Comprehensive coverage

A new treatment of human excrement may improve sanitation and provide a source of energy

For the first time, wet human excrement has been converted into a coal-like material known as hydrochar, capable of dealing with sanitation challenges and increasing energy demand

A sewage treatment plant in the Czech Republic. Photo: shutterstock
A sewage treatment plant in the Czech Republic. Photo: shutterstock

A new study at Ben-Gurion University in the Negev has shown that human excrement (feces and urine) can be reused by turning it into a coal-like substance known as hydrochar, which may be used as fuel as well as a liquid rich in nutrients, which can be used for fertilization. The proposed treatment is a solution to two major global problems regarding sanitation and the creation of sustainable renewable energy.

According to a groundbreaking study published in the Journal of Cleaner Production, researchers at Ben-Gurion University of the Negev's Zuckerberg Institute for Water Research investigated the conversion of human excrement into a charcoal-like substance through a process called hydrothermal charring (HTC). In this process, human excrement is heated in a "pressure cooker" to high temperatures (240-180 mC) and under a pressure of up to 35 atmospheres. Under these conditions, chemical processes occur that cause the solid to become hydrochar. Because of the high temperature, the "products" that are obtained are sterilized and safe to use from a sanitary point of view. Ben-Gurion University researchers conducted a similar study last year on poultry droppings.

The development addresses two challenges prevailing in the developing world: sanitation (sanitation) and an increase in energy needs (on-site). While access to waste treatment in the world has expanded significantly in recent years, approximately 2.3 billion people still lack access to safe sanitation facilities. Of these, about 892 million people, mainly in rural areas, defecate in the open. The Bill and Melinda Gates Foundation considers sanitation a major global health problem, and initiated the Reinvent the Toilet Challenge to tackle this problem.

"Human excrement is considered dangerous due to its potential to transmit diseases," says Prof. Amit Gross, the new director of the Zuckerberg Institute for Water Research. "It is also rich in organic matter and nutrients such as nitrogen, phosphorus and potassium, in addition it contains micro pollutants and drug residues, all of the ingredients can lead to environmental problems if we do not treat or use them properly."

Lack of energy (on-site) is another difficult challenge. About two billion people in the world use solid biomass, mainly wood converted to charcoal, which is used for cooking and heating. These methods cause unprecedented environmental destruction - air pollution, greenhouse gas emissions, deforestation and soil erosion are just some of the effects of using wood.

"By treating the human waste, we can address these two issues together," added Prof. Gross.

2 תגובות

  1. What is the energy consumption of the process to produce a ton of product? And what is the amount of energy that can be produced from a ton of product?

Leave a Reply

Email will not be published. Required fields are marked *

This site uses Akismat to prevent spam messages. Click here to learn how your response data is processed.