Large-scale eco-friendly recycling of municipal solid waste

Burundi is a landlocked country in East Africa, among the least developed countries globally, with 80% of its population living in poverty. Agriculture employs about 90% of the population and contributes about 40% to the country's GDP (World Bank, 2021), and according to the recent census of the Burundian Ministry of National Solidarity, Social Affairs, Human Rights and Gender « there are still many people living in straw houses ».

The population of Burundi is estimated at 12.55 million inhabitants - 50.8% female and 49.2% male- (World Bank, 2021).

However, Burundi is facing significant challenges in managing its waste, which is contributing to environmental degradation, greenhouse gas emissions, and negative health impacts for its citizens.

Bujumbura is the economic capital of Burundi. Approximately 85% of waste produced in Bujumbura city is biodegradable with a high moisture content (most of it is food waste, then garden and paper), 10% is plastic and 5% is made of glasses, wood, metals, and other materials. More than 50% of municipal solid waste (MSW) in Bujumbura comes from households, then hotels & restaurants, public markets, street, etc. 

MSW management is a major challenge in many cities in developing countries, including Bujumbura City. According to a study by the Ministry of Environment, Agriculture and Livestock, Bujumbura generates over 600 tons of waste per day, with less than 50% of it collected and transported to landfills or dumpsites (MENAGRI, 2021). This has resulted in the accumulation of waste in public spaces, waterways, and residential areas, posing significant health and environmental risks.

The improper management of MSW in Burundi has significant social and economic impacts. For instance, the burning of crop residues (common waste management practice) contributes to soil degradation, reducing the productivity of the land and exacerbating food insecurity. Moreover, the inefficient use of waste means that valuable resources that could contribute to soil fertility and crop production are being wasted, reducing the income potential of farmers. 

Women and youth are the most vulnerable groups affected by the negative impacts of MSW management. Women are often responsible for managing household waste and are more likely to be exposed to the negative health impacts of poor waste management (UN Women, 2020). Youth face significant challenges in accessing employment opportunities in the agricultural sector, the largest employer in the country (UNDP, 2020).

Furthermore, climate change has been exacerbating environmental problems, including waste management, in the country. The waste generated by households has been increasing rapidly, with an estimated 80% of the waste going to landfills, which are poorly managed, leading to severe pollution of air, soil, and water. 

Recycling is an effective way of mitigating the problem of MSW. Recycling involves converting waste materials into new products, reducing the amount of waste that goes into landfills and minimizing the environmental impact of waste disposal. According to the United Nations Environment Programme, recycling can reduce greenhouse gas emissions by up to 15%, decrease the pressure on natural resources, and contribute to the creation of jobs and economic growth (UNEP, 2018).

The question we asked ourselves is "How to develop agriculture and raise the habitat of the basic farmer while preserving the environment? ".

This is how we developed an aerobic composter capable of gradually separating biodegradable waste from plastic waste while producing compost within 30 days.

At the end of this process, which avoids the production of greenhouse gases, particularly methane (CH4) and carbon dioxide (CO2) normally produced during the anaerobic decomposition of waste, as is the case at the uncontrolled open dumpsites, we produce compost useful for biological fertilization of soil and plastic pellets which will be used for the manufacture of ecological building materials.

To promote circular agriculture and valorization approaches in Burundi, CITY-FARM has developed 2-processes that aims to turn uncontrolled waste dumpsites in Bujumbura city into temporary treatment centers.

Organic waste recovery unit:

This unit is based on the aerobic composter, capable of spanning, turning, aerating, and reducing the windrows of organic waste. This aerobic composter, locally made, makes large-scale aerobic composting possible of organic waste.

The windrows of mature compost are then covered by a protective tarpaulin while awaiting distribution to the farmers. A part of the mature compost is set aside to be enriched with urea for use in degraded agricultural landscapes. The distribution of compost to farmers prevents the eutrophication of rivers near the dumpsites and Lake Tanganyika.

Aerobic composting as developed by CITY-FARM offers three (3) direct major implications:

• A capacity to process large quantities of MSW.
• Sequestration of greenhouse gases, particularly CO2 & CH4 emitted during the anaerobic decomposition of piled up organic waste.
• Production of compost equivalent to one tenth of the quantities of organic waste treated. This compost is an alternative to the use of chemical fertilizer.

