Human Practices

Overview

Our project aims to revolutionise wastewater treatment by developing an innovative method for phosphate recovery. Traditional phosphate mining practices have significant environmental and health implications, including air pollution, loss of biodiversity, and the use of harmful chemicals. By reclaiming phosphate from wastewater, we seek to reduce our reliance on destructive mining operations while providing a sustainable solution to a pressing environmental issue.

Our project aligns with several key environmental and social values. From a scientific perspective, we are committed to advancing sustainable technologies that minimise environmental harm. Our work addresses the pressing issue of phosphate runoff, which contributes to eutrophication and degrades water quality. By reducing phosphate pollution, we are directly benefiting communities that rely on clean water sources.

Moreover, our project offers a potential solution to the negative impacts of phosphate mining. Traditional mining practices often involve the use of harmful chemicals, such as sulfuric and nitric acids, which can contaminate natural water sources. By reclaiming phosphate from wastewater, we can reduce the demand for mining and mitigate these environmental risks. (Reta et al., 2018)

To ensure the success and sustainability of our project, we have engaged with various stakeholders, including researchers, wastewater treatment experts, and local communities. Through collaboration and feedback, we have gained valuable insights into the practical challenges and opportunities associated with our technology. To read more about our collaboration with various professionals, see the “Interactions” section below!

Our vision is to see our project implemented in wastewater treatment facilities worldwide. By integrating our phosphate recovery method into existing infrastructure, we can significantly reduce phosphate pollution and contribute to a more sustainable future. To facilitate the adoption of our technology, we are working to develop scalable and cost-effective solutions that are adaptable to different operating conditions.

While our project offers significant benefits, it is important to acknowledge potential challenges and risks. One concern is the potential contamination of wastewater treatment systems with PFAS, a group of persistent organic pollutants. To mitigate this risk, we are exploring alternative materials and processes that avoid the use of biowaste, a potential source of PFAS contamination. See interview with John Godber from Nutrien for further information.

Additionally, the implementation of our technology may require additional infrastructure or modifications to existing wastewater treatment plants. In areas with limited resources, this could pose a challenge. To address this, we are working to develop cost-effective solutions and explore opportunities for partnerships and funding.

Finally, the transition to a phosphate-recovery-based economy may have implications for the mining industry. Closer to home, the Woodsmith mine in Whitby in North York Moors National Park, and Morocco's phosphate industry, which accounts for 10% of GDP and 20% of exports, could be significantly impacted. To minimise disruptions and job losses, we are advocating for a gradual transition that allows for a smooth adjustment. With that being said, it’s important that the whole world doesn’t come to rely on a small handful of already-wealthy countries (like the UK) for their fertiliser. Though the phasing out of phosphate mining may impact the short-term prosperity of those living and working near the Woodsmith mine, it unshackles the rest of the world’s agricultural industries from the UK and means they don’t have to pay potentially exorbitant prices from a nation that has far more wealth to begin with. Balancing these concerns, we believe that by working closely with stakeholders and investing in retraining and job creation programs, we can ensure a just and equitable transition.

To achieve our goals, we planned a multi-faceted approach that includes:

  1. Utilising AI to generate efficient variants of specific enzymes that are more robust and reusable — reducing the cost of maintaining these enzyme-based treatment systems
  2. Engaging with stakeholders in wastewater treatment to gather insights into operational challenges and how to best integrate our enzymes into the existing infrastructure.
  3. Partnering with local researchers to analyse existing phosphate recovery processes and identify areas for the further improvement of our engineered PafA.

Summary of Interactions with Experts, Academics and Governments:

Lance Kautz - Florida Department of Environmental Protection (FDEP):

lance

Phosphate mining, particularly through open-pit methods, has significant environmental and community impacts. After phosphate is extracted, the mined areas must be carefully restored to their natural state, often requiring replanting native species to re-establish ecosystems such as swamp-marsh habitats. The restoration process must meet specific classification standards such as including the appropriate fauna and flora to ensure that these lands can return to their original state.

