Urine might have a distinct smell, but for William Tarpeh, an Environmental Engineering PhD student at UC Berkeley, it represents a fascinating opportunity. His field combines engineering, biology, and chemistry to tackle environmental challenges such as air pollution, water contamination, and waste reduction. Among the unique individuals in this field, Will stands out for his innovative approach to turning urine into liquid fertilizer, transforming what many consider waste into a valuable resource.
Will’s work focuses on extracting nitrogen from urine, a key component in fertilizers. His goal is to create a product that can be sold, making sanitation self-sustaining. This is particularly important because, while basic sanitation is often taken for granted in the West, it remains a critical public health issue for 2.4 billion people worldwide. By generating value from waste, Will hopes to fund the construction of more toilets, improving sanitation globally.
Urine naturally contains nitrogen, phosphorus, and potassium, essential nutrients for fertilizers. For four years, Will has been working on converting urine into a nutrient-rich fertilizer. To conduct his research, he collects urine from his labmates at Berkeley, who support his project. The urine is then left to “cure” for a week, during which the nitrogen in the form of urea is hydrolyzed into ammonia, thanks to the enzyme urease. This ammonia serves as the starting point for Will’s extraction methods.
Will has developed two methods to isolate nitrogen from urine. The first is electrochemical stripping, which uses an electrochemical cell with three chambers to filter nitrogen selectively. Urine enters the first chamber, and a dilute salt solution is added to the middle chamber. When electricity is applied, ammonium is pushed through a membrane into the salt solution.
The second method involves an ion exchange column, a tube filled with negatively charged resin. The positively charged ammonium binds to the resin beads, while the rest of the urine passes through. A dilute acid is then used to release the nitrogen back into solution.
To test his innovations in a real-world setting, Will partnered with Sanergy, a company that builds toilets in Nairobi, Kenya’s slums. Sanergy already converts waste into fertilizer, but Will’s methods allow them to utilize the large amounts of urine they previously discarded. This past summer, both technologies were tested in the field using real urine collected daily.
Looking ahead, Will is considering the challenges of scaling up his methods to treat larger volumes of urine. If successful, his work could significantly impact billions of people worldwide, combining environmental interests with practical solutions focused on the chemistry of urine.
We extend our gratitude to the Blum Center for Developing Economies at UC Berkeley, a hub for innovation and research addressing global poverty issues. Technology is transforming lives in the developing world, from using cell phones as handheld microscopes to diagnose malaria to Will’s groundbreaking work with urine.
Have you ever repurposed something that was once considered waste? Share your experiences in the comments, and stay tuned for more updates. Thank you for engaging with this exciting journey of innovation!
Join a seminar where you will explore the concept of waste valorization. Discuss with peers how waste materials can be transformed into valuable resources, using William Tarpeh’s work as a case study. Prepare a short presentation on how you envision applying similar principles in your field of study.
Participate in a lab session where you will simulate the process of extracting nitrogen from a synthetic urine solution. Use basic lab equipment to mimic the electrochemical stripping and ion exchange methods. Document your findings and reflect on the challenges and potential improvements.
Conduct a field study in your local community to analyze current waste management practices. Identify potential opportunities for waste valorization, inspired by the urine-to-fertilizer conversion. Prepare a report suggesting innovative solutions to improve local waste management systems.
Engage in a group discussion about global sanitation challenges and the impact of innovative solutions like those developed by William Tarpeh. Consider the social, economic, and environmental implications of implementing such technologies in different regions of the world.
Work in teams to design a sustainable sanitation system for a community with limited access to sanitation facilities. Incorporate elements of waste valorization and resource recovery, drawing inspiration from the urine transformation process. Present your design to the class, highlighting its potential benefits and feasibility.
Here’s a sanitized version of the YouTube transcript:
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It has a distinct smell, but that’s okay because to me, urine is fascinating. This is William Tarpeh, an Environmental Engineering PhD student from UC Berkeley. His field of study harnesses the principles of engineering, biology, and chemistry to develop solutions to environmental problems. Environmental Engineers tackle issues like air pollution, contaminated water, and reducing waste. But like in any field, there are unique individuals, like Will.
Will spends his time transforming urine into liquid fertilizer, attempting to create something valuable from what many of us flush away without a second thought. He focuses on the nitrogen in urine, which is also a key component in fertilizers. His big idea is to extract nitrogen from urine into a product that can be sold.
