Achievement in ultra-low-load combustion stability for an anthracite- and down-fired boiler after applying novel swirl burners: From laboratory experiments to industrial applications

Wang, Qingxiang; Chen, Zhichao; Li, Liankai; Zeng, Lingyan; Li, Zhengqi

doi:10.1016/j.energy.2019.116623

Cited by 48 publications

(9 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During stable combustion, the maximum temperature in the CC was approximately 1,181°C, and the temperature difference in the 0–3,000 mm zone along the combustion path was within 230°C. In conventional combustion, the temperature difference in the main combustion zone is usually above 500°C 32–34 . Therefore, a more uniform temperature distribution was reached in the main combustion zone under this combustion mode, and there was no local high‐temperature zone in the main combustion zone; the local oxidation zone was avoided.…”

Section: Resultsmentioning

confidence: 99%

“…As the secondary air was injected incrementally, the combustible content in the fuel gradually decreased, and the combustion temperature decreased accordingly. The temperature of the tail flue gas was 619 C. During stable combustion, the maximum temperature in the CC was approximately 1,181 C, and the temperature difference in the 0-3,000 mm zone along the combustion path was within 230 C. In conventional combustion, the temperature difference in the main combustion zone is usually above 500 C. [32][33][34] Therefore, a more uniform temperature distribution was reached in…”

Section: Combustormentioning

confidence: 99%

“…The original emissions of NO x were only 187.2 mg/m 3 (@6% O 2 ), and the conversion ratio of fuel-nitrogen to NO x was approximately 16.6%. Compared with the original NO x emissions (600-800 mg/m 3 @6% O 2 ) in conventional pulverized coal combustion technology, 33,34 the advantages of this technology route are great.…”

Section: Nitrogen Conversionmentioning

confidence: 99%

See 2 more Smart Citations

NO_x emissions of pulverized coal combustion in high‐temperature flue gas

Zhu

Lyu

2020

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

An improved high-temperature flue gas combustion technology was developed and examined in this study. The high-temperature flue gas generator generated a flow of flue gas at a high temperature (720 C) with low oxygen content (10%), which flowed into the main combustion zone and acted as the carrier gas for pulverized bituminous coal (0-0.355 mm) in the combustion chamber. In the combustion chamber, the coal particles reached a higher combustion temperature (>1,100 C) in a short time, and the temperature difference was within 230 C, which showed that the local oxidation zone had been avoided. Furthermore, air-staging combustion technology was also adopted in combination with this technology. NO was the main nitrogen-containing compound, and the concentrations of other nitrogen-containing compounds (N 2 O, NH 3 , and HCN) were extremely low. The NO concentrations were reduced to 0 ppm twice when the volatiles released rapidly in the initial stage, and the volatiles burned violently in the intermediate stage, which are the main reasons for the significant reduction in NO x emissions. The original emissions of NO x were 187.2 mg/m 3 (@6% O 2), and the conversion ratio of fuel-nitrogen to NO x was 16.6%. High-temperature flue gas combustion technology has reached low-NO x combustion for pulverized coal.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Combustormentioning

confidence: 99%

See 1 more Smart Citation

NO_x emissions of pulverized coal combustion in high‐temperature flue gas

Zhu

Lyu

2020

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

show abstract

“…Down‐fired boiler burning anthracite still generally suffers from late ignition and poor combustion stability. The minimum stable operating load rate without oil support is about 50%, 23 which is generally lower than that of tangential‐fired and opposed‐fired boilers. In order to improve the low‐load stable combustion capacity of down‐fired boiler with DC burner, we proposed a novel low‐load stable combustion technology in which the oil‐secondary air was arranged parallel with the fuel‐rich coal/airflow and always put into operation.…”

Section: Introductionmentioning

confidence: 90%

Influence of the parallel oil‐secondary air and F‐layer secondary air distribution on the flow, combustion, and NOx generation characteristics of FW down‐fired boilers retrofitted with a stable combustion technology

