Introducing Scissors: Super Critical Industrial Solution for Suspended Organic Residual Streams

Society is becoming increasingly aware of scarcity of natural resources, as well as effects of climate change. This has created a quest for processes that enable re-use of materials. While at the same time, reduce the emission of greenhouse gasses. The SCISSORS-project aims to research and enable the processing of sustainable residual streams through the potential of super critical water technology. 

To this day, wet residual streams remain energy intensive or difficult to process. Sometimes, it isn’t even impossible. At present, incineration or, simply, land fill are the best solutions available. Many sources of this nature can be identified with a great diversity of origin. Ranging from agricultural waste, domestic sewage to industrial flush waste streams.  

Therefore, the SCISSORS-project has an ambition to search for ways to process these wet waste streams in a better and circular way, in a CO₂ neutral way. We aim to retain the building blocks, including the water. Recent development in the area of super critical water processing offer new opportunies to address the issues mentioned. This combined with a new awareness of the activities of SCW-Systems triggered the idea that this technology may offer that opportunity.   

Potential impact of the project  

The potential impact of this technology is best illustrated by the size of the streams that may be suitable for processing. In the Netherlands, wastewater treatment plant sludge out of municipalities of already 1.4  million tons per year. The industrial wastewater treatment sludge comes up to 1.3 million tons per year. A stunning amount of wet manure coming from the Dutch agricultural industry accounts for up to 71 million tons per year.    

Incineration of these residues require a lot of extra energy and subsequent emissions, due to the wet nature of these streams. Valuable components and materials are also lost. Or can only be converted into unwanted electricity, of which buffering is very difficult or costly.   

Steps to take

A first step was to recognise the potential of super critical water technology on industrial scale. The project’s main objective is to prove that the technology is actually able to process specific wet streams. Testing in a continuous lab installation should provide these insights. This step will also identify how individual streams can be treated. While preserving the building blocks.  

We aim to enable a data driven decision on the full-scale commercial processing of individual waste streams. The project intends to act as the precursor for a more elaborate program, towards a much wider application field in areas of other wet waste streams.   

Project activities 

Stream owner(s) will carry out an analysis of a set of waste streams. SCW Systems will design and build the new bench scale test reactor, required pre-treatment installation based on the composition of the streams and the syngas and water treatment. 

Moreover, the consortium partners will define the requirements for additional analyses to enable a data driven compact life cycle analysis and/or assessment of the results obtained. They do so, in order to come to a decision in the full-scale commercial processing of individual waste streams.  

The tests performed will be iterative in nature. They aim to scan the operating window and determine the optimum set of operating parameters. This applies to all 3 sequential processing steps: pre-treatment and mixing, conversion, syngas and water treatment. The objectives and high-level results of the project will be disseminated and used for an extensive program to be set up with a positive outcome.  

For more information on the SCISSORS-project.