx reduction in multicomponent gas streams, the inert portion of which simulate natural gas combustion products. The reduction products were analyzed by in situ gas chromatography to verify NOx reduction rates inferred from electrochemical measurements. IGR process advantages compared with existing NOx control technologies are reviewed.

Natural Gas Markets in Asia: From Callow Youth to Maturity

1992 ◽  
Vol 10 (2) ◽  
pp. 131-140
Author(s):  
Donald I. Hertzmark
Keyword(s):  
Natural Gas ◽  
Southeast Asia ◽  
Energy Use ◽  
Oil Production ◽  
Gas Production ◽  
Fuel Oil ◽  
Leading Role ◽  
Residual Fuel Oil ◽  
Oil Markets

In the 1980s, Asian energy markets expanded at a rapid rate to meet the surge in demand from Japan, Korea, and Taiwan. This demand boom coincided with an increase in non-OPEC oil production in the region. As oil production stabilizes, demand looks set to rise sharply, this time in the new Newly Industrialized Countries of Southeast Asia, Thailand, Malaysia, and Indonesia. Natural gas will play a key role in this expansion of energy use and could start to lead rather than follow oil markets. The leading role of natural gas will be especially strong if gas starts to make inroads in the high and middle ends of the barrel with oxygenated gasoline and compressed natural gas for trucks. At the bottom of the barrel, natural gas could increasingly usurp the role of residual fuel oil for environmental reasons. At the same time, regional refiners could find that residual oil is their leading source of additional feed for the new process units currently under discussion or planning. The supply outlook for natural gas is increasingly fraught with uncertainties as more of the region's supplies must come from distant areas. In particular, LNG supplies from Malaysia and Indonesia will need to be replaced by the early part of the next century as rising domestic demand eats into the exportable gas production. New sources include China, Siberia, Sakhalin Island, Papua New Guinea, and Canada. There will be intense competition to supply the Northeast Asian markets as the gas production in Southeast Asia is increasingly used within ASEAN.

Experimental Study of NOx Formation in Lean, Premixed, Prevaporized Combustion of Fuel Oils at Elevated Pressures

2007 ◽  
Author(s):  
P. Gokulakrishnan ◽  
M. J. Ramotowski ◽  
G. Gaines ◽  
C. Fuller ◽  
R. Joklik ◽  
...  
Keyword(s):  
Natural Gas ◽  
Ignition Delay ◽  
Pilot Scale ◽  
Combustion Characteristics ◽  
Premixed Combustion ◽  
Fuel Oil ◽  
Liquid Fuels ◽  
Nox Formation ◽  
Lean Premixed Combustion ◽  
Lean Premixed

Dry low Emissions (DLE) systems employing lean, premixed combustion have been successfully used with natural gas in combustion turbines to meet stringent emissions standards. However, the burning of liquid fuels in DLE systems is still a challenging task due to the complexities of fuel vaporization and air premixing. Lean, Premixed, Prevaporized (LPP) combustion has always provided the promise of obtaining low pollutant emissions while burning liquid fuels such as kerosene and fuel oil. Because of the short ignition delay times of these fuels at elevated temperatures, the autoignition of vaporized higher hydrocarbons typical of most practical liquid fuels has proven difficult to overcome when burning in lean, premixed mode. To avoid this autoignition problem, developers of LPP combustion systems have focused mainly on designing premixers and combustors that permit rapid mixing and combustion of fuels before spontaneous ignition of the fuel can occur. However, none of the reported works in the literature has looked at altering fuel combustion characteristics in order to delay the onset of ignition in lean, premixed combustion systems. The work presented in this paper describes the development of a patented low-NOx LPP system for combustion of liquid fuels which modifies the fuel rather than the combustion hardware in order to achieve LPP combustion. In the initial phase of the development, laboratory-scale experiments were performed to study the combustion characteristics, such as ignition delay time and NOx formation, of the liquids fuels that were vaporized into gaseous form in the presence of nitrogen diluent. In phase two, an LPP combustion system was commissioned to perform pilot-scale tests on commercial turbine combustor hardware. These pilot-scale tests were conducted at typical compressor discharge temperatures and at both atmospheric and high pressures. In this study, vaporization of the liquid fuel in an inert environment has been shown to be a viable method for delaying autoignition and for generating a gaseous fuel stream with characteristics similar to natural gas. Tests conducted in both atmospheric and high pressure combustor rigs utilizing swirl-stabilized burners designed for natural gas demonstrated operation similar to that obtained when burning natural gas. Emissions levels were similar for both the LPP fuels (fuel oil #1 and #2) and natural gas, with any differences ascribed to the fuel-bound nitrogen present in the liquid fuels. Extended lean operation was observed for the liquid fuels as a result of the wider lean flammability range for these fuels compared with natural gas. Premature ignition of the LPP fuel was controlled by the level of inert gas in the vaporization process.

