Gasification and chemical looping effects
Lead Research Organisation:
University of Cambridge
Department Name: Chemical Engineering and Biotechnology
Abstract
The proposed research will investigate the gasification process including pre-treatment of the biomass, fluidised bed gasification
behaviour and the effect of oxides on syngas quality. Fluidised bed experimentation with a range of biomass as well as mathematical modelling will be
utilised for this. Greater control over the process will allow a regulated output of syn-gas from a range of species of biomass and should form the starting
point for a greater variety of uses of the syn-gas including Fisher-Tropcsh synthesis, gas-fermentation, power production and, the so called, "bio-refinery".
Potentially this research could contribute to a future de-coupling of the chemical industry from fossil sources.
behaviour and the effect of oxides on syngas quality. Fluidised bed experimentation with a range of biomass as well as mathematical modelling will be
utilised for this. Greater control over the process will allow a regulated output of syn-gas from a range of species of biomass and should form the starting
point for a greater variety of uses of the syn-gas including Fisher-Tropcsh synthesis, gas-fermentation, power production and, the so called, "bio-refinery".
Potentially this research could contribute to a future de-coupling of the chemical industry from fossil sources.
People |
ORCID iD |
| John Dennis (Primary Supervisor) | |
| Zachariah Bond (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509620/1 | 01/10/2016 | 30/09/2022 | |||
| 1776285 | Studentship | EP/N509620/1 | 01/10/2016 | 30/09/2020 | Zachariah Bond |
| Description | A new model for heat transfer from a bubbling fluidised bed to the surface of a solid particle which is emitting gas has been developed. This has applications mainly in the combustion and gasification of solid fuels with a high percentage of volatile matter. The volatile matter is given off rapidly as the particle is heating up and generates bubbles within the fluidised material which drastically reduces the heat transfer coefficient to the fuel particle. A paper is being written at the time of this researchfish submission on the matter. This is part of the larger project to understand the conditions which promote unconverted volatile matter entering the exhaust gas as a consequence of solid fuel particles floating atop the fluidised medium and, as a result, reducing the quality of the exhaust gas and the efficiency of the conversion of the fuel to either syngas or heat energy. I presented the concept of a model which links the density of the fuel and devolatilisation velocity to the amount of time spent at the surface of the bed at the International Conference on Negative CO2 emissions. The talk received interest from parties operating pilot scale chemical looping processes which suffer heavily from the problem described above. The theory from years 1 - 3 of this project which governs the depth at which a particle sits (and therefore the heat transfer from the bed to the fuel particle) has been largely dis-proven experimentally. In year 4 I performed new experiments to investigate how the emission of gas alters the structure of the bed and have used these to develope a new theory for inert and gas emitting particle buoyancy. This is now being tied together with the previous experimental work whilst writing the thesis. In bed architecture for trapping fuel particles below the surface of a fluidised bed and for distributing the volatile matter has been designed and investigated and shown to be a possible means of reducing accumulation of fuel particles at the surface of the fluidised bed. |
| Exploitation Route | The model will be used to help predict the devolatilisation behavior (rate of emission of gas, total time of emission of gas) of solid fuel particles in air blown and chemical looping combustion and gasification processes. It might, as a result, remove some of the uncertainty associated with the design or configuration of combustors and gasifiers handling fuels with a high volatile content such as waste plastics, sewage sludge and biomass. The model may also be of benefit in the design of fluidised bed dryers for crops and any other process where a solid emits a gas at a velocity similar to or higher than the fluidisation velocity and is controlled by heat transfer. The in bed architecture will also be of great benefit to fluidised bed combustion and gasification of wood. |
| Sectors | Agriculture, Food and Drink,Energy,Environment |
| Description | X-ray imaging of wood fuel particles in fluidised beds |
| Organisation | University College London |
| Country | United Kingdom |
| Sector | Academic/University |
| PI Contribution | Set up of sampling system for analysis of devolatilising particles, explanation of deconvolution for data processing, direction and performance of experiments with beech particles. |
| Collaborator Contribution | Provision of X-ray imaging and large fluidised bed rig, provision of expertise in operating the X-ray rig. |
| Impact | Tying together the gas analysis and the X-ray image analysis to understand the depth at which particles float, given the velocity of gas produced at their surface. The design of under-bed structures to improve the efficiency of combustion and gasification of wood particles in fluidised beds. |
| Start Year | 2019 |
| Description | Department research showcase film |
| Form Of Engagement Activity | A broadcast e.g. TV/radio/film/podcast (other than news/press) |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Postgraduate students |
| Results and Impact | A film was created to showcase the research themes of the department in order to advertise to prospective students and post-doc researchers, as well as potential industrial sponsors. |
| Year(s) Of Engagement Activity | 2018 |
| URL | https://www.youtube.com/watch?time_continue=271&v=vDaVFJHIY6k |