Plastic waste recovery unit:

Plastics are another component of MSW in Bujumbura City. Different plastic types require different recycling methods, including sorting, shredding, and melting. Recycling plastic reduces the need for virgin plastic production, which saves energy and reduces greenhouse gas emissions.

CITY-FARM has validated an economic and ecological solution which consists of blocking plastic pellets recycled by inserting it into long-life materials, such as those used for the construction of buildings (brick, paving stones, tile etc.) twice as resistant as fired bricks or cement-based pavers and classic tiles.

Below are the broader socio-economic objectives of our plastic recovery unit:

• Reduce waste and provide affordable housing for low-income families and communities in Burundi.
• Contribute to safe, affordable, and climate-resilient housing options to vulnerable communities in Burundi currently living in sub-decent houses and or straw houses.
• Sustainable production and consumption patterns.
• Creation of sustainable green jobs. 

The mechanized processing technology and composting techniques employed by CITY-FARM aim to address the challenges associated with inefficient waste management, such as environmental degradation, greenhouse gas emissions, and negative health impacts, by creating value from the waste through the production of organic fertilizer and plastic pellets for later upgrading to ecological building materials.

1. Our waste recycling solution serves the community living around the open dump located in the Buterere district in the city of Bujumbura.

The community around the Buterere dump lives in extreme precariousness (health and financial). The process developed by CITY-FARM will lead to:

• transform the dump into a transitional center before the return to the market, thus creating green and sustainable jobs which will be occupied by the current operators of the dump who are mainly women and girls.
• improve the living conditions of vulnerable people living around Buterere district.

2. The solution is profitable for the basic farmers grouped in cooperatives:   

• the production of large quantities of ecological compost will allow biofertilization of nearly 1000 ha of fields per year.                                                                                                                                                                               

3. For the communities living in straw houses (i.e. 30% of the Burundian population) who, due to a lack of decent housing with all kinds of bad weather that entails, do not get down to development activities (the risks are enormous, especially children who are often exposed to various diseases):

• with the daily production of plastic waste, i.e. 60 tons per day, it is possible to recycle them and manufacture 75,000 tiles, rafters and plastic-sand boards that can cover 150 houses.

4. For rural communities, often underserved, who find themselves farming in protected basins due to their degraded agricultural land:

• the availability of organic fertilizer and enriched organic fertilizer will improve soil structure, increase water-holding capacity, and enhance nutrient availability, leading to higher crop yields. 

5. For the city of Bujumbura:

• by improving the sanitation of the city and eliminating the consequences of non-treatment of waste on the uncontrolled dump site
• the Aerobic recycling of biodegradable household waste from the Buterere dump will mitigate the phenomena of heat islands and global warming in general. 

6. Job creation and economic development: 

• the innovation proposed by the CITY-FARM company can create income-generating opportunities for farmers, particularly women and youth, by generating value from MSW. 

According to the World Bank, the agricultural sector employs more than 80% of the Burundian population, and promoting sustainable agriculture can contribute to reducing poverty and increasing food security.

7. The solution is profitable for Burundi and neighboring countries:

The agriculture sector in Burundi accounts for about 32% of greenhouse gas emissions, mainly from the use of synthetic fertilizers, crop residue burning, and animal waste. The emissions are primarily in the form of CO2eq, which contributes to climate change (World Bank, 2019).

The efficient transformation of waste (sorting, collecting and recovery) into a useful resource has a positive impact on :

• improving the resilience of agroecosystems and populations through better capacity to implement adaptation to climate change;
• the mitigation of climate risks through the sustainable management of landscapes through the rehabilitation of lands and shepherds of degraded rivers.

CITY-FARM LLC is a company that has a private operating regime within the framework of social entrepreneurship.  It is headed by a general manager who reports to the partner's board of directors. Its activities, focused on the recycling of municipal solid waste, demonstrate a real commitment to finding a local solution to local problems through an ecosystem approach.

CITY-FARM is a model of green circular economy. Municipal solid waste is the raw material, and its recycling allows the return of recycled products to the market while providing a positive environmental impact (particularly the return of organic matter to the soil, and therefore of carbon).