By streamlining processes, reducing costs, and enabling the recovery of valuable products like phosphorus-enriched biosolids, these systems can provide significant advantages to communities and private sectors alike. These biosolids, rich in nutrients, are especially valuable as fertilisers in nutrient-deficient regions such as the Caribbean and the Midwest, supporting sustainable agriculture. Nonetheless, careful management is necessary to avoid creating dead zones in discharge areas due to excessive nutrient filtration. When properly managed, this technology not only aids in meeting phosphorus discharge limits but also contributes to the enhancement of soil quality, exemplified by its use in sustainable practices like maintaining FIFA pitches in the U.S.


Changes Made as a result:

Considering the simplicity of storing inorganic phosphate with the biowaste that accumulates at the bottom of the waste treatment plant, this solution is ideal for transportation and use in farming. While using this technology in a municipal setting may raise ethical concerns around generating profit from public funds, it’s better suited for private companies. The profit-driven nature of private enterprises aligns with the financial model of this technology. Additionally, since private companies prefer hauling over piping their waste, this approach seamlessly integrates into our logistics plan. Overall, the meeting with the FDEP helped us to tilt our project to be more targeted towards a private enterprise rather than public one and encouraged the reuse of biowaste that is accumulated to be the medium in which the inorganic phosphate is collected. The negative implication of the use of private enterprise for this kind of treatment is that it might not be available for public water treatment plants, and can possibly cause the end product to be priced at a level that is less affordable to the public.


ConX:

conx

Changes Made as a result:

As one of the 20 finalists in the Amazon challenge, we have been put into contact with other teams and past finalists, as well as them providing financial support to our team (so big thanks to Conservation X for their ongoing support!). Conservation X helped put us in contact with Leigh from Nibeenabe - winners of the Earthshot prize. She developed a system for collecting heavy metals from water runoff from mining in the Amazon. This prevented further heavy metal contamination in an already heavily polluted water system, as well as reclaiming the heavy metals to generate an additional revenue source for the miners. This incentivised their engagement with preventing pollution, whereas previously it would have cost them money to prevent this sort of pollution, often making it unaffordable. Leigh advised us that in order to make the system of removing phosphate from water accessible globally, we need to consider that there are different wastewater systems locally, and in many cases there may be none. We had initially considered focusing on fertiliser runoff from farmland, however due to her experience of working with runoff, she advised us that collecting all the runoff may not be feasible in many locations. For our initial ideas, she advised we focus on integrating into already existing wastewater treatment facilities as this would mean less infrastructure would need to be developed. In the future, it would be helpful to think about how we make this system more accessible to more remote areas.


John Godber - Nutrien:

nutrien

Nutrien's phosphate mining activities are focused on extracting apatite, a mineral comparable to that found in bones and teeth. Although the mineral is not very pure, its phosphate level is critical to Nutrien's manufacturing process. Phosphate is determined by its P₂O₅ content, which normally ranges from 35-37%. The remaining composition consists of other elements such as magnesium. Regardless of the contaminants, Nutrien follows industry requirements to maintain the quality of its phosphate. Nutrien also keeps all byproducts on-site to prevent eutrophication and harmful algal blooms.


The corporation has two big phosphate mines, one in North Carolina and the other in Northern Florida. In North Florida, phosphate ore is found near the surface, allowing unwanted minerals to be returned to the ground following extraction. Meanwhile, the North Carolina mine is focussing on replenishing the land with gypsum, a byproduct of phosphate mining, to aid environmental rehabilitation. Both sites prioritise ecosystem restoration by replacing native plants and requiring that mining activities be followed by remediation measures.


Nutrien carefully obtains phosphate resources with a minimum P₂O₅ level of 32.5% and a target of 36%. In some circumstances, they look into alternative sources, such as human waste from water treatment plants, which can also include phosphate. However, the sector faces PFAS contamination concerns, particularly in the United States, where water treatment sludge contains hazardous chemicals detected in alarmingly high proportions in wildlife. This issue has sparked worries about environmental damage and the safe recovery of nutrients from sewage sludge.


