The NO and N2O formation mechanism during devolatilization and char combustion under fluidized-bed conditions

Winter, Franz; Wartha, Christian; Löffler, G.; Hofbauer, Hermann

doi:10.1016/s0082-0784(96)80180-9

Cited by 112 publications

(54 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The ratio of HCN to NH, was assumed as 99 to 1 based on previous findings that HCN is the dominating nitrogen containing devolatilization product for coals (Chen et al, 1982). During char combustion, the fuel nitrogen partly undergoes heterogeneous oxidation to NO and is partly released as HCN (Winter et al, 1996a). The heterogeneous The measured concentration profiles of CO, CO, and 0,, as well as the riser temperature, are used as input parameters of the model.…”

Section: The Single Particle No/n20 Formation Modelmentioning

confidence: 99%

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

et al. 1999

Self Cite

View full text Add to dashboard Cite

The NO and N,O formation mechanism is studied starting from a single fuel particle burning under well-defined conditions up to a pilot-scale circulating fluidized bed combustor (CFBC). The fuel, petroleum coke, was the same in all tests and care has been taken to obtain chemical similarity between the different units: a formation rate unit, a laboratoryscale and a pilot-scale CFBC. A detailed single particle NO/N20 formation model has been developed and incorporated in a CFBC NO/N,O emission model. To thoroughly test the modeled NOM,O mechanism, the iodine addition method has been used in all units.

show abstract

Section: The Single Particle No/n20 Formation Modelmentioning

confidence: 99%

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

et al. 1999

Self Cite

View full text Add to dashboard Cite

show abstract

“…The other is a homogeneous reaction that follows the release of HCN from the char. [21][22][23][24][25] First, char-nitrogen is oxidized to release HCN. In the second step, HCN reacts with NO molecule in the gas phase to produce N 2 O.…”

Section: Introductionmentioning

confidence: 99%

“…26 Also, the addition of iodine to the combustion chamber at fluidized bed conditions resulted in decreasing the N 2 O concentration while increasing the NO and HCN concentrations. [23][24][25] The authors suggested that iodine decreases the radical concentration stopping the second reaction in the (M2) mechanism above. An extended review concerning N 2 O evolution from (M1) and (M2) mechanisms has been recently prepared.…”

Section: Introductionmentioning

confidence: 99%

Application of Density Functional Theory to the Study of the Reaction of NO with Char-Bound Nitrogen during Combustion

2000

View full text Add to dashboard Cite

The reaction of NO with char-bound nitrogen was studied using four model structures to represent the nitrogen left with the char when coal is devolatilized. The calculations were carried out to simulate combustion conditions resulting in the absence and presence of preadsorbed oxygen on the char. Density Functional theory at the B3LYP/6-31G(d) level was used to optimize the geometries of reactants, NO adsorption complexes, and products. Schematic energy profiles for each reaction were obtained in order to elucidate mechanisms for N 2 O evolution. We found that the NO molecule reacts with char-containing nitrogen to release predominantly N 2 and CO to the gas phase. For the model char structures studied, the presence of adsorbed oxygen on the char-containing nitrogen enhances the reduction of the NO molecule to N 2 as a predominant product of the reaction, but N 2 O can also be released as a minor nitrogen product.

show abstract

“…NO x emission from CFB combustion are well studied in the literature [54,55]. Various factors, such as coal type, bed temperature, air staging, and limestone, can affect the NO x emission from CFB.…”

Section: Formation and Reduction Of No X In Cfb Combustionmentioning

confidence: 99%

Progress of circulating fluidized bed combustion technology in China: a review

Cai

Lyu

et al. 2017

Clean Energy

View full text Add to dashboard Cite

Circulating fluidized bed (CFB) technology plays an important role in the utilization of low-grade coal in China. This article reviews CFB combustion technology development in China and summarizes recent achievements. Since 1990 Chinese engineers and researchers have been undertaking work to improve CFB boiler technology. A completely novel CFB boiler design theory was developed and used in the domestic manufacturing of CFB boilers with various capacities. China is the largest supplier and customer of CFB boilers in the world due to the widespread use of CFB boilers. In 2007, the lower energy consumption CFB technology was successfully developed by re-specifying the fluidization state, which reduced the power consumption of forced fans and solved the potential erosion problems on the water wall. Afterwards, in order to increase the electric power generation efficiency, the supercritical CFB (SCCFB) boiler was developed and the first 600 MW SCCFB boiler was demonstrated and put into commercial operation in 2013. The success of the technology is evident with over 80 SCCFB boilers on order with capacities of 350 MW to 660 MW. Chinese scientists and engineers are also developing technology to lower the emissions of CFB combustion to meet the requirements of China's strict emission regulations. This emission reduction is through high-efficiency desulfurization by limestone injection into the furnace and low NO x combustion, ultra-low emission of SO 2 and NO x in the furnace can be realized by improving the bed quality and increasing the solid circulation rate. There is currently further research and design development being undertaken to develop a 660 MW ultra-supercritical CFB (USCCFB) boiler. The new boiler is expected to be operational before 2020 resulting in higher efficiency and lower energy consumption and emissions.

show abstract

The NO and N2O formation mechanism during devolatilization and char combustion under fluidized-bed conditions

Cited by 112 publications

References 9 publications

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

Application of Density Functional Theory to the Study of the Reaction of NO with Char-Bound Nitrogen during Combustion

Progress of circulating fluidized bed combustion technology in China: a review

Contact Info

Product

Resources

About

The NO and N2O formation mechanism during devolatilization and char combustion under fluidized-bed conditions

Cited by 112 publications

References 9 publications

The NO and N2O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

The NO and N2O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

Application of Density Functional Theory to the Study of the Reaction of NO with Char-Bound Nitrogen during Combustion

Progress of circulating fluidized bed combustion technology in China: a review

Contact Info

Product

Resources

About

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale

The NO and N₂O formation mechanism under circulating fluidized bed combustor conditions: From the single particle to the pilot‐scale