Effective urine treatment system for dry toilets



This technology is about effective urine treatment system for dry toilets

Technology Description

Current sewage system uses a lot of drinkable water and consume large amounts of energy to treat the waste. The system is outdated and needs improvements. In next 30 years, the world cities will be doubled in infrastructure needed for life.

Mobile toilets in developed countries are using chemicals and are made of plastic. The user experience in this cabin is one of the worst possible.

2.4 billion people lack access to basic sanitation services, such as toilets or latrines (source: www.un.org). The Sustainable development goals, supported by all UN candidates, agreed to offer an affordable solution for sanitation for the population needing proper sanitation. That’s around 1 billion toilets to build in the next 30 years.

There are many solutions made especially for solids but very few for the liquids. The liquids are less polluted with pathogen bacteria but are in a large amount.

Short student project CONVERT, performed on Environmental Protection Collega (EPC) last year, was aiming to develop a dry toilet of the future. The concept is divided into two subprojects, construction of a local wastewater treatment system and a sustainable but affordable toilet cabin. The 1st subproject would be solved within this technology project:

The wastewater system is designed to separate solids and liquids. It is focused on treating the liquids with the help of the sun and plants. The idea is to transform the urine into as clear, healthy water as possible and that can be released in nature. During the process, the liquid full of nutrients help plants to grow. The plants can possess an important role in cleaning the air as well.

Inventors want to make an autonomous dry toilet that won’t need any infrastructure. The second aim is to grow plants that can clean the air, what is an optimal solution for big city centres. The plants can be later on used in mixture with solids from the toilet and uses as biomass for heating or producing electricity.

The system separates solids and urine with processes based on gravity and filters. The urine goes in two reservoirs to raise the pH and kill most pathogens. To make a 100% safe liquid, it is poured through a basin heated with the sun. The hot liquids needs additional time to cool and used with plants. The plants extract nutrients from the liquid, clean the air and produce a biomass that can be reused in different ways. It can be placed in the environment as an individual toilet or a group of toilets.

Main advantages

  • affordable solution for sanitation for the population needing proper sanitation
  • transform the urine into as clear, healthy water
  • autonomous dry toilet that won’t need any infrastructure
  • urine goes in two reservoirs to raise the pH and kill most pathogens

Stage of development

Inventors researched and discussed all available and potentially applicable technologies during the previous CONVERT project. As a result they suggested a wastewater treatment system that doesn’t need infrastructure to treat the human waste and they created a 3D model concept of a cabin with sustainable materials to implement the solution (Convert ecotoilet prototype). Inventors got many opinions from experts and they prepared the optimal solution regarding the feasibility and implementation of the system with the cabin.

The expected performance of the system is very efficient since it doesn’t need an infrastructure, transport of the waste to a treatment system and treatment of the waste mixed with different chemicals from the system. There is also no need for water, even though the system will use small quantities of rainwater or already treated water.

Additionally, they performed an overall design and operation of the Convert ecotoilet prototype in a large elaborate publication.

Challenge and needs

Inventors have a big opportunity to prepare a sewage system that will use almost no water and will treat all the waste locally with the help of the sun and plants. Like this we can lower the need for energy, almost eliminate the need for water and improve the microclimate due to additional plants.

The 2nd subproject is to design a durable and affordable outdoor cabin. Inventors are planing to use the thermo treated wood to prolong the durability of the wood. For the foundation and the bottom of the toilet, they will use panels made from trash. The outdoor toilets that can be put in the city centres, rural parts, parks, hills, etc.

Intellectual property

The technology is not yet protected by a patent.

Potential markets and targets

There is a big opportunity to make an affordable toilet solution that can be implemented in the developing countries all around the world. Solution is very useful and promising for countries in development (Africa, Asia and South America) as there the population is booming and increasing very quickly.

As a sustainable solution for places without infrastructure, we can target also developed countries. Such places are mountains, places close to water, natural parks, etc. The system can be installed also in places with infrastructure as it needs no additional construction costs. Campsites, restaurants, hiking huts etc, also are searching for similar solutions.

The rental toilet market is using outdated plastic cabins that mixes human waste with chemicals. This trend is slowly changing due to more and more event organisers are searching for user friendly and ecological solutions. Additionally, when big events needs a lot of toilets, we can process the liquids on site with no need to mix them with chemicals and with no need to transport them to the treatment system.

There is also a possibility to develop the next version of sewage system that will be more effective, less energy and water demanding and designed on principles of circularity.

Key competitors are small scale treatment systems but also public owned sewage systems and treatment plants.

Potential partners

Inventors already performed the project CONVERT with a local company producing ecological dry toilets and that would definitely be the one to be connected to. The construction should be also supported by an expert in the development of constructed wetlands. For the further development of the cabin they will connect to the technical faculties.

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