Experimental assessment of woody biomass gasification in a hybridized solar powered reactor featuring direct and indirect heating modes

TLDR: In this article, a hybrid solar-autothermal gasification of mm-sized beech wood particles in a lab-scale 1.5 kWth spouted-bed reactor was investigated.

About: This article is published in International Journal of Hydrogen Energy.The article was published on 2021-10-29 and is currently open access. It has received 13 citations till now. The article focuses on the topics: Syngas & Wood gas generator.

Figures

Table 1. Beech wood characteristics (dry basis).

Figure 7. Yields of syngas components and CGE measured with different oxidizing gases (runs #3, #8, #2, and #4 from left to right).

Table 4. Yields of syngas components, energy breakdown (lower heating values and solar energy absorbed by the reactor), and efficiencies measured during continuous hybrid runs (runs #9 and #10).

Figure 10. Flow rates of syngas components and temperatures measured during continuous hybrid runs, in (a) direct (run #9) and (b) indirect (run #10) heating modes.

Figure 3. Yields of syngas components measured under increasing O2:C molar ratios, in direct (run #1) and indirect (run #2) heating modes.

Figure 2. Flow rates of syngas components measured under different O2 injection rates (run #2).

Frequently asked questions

Q1. What are the contributions in "Experimental assessment of woody biomass gasification in a hybridized solar powered reactor featuring direct and indirect heating modes" ?

This work addresses hybrid solar-autothermal gasification of mm-sized beech wood particles in a lab-scale 1. 5 kWth spouted-bed reactor. The impact of reaction temperature ( 1200-1300°C ) and heating mode ( direct or indirect ) was experimentally studied during both allothermal and hybrid gasification. 

Q2. How was the steam injected in the reactor?

Water steam was then injected continuously in the reactor at a rate of 0.2 g/min, and oxygen and wood were provided at respectiveflow rates of 0.25 NL/min and 1.4 g/min. 

Q3. What was used to measure yields of light gas hydrocarbons?

GC was mainly used to measure yields of light gas hydrocarbons (C2Hm, as the sum of C2H2, C2H4 and C2H6 species, precision of ±1%). 

Q4. How long did the reactor stay steady?

the reactor temperatures stabilized after two minutes of injection, and remained steady despite the variations of syngas production rates. 

Q5. What was the effect of hybridization on the gasifier?

The experimental study of a spouted-bed solar gasifier demonstrated that hybridization was effective to heat the gasifier cavity and compensate for drops of solar power input. 

Q6. What was the temperature of the reactor walls during the hybrid period?

The center of the cavity was thus maintained near its initial temperature (T3 ≈ 1330 °C) during the 10- minute hybrid period, while the reactor walls tended to cool down because of a lower solar power input. 

Q7. How much O2 was injected into the reactor?

As for T2, it increased significantly only when 0.38 NL/min of O2 was injected (until +200 °C in direct heating mode and +50 °C in indirect heating mode), revealing that the quantity of O2 necessary to efficiently heat the reactor walls was higher than 0.25 NL/min.