Influence of oxidizer injection angle on the entrained flow gasification of torrefied wood powder

Ögren, Yngve; Gullberg, Marcus; Wennebro, Jonas; Sepman, Alexey; Tóth, Pál; Wiinikka, Henrik

doi:10.1016/j.fuproc.2018.09.005

Cited by 20 publications

(8 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A detailed description of the tunable diode laser absorption spectroscopy (TDLAS) system near 7154 cm –1 and the method for evaluation of temperature and H 2 O concentration was given in our previous studies. , In brief, the laser wavelength from the system consisting of fiber-coupled distributed feedback laser (Nanoplus GmbH) was controlled by a Thorlabs benchtop laser diode/TEC controller (ITC4001). The controller was tuned over a range of up to ∼2.5 cm –1 via the modulation of the driving current by using a 100 Hz triangular voltage signal at a constant diode temperature (41 °C).…”

Section: Materials and Methodsmentioning

confidence: 99%

Combustion Evaluation of Renewable Fuels for Iron-Ore Pellet Induration

et al. 2019

Self Cite

View full text Add to dashboard Cite

Induration (or sintering) of iron-ore pellets requires high temperature (∼1300 °C), which today is generated by burning fuel oil in the firing zone of the straight-grate plant (SG) or coal in the rotary kiln of grate-kiln (GK) plants. In this study, ∼150 kW th combustion experiments were used to investigate the opportunity of totally replacing fuel oil with H 2 or pyrolysis oil and replacing coal with wood pellets or black pellets powder. For SG plants, the fuel oil can probably be replaced with either H 2 or pyrolysis oil without any major concerns, except for slightly or much higher NO x emissions in the case of pyrolysis oil and H 2 , respectively. For GK induration machines, it is probably challenging to replace coal entirely with biomass since the temperature profile will be different, and there is a risk for increased ash related operational problems. For both SG and GK plants, the slightly lower O 2 concentration in the flue gas observed during biomass combustion (pyrolysis oil, wood pellets, and black pellets) may, however, be negative for the induration process, and this needs to be clarified in future research.

show abstract

Section: Materials and Methodsmentioning

confidence: 99%

Combustion Evaluation of Renewable Fuels for Iron-Ore Pellet Induration

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

“…This pilot-scale EFR has previously been used in studies investigating air-blown , and oxygen-blown gasification as well as to test and validate optical diagnostic tools. ,,,, The EFR walls were well-insulated, preheated by oil combustion, and heated by the conversion process itself to minimize temperature gradients and boundary layer effects along the radial line-of-sight across the reactor core. Prior work employing the current ,, and a similar EFR, and suction probe measurements across the radial EFR profile (data not shown), suggest that the combustion products are well-mixed and the major species experience homogeneous, close to equilibrium conditions already at port 1.…”

Section: Methodsmentioning

confidence: 99%

Tunable Diode Laser Absorption Spectroscopy Diagnostics of Potassium, Carbon Monoxide, and Soot in Oxygen-Enriched Biomass Combustion Close to Stoichiometry

Sepman

Ögren

et al. 2019

Energy Fuels

Self Cite

View full text Add to dashboard Cite

Combustion facilities run on pulverized biomass often exhibit fluctuations in fuel feeding and, thus, equivalence ratio and would benefit from fast process control based on optical λ sensors installed in the reactor core. The conversion of softwood powder is investigated in an atmospheric entrained-flow reactor (EFR) operated close to stoichiometry using two different burners (swirl and jet) and three oxygen concentrations (21, 30, and 40%). Tunable diode laser absorption spectroscopy (TDLAS) is used to conduct time-resolved (0.1−1 s) in situ measurements of the gas temperature, carbon monoxide (CO), water vapor (H 2 O), gaseous atomic potassium [K(g)], and soot volume fraction in the lower part of the reactor core and in the exhaust of the EFR. At both locations, the measurement parameters show significant, correlating fluctuations. The local equivalence ratio is derived from a comparison of measured CO and H 2 O concentrations (for fuel-rich and fuel-lean conditions, respectively) to thermodynamic equilibrium calculations (TEC) and found to vary in a wide range (0.8−1.3). Soot production decreases with an increasing local equivalence ratio and oxygen enrichment and is lower for the swirl compared to the jet burner. The measured K(g) concentrations follow the general behavior predicted by TEC around stoichiometry. In the relevant temperature range (1100−1700 K), K(g) is 2−4 orders of magnitude higher under fuel-rich than fuel-lean conditions, with a sharp transition at stoichiometry. While K(g) concentrations are lower than TEC in the reactor core and under fuel-rich conditions, excellent agreement is found at the exhaust after complete fuel conversion. Precise, wide dynamic range detection of K(g) using TDLAS enables discrimination between fuel-rich and fuel-lean conditions and has the potential for lambda sensing close to the hot reaction zone of combustion plants.

show abstract

“…The same absorption lines have been used in several publications, e.g., [15]. A more detailed description of the system and the process used in this publication can be found in [16,17].…”

Section: Online Tunable Diode Laser Absorption Spectroscopy (Tdlas) Mmentioning

confidence: 99%

Oxygen-Blown Gasification of Pulp Mill Bark Residues for Synthetic Fuel Production

2021

Self Cite

View full text Add to dashboard Cite

Synthetic fuel production via gasification of residual biomass streams from the pulp and paper industry can be an opportunity for the mills to enable improved resource utilization and at the same time reduce the production of excess heat. This paper summarizes initial oxygen-blown gasification experiments with two bark residues from a European pulp and paper mill, i.e., a softwood bark and a hardwood bark. The gasification process was characterized by measuring syngas yields and process efficiency to find optimum operating conditions. In addition, impurities in the syngas and ash behavior were characterized. Maximum yields of CO and H2 were obtained from softwood bark and amounted to approximately 29 and 15 mol/kg fuel, respectively. Optimum cold gas efficiency was achieved at an oxygen stoichiometric ratio of λ = 0.40 and was approximately 76% and 70% for softwood bark and hardwood bark, respectively. Increased λ had a reducing effect on pollutants in the syngas, e.g., higher hydrocarbons, NH3, HCl, and soot. The situation for sulfur species was more complex. Evaluation of the bark ashes indicated that slag formation could start already from 800 °C. Furthermore, a non-intrusive laser diagnostics technique gave rapid feedback on the millisecond scale. Measured syngas temperature and water content were in good agreement with the applied reference methods.

show abstract

Influence of oxidizer injection angle on the entrained flow gasification of torrefied wood powder

Cited by 20 publications

References 33 publications

Combustion Evaluation of Renewable Fuels for Iron-Ore Pellet Induration

Combustion Evaluation of Renewable Fuels for Iron-Ore Pellet Induration

Tunable Diode Laser Absorption Spectroscopy Diagnostics of Potassium, Carbon Monoxide, and Soot in Oxygen-Enriched Biomass Combustion Close to Stoichiometry

Oxygen-Blown Gasification of Pulp Mill Bark Residues for Synthetic Fuel Production

Contact Info

Product

Resources

About