Liu

et al. 2022

Asia-Pacific J Chem Eng

Self Cite

View full text Add to dashboard Cite

To further reduce the NOx emissions of the down-fired boiler while improving its low-load stable combustion capacity, a new low NOx combustion organization mode that utilizes the high velocity parallel oil-secondary air to improve the pulverized coal combustion process was proposed based on a novel stable combustion technology. We carried out cold airflow experiments under different oil-secondary air and F-layer secondary air distributions (mass flow rate ratios of 1:9, 1:3, 2:3) based on a 300 MWe Foster Wheeler down-fired boiler to study its influence on the flow and mixing characteristics of the coal/airflow. Results show that the mixing between the oil-secondary air and the fuel-rich coal/airflow is gradually delayed with the increase of the secondary air distribution. When the secondary air distribution reaches more than 2:3, the oilsecondary air starts to become the dominant airflow that influences the whole flow field in the furnace. Based on the result of the cold airflow experiment, we carried out industrial measurements under different parallel oil-secondary air and F-layer secondary air distributions (4:6, 5:5, 6:4) on a 600 MWe FW down-fired boiler under the condition of using the high velocity oil-secondary air. The ignition distance of the fuel-rich coal/airflow, the flue gas temperature, the O 2 , CO, and NOx concentrations in the furnace were measured. At the secondary air distribution of 4:6, the ignition distance of the fuel-rich coal/ airflow was about 1.31 m. When the secondary air distribution was increased to 5:5 and 6:4, the ignition was put off, but the pulverized coal/airflow could still catch on fire in time. With the increase of the parallel oil-secondary air proportion, the flame center in the furnace did not move downward substantially. In three cases, the lowest O 2 concentrations in the inspection port area under the burner were all below 1% (peak CO concentration values were all above 28,000 ppm). The pulverized coal all burned in a strong reducing atmosphere. At secondary air distributions of 4:6, 5:5, and 6:4, NOx emissions of the boiler were, respectively, 825.83, 819.48, and 853.86 mg/Nm 3 (O 2 = 6%). The

show abstract

“…The model parameters of the single decoupling steam turbine are as follows. 34 Figure 6 shows the comparison between the proposed model and the previous model. At the initial stage of response, the response of the double decoupling steam turbine model is 0.2 p.u.…”

Section: Turbine Model Verificationmentioning

confidence: 99%

A new assessment mechanism of primary frequency regulation capability for a supercritical thermal power plant in deep peaking

Hong

et al. 2022

Energy Science & Engineering

View full text Add to dashboard Cite

With the rapid development of renewable energy, the primary frequency control (PFC) is becoming more critical and significant to ensure the stability of the electrical power system. As the main role of PFC, the thermal power unit tends to in a wide operation interval, and the changes in PFC characteristics along with working conditions are inevitable. By decomposing and quantifying the dynamic energy conversion process, this paper proposes a novel mechanism to evaluate the PFC capability for the supercritical thermal power plants that covered 30%–100% of the rated load. In the mechanism, a refined steam turbine model is established to reflect the short‐term dynamic response of PFC by combining it with the coupling characteristics of the main steam valve and main steam pressure in the later phase. Meanwhile, as a new prior assessment index, the equivalent electricity has been put forward to quantify the PFC capability for the power plant. In a case study of a 600 MW supercritical power plant, the capacities of PFC under 30%–50% of the rated load are quantified for the first time. Comparison results between theoretical calculation and real PFC test show that the proposed PFC capability assessment mechanism has acceptable accuracy of 96.1%, which could be effective to assess the frequency response reserve and stability margin in the grid.

show abstract

Achievement in ultra-low-load combustion stability for an anthracite- and down-fired boiler after applying novel swirl burners: From laboratory experiments to industrial applications

Cited by 48 publications

References 41 publications

NO_x emissions of pulverized coal combustion in high‐temperature flue gas

NO_x emissions of pulverized coal combustion in high‐temperature flue gas

Influence of the parallel oil‐secondary air and F‐layer secondary air distribution on the flow, combustion, and NOx generation characteristics of FW down‐fired boilers retrofitted with a stable combustion technology

A new assessment mechanism of primary frequency regulation capability for a supercritical thermal power plant in deep peaking

Contact Info

Product

Resources

About

Achievement in ultra-low-load combustion stability for an anthracite- and down-fired boiler after applying novel swirl burners: From laboratory experiments to industrial applications

Cited by 48 publications

References 41 publications

NOx emissions of pulverized coal combustion in high‐temperature flue gas

NOx emissions of pulverized coal combustion in high‐temperature flue gas

Influence of the parallel oil‐secondary air and F‐layer secondary air distribution on the flow, combustion, and NOx generation characteristics of FW down‐fired boilers retrofitted with a stable combustion technology

A new assessment mechanism of primary frequency regulation capability for a supercritical thermal power plant in deep peaking

Contact Info

Product

Resources

About

NO_x emissions of pulverized coal combustion in high‐temperature flue gas

NO_x emissions of pulverized coal combustion in high‐temperature flue gas