Mitigating Methane Emissions: Conversion of Biogas from Organic Wastes into a High-Value Fish Food Supplement for Aquaculture in Bangladesh
Read the Blog: Chungheon Shin | March 21, 2023 >>
Related: Circular Economy
Transforming Greenhouse Gases into High-Value Aquaculture Feed in Bangladesh
Objective
Develop and optimize biogas-fed methanotrophic reactors that enables provision of a sustainable source of protein and mitigation of greenhouse gas emissions for a circular economy.
Rationale
Why we care about this
According to the UN, the population is predicted to increase to over 9.6 billion people by 2025. This increase in population will accelerate two global issues our society faces today: (1) climate change and (2) world hunger. Population growth increases waste generation, along with anthropogenic methane emissions through landfills and anaerobic digesters that manage solid waste. Globally, waste management constitutes up to 12% of global anthropogenic emissions of methane, a potent greenhouse gas with at least 34 times the global warming potential of carbon dioxide (IPCC). World hunger remains a persistent global challenge, with approximately 690 million people suffering from hunger in 2019. Despite progress in reducing hunger over the past few decades, the COVID-19 pandemic has exacerbated the issue, pushing an additional 130 million people into hunger in 2020. Sustainable solutions are needed to resolve these issues simultaneously..
Why we see the knowledge we are generating as strategic
Methanotrophs (or methane-eating bacteria) can provide a solution that can address both climate change and hunger issues simultaneously. Biogas methane produced from solid waste can be utilized as a feed source for methanotrophs, enabling reproduction of methanotrophs. The methanotrophs can then be used as a single-cell protein (SCP) source to grow fish or poultry that can support our food chain. To date, current industries, including Calysta, already incorporate methanotrophic bioreactors to produce SCP but rely on natural gas (high methane content) as a methane source. This can mitigate the hunger issue but not climate change. To enable SCP recovery from biogas methane produced from waste (low methane content), the methanotrophic bioreactors need to be optimized to maintain productivity and enable economic viability, which can be achieved by improving the mass-transfer rate of biogas methane and incorporating proper biogas pretreatment. We will provide a sustainable and economically viable solution through this project.
What stage on the “Stairway of Research” contribution to problem solving
The project consists of two phases: a mini pilot-scale system demonstration in Phase I and a large-scale demonstration in Phase II. The project is currently in Phase I to assess technical and economic feasibility by operating a mini pilot-scale system..
Project Dates
Phase I (18-moth): June 2022 - December 2023
Phase II: TBD
Stage of Work
What has been accomplished so far within the project
We have organized a project team with experts in various fields (academia, industry, engineering, healthcare, consulting, etc.), enabling multidisciplinary tasks such as optimization of process trains, assessments of implementability, and economic feasibility. To search for potential feed biogas for our initial demonstration and later scale-up, we equipped proper biogas sampling tools and a portable biogas analyzer and acquired biogas characteristics from> 10 locations, including landfills and anaerobic digesters, in Bangladesh. Technical team members have designed incubation systems for inoculation and a methanotrophic bioreactor with industry experts (Calysta) and a laboratory safety manager (Stanford) to deliver a safe and efficient system. Technical team members have also designed an experimental schedule to produce a sufficient amount of SCP for a fish feed trial.
What we are focusing on now
We are now focusing on laboratory set-up at icddr,b to enable cell incubation and a pilot-scale demonstration.
People
Primary Contact: Chungheon Shin
Stanford University
. Stephen Luby: PI (Professor of Medicine): Overall project supervisor
. Craig Criddle: Co-PI (Professor, Civil and Environmental Engineering): Technical development supervisor
. Chungheon Shin: (Director of Research, Codiga Resource Recovery Center, Stanford): Technical Development Lead
. Xinyu (Cici) Teng: (MS Student, Civil and Environmental Engineering): Graduate Student Researcher
International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b)
. Mahbub Rahman, PI (Project Coordinator): Overall project supervisor
. JSM Mahedi (Senior Research Officer): Technical development engineer
. Rubaiyath Sarwar (Managing Director): Program coordinator
. Lori Giver (Chief Science and Sustainability Officer): Overall technical advisor
. Allan LeBlanc (Vice President, Aquaculture Lead): Fish trial technical advisor
. Yelena Stegantseva (Director of Fermentation): Bioprocess advisor
Funding
Methane Emissions: Conversion of Biogas from Organic Wastes into a High-Value Fish Food Supplement for Aquaculture in Bangladesh
Objective
To understand the roles that methane consuming bacteria can play in mitigating climate change and support aquaculture to increase high quality protein available at low cost.
