Resource Recovery & Reuse Series

This report examines social equality aspects related to resource recovery through solid waste composting and wastewater irrigation. The report shows that women are represented in greatest numbers at the base of the recycling chain, most often as informal waste pickers and as sorters of recyclables with limited access to resources and upward mobility. Despite a wide gender gap in the solid waste and sanitation sectors, women play a key role in both municipal waste reduction and food safety where irrigation water is unsafe. Analyzing the gender dimension is important for understanding household responses to recycling programs, differences between the formal and informal sectors as well as along the waste-to-resource value chain from collection to treatment and reuse. The report stresses the important role of women in household waste management, including waste segregation, and the power of women-dominated waste picker associations, where the informal sector plays an essential role alongside the formal sector.

Wastewater-fed aquaculture has a long history, especially in Asia. This report examines three empirical cases of integrated wastewater treatment and aquaculture production. From an aquaculture entrepreneur’s perspective, the combination of fish farming and wastewater treatment in common waste stabilization ponds allows significant savings on capital (pond infrastructure) and running costs (wastewater supporting fish feed). On the other hand, the treatment plant owner will have the benefit of a partner taking over plant maintenance. Given the importance of food safety and related perceptions, the report is focusing on innovative business models where the marketed fish is not in direct contact with the treated wastewater, but only the brood stock or fish feed. The financial analysis of the presented systems shows profitable options for the fish farmer, operational and in part capital cost recovery for the treatment plant, and as the treatment plant operators can stop charging households a sanitation fee, eventually a triple-win situation for both partners and the served community.

A necessary extension of the concept of Resource Recovery and Reuse with an even higher priority is the prevention and reduction of waste. One concern, in particular, is food waste, which constitutes the largest share of human waste. Target 12.3 of the United Nations Sustainable Development Goals (SDGs) is to ‘halve per capita global food waste at the retail and consumer levels and reduce food losses along production and supply chains, including post-harvest losses, by 2030’. For this report, over 400 businesses were analyzed to identify common approaches and business models to address the food waste challenge. The business models are presented under seven categories – measurement, redistribution, resell, value addition, responsible waste collection, resource recovery, and recycling – with a special focus on their application potential to the Global South.

Globally, 50% of the population relies on on-site sanitation systems (OSS) such as septic tanks and pit latrines and is, hence, in need of Fecal Sludge Management (FSM) solutions. India is a classic example, given that its government built more than 100 million toilets with the majority relying on OSS. With 400 fecal sludge treatment plants (FSTPs) in various stages of planning, procurement and construction, this report comes at an opportune time to present findings on FSM business models already implemented across India. Interviews were conducted with a total of 105 Emptying and Transport (Eamp;T) operators in 72 towns and cities across 16 states in India, 22 representatives from municipalities that own emptying vehicles, 18 FSTP operators and more than 30 institutions. In addition, procurement tenders for Eamp;T and FSTPs in 13 states were analyzed. In total, 18 business models were identified, several with energy or nutrient recovery components. The analysis of Eamp;T operators revealed clear differences that steer a business towards success or failure. The majority of operators still dispose fecal sludge in an unsafe manner, due to the lack of official disposal or treatment sites. In comparison to sewer networks, the capital and operating costs (per capita) of FSTPs were significantly lower. The report provides evidence-based discussions on policies and recommendations for scaling and sustaining FSM.

Based on primary data from fecal sludge (FS) treatment plants in three West African urban regions (Ouagadougou in Burkina Faso, Greater Accra in Ghana, and Grand Nokou in Benin), FS collection and treatment patterns were analyzed to identify possible scenarios for resource recovery (RR) through FS co-composting. FS collection was analyzed for up to 7 years, in part per day, month and season, as well as FS characteristics to understand peak flows, FS qualities and related variations to plan for appropriate RR technology and capacities. Overall, the FS volumes collected by vacuum trucks were not significantly affected by the calendar days, months or seasons. Commonly assumed increases during rainy months were, for example, only recorded in Ouagadougou. FS composition appeared highly variable with a pronounced difference in total solids between FS collected from households versus institutional sources, likely indicating that institutions are served more frequently. The analyzed treatment plants appear to be exploited beyond their capacity. RR for reuse can turn sludge disposal from a cost into a source of revenue with co-benefits for farmers and the environment, thereby reducing the pressure on tipping fees. The probability of the added co-compost production being financially viable on its own was estimated for all the study sites, indicating an earliest breakeven point after 5 to 8 years.

