Effect of Mg and K inorganic species on the chars properties derived - PowerPoint PPT Presentation

Effect of Mg and K inorganic species on the chars’ properties derived from grape marc pyrolysis M. Jeguirim, L. Limousy, K. Thabet, L. Josien, L. Michelin, C. Vaulot S. Bennici Université de Haute ‐ alsace, CNRS, IS2M UMR7361, F ‐ 68100 Mulhouse, France e ‐ mail : simona.bennici@uha.fr 1

BACKGROUND To diminish greenhouse gas emission (CO 2 ) Renewable: biomass energy is a renewable resource. Dependency on fossil Fuels is reduced. Carbon Neutral. Widely Available. Helps Reduce Waste . Can be used in various forms. It can be used to produce methane gas, biodiesel and other biofuels. It can also be used to directly generate heat or to generate electricity using a steam turbine. It can produce chars , with a wide panel of applications. Various sources 2

WINERY WASTE VALORISATION PROCESSES Grape marc residues as renewable resource Grape marc residue has a high lignin and ash contents ensuring good potential for biochar production. Grape marc is worldwide available since 70 million tons of wine grape are annually produced. Up to 20% of the harvested wine becomes waste during wine production (stalks and seeds grape, skins). Biomass wastes can be transformed into clean energy and/or fuels by a variety of technologies. Thermochemical conversion Combustion Gasification Pyrolysis 3

GRAPE MARC VALORISATION PROCESSES: ECONOMIC VIABILITY Annual cash flow for investment in combustion and pyrolysis Small wineries with a grape crush under 50 tons at different winery scales show the insignificance of the potential revenue and savings in comparison to the cost of the capital investment. For bigger size wineries, the potential revenue and savings increase when compared to the investment costs. Pyrolysis is seen to result in a net positive cash flow for wineries with a grape crush over 1000 tons. As comparison, combustion approaches, but never reaches, the break ‐ even point in wineries with an annual grape crush over 10000 tons. From Zhang et al. Waste Management, 60, 2017, 173 ‐ 183 4

GRAPE MARC COMPOSITION Cellulose Hemicellulose Lignine Their presence modifies the thermal behaviour of biomass Inorganics Mg, K, Ca, Na… Contradictions on their catalytic or inhibitor behaviour 5

CHARS’ PREPARATION Effect of inorganics on the chars’ morphological and structural properties Impact of inorganics on the pyrolysis kinetics Gas Oil Grape marc Pyrolysis at Granulometry: I mpregnation 300 ‐ 500 ° C Char 0.25 ‐ 0.40 mm Mg and K salt under N 2 flow Washing Physico ‐ chemical characterization 6

PYROLYSIS: BIOMASS FRACTION DEGRADATION 5 °C/min, 100 mL/min N 2 100 0,035 100 0,035 ATG-MR-B-500(5) ATG-MR-B-500(5) 90 90 DTG-MR-B-500(5) 0,03 DTG-MR-B-500(5) 0,03 80 80 0,025 70 0,025 70 60 60 Mass (%) 0,02 -DTG(%/s) Masse(%) Mass (%) 0,02 -DTG(%/s) Masse(%) 50 50 0,015 0,015 40 40 30 0,01 30 0,01 20 20 0,005 0,005 10 10 0 0 0 0 120 0 100 200 300 400 500 600 0,3 120 0 100 200 300 400 500 600 0,01 Temperature(°C) ATG-Cell-com-B-500(5) Temperature(°C) ATG ‐ Hem ‐ mais(500) ‐ 5 DTG-Cell-com-B-500(5) DTG ‐ Hem ‐ mais(500) ‐ 5 0,25 100 100 0,008 0,2 80 80 0,006 Pure cellulose Pure hemicellulose -DTG(%/s) 0,15 Mass (%) Masse (%) Mass (%) Mass (%) ‐ DTG (%/s) 60 60 0,004 0,1 40 0,05 40 0,002 20 0 20 0 0 -0,05 0 100 200 300 400 500 600 0 ‐ 0,002 0 100 200 300 400 500 600 Température (°C) Temperature (°C) Cellulose 7 Hemicellulose (not pure)

CHARS’ CHARACTERIZATION: XRF AND TG Inorganics addition XRF 0,045 0,04 0,035 0,03 MR ‐ L ‐ 500(5) 0,025 DTG (%/S) MR ‐ L ‐ 500(5) MR ‐ K ‐ 500(5) 0,02 MR ‐ K ‐ 500(5) MR ‐ Mg ‐ 500(5)" MR ‐ Mg ‐ 500(5) MR ‐ B ‐ 500(5) 0,015 MR ‐ B ‐ 500(5) 0,01 0,005 0 100 150 200 250 300 350 400 450 500 ‐ 0,005 Temperature (°C) KCl addition: MgCl 2 addition: Higher cellulose degradation rate Lower hemicellulose degradation T The char obtained by the original (0.032 %s ‐ 1 ) Much lower cellulose degradation rate grape marc presents a high content Lower hemicellulose degradation T (0.024 %s ‐ 1 ) of inorganics Lower cellulose degradation T A different effect of the various salts is observed in Addition of KCl and MgCl 2 was done relation with the biomass fraction on the washed biomass 8