Rationale
We are currently facing the challenges of mitigating climate change and providing access to high quality food to a growing global population—while current food production systems contribute to greenhouse gas emissions and deforestation. Methane consuming bacteria have the potential to contribute to tackling both these challenges: they consume methane as their primary source of energy and carbon, and the resulting biomass is high in protein content and can serve as a replacement for unsustainably harvested fishmeal currently used in animal feeds. These bacteria, abundant in natural environments, can be grown in dense cultures that require low land footprint for high rates of production. In this project, we are studying the role that methane consuming bacteria play in aquaculture ponds and opportunities for reducing methane emissions from aquaculture ponds. This portion of the project is in collaboration with Bangladesh Agricultural University in Mymensingh. Additionally, we are modeling ways in which commercial production of methane consuming bacteria can be deployed in the United States, using currently stranded sources of methane that would otherwise be directly emitted or flared.
Project Dates
Summer 2015 - present
Stage of Work
We have collected environmental samples from aquaculture ponds in Bangladesh, and are in the process of analyzing the abundance of methane oxidizing genes present. We are also in the process of constructing a techno-economic model using methane sources in the United States such as wastewater treatment plants, landfills and natural gas facilities.
To Learn More About This Work
Mitigating Greenhouse Gas Emissions from Aquaculture (Sahar El Abbadi)
People
Primary Contact: Sahar El Abbadi
Stanford University
. Craig Criddle, Professor of Civil and Environmental Engineering
. Stephen Luby, Professor of Medicine
. Adam Brandt, Associate Professor of Energy Resources Engineering; PI, NGI Grant
. Dr. Evan Sherwin, Post-doctoral researcher, Department of Energy Resources Engineering; collaborator on modeling
. Sahar El Abbadi, PhD student, Civil and Environmental Engineering
Bangladesh Agricultural University (BAU)
. Dr. Kaniz Fatema, collaborator on field work
Funding
Stanford Office of International Affairs
Additional Information: Mitigating Methane Emissions from Aquaculture in Bangladesh
Sahar El Abbadi, Civil and Environmental Engineering
Center for South Asia Graduate Summer Research Fellowship (2019)
Mitigating Methane Emissions from Aquaculture in Bangladesh
I was awarded the Center for South Asia Research Fellowship to pilot new research that is part of my PhD dissertation on production of greenhouse gases from aquaculture ponds. Aquaculture is an important source of protein, micronutrients and income in Bangladesh, and a rapidly growing food sector worldwide. Despite these many advantages, aquaculture ponds are a source of methane, a potent greenhouse gas. Yet in many natural environments, bacteria can mitigate methane emissions by transforming it into cell biomass—which is then transferred up the food chain to zooplankton and, eventually, fish. In fact, fish have been shown to play an important role in regulating the overall abundance of methane-consuming bacteria in natural environments, such as lakes. My research aims to understand how our current understand of natural environments translates to aquaculture ponds. Specifically, how farming different combinations of fish can impact overall pond methane emissions by regulating the abundance of methane-consuming bacteria.
The goal of my trip to Bangladesh this summer was to connect with my partners at Bangladesh Agricultural University (BAU), develop and test assays for monitoring our aquaculture experiments at BAU and collect samples to be shipped back to Stanford for preliminary molecular analysis of the abundance of methane-consuming bacteria, which establishes a baseline for field future experiments. My partners at BAU are Dr. Md Abdul Wahab and Dr Mst Kaniz Fatema, experts in aquaculture pond ecology and aquaculture feed and management, respectively.
During the first half of the summer, I worked at Stanford to prepare for field research in Bangladesh that occurred during the second half of the summer. Preparations included developing and testing our molecular assay for detecting the presence of key genes associated with the biological transformation of methane by bacteria. This work contributed to the summer research project of a visiting undergraduate student from Spelmann College, a historically black all-women’s college in Atlanta, Georgia. Before my visit to Bangladesh, we were able to test the assay on water samples collected from San Francisquito Creek on Stanford Campus, and detect the presence of methane-consuming bacteria.
I traveled to Bangladesh in mid-August, and spent nearly three weeks in Mymensingh at BAU’s campus. While at BAU, I worked on developing our methods to be used for planned field experiments. This included: touring laboratory and field facilities, developing protocols for collecting bacterial samples from aquaculture ponds, training BAU Master’s level students in sample processing best practices for subsequent molecular analysis, and learning from BAU students and staff the procedures for collecting zooplankton, phytoplankton and benthos samples.
Furthermore, we tested our procedures by collecting samples from four different aquaculture ponds: 3 ponds on a commercial aquaculture farm and 1 pond in the BAU Aquaculture Field Laboratory. At each of these 4 ponds, we collected triplicate samples at the surface, middle and bottom layers of the water column for analysis of the bacterial community and abundance of genes associated with consumption of methane. We also collected and filtered 15 L of water for quantifying plankton abundance, and qualitatively assessed the benthic community in each pond. After working with the BAU students on sample processing, I extracted the DNA from our 43 samples (36 environmental samples + experimental controls) which are to be shipped back to Stanford for molecular analysis. Finally, in addition to method development and sample collection, I presented my PhD research for BAU students in the Community Fisheries Management class, as well as for employees at World Fish in Dhaka.