The ecosystem approach used by CITY-FARM has the particularity of addressing approximately 95% of MSW, including waste from households, hotels, restaurants, school canteens, markets etc. (whereas  approximately 5% of the remaining waste is made up of glasses, metals, and other materials).

The MSW treatment model developed by CITY-FARM is transversal to the objectives of sustainable development. Currently the company's efforts are focused on:

• An organic waste recovery unit to transform it into compost and
• The crushing of plastic waste into granules for later upgrading to ecological building materials.

With more than two years of action research on the recycling of MSW with a view to the production of aerobic organic fertilizer and plastic granules for the purpose of manufacturing ecological building materials, CITY-FARM is equipped with a know-how to scale the project. The tests carried out during the experimental period of the approach were conclusive. 

The research department of our company has developed a machine having a mechanism capable of gradually recovering plastic waste from biodegradable waste, while changing the anaerobic degradation reaction of biodegradable waste into an aerobic degradation reaction.

This mechanism makes it possible to address the large-scale recycling of MSW in its majority, thus making it possible to transform MSW into a sustainable development solution.

Focusing on innovation and efficient waste processing, we have forged collaborative partnerships with local NGOs working to find answers to the challenges of poverty, hunger and social injustice. This is how we have a partnership with the NGO Empowering Response Burundi (ERB – Autonomiser la Réponse Burundi (erbdi.org) ) because of its close collaboration with small farmers for 20 years. 

We have already recycled nearly 6,000 tons of waste from households in the Kinindo area in Bujumbura town hall, resulting in a production of 600 tons of compost. We have already served a hundred families of farmers with agricultural areas of a third of a hectare at the rate of 6 tons of compost for a third of a hectare.

With approximately 600 tons of MSW produced per day in the city of Bujumbura, the challenge is daunting: the possibility of producing 50 tons of compost per day and plastic pellets for later upgrading into ecological building materials. 

The aerobic degradation of the 600 tons of MSW produced per day would allow:

•  fertilization of 1092 hectares per year and
• manufacture 75,000 tiles, rafters and plastic-sand boards that can cover 150 houses per year .

We are a company with ambitions to recycle 95% of MSW produced in Bujumbura city (waste from households, hotels, restaurants, school canteens, public markets, etc.), i.e. 570 tons of waste per day (5% of household waste remaining produced daily in the city of are glasses, metals and others).

We produce ecological compost and are equipped with a technique and know-how to produce 50 tons of compost per day, i.e. an amendment, a fertilizer and a fertilizer for 1000 hectares per year.

We want to:

• invest in infrastructure, including recycling facilities, to ensure that there are adequate facilities to process the recyclable materials collected. This can help to reduce the accumulation of waste and ensure the success of the recycle project

• restore our degraded agricultural soils

• promote waste for food security

• help restore soil fertility and improve water retention and nutrient supply to plants

• do our part by reducing greenhouse gas emissions that contribute to climate change

• increase the production and productivity of small farmers

• conduct educational campaigns to raise awareness about recycling among the burundian population. The campaigns can be conducted through various mediums such as radio, television, and social media

• educate our co-citizens on the impacts of non-waste, the return of organic matter to the soil, the natural carbon cycle, urea in our fields

• show solidarity and build a link between the urban environment and unserved rural communities

We have used our own funds to research, design, develop the innovative method of transforming anaerobic decomposition into aerobic transformation, separating biodegradable waste from plastic waste while producing mature and enriched compost on a large scale.

We need help from Solve to:

• Access leadership coaching and strategic advice from experts in the recycle industry.
• Gain knowledge from impact-minded leaders of carbon emission.
• Access to funding in the form of grants and investments to scale our project, reach and help more small farmers.

We produce plastic pellets for later upgrading to ecological building materials intended primarily for rural populations without decent housing in order to offer them the possibility of building low-carbon housing that is also adaptable to increasingly extreme weather conditions.

To continue in this step towards sustainable development, we need help from Solve to:

• Access to funding in the form of grants and investments to scale our project, reach and help more vulnerable communities in Burundi currently living in sub-decent houses and or straw houses. 
• Join powerful network offering inspiration and guidance
• Access leadership coaching and strategic advice from experts in the plastic recycle industry.
• Gain knowledge from impact-minded leaders of carbon emission.