Over the last decade, the International Water Management Institute (IWMI) has explored the use of fecal sludge (FS) in combination with other organic waste sources to optimize FS treatment and composting for the production of a safe organic fertilizer, which can – depending on demand – be enriched with crop nutrients or pelletized for volume reduction, delayed decomposition or easier application. Based on IWMI’s experience, this training manual has been compiled for plant managers and trainers to help ensure that staff involved in FS treatment and production, and application of an FS-based co-compost adopt best practices in all processes involved. The manual can be adapted to local needs as required. It also includes information on compost registration and certification, as well as guidelines for co-compost application in the field.

Black soldier fly colonies can produce about 100 times more protein per year than chicken or soybeans, not to mention cattle, on the same area of land. The flies can directly feed on different types of organic wastes, leapfrogging closed loop processes within a circular food economy. Also, where no protein is needed, for example, to feed fish or pigs, the larvae can be processed into high-quality biodiesel. However, can this be done at scale? The answer is ‘Yes’. The report showcases some of the leading global businesses in Black Soldier Fly production.

In low- and middle-income countries, the management of fecal sludge from on-site sanitation systems has received little attention over many decades, resulting in insufficient or missing regulations to guide investments and management options. To address this gap, this report examines existing and emerging guidelines and regulations for fecal sludge management (FSM) along the sanitation service chain (user interface, containment, emptying, transport, treatment, valorization, reuse or disposal). It also draws empirical examples from guidelines across the globe to support policy-makers, planners, and sanitation and health officers, as well as consultants in low- and middle-income countries in the development and design of local and national FSM guidelines and regulations.

There is a strong link between gender and energy in view of food preparation and the acquisition of fuel, especially in rural areas. This is demonstrated in a range of case studies from East and West Africa, where biochar, human waste and other waste resources have been used to produce briquettes or biogas as additional high-quality fuel sources. The synthesis of the cases concludes that resource recovery and reuse for energy offers an alternative to conventional centralized grid projects which, while attractive to investors and large-scale enterprises, do not necessarily provide job opportunities for marginalized communities. Reusing locally available waste materials for energy production and as soil ameliorant (in the case of biochar) in small enterprises allows women and youth who lack business capital to begin modest, locally viable businesses. The case studies offer concrete examples of small-scale solutions to energy poverty that can make a significant difference to the lives of women and their communities.

To understand the full value of Resource Recovery and Reuse (RRR), a systematic assessment approach that balances complexity with practicality is required. This report highlights the methods available for quantifying and valuing social, environmental and economic costs and benefits of RRR, focusing on Cost-Benefit Analysis (CBA) as the primary framework. Rather than prescribing a standardized technique for conducting CBA for RRR, this report presents broad frameworks and several examples that can be catered to individual contexts. This results in a suggested eight-step process accompanied with suggested assessment techniques which have to be tailored to the type of question the assessment is meant to answer and related system boundaries.

The safe recovery of nutrients from our waste streams allows us to address the challenges of waste management and soil nutrient depletion conjointly. Commercialization of waste-based organic fertilizers such as FortiferTM (fecal sludge-based co-compost) has the potential to generate significant benefits for developing economies via cost recovery for the sanitation sector and the provision of an alternative agricultural input for smallholder farmers. To guide future FortiferTM businesses, this report presents examples of detailed market assessments, based on farmers’ perceptions, attitudes and willingness-to-pay (WTP) for a pelletized and non-pelletized FortiferTM co-compost. The research was conducted in the Greater Accra and Western regions in Ghana, and in and around Kampala (Uganda), Bangalore (India), Hanoi (Vietnam), and Kurunegala (Sri Lanka). Cross-country analyses helped to understand the effects of market drivers and, where possible, capture lessons learned for knowledge sharing.

