Developing a sustainable biorefinery from coffee waste
Lead Research Organisation:
University of Bath
Department Name: Chemical Engineering
Abstract
The aim of this project is to assess various novel technologies for the valorisation of this coffee waste into further fuels and chemicals. This will be divided into four key objectives.
In the first objective, the hydrothermal carbonisation process (HDC) will be used to convert coffee grounds into a solid carbon rich fuel, a gas and an aqueous phase containing N, P and other microelements. The process will be optimised through the ramp rate, temperature, solids loading, coffee type and other processing parameters on the batch lab scale. The solids and aqueous phase produced will be analysed for elemental composition, calorific value and molecular structure.
On optimisation of the lab conditions a scoping study will be undertaken to recommend the best scale up technologies, suited to the Bio-Bean processing plant in North London. This will include an estimated energy and mass balance as well as recommendations on the upstream and downstream processing, suitable reactor design and estimated economic impacts.
On completion of the assessment of HDC, we will assess a range of technologies to extract lipid from wet biomass under solvent free conditions. The techniques investigated could be particle explosion/implosion techniques, vortex separations technology or homogenisation followed by an emulsion disruption stage. This will form a key stage in the biorefinery, producing a lipid product prior to the HDC process.
In addition to these key bulk fuel products coffee is well known to possess a range of terpenoid, sterol and other target compounds of interest to the pharmaceutical industry. In this work package the coffee waste will be hydrolysed under varying conditions and the solubilised fractions analysed by HLPC-MS to determine likely high value chemicals suitable for further extraction. This will assess whether higher value products are present in the coffee waste, which could be used as a suitable income stream prior to the HDC / briquette process.
In the first objective, the hydrothermal carbonisation process (HDC) will be used to convert coffee grounds into a solid carbon rich fuel, a gas and an aqueous phase containing N, P and other microelements. The process will be optimised through the ramp rate, temperature, solids loading, coffee type and other processing parameters on the batch lab scale. The solids and aqueous phase produced will be analysed for elemental composition, calorific value and molecular structure.
On optimisation of the lab conditions a scoping study will be undertaken to recommend the best scale up technologies, suited to the Bio-Bean processing plant in North London. This will include an estimated energy and mass balance as well as recommendations on the upstream and downstream processing, suitable reactor design and estimated economic impacts.
On completion of the assessment of HDC, we will assess a range of technologies to extract lipid from wet biomass under solvent free conditions. The techniques investigated could be particle explosion/implosion techniques, vortex separations technology or homogenisation followed by an emulsion disruption stage. This will form a key stage in the biorefinery, producing a lipid product prior to the HDC process.
In addition to these key bulk fuel products coffee is well known to possess a range of terpenoid, sterol and other target compounds of interest to the pharmaceutical industry. In this work package the coffee waste will be hydrolysed under varying conditions and the solubilised fractions analysed by HLPC-MS to determine likely high value chemicals suitable for further extraction. This will assess whether higher value products are present in the coffee waste, which could be used as a suitable income stream prior to the HDC / briquette process.
People |
ORCID iD |
| Christopher Chuck (Primary Supervisor) | |
| Jacqueline MASSAYA (Student) |
Studentship Projects
| Project Reference | Relationship | Related To | Start | End | Student Name |
|---|---|---|---|---|---|
| EP/N509589/1 | 01/10/2016 | 30/09/2021 | |||
| 1942395 | Studentship | EP/N509589/1 | 01/10/2017 | 30/06/2021 | Jacqueline MASSAYA |
| Description | The aim of the project was to valorise coffee waste (SCG) into various high - low value streams within a biorefinery. The objectives included use of novel hydrothermal technologies to isolate a bioactive stream and convert the bulk material into a solid fuel substitute (hydrochar). The major problem was the high nitrogen content in the solids, which are a barrier to the commercial viability of SCG hydrochar (due to limitations on NOx emissions upon combustion). To this end, integration of two hydrothermal processes (subcritical water extraction and hydrothermal carbonisation) with an alkaline pretreatment resulted in the retention of three products: a bioactive aqueous phase, a protein isolate, and a hydrochar with reduced N content (<0.3 %wt). The hydrochar products were explored as horticultural amendments. |
| Exploitation Route | The project is sponsored by Biobean- a firm collecting and valorising SCG. The alkaline pretreatment has been adopted by Biobean to reduce N content in products. |
| Sectors | Agriculture, Food and Drink,Chemicals,Energy |
| Description | bio-bean |
| Organisation | Bio-Bean Ltd |
| Country | United Kingdom |
| Sector | Private |
| PI Contribution | research and development- thermogravimetric characterization of samples and exploration of a pre-processing technique. |
| Collaborator Contribution | provision of spent coffee grounds |
| Impact | Research papers |
| Start Year | 2017 |
| Description | Keynote lecture at SCA EXPO 2019 (Boston, US) |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Public/other audiences |
| Results and Impact | I gave a keynotes lecture at the 2019 SCA EXPO in Boston. The purpose was to inform about/ contextualise current research on the sustainability of coffee waste to a non-scientific audience. The audience was mixed, mostly cafe owners and coffee importers. The lecture sparked questions and several people got in contact afterwards |
| Year(s) Of Engagement Activity | 2019 |