Hydrothermal gasification: a surprising waste recovery solution

Tell us about your start-up.

TreaTech works in waste processing, with a strong focus on liquid waste. In particular, we process wastewater sludge, i.e. concentrated waste that remains after processing by wastewater treatment plants, but also slurry, industrial sludge, industrial solvents, etc. We have developed a very specific technology, both to get rid of this waste and above all to transform it into valuable resources.

What solution did you develop?

It is based on catalytic hydrothermal gasification – an innovative technology, much like pyrogasification a few years ago. In the first instance, the process allows us to extract the mineral portion of the waste – sewage sludge in particular contains a lot of minerals, ash, salts, etc. Some components are valuable to recover, and their processing is even starting to be regulated. These include phosphorus and other nutrients that can be used to make fertilisers. Once the mineral component of the waste has been extracted, we are left with water and organic matter, which is converted into synthetic gas – a kind of biogas composed of a lot of methane, a little bit of hydrogen, and a little bit of CO2. 

How is this innovative? 

This process is highly efficient both from a technological and an environmental perspective, because it does not generate any final waste and avoids the use of landfill or incineration. Incinerating sludge with around 95% water content requires a lot of equipment, energy consumption, and so on. At TreaTech, we work directly with the waste in its liquid state. Everything is used: the minerals are extracted and recycled in the form of fertilisers, and the organic portion is converted into synthetic gas that can either be used by the customer on site, or purified and injected into the network. The resultant clean water is considered industrial water, so it can also be used on site. 

What are you going to present at VivaTech?

Our prototypes are too large and too heavy to be displayed at Viva Technology. But we will show videos and on-screen presentations. And of course the related documentation. 

What do you hope to achieve from your participation? 

We will be part of ENGIE’s start-up portfolio. We want to make our solution better known and gain some visibility from the event. 

Who are your potential customers? 

We are looking to local authorities (wastewater treatment plants, towns, etc.) and industrial companies, in two main areas: food production (sugar and coffee producers, etc.) and chemicals and petrochemicals. Our technology could also be of interest to farmers seeking better ways to recover their waste and at lower cost.

What would you invent if you had one magic power?

A machine that controls the weather!