PYROLYSIS: ACTIVATION ENERGIES Kissinger equation: 0,1 MR-B-500(3) MR-B-500(5) 0,09 MR-B-500(10) 0,08 MR-B-500(15)  K/min 0,07 MR ‐ B MR ‐ L MR ‐ K MR ‐ Mg 0,06 DTG(%/s) 0,05 E a (kJ/mol ‐ 1 ) 190 181 188 273 Cellulose 0,04 0,03 0,02 E a (kJ/mol ‐ 1 ) 198 160 141 123 Hémicellulose 0,01 0 0 2000 4000 6000 8000 10000 12000 Temps (s) Time (s) KCl addition ‐ Lower activation energy for hemicellulose degradation  Catalytic effect ‐ No impact on the cellulose degradation MgCl ₂ addition ‐ Higher activation energy for cellulose degradation  Inhibitor effect ‐ Lower activation energy for hemicellulose degradation  Catalytic effect Different effect in relation to the different biomass fractions Impact of the biomass washing on the hemicellulose transformation 9

CHARS’ CHARACTERIZATION: CO 2 ‐ ADS ISOTHERMS and SEM Char derived CO 2 adsorption isotherms: Char morphology after washing from grape marc surface area and pores volume and salts addition of the parent biomass Sample S CO2 V P,CO2 (<1nm) MR-L-500 MR-L-500 MR-B- 500 (m 2 /g) (cm 3 /g) MR ‐ B ‐ 500 189 0.054 MR ‐ L ‐ 500 213 0.059 MR ‐ K ‐ 500 225 0.065 MR ‐ Mg ‐ 500 220 0.061 MR-K-500 MR-K-500 Surface area and porosity increase by washing Cohesion loss of the carbon matrix MR-Mg-500 MR-Mg-500 KCl is visible as well defined crystals Good dispersion of MgCl 2 10

CHARS’ CHARACTERIZATION: INFRARED ANALYSIS Char functionalities at increasing pyrolysis T Char functionalities: salts addition (T py =300°C) C ‐ H aliphatic C=0 aliphatic O ‐ H Intensity (A.U) Intensity (A.U) T 300°C 400°C 500°C Wavelength (cm ‐ 1) Wavelength (cm ‐ 1) Decreasing of the 1747 cm ‐ 1 bands Loss of aliphatic groups at high pyrolysis T at 300 °C in presence of salts Decreasing of the aliphatic C=O band, degradation of volatiles Decomposition of aliphatic esters New C=C groups detected at higher T, formation of aromatic compounds 11

CHARS’ CHARACTERIZATION: CHARS YIELD (BY TG) AND RAMAN D G 30000 MR-B-500 MR-B-500 ↑ T MR-L-500 MR-L-500 ↑ [salt] MR-K-500 MR-K-500 25000 MR-Mg-500 MR-Mg-500 Intensity (A.U) 20000 Yield (%) ) ( 15000 10000 5000 0 0 500 1000 1500 2000 2500 3000 3500 Wavelength (cm ‐ 1) Echantillon D G I D /I G The char yield decreases with the T MR ‐ B ‐ 400 1341 1575 0,97 MR ‐ B ‐ 500 1341 1581 0,95 MR ‐ L ‐ 500 1354 1579 0,97 Volatiles production at high temperature MR ‐ K ‐ 500 1345 1579 0,94 MR ‐ Mg ‐ 500 1345 1585 0,93 Salts addition bring to the slight increasing ID/IG slightly decreases by increasing the pyrolysis T of the char yield ID/IG slightly decreases with the addition of inorganics Formation of more extended aromatic systems (graphitization) 12

CONCLUSIONS KCl and MgCl 2 salts display catalytic or inhibitor behaviors in dependence of the biomass fraction. MgCl 2 decreases the E a of hemicellulose degradation, while increases that of cellulose. Other parameters, as the biomass washing, has to be taken into account not to misunderstand the inorganics impact during biomass pyrolysis In presence of salts, the decomposition of aliphatic esters takes place at lower pyrolysis T. Salts addition brings to a slight increase of the char yield, probably due to the formation of more extended aromatic systems (graphitization), thus producing chars with higher specific surface and enhanced porosity. Pyrolysis of grape marc enriched in inorganics (possibly deriving from waste effluents) can be potentially used to produce high quality chars at lower pyrolysis temperature than that usually applied. 13

Acknowledgement to: The MICA Carnot Institute for the economical support in the frame of the Carbovit project. 14

…. THANK YOU !!! 15