CFD Simulation of a Low NOx Oil Fired Boiler

2005 ◽  
Author(s):  
C. Hochenauer ◽  
G. Brandstetter
Keyword(s):  
Cfd Simulation ◽  
Nox Reduction ◽  
Fuel Oil ◽  
Detailed Chemical Kinetics ◽  
Heavy Fuel Oil ◽  
Two Phase ◽  
Boiler Load ◽  
Excess Air ◽  
Wide Range ◽  
The Impact

This paper compares the results of an advanced CFD calculation with measurements of a heavy fuel oil fired low NOx boiler. First, a state of the art boiler was investigated and the impact of boiler load and excess air on the NOx emissions was measured. In a second test run a staged combustion technology was integrated using the over fire air concept. The over fire technology is well known and well tested in coal fired boilers. In this pilot boiler it was shown that the over fire air technology could be used for oil fired boilers, too — leading to an enormous NOx reduction without any increase in CO and soot emissions. It was shown that the influence of boiler load, excess air and over fire air on the NOx and CO emissions can be predicted very well in the CFD calculation. Detailed numerical investigations showed that two-phase effects, a good turbulence model, gas and soot radiation and a detailed chemical kinetics mechanism are a must when modeling (staged) heavy oil combustion. The results of the CFD calculation showed an excellent agreement with the measurements over a very wide range of boiler settings and load factors although NOx is extremely difficult to predict.

Wellhead Natural Gas Price Determination – Some Comments

1992 ◽  
Vol 10 (6) ◽  
pp. 422-428
Author(s):  
John H. Herbert
Keyword(s):  
Natural Gas ◽  
Fuel Oil ◽  
Institutional Changes ◽  
Price Determination ◽  
Residual Fuel Oil ◽  
Gas Price ◽  
The Relationship

In this note we examine the relationship between the wellhead price of natural gas and institutional changes in the industry and other factors that influence this price. As part of this examination we estimate an equation to summarize the monthly relationship between the price of natural gas at the wellhead and the price of residual fuel oil and other variables between January 1987 and December 1991.

scholarly journals Applications of oxygen for NOx control and CO2 capture in coal-fired power plants

2006 ◽  
Vol 10 (3) ◽  
pp. 119-142 ◽  
Author(s):  
Fabienne Châtel-Pélage ◽  
Rajani Varagani ◽  
Pavol Pranda ◽  
Nicolas Perrin ◽  
Hamid Farzan ◽  
...  
Keyword(s):  
Co2 Capture ◽  
Power Plants ◽  
Nox Reduction ◽  
Cost Effective ◽  
Pilot Scale ◽  
Capital Requirements ◽  
Pure Oxygen ◽  
Gas Treatment ◽  
Nox Control ◽  
The Cost

Two promising combustion modification approaches applicable to pulverized coal fired boilers are presented: "Oxygen-Enriched Combustion" (OEC) for NOx control and "Oxy-Combustion" (PC-OC) for CO2 capture. Oxygen-enriched air rather than air is used as an oxidizer in the OEC technology. Unlike flue gas treatment technologies, OEC directly impacts the NOx formation process by significantly reducing the conversion of coal bound nitrogen to NOx. Pilot-scale and full-scale tests have shown 20 to 30% NOx reduction from an optimized staged-air baseline. In addition to the overall cost competitiveness and the reduced capital requirements, other significant advantages of the O2-enriched technology vs. existing low NOx technologies are presented. The PC-OC technology is shown as a cost-effective technology for CO2 capture from existing or new coal-fired power plants. Pure oxygen diluted in recycled flue gases is used as an oxidizer. The process has been successfully demonstrated and extensively characterized at pilot-scale level (1.5 MWt). The tests have shown substantial benefits of the PC-OC technology, in terms of NOx reduction (60-70% from air-baseline), overall plant efficiency, etc. The cost effectiveness of this capture technology compared to competitive amine scrubbing technology was investigated. The cost of CO2 avoided was around $36/ton for the new PC-OC cases, about $48/ton on a retrofit PC-OC case, which is about 25 to 40% cheaper than the amine scrubbing system. Those numbers were calculated for sub-critical units and include the cost of CO2 compression up to 80 bar. .

