Description
In most urban communities around the world, human waste from toilets is collected in sewer lines and pumped to a nearby municipal wastewater treatment plant. Wastewater treatment yields treated water, which is clean enough to be discharged and re-join the natural water cycle. The solid leftover from wastewater treatment is sewage sludge.
Cambi provides solutions for the sustainable management of this sludge. Cambi’s core technology is the Thermal Hydrolysis Process (CambiTHP®), which exposes sewage sludge to high temperature and pressure.
Cambi’s technology has been recently implemented in the Netherlands. The Tilburg “Energy Factory” in the Netherlands was constructed as part of an ambitious Dutch national strategy to exploit the resources of wastewater and generate green electricity. Cambi’s thermal hydrolysis process has significantly contributed to increase production of clean, green energy, in line with the Dutch sustainability goals
Added value
- The use of Thermal Hydrolysis prior to anaerobic digestion results in a tripling of digester capacity, by allowing higher feed concentrations and lower residence times. The Tilburg plant was converted into a regional sludge centre, efficiently treating all the sludge produced in the area managed by Water Authority De Dommel
- Thermal Hydrolysis strongly improves the dewaterability of sludge thereby reducing the amount of treated product that needs to be disposed of
- Thermal hydrolysis has