The project aims at developing economically viable and socio-culturally accepted composting technologies and practices to be applied in the regional capital of Accra, Ghana. Organic fractions of municipal solid waste will be transformed into hygienically safe fertilizers of high quality as well as nutritionally rich feed components. For this purpose, larvae of the Black Soldier Fly (BSF) species Hermetia illucens and/or biochar produced from saw dust will be used. This research will contribute to income generation, poverty reduction, improvement of sanitation and soil fertility and will help closing the nutrient cycle loop. In addition, the availability of feed and fertilizers will increase rural and suburban small holders’ food and fish production and contribute to close local and national protein gaps.
The proposed project consists of four sub projects. Sub project 1 (SP1) aims at technological development, production and designing of guidelines for BSF-biochar composting of MSW, and development of BSF larvae. The study is to be carried out within the framework of a PhD study at the University of Ghana, Legon. Experiments will be done at the Biotechnology and Nuclear Agriculture Research Institute (BNARI) and analysis will be done at the University of Ghana Ecological Laboratory and CSIR-Food Research Institute in Accra, Ghana. Sub project 2 (SP2) aims at assessing the impact of the use of BSF-biochar based compost on crop productivity and the environment. The study is to be carried out within the framework of a PhD study at the University of Ghana, Legon. Experiments and laboratory analysis will be done at the University of Ghana Ecological Laboratory Accra, Ghana except the analysis of the GHG emissions, which will be done in Switzerland. Sub project 3 (SP3) aims at assessing the effect of the use of BSF-meal in aquaculture and fish quality. SP3 will be carried out by a master student from the University of Ghana, Legon. Experiments will be done at the Centre for Scientific and Industrial Research, Water Research Institute (WRICSIR), and laboratory analysis will be done at CSIR-Food Research Institute Accra, Ghana.
Sub project 4 (SP4) will be carried out by master students from the University of Ghana, Legon.
SP1: Phd study 1 Technological development, production and design guidelines
Research hypotheses (SP1):
- The given environmental and climatic factors will enable the establishment of a stable BSF-colony, which guarantees to produce continuous amounts of sufficient inoculum material for the composting technique.
- Composting materials from the waste stream of the Accra sub-urban area will prove suitable for the decomposition by BSF-larvae with respect to energy- carbohydrateand raw-fiber-content.
- Trials on the use of biochar will positively influence the binding of ammonia and potentially abundant heavy metals without negative influences on the activity of the BSF-larvae and will affect the biology, activity and concentration of BSF larvae, microbial biomass and respiration
- Composting of the organic fraction of municipal solid waste using BSF-larvae and/or biochar reduces the time to reach maturity, produces compost-fertilizer high in nutrient content (N, P, K), low in pathogens (Helminth eggs , faecal coliforms, E. coli, Salmonella, Vibrio, Campylobacter and Clostridium) and heavy metals and leads to a reasonable output of larvae biomass.
- Simple methods to produce a storable raw material (dried larvae, or granulated/ milled larvae) can be developed. Processing, packaging, storage facilities will not interfere with the quality of BSF meal regarding hygienic and nutritional aspects (pathogens and nutritional content).
Main Objective (SP1) [Outcome 1]
To establish BSF stable colony and develop production procedures and design guidelines for producing BSF-biochar based compost and BSF-meal.
Outcome 1: Composting techniques using BSF and biochar lead to accelerated composting processes, improved compost quality at lower production costs.
Specific objectives of SP1 are
- to establish a stable colony by developing the needed production infra-structure and exam ining the local life history influencing factors for mating, egg production and development of the BSF,
- to determine the effect of composting materials and temperature on the biology, activity and concentration of BSF larvae, microbial biomass and respiration,
- to develop an operational procedures and design guideline for composting municipal waste using biochar from saw dust and/or the larvae of the BSF as ecological engineers,
- to reduce the composting period and produce good quality compost (high nutrients, low heavy metals and pathogens),
- to produce larvae biomass for feeding purposes free of contamination (pathogens, heavy metals), and
- to develop, produce, and package a storable BSF-raw-product for the use in aquaculture feeds.