scholarly journals Changes in Greek industry and their effect on air pollutant emissions

2013 ◽  
Vol 11 (4) ◽  
pp. 518-527
Keyword(s):  
Natural Gas ◽  
Emission Reduction ◽  
Energy Use ◽  
Air Pollutant ◽  
Fuel Oil ◽  
Pollutant Emissions ◽  
Industrial Equipment ◽  
Residual Fuel Oil ◽  
Production Processes ◽  
Gas Penetration

Energy use in Greek Industry, fuel mix changes and contribution of major sectors from 1960 to 2004 are presented and analysed. Energy related air pollutant emissions are estimated and presented too. Energy use in Industry has shown a growing trend. Residual fuel oil was the predominant energy form, but with decreasing share, while electricity had a remarkable and steadily increasing share, reflecting changes in industrial equipment towards more automated production processes. Natural Gas started to contribute to energy mix in late ’90s. Emissions followed energy’s growth but with lower rates, since ‘dirty fuels’ use grew slower than electricity, which is a ‘clean fuel’ in final uses. Sectors with the greater contribution in energy use and air pollutant emissions were ‘Basic Metals’ and ‘Chemical’ from 1960 to 1975, while after 1985 ‘Non-metallic Minerals’ and ‘Energy’ sectors had the greater contribution. More than 50% of the countries industrial units are located close to Athens. In 2003, Attica’s share to total industry’s emissions was lower than the share of industries, while neighbouring prefectures’ share was higher. The share of ‘dirty’ industries is higher in the neighbouring to Attica prefectures, while in Attica the share of industries using mainly electricity (‘clean’ final energy form) is higher. The enlargement of natural gas penetration together with energy saving measures will affect positive any emission reduction policy.

scholarly journals Investigation of Co–Fe–Al Catalysts for High-Calorific Synthetic Natural Gas Production: Pilot-Scale Synthesis of Catalysts

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 105
Author(s):  
Tae Young Kim ◽  
Seong Bin Jo ◽  
Jin Hyeok Woo ◽  
Jong Heon Lee ◽  
Ragupathy Dhanusuraman ◽  
...  
Keyword(s):  
Natural Gas ◽  
Spinel Phase ◽  
Space Velocity ◽  
Pilot Scale ◽  
Gas Production ◽  
Laboratory Scale ◽  
Optimum Conditions ◽  
Synthetic Natural Gas ◽  
Co Conversion ◽  
Ft Ir

Co–Fe–Al catalysts prepared using coprecipitation at laboratory scale were investigated and extended to pilot scale for high-calorific synthetic natural gas. The Co–Fe–Al catalysts with different metal loadings were analyzed using BET, XRD, H2-TPR, and FT-IR. An increase in the metal loading of the Co–Fe–Al catalysts showed low spinel phase ratio, leading to an improvement in reducibility. Among the catalysts, 40CFAl catalyst prepared at laboratory scale afforded the highest C2–C4 hydrocarbon time yield, and this catalyst was successfully reproduced at the pilot scale. The pelletized catalyst prepared at pilot scale showed high CO conversion (87.6%), high light hydrocarbon selectivity (CH4 59.3% and C2–C4 18.8%), and low byproduct amounts (C5+: 4.1% and CO2: 17.8%) under optimum conditions (space velocity: 4000 mL/g/h, 350 °C, and 20 bar).

Demonstration of 0.1 MWth pilot-scale pressurized oxy-fuel combustion for unpurified natural gas without CO2 dilution

Energy ◽  
2021 ◽  
Vol 223 ◽  
pp. 120021
Author(s):  
Donghee Kim ◽  
Won Yang ◽  
Kang Y. Huh ◽  
Youngjae Lee
Keyword(s):  
Natural Gas ◽  
Pilot Scale ◽  
Fuel Combustion
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