We appreciate your time and guidance and hope a for a favorable feedback from you. 

To promote circular agriculture and valorization approaches in Burundi, CITY-FARM has developed 2-processes that aims to turn waste dumps into temporary treatment centers. As approximately 85% of waste produced in Bujumbura city is biodegradable with a high moisture content and 10% is made of plastic, CITY-FARM has developped a mechanized processing technology system to recycle 95% of municipal solid waste produced in Bujumbura city.

Waste management through recycling is not really an innovation because it is already practiced in several countries. However, it is not common in most developing countries where sorting and recycling is initiated individually (especially women, children and the poor). The advantage of this proposal is that it aims to organize the waste sorting and recycling sector. The proposed solution adopts an integrated approach including social, commercial and scientific aspects.

In Burundi, the existing practice for managing agricultural waste is primarily through burning and dumping in uncontrolled landfills. Therefore, the improved method by CITYFARM company  is not competing against an existing technology or product, but rather proposing a new approach to managing municipal solid waste that complements circular agriculture and valorization approaches. 

The innovation of the CITY-FARM company is related to

1.) the transformation of the anaerobic degradation reaction of municipal solid waste piled up in an open dump into an aerobic degradation reaction 

2.) the technology used for the treatment of organic waste relying on the aerobic composter (locally made)

3.) the large-scale aerobic composting, which allows the sequestration of greenhouse gases, particularly methane and carbon dioxide emitted during the anaerobic decomposition of organic waste piled up in uncontrolled dumps

4.) the practice of sustainable waste management. 

We want to change the history of vulnerable communities in Burundi currently living in sub-decent houses and or straw houses by :

• providing ecological building materials mainly made of recycled plastic for them to construct safe, affordable, low-carbon and climate-resilient housing.

The mechanized processing technology and composting techniques employed by CITY-FARM aim to address the challenges associated with inefficient waste management, such as environmental degradation, greenhouse gas emissions, and negative health impacts, by creating value from the waste through the production of organic fertilizer and low-carbon emission and climate-resilient building materials.

The solution proposed by the CITY-FARM company is closely linked to sustainability, as it addresses various environmental, social, and economic challenges associated with inefficient municipal solid waste management.

Our goals for the next year :

1. Efficient and sustainable process at every level of MSW management:

Collecting MSW :

• Partnership with garbage truck owners so that more waste is brought to our treatment site (this is to prevent waste from being found on the street or being incinerated in neighborhoods as is the case Right now)
• Invite the Ministry of the Environment, Agriculture and Livestock to raise citizens' awareness of the harmful effects of incinerating waste in their gardens.

Sorting MSW :

• Train more stuff at this crucial level of waste management
• Awareness programs especially for domestic workers and those in hotels and restaurants on how to sort waste at source.

Treatment of MSW :

• Reduce the accumulation of waste and ensure the success of the recycle project
• Invest in infrastructure, including recycling facilities, to ensure that there are adequate facilities to process the recyclable materials collected

2. Create interest among the community

• through NGO's, farmer cooperatives, etc.
• manufacture trash containers made of recycled plastic 
• attract potential customers, showing how recycling is creating an impact our locality and contributing to sustainable living.

3. Marketing and sales of recycled products

• The recycled products will be marketed and sold to create a market for them.

Our goals in the next 5 years :

1. Implementation of efficient and sustainable processes for ecological building materials using recycled plastic

• access to adequate funding
• invest in the necessary infrastructure and machinery
• create more jobs, especially among women and youth
• train staff on the safe handling of machinery
• Gain exposure in the media
• partnership with local companies and neighboring countries specialized in construction, particularly for the flow of materials.

2. Scale education on recycled materials

• through school programs
• through various mediums such as radio, television, and social media
• popularize the use of urine as fertilizer in agricultural fields.

3. Establish a strong brand identity

• using clients stories through our website and various social media
• show how the company is reducing landfills to conserve natural resources and save our environment and the planet.

4. Continuously involved in Research and Development in MSW management industry:

•  incorporate new ideas
• incorporate creative solutions and innovative thinking into our already established systems and processes. 