Expected outputs (SP1) [Output 1]
- Output 1.1: A robust BSF colony with high egg laying performance for research purposes is established.
- Output 1.2: Strategies are developed for managing Hermetia (BSF) flies and compost
heaps; an operational compost guide is available.
SP2: PhD study 2 Agriculture and Environmental impact studies
Research hypotheses (SP2)
- Composting of MSW with BSF larvae and biochar from sawdust will reduce greenhouse gas (methane, nitrogen and carbon dioxide) emission and leachate amounts and concentration.
- The biochar in BSF-biochar based compost will increase soil affinity for heavy metal sorption, and its continuous use in farming will not lead to transformation and accumulation of heavy metals in food crops.
- Continuous application of BSF-biochar based compost to soil will increase soil organic carbon storage and quality, nutrient availability, recovery and use efficiency as well crop yield (economic and biomass).
Main Objective (SP2) [Outcome 2]
To investigate the impact of the use of BSF-biochar based compost in agriculture and on the environment.
Specific objectives of SP2 are
- to assess the effect of BSF- composting technology on greenhouse gas (CH4, N2, CO2) and leachate production and concentration,
- to assess the effect BSF-biochar based compost on heavy metal sorption, transformation and accumulation in the soil and food crops (4 season cropping in 2 years), and
- to assess the effect of the use of BSF-biochar based compost on soil organic carbon storage and quality, nitrogen dynamics (N-mineralization, recovery, synchrony and leaching) and crop yield (economic and biomass).
Expected outputs (SP2) [Outputs 2]
- Output 2.1: Greenhouse gas emissions are assessed.
- Output 2.2: Strategies to avoid risks and to use the benefits of the products are provided
- Output 2.3: The effect of BSF compost -fertilizer on crop yield and soil fertility is known
SP3: MSc 1: Aquaculture study
Research hypotheses (SP3):
- By blending the BSF meal with other available agricultural by-products (e. g. rice and maze-bran) a basis for aquaculture feed is found to feed to fish on a semi-intensive level.
- Growth performance of the fish will positively be influenced compared to pure vegetable diets.
Main Objective (SP3) [Outcome 3]
A BSF-larvae product is developed for use in fish-feeds.
Specific objectives of SP3 are
- to demonstrate the possibility to manufacture compound feeds on industrial and home-made level with the inclusion of BSF-meals (energy content of more than 15 MJ/kg and about 30 % crude protein), and
- to test the effect of BSF fish meal on the performance and quality of fish produce in order to prove its suitability for semi-intensive fish production.
Expected output (SP3) [Outputs 3]
- Output 3.1: Technology for producing BSF-larvae fish-feed is elaborated
- Output 3.2: Recipe for producing fish-feed based on BSF larvae is available.
SP4: MSc 2 : Socio-cultural and economic studies
Research hypotheses (SP4)
- BSF meal will be a cost effective substitute to the conventional high-cost fishmeal.
- The techniques of producing BSF-biochar based fertilizer and BSF fish-meal are socio-culturally acceptable to small holder farmers in Ghana.
- Farmers have a positive attitude toward the use of BSF-based fertilizer and fish meal as well as in the consumption of food and fish from these products.
Main objective (SP4) [Outcome 4]
To determine economic feasibility, farmers perception and willingness to use BSFcomposting and insect-meal production technologies. Economic feasibility is proved and benefits recognized among stakeholders and on policy level.
Specific objective of SP4 are
- to understand and assess the economic relevance of BSF- composting, and insectmeal production from the organic fraction of municipal solid waste,
- to determine farmers acceptance of BSF- composting and insect-meal production technologies.
Expected output (SP4) [Outputs 4]
- Study on economic feasibility of BSF composting
- Negative and positive attitudes of farmers towards production, use of compost and feeds are determined.
- Stakeholders and policy makers are involved in the research and informed on the results