Resource recovery and reuse (RRR) of domestic and agro-industrial waste has the potential to contribute to a number of financial, socioeconomic and environmental benefits. However, despite these benefits and an increasing political will, there remain significant barriers to build the required up-front capital which is discouraging private sector engagement. A systematic analysis and understanding of the enabling environment, public and private funding sources, risk-sharing mechanisms and pathways for cost recovery can help to identify opportunities to improve the viability of RRR solutions. This report looks at regulations and policies that remove disincentives for RRR, public and private funding sources for capital and operational costs, risk mitigation options through blending and structuring finance, and options for operational cost recovery.

Recovering energy from waste offers dual benefits – a) improved waste management, and b) provision of reliable energy to households, institutions and commercial entities. In this report, we present a socioeconomic assessment of three energy business models (briquette manufacturing, on-site (public toilet) energy generation, and agro-waste electricity generation) based on feasibility studies carried out in the city of Kampala, Uganda. We assess the potential economic, environmental and social impacts of waste-to-energy business models taking into consideration a life cycle of emissions to provide decision makers with the overall costs and benefits of the models to society versus a business-as-usual scenario.

Recycling and reuse of treated wastewater are an important part of the sanitation cycle and critical in an environment such as urban India with decreasing freshwater availability and increasing costs for delivering acceptable quality water, often from far distance. This report has been developed as a possible guidance document for the Indian government and gives substantial focus to the financial and economic benefits of wastewater recycling from the perspective of public spending. The report presents possible strategies for city and state planners and policymakers in view of the sanitation situation and the role of wastewater recycling in the larger cities in India (class I and II cities and towns with populations above 50,000), and focuses on recycling at the end of sewerage systems after treatment at sewage treatment plants.

Where modern heating and cooking fuels for domestic, institutional, commercial and industrial use are not readily available, briquettes made from biomass residues could contribute to the sustainable supply of energy. This study reviews the briquette making process, looking at the entire value chain starting from the type and characteristics of feedstock used for briquette making to the potential market for briquettes in developing countries. It also analyzes the role that gender plays in briquette production. Depending on the raw materials used and technologies applied during production, fuel briquettes come in different qualities and dimensions, and thus require appropriate targeting of different market segments. Key drivers of success in briquette production and marketing include ensuring consistent supply of raw materials with good energy qualities, appropriate technologies, and consistency in the quality and supply of the briquettes. Creating strong partnerships with key stakeholders, such as the municipality, financiers and other actors within the briquette value chain, and enabling policy are important drivers for the success of briquette businesses.

On-site sanitation systems, such as septic tanks and pit latrines, are the predominant feature across rural and urban areas in most developing countries. However, their management is one of the most neglected sanitation challenges. While under the Millennium Development Goals (MDGs), the set-up of toilet systems received the most attention, business models for the sanitation service chain, including pit desludging, sludge transport, treatment and disposal or resource recovery, are only emerging. Based on the analysis of over 40 fecal sludge management (FSM) cases from Asia, Africa and Latin America, this report shows opportunities as well as bottlenecks that FSM is facing from an institutional and entrepreneurial perspective.

Biological treatment, composting, in particular, is a relatively simple, durable and inexpensive alternative for stabilizing and reducing biodegradable waste. Co-composting of different waste sources allows to enhance the compost nutrient value. In particular, integration of ‘biosolids’ from the sanitation sector as potential input material for co-composting would provide a solution for the much needed treatment of fecal sludge from on-site sanitation systems, and make use of its high nutrient content. This research paper elaborates in detail the main parameters that govern the co-composting process as well as factors that control the production of a safe and valuable quality compost. It further explains technological options to tailor the final product to crop and farmer needs.