Changes Made as a result:

Speaking with Nutriens made us realise that the fact that mining phosphate over reclaiming it from waste water and then applying it via sludge was preferred was due to the issues surrounding the latter. Reclaimed phosphate which is applied via sludge to farms carries the risk of diseases alongside the issue of PFAS, a highly toxic chemical, along with other PFAS derivatives such as PFOS which can cause issues such as kidney cancer and fertility issues. Nutriens had researched their competition when it came to phosphate exports and found that those that used reclaimed phosphate fared worse than mined phosphate. After releasing this we understood that to be effective in the real world without causing further problems to ecosystems and to human health, we would need an alternative strategy. We needed to avoid the use of the biowaste which contained the carcinogenic chemicals yet needed a way to obtain the phosphate. As a solution, we are trying to use a phosphate binding protein which creates a pure inorganic phosphate product after the conversion step. This would be incorporated onto the column device and would not require the use of the biowaste which contains PFAS and so would be significantly less dangerous to be used in human farms for agriculture. This would mean that a reason behind the minimal use of reclaimed phosphate application via sludge would be avoided and the project has a more legitimate basis now due to its alternative strategy of application not coming with the risk of carrying diseases or life threatening conditions if applied to food.


Dr Eleni Routoula - University of Sheffield

eleni

During the meeting, Dr. Eleni Routoula emphasised the importance of enzyme immobilisation as a vital step in the effective application of enzymes within water treatment processes. She explained that immobilising enzymes can significantly enhance their stability and reusability, which are critical factors for their practical implementation in industrial settings. By attaching enzymes to suitable carriers, their operational lifespan can be extended, leading to more cost-effective and efficient water treatment solutions.


Dr. Routoula outlined various methods for enzyme immobilisation, such as covalent bonding, adsorption, and entrapment, each with its own advantages and challenges. She stressed that selecting the appropriate immobilisation technique is crucial, as it directly affects the enzymes' activity, accessibility to substrates, and overall performance in real-world applications. By focusing on enzyme immobilisation, the project can ensure that the developed solutions are not only effective in treating phosphate pollution but also viable for large-scale use.


Changes Made as a result:

After the meeting we chose to go forward with a water-based enzyme treatment solution as it would be more practical to include beads that wastewater would flow past as this would be more reusable and more efficient in filtering phosphate from wastewater. She also helped grow the idea of enzyme immobilisation on to beads that would then catalyse the reaction of organic to inorganic phosphate.


Leigh Cassidy - Nibeenabe

nibeenabe

The meeting focused on the innovative water treatment technology known as DRAM (Device for Remediation and Attenuation of Multiple Pollutants). Leigh, the primary speaker, shared her experiences deploying this system in remote mining locations, highlighting its dual functionality: extracting valuable metals such as gold and silver from contaminated water and simultaneously producing clean water suitable for irrigation and industrial applications. This approach not only benefits mining operations by reclaiming high-value materials but also addresses environmental concerns by mitigating water contamination.


A significant aspect of the discussion revolved around the design considerations for implementing DRAM. Leigh emphasised the use of local materials to create sustainable filtration systems, explaining how her background in the whiskey industry contributed to developing effective organic filters. The technology's low-tech nature makes it ideal for remote areas where access to sophisticated infrastructure is limited. This adaptability is essential for ensuring the system's feasibility in varied environments.


Further, the meeting explored the potential for integrating the system into both agricultural runoff management and existing water treatment plants. Leigh cautioned that while addressing agricultural runoff presents challenges—such as the need for efficient collection—the development of a versatile system could enhance the technology's applicability. By creating a solution that can work in both contexts, the team could maximise environmental impact and broaden the system's user base.


The conversation also touched upon potential revenue models to incentivize adoption of the technology. Opportunities for recovering phosphates from treated water were discussed, presenting a dual advantage: reducing pollution entering waterways and providing a sustainable fertiliser alternative. This aligns with environmental goals, addressing issues related to heavy metal contamination from traditional phosphate fertilisers. Overall, the meeting underscored the promising capabilities of the DRAM system in tackling water pollution and its broader implications for sustainable practices.


Changes Made as a result:

Following our discussions with Leigh, we recalibrated our focus toward optimising wastewater treatment. This strategic shift is grounded in the insights gained during the meeting, where Leigh emphasised the practicality of managing wastewater due to its more accessible collection and processing compared to the complexities typically associated with agricultural runoff. By focusing on wastewater, we align our efforts with an approach that not only addresses immediate environmental challenges but also capitalises on the existing systems for capturing and treating water. This decision reflects a commitment to developing efficient and scalable solutions that enhance water quality while reclaiming valuable resources.


References