This project aims to establish a recycling program for MSW in Bujumbura to promote a circular economy, address the challenges related to waste management, and mitigate climate change. The program will also promote gender equality by providing employment opportunities for women and youth, and improving public health by reducing exposure to harmful waste materials. This proposal aligns with the United Nations Sustainable Development Goals (SDGs) 3, 5, 12, 13, and 15, which aim to ensure healthy lives, promote gender equality, ensure sustainable consumption and production patterns, take urgent action to combat climate change, and protect life on land.

General data: The basis for calculating MSW in developing countries is 600g per day and per inhabitant and the city of Bujumbura has around 1,100,000 inhabitants. The quantity of MSW is estimated at 660 tons of waste per day, 85% of which is biodegradable waste (BW) and 10% is plastic waste.

• Statement of the basis of calculation for CO2 and CH4 avoided: 

The calculations are based on 600 tons, the total weight of BW generated per day in Bujumbura corresponding to the quantity of total solids + water capital.

The weight of total solids represents 20% of the total weight of BW available, i.e.: 600 tons × 20/100 = 120 tons per day.

The weight of volatile solids represents 80% of the weight of total solids, i.e.: 120 tons × 80/100 = 96 tons per day.

The calculation basis for biogas is 0.67 m3 for 1 kg of volatile solids, corresponding to this:

96000 kg × 0.67 = 64320 m3 of biogas

40% of which is carbon dioxide and 60% methane.

The 40% of carbon dioxide corresponds to 64320 × 40/100 = 25728 m3 of CO2.

The 60% of methane corresponds to 64320 × 60/100 = 38592 m3 of CH4.

Considering that CH4 is 28 times more powerful than CO2, the 38592 m3 of CH4 correspond to 38592 × 28=1080576 m3 CO2 equivalent. In total, the anaerobic degradation of MSW in Bujumbura produces:

1080576 + 25728 = 1,106,304 m3 CO2 equivalent per day

i.e. 402,694,656 m3 of CO2 equivalent per year

Considering that the mass of CO2 is 1.964kg/ m3 of CO2, 402,694,656 m3 of CO2 correspond to 790,892.304384 tons equivalent of CO2 equivalent per year.

• Statement of the basis of calculation for compost

Compost from recycling is 10%, or 600 tons ×10/100 = 60 tons of potential compost per day.

That is 21,840 tons of potential compost per year.

• Statement of the basis of calculation for soil fertilization

Considering that a quantity of about 20 tons of compost per hectare is sufficient for good soil fertilization. The number of hectares of farms that can be fertilized by the amount of potential compost produced annually by the CITY-FARM company corresponds to:

1ha ×21,840tons/20 = 1092 ha per year.

Demographic change, rural exodus and increasing urbanization create a major challenge related to waste management for Bujumbura. Urbanization has lengthened the route of waste without closing its cycle. In Bujumbura, it faces increasing quantities of MSW at a time when financial resources for urban sanitation services remain limited. The Buterere dumpsite is hardly organized. The impassability of the road leading to this dumpsite means that the trucks transporting waste are unable to deposit it in the place that has been reserved. The waste is piled up in an anarchic manner, the Gasenyi river regularly flows into the dump making hygiene more fragile. In addition, the anaerobic decomposition of organic materials contained in MSW strongly contributes to global warming, through the emission of greenhouse gas.

Land degradation, irrational use of mineral fertilizers, air pollution, soil quality, soil biodiversity and public health have revived interest in the regard to organic recycling practices such as composting. The potential offered by large-scale aerobic composting makes it possible to transform MSW into resources for agricultural operations. This proposal is very interesting because it has an interest linked to the improvement of soil fertility and quality, thus causing an increase in agricultural productivity, allows for better soil biodiversity, reduced ecological risks and a more favorable environment for many farmers.

However, burundian's farmers are unable to use these potentialities because large-scale systems require substantial investments, great knowledge and skills in monitoring the process.

Considering this problem of landfill management and the development of urban organic waste through recycling, the biodegradable waste recovery unit will apply the Lavoisier principle: "Nothing is lost, nothing is created, everything is transformed”. It proposes a solution which will come to close the cycle opened by the incapacity of the Municipal services, a large scale which insists on the importance of a process of fast aerobic composting suitable for large urban recycling centers.

