In a recent report, the World Bank highlighted that the global demand for freshwater is projected to exceed supply by 40% in many regions worldwide by 2030. Given freshwater’s underpinning role in society and its role as a critical component in the UN’s Sustainable Development Goals (SDGs) initiatives, as well as the economic recovery from Covid-19, the increase in demand caused by population growth, urbanisation, climate change and competition for water resources will require consumers, businesses and governments to devise more efficient water usage and preservation strategies. A key area where improvements can be made in water usage is in the agriculture and food processing sectors. The World Bank estimates that about 70% of global freshwater is used in agriculture production, and in the coming decades, it is expected to be the primary driver of demand to meet the needs of a growing population. But when freshwater is used in agriculture and food processing, anything that is used comes out as wastewater – which is a significant concern because 80% of global wastewater flows back into the ecosystem without being treated; this depletes water quality and causes public health problems from the contaminants that end up in ground and surface waters.
As the agriculture and food processing sectors look to become more environmentally sustainable, resolving the challenge around wastewater management will be central to their efforts, not only from a corporate sustainability perspective but also to reduce the operational costs associated with municipal discharge, in-house water treatment and energy usage. To help address some of these issues, the emergence of new technologies can offer ways to potentially treat and manage wastewater more efficiently. One company that is helping the food and beverage manufacturing sectors to manage wastewater challenges is Aquacycl. By using microbial fuel cells (MFCs) to treat wastewater, Aquacycl’s CEO, Orianna Bretschger, and her team are developing a decentralised water treatment system that offers manufacturing plants a flexible plug-and-play system to reduce the high capital expenses of onsite wastewater treatment and generate electricity by cleaning wastewater using their BioElectrochemical Treatment Technology (BETT). In an interview, Bretschger provided insights into Aquacycl’s MFC technology, ways the food and beverage sectors can become more sustainable by using it and policies that can spur greater adoption of watertech solutions in the coming years.
Using electricity-producing microbes to accelerate treatment and produce clean energy
According to the International Energy Agency (IEA), the water sector, which includes collecting and treating wastewater, accounts for 4% of total global electricity consumption, with some estimates putting the sector’s share of total greenhouse gas emissions at 3%. Additionally, wastewater treatment alone represents roughly a quarter of the sector’s electricity consumption. As countries face not only freshwater supply and demand challenges but also environmental challenges, improving efficiencies in the water sector will be critical, especially given that the standard process of removing toxic organic pollutants from wastewater requires burning coal for electricity, diesel fuel (trucking) and natural gas (incineration). To help address some of these core issues, Bretschger said in an interview that “the wastewater produced by manufacturing facilities is often discharged to centralised treatment facilities – adding a higher treatment burden to an expensive and energy-intensive operation. If operations cannot discharge to sewer, they may be forced to haul wastewater to another location for treatment or land-application.” Hence, Bretschger suggested that a more scalable solution would be to shift towards decentralised treatment facilities that can provide a more flexible and efficient way for these plants to manage their wastewater discharge and avoid the energy-intensive transportation and/or burden to centralised facilities.”
In developing new decentralised treatment systems, Bretschger noted that MFC technology could provide a unique way to treat low-volume and high-concentration wastewater from industrial food & beverage processing plants. Although the technology is emerging and may not be the silver bullet for every application, Bretschger highlighted that based on the initial results from Aquacycl’s pilot projects, food and beverage plants were able to “improve their operational savings by 20-60%, accelerate treatment time by 10x and reduce GHG emissions up to 50% – by using the clean energy produced by the electricity-producing microbes – when compared to traditional wastewater management practices.” At a time when public health problems have started to emerge because of poor water quality, it is becoming crucial for companies, particularly those in the food and beverage sectors, to optimise their water usage and work towards zero liquid discharge (ZLD). As a potential solution to address water problems, Bretschger pointed out that Aquacycl’s BETT system, which uses MFCs, can help the industry because the technology removes 90% of the carbon (BOD), 70% of suspended solids (TSS), 100% of sulphur and about 30% of the nitrogen from wastewater after which food and beverage producers can consider reusing the water within specific applications (e.g. for cooling water and irrigation).
Partnering with engineering firms to develop treatment systems for food processing plants
Given the initial technology risk, high upfront capital and operational expenditure associated with MFC, deploying the technology in the food and beverage industries can be slow. However, as McKinsey’s recent report showcases, two-thirds of businesses face operational risks from the challenges arising from the limited freshwater supply. This growing trend is prompting leading companies to adopt new technologies in order to improve their water usage, and it presents opportunities for watertech solutions like MFC to enable these companies to reuse their wastewater. According to Bretschger, the best way to navigate the barriers to deployment is to “form partnerships with the engineering companies that are designing and installing treatment systems at food and beverage plants.” Through these partnerships, and based on the projects, Bretschger said that the “engineering companies could adopt new watertech solutions, such as MFCs, when developing treatment systems for ZLD.”
Given the trend towards achieving ZLD and reducing water usage per product produced, the knock-on effect from this process in the food and beverage industries can often generate more concentrated wastewater streams that create challenges in treating wastewater using conventional methods. For these reasons, and along with the growth in the sector, Bretschger believes Aquacycl’s BETT systems can play an important role in devising ways to treat concentrated wastewater and support the industry move towards ZLD. In past years, Bretschger said, “Aquacycl’s customers have seen the value of onsite wastewater treatment at a bottling company which would normally spend tens of thousands of dollars per month to discharge to sewers. Using the BETT system allows them to eliminate uncertain charges from the city and save 20–30% of their costs.” Through such deployments and learnings from the industry, Bretschger added that Aquacycl would look to further develop their treatment systems that “remove carbon and other contaminants from wastewater, which is becoming a major problem for the industry, and continue to extract the energy potential of the BETT system to create long-term value for customers in the transition to a low-carbon economy.”
Aligning regional policies with more funding can help scale wastewater technologies
In a recent report, the American Society of Civil Engineers (ASCE) estimated that the annual drinking water and wastewater investment gap would reach $434 billion in the United States by 2029. As municipal/regional governments face financial constraints following the Covid-19 pandemic, bridging the nation’s ageing water infrastructure gap will require leveraging new technologies to optimise the water treatment process and ramping up reclaimed wastewater use among industrial plants. By taking these measures, local and regional governments can reduce demand for freshwater and build smarter and climate-resilient cities in the coming years. But to proceed with the necessary next steps, Bretschger said that one of the key measures needs to be “treating wastewater, particularly from food processing plants, closer to the source by setting up distributed treatment or industrial pretreatment facilities. To help develop these facilities, government funding opportunities will have to be made available for distributed treatments or industrial pre-treatment, not only the POTW (publicly owned treatment works).”
However, Bretschger acknowledged that to attract capital and enable the industries to develop decentralised wastewater treatment systems, the “costs would need to come down to fully deploy watertech technologies.” Bretschger added that as water policies tend to be very regional, synchronising policies that help “accelerate permitting and testing for water technologies, along with financial incentives for food processing plants to adopt new wastewater management practices, would support bringing new products to the market and reduce costs.” As for MFC technology, which has specific use cases for high-concentration wastewater treatment and the added benefit of energy production, Bretschger highlighted that more public and private investment is needed to deploy the technology into mainstream commercial use. In order to attract more venture financing, Bretschger noted that “greater research insights into where the technology works or doesn’t work and broader clarification of how it fits into overall wastewater treatment with details on the energy potential of MFC technology would help investors conduct due diligence and make investment decisions more easily.”