Gasifier construction and demonstration.pptx

Gasifier construction

1. System of Extracting Heat Energy From Wood Exhaust for Fueling an Internal Combustion Engine Design Project 1 and 2

2. Group Members MM/20/0486 - K.H.S.Sandeepa MM/20/0501 - M.V.S.Yasas MM/20/0504 - J.Sugitharan Group No: 21

3. Principles of Gasification Gasification is defined as the conversion of biomass into a gaseous-energy carrier by means of partial oxidation at the elevated temperature. This process involves a sequence of chemical and thermal reactions like the oxidation and reduction. Gasification process convert solid biomass with a limited quantity of air into Producer gas.

4. Producer Gas Producer gas, the gas generated when wood, charcoal or coal is gasified with air, consists of some 40 % combustible gases, mainly carbon monoxide, hydrogen and some methane. The rest are non-combustible and consists mainly of nitrogen, carbon dioxide and water vapor. Producer gas is a mixture of combustible (Hydrogen (13-19%), Methane(1-5%) and Carbon Monoxide (18-22%)} and non-combustible {Nitrogen(45-55%), Carbon dioxide (9-12%)} gases. The producer gas has a calorific value ranging from 1000 to 1200kcal/Nm³. The gas also contains condensable tar, acids and dust as impurities. These impurities may lead to operational problems and abnormal engine wear.

5. Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 Harvesting Processing Chopping Briquetting Dehydration Drying Biomass Gasification Gas Cleaning Boiler Turbine Motor Complete Gasification Process Gasification Process

6. Gasification Process of Biomass 1.Drying 100-150 ° C 2.Pyrolysis 200-500°C 3.Combustion 800-1200 ° C 4.Reduction 650-900 ° C BIOMASS H₂ O + C H + CO CO₂ + C 2CO H₂O Vapour DRY BIOMASS TAR GASES CHARCOAL H₂ O + CO ₂ CRACKED TAR HOT REACTIVE CHARCOAL

7. Thermo-Chemical Process in Gasifier H₂O Charcoal and Tar H₂O and CO2 H2 and CO biomass (CHO) biomass (CHO) tarry gas or charcoal hot charcoal (C) Heat heat no air O₂/air CO₂ and H₂O Drying Pyrolysis Combustion Reduction

8. Types of Gasifiers Fixed-bed gasifiers Updraft gasifiers (Counter current) Downdraft gasifier (Co-counter current) Crossdraft gasifier(Cross current) 2) Fluidized bed gasifiers.

9. Downdraft Gasifier A solution to the problem of tar entrainment in the gas stream has been found by designing co-current or downdraught gasifiers. Primary gasification air is introduced at or above the oxidation zone in the gasifier. The producer gas is removed at the bottom of the apparatus.

10. Updraft Gasifier Blower Assembly

11. Air flow is upward and the gas leaves at the top. Near the grate at the bottom the combustion reactions occur , which are followed by reduction reactions. In the upper part of the gasifier, heating and pyrolysis of the feedstock occur as a result of heat transfer by forced convection and radiation from the lower zones. The tars and volatiles produced during this process will be carried in the gas stream. Ashes are removed from the bottom of the gasifier.

12. Cyclone outlet - Air flows up the center of the cyclone cone and out of the outlet tube to the shop vac or dust collector . Cyclone inlet - connects to the hose used to vacuum up dust and debris . A 2:1 inlet port aspect ratio is close to optimum to achieve the maximum separation efficiency . The air is buoyant so it flows back up and out the outlet pipe at the top. Purpose of the cyclone separator

13. Creosote (tar) eliminating mechanism If be deposited creosote can encourage larger safety concerns hence they must be eliminated from the hot gas flow The cyclone separator disrupting the momentum of the hot gas as going down inside the separator Meanwhile , more heavy creosote particles are getting condensed in to liquid and can be collected by the bottom of the separator

14. Mechanism of the Tar Removing Fiber filter This filter is completely filled with cotton because it is made out of small fibers . COTTON is the most widely produced natural fiber on the planet. The gaseous molecules can penetrate these fibers but relatively larger tar particles and other solid impurities cannot penetrate the cotton layers.

15. Condensing / Cooling of the Wood Gas Air cooling is a method of dissipating heat It works by expanding the surface area or increasing the flow of air over the object to be cooled , or both On this occasion, hot wood gas flowing through the radiator and the aluminum fins of the radiator help to expand the contact area for rapid heat exchange between internal wood gas and ambient air Hence the wood gas coming out of the radiator is condensed (more energy dense ) and free of moisture

16. Achievements We were able to produce synthesis gas from Carbonaceous materials. Through gasification we recovered more energy and higher heat capacity in contrast to Pyrolysis and combustion. Via this project, the use of the fossil fuels can be reduced and waste gasification is used to enhance programs for recycling. Pure wood charcol which is a by product of this system's operation can be used for as a alternative for Coal. Furthermore purification of creosote can will lead to the generation of useful low grade fuel which can be an option for boiler fael .

17. References National Institute of Technology, Srinagar(Retrieved March 09, 2024, from https://www.nitsri.ac.in / ) Bioeconomy Institute(Retrieved March 15, 2024, from -Bioeconomy Institute (iastate.edu)) Alternative Energy Promotion Centre(Retrieved March 15, 2024, from -AEPC) Bio Energy Association of Sri Lanka(Retrieved March 15, 2024, from - Bio Energy Association of Sri Lanka (bioenergysrilanka.lk ]) Food and Agriculture Organization of the United Nations(Retrieved March 15, 2024, from https ://www.fao.org/home/en)

18. Thank You