Will’s motivation for making urine profitable is related to sanitation. While basic sanitation is taken for granted in many parts of the West, it remains a significant public health issue for 2.4 billion people worldwide. He believes sanitation is fundamental and affects many aspects of life that often go unnoticed. His goal is to find ways to make sanitation self-funding by creating value from waste, which can help generate the funds needed to build more toilets.
Fertilizer contains nitrogen, phosphorus, and potassium, all of which are naturally found in urine. For four years, Will has been working on transforming urine into a nutrient-rich fertilizer. To do this, he needs a consistent supply of urine for his research. When he’s at Berkeley, he files paperwork to collect urine from his labmates, who are quite supportive of the project.
Once he has enough urine, he lets it sit for a week, a process he refers to as “curing.” When we excrete urine, the nitrogen is present as urea, an organic compound. Over the course of a week, urea is hydrolyzed, meaning it is converted into ammonia in the presence of water and an enzyme called urease. This ammonia is the starting point for his work.
Will has developed two extraction methods to isolate the valuable nitrogen for fertilizer. The first method is called electrochemical stripping, which uses an electrochemical cell with three chambers to selectively filter nitrogen from the urine. The urine enters the first chamber, and a dilute salt solution is introduced into the middle chamber. When electricity passes through, ammonium is pushed through a membrane into the salt solution.
The second method is an ion exchange column, which is a tube filled with negatively charged resin material. The nitrogen, part of the ammonium, is positively charged, allowing it to bind to the resin beads while the rest of the urine passes through. A dilute acid is then used to release the nitrogen back into solution.
Will wanted to see if his innovations could work in a real-world setting, so he partnered with Sanergy, a company that builds toilets in the slums of Nairobi, Kenya. Sanergy already collects waste and turns it into fertilizer, but before Will’s innovations, they were disposing of large amounts of urine daily. This past summer, they tested both technologies in the field with real urine collected every day.
After testing in Nairobi, Will is considering the future challenges of scaling up his methods to treat larger volumes of urine. If successful, his work could help transform the lives of billions of people globally. He aims to combine his environmental interests with impactful solutions, focusing on the chemistry of urine.
We want to thank our partner, the Blum Center for Developing Economies at UC Berkeley, an innovation and research hub addressing global poverty issues. Technology is changing lives in the developing world, such as using cell phones as handheld microscopes to diagnose malaria quickly.
Have you ever reused something that was once considered trash? Let us know in the comments, and make sure to return for more updates. Thank you for watching!
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This version maintains the core content while removing any inappropriate or overly casual language.
Waste – Materials that are discarded after primary use, often considered as by-products of human activities and processes. – Effective waste management is crucial to minimize environmental impact and promote sustainability.
Nitrogen – A chemical element with the symbol N, essential for the growth of plants and a major component of the Earth’s atmosphere. – Nitrogen cycles through the environment, playing a critical role in ecosystems and agricultural productivity.
Fertilizer – A substance added to soil to enhance the growth of plants by providing essential nutrients. – The overuse of chemical fertilizers can lead to nutrient runoff and water pollution.
Sanitation – The development and application of measures designed to maintain hygiene and prevent disease, particularly through the disposal of waste and sewage. – Improved sanitation facilities are vital for public health and environmental protection.
Pollution – The introduction of harmful substances or products into the environment, causing adverse effects on ecosystems and human health. – Industrial activities are a major source of air and water pollution, necessitating stringent regulatory measures.
Chemistry – The scientific study of the properties, composition, and transformation of matter. – Understanding the chemistry of pollutants is essential for developing effective remediation strategies.
Engineering – The application of scientific and mathematical principles to design and build structures, machines, and systems that address specific problems. – Environmental engineering focuses on designing solutions to reduce pollution and manage natural resources sustainably.
Urine – A liquid by-product of metabolism in humans and animals, often studied for its potential use in nutrient recovery and recycling. – Researchers are exploring the use of urine as a sustainable fertilizer alternative due to its high nutrient content.
Extraction – The process of removing or obtaining a substance from a mixture or compound, often used in the context of resource recovery. – The extraction of metals from electronic waste is an important aspect of recycling and resource conservation.
Nutrients – Substances that provide nourishment essential for growth and the maintenance of life, often discussed in the context of soil and plant health. – The balance of nutrients in soil is critical for agricultural productivity and ecosystem stability.
