Treatment for wastewater sludge through bio-based processes
66% of the world’s population's (4.5 billion) wastewater are being collected and treated. The growing environmental awareness brings governments to set ambitious goals towards 100% population connected to decent wastewater treatment. It is vital to find a solution for treating the huge amounts of sludge from wastewater, making it less harmful to human health, whilst reducing the process’s energy-intensity. Applied CleanTech’s SRS system PREVENT sludge rather than treat it, while reducing electricity usage & energy consumption and producing the RecylloseTM (recycled cellulose) that have a commercial value in numerous industries.
The challenge
Sludge treatment and recovery of wastewater is an important issue, in order to reduce environmental impact as well as human health risks, whilst at the same time reducing costs. The challenge is in looking at these solids not as waste, but as a resource and base for raw materials, as the current solutions only deal with for preventing reducing sludge volume, and not preventing its formation.
The innovation
The challenge was recognized by Dr. Refael Aharon, CEO & Founder of the company Applied CleanTech (Israel), when looking for alternative source of cellulose. Applied CleanTech patented SRS technology traps the cellulose components in raw wastewater and processes them into a clean, pasteurized, environmentally friendly product - Recyllose™ - a valuable resource that can be used in plastics, insulation, pulp & paper, construction, bio-fuels production as well as additional industries. The project had a private equity funding for development, demonstration and commercial exploitation.
The solution was the innovative Sewage Recycling System (SRS). SRS can be added to existing or new wastewater treatment plants (WWTP), reducing sludge formation in wastewater by up to 50%. The SRS technology enables sewage solids from industrial and municipal WWTPs to be fully and automatically converted into a high quality, pasteurized product, before they become sludge. The process decreases the use of electricity & energy consumption, compared to conventional WWTP.
The process starts with raw sewage, which has grit filtered out, and is pumped into the SRS which cleans it even more by filtrating additional grit. The wastewater then passes through a multi-stage trapping process that removes cellulose and other materials by mechanical filtration. The material considered undesirable is separated. The remaining wastewater is then returned to the WWTP to continue the biological or chemical treatment used by the WWTP. The SRS technology is complementary to current treatments used by the WWTP. As the amount of larger particles has been reduced and the sludge composition is lacking the hard-to-digest particles, the biological treatment process is much more efficient, as well as cost effective. It also reduces the need for cleaning and maintenance when smaller amounts of sludge reach the various process steps in water and wastewater treatment.
The filtered cellulose, which forms RecylloseTM, proceeds to a process stage heating, pasteurizing and processing it to 90% dry matter. The stage uses the heat produced within the system. RecylloseTM is dried and converted into pellets. RecylloseTM is a material that can be used as a renewable energy source, as an additive in the paper and plastics industries, as an additive to construction and insulation products, as a resource for production of Nano-Cellulose, as well as additional industries.
Recent case study in the Netherlands about the WWTP as a raw material factory for the production of RecylloseTM proved the innovation and in the importance of the SRS technology, as well as the great commercial potential of the RecylloseTM as a raw material that can be used in numerous industries.
Operating expenses for SRS can be reduced by 30% through reduced electricity & energy consumption. In addition, the capacity of a plant can be increased by 30%, whilst the lifetime is extended. Reduced energy consumption, less chemicals and sludge not only creates less maintenance and need for time and resources, but also a reduced carbon footprint.
Why did it work?
Driven by his passion of taking ideas and creating successful businesses, Dr. Refael Aharon founded Applied CleanTech in 2007.
Further deployment
The SRS technology is approaching 9 on the TRL scale, as it has been successfully deployed world-wide. The technology is currently used in Israel, Mexico, the Netherlands, and Scotland and Applied CleanTech is now looking for additional business partners, as well as investments.
Links:
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