Nevertheless, the supply of raw material for the manufacture of aerobic compost provides at the same time other non-biodegradable materials. Dumping them into nature would be contrary to our vision. These wastes consist of plastics (10% of MSW). They pose a problem of insalubrity and visual pollution for the environment when they are produced massively for single-use uses. Considered then as waste, they are thrown into landfills, often poorly controlled, where they pollute.

With a view to reducing this pollution, taking into account the solutions that our consumer society model offers us, the CITY-FARM plastic waste recovery unit has validated an economical and ecological which consists in blocking plastic waste by inserting it in long-life materials, such as those used for the construction of buildings.

This technique is good to apply to successfully achieve the objective of improving the habitat of the Burundian population. Indeed, on the one hand we have thousands of families currently living in straw houses; on the other hand, the demographic projection foresees more people living in urban areas than in rural areas in 2030 and the cost of conventional construction is only going to climb!

Our solution is leveraging traditional, ancestral and natural technologies, and knowledge systems. 

Our municipal solid waste recycling program also aims to reduce existing gender inequalities, as the current operators of the Buterere open dump are predominantly women and girls, resulting in unique threats.

We aspire to create jobs and income for small urban and peri-urban producers and more specifically disadvantaged groups such as women and young people organized in Producer Associations, who will in fact become "partners" or guarantors of proper execution of activities.

Women are often sidelined by Burundian society. We will provide education and training on reproductive health and family planning. Most of the time, girls are taken out of school too early, they are vulnerable to sexual violence and coerced sex, and subjected to harmful practices. They are confronted with pregnancies before reaching the physical, emotional, and social maturity necessary to become mothers.

The general manager and shareholder is a woman and the majority of the sorters are women.

As said in our introduction : 

• Burundi is a landlocked country in East Africa, it is among the least developed countries globally, with 80% of its population living in poverty. The heart of the national economy is agriculture (most of the poor population lives in rural areas and agriculture is their main source of income), and according to the recent census of the Burundian Ministry of National Solidarity, Social Affairs, Human Rights and Gender « there are still many people living in straw houses ».

• The population of Burundi is estimated at 12.5 million inhabitants (50.8% female and 49.2% male) in 2021 according to Word Bank with an estimated annual growth rate of 2.4%.  

• Agriculture employs about 90% of the population and contributes about 40% to the country's GDP (World Bank, 2021). However, Burundi is facing significant challenges in managing its waste, which is contributing to environmental degradation, greenhouse gas emissions, and negative health impacts for its citizens.

• Women and youth are among the most vulnerable groups affected by the negative impacts of waste management. Women are often responsible for managing household waste, including agricultural waste, and are more likely to be exposed to the negative health impacts of poor waste management (UN Women, 2020). Youth, on the other hand, face significant challenges in accessing employment opportunities in the agricultural sector, the largest employer in the country (UNDP, 2020).

Our large-scale aerobic composting makes it possible to transform municipal solid waste into resources for agricultural operations. Our solution is very interesting because it has an interest linked to the improvement of soil fertility and quality, thus causing an increase in agricultural productivity. In addition, our proposal allows for better soil biodiversity, reduced ecological risks and a more favorable environment for many farmers.

CITY-FARM is a model of green circular economy. Household waste is the raw material, and its recycling allows the return of recycled products to the market while providing a positive environmental impact (particularly the return of organic matter to the soil, and therefore of carbon).

We produce plastic pellets for later upgrading to ecological building materials intended primarily for urban populations without decent housing in order to offer them the possibility of building low-carbon housing that is also adaptable to increasingly extreme weather conditions.

As we invest in infrastructure, including recycling facilities, the process developed by CITY-FARM will lead to transform the dump into a transitional center before the return to the market, thus creating green and sustainable jobs which will be occupied by the current operators of the dump who are mainly women and girls.

Our plan to become financially sustainable is to access our first donation or grant, after then, the marketing of the compost produced during the duration of the subsidy will make it possible to have working capital for the continuation of the recycling work.  

We have used our own funds to research, design, develop the innovative method of transforming anaerobic decomposition into aerobic transformation, separating biodegradable waste from plastic waste while producing mature and enriched compost on a large scale.

We have forged collaborative partnerships with local NGOs working 

closely with small farmers. It is to them that we are sell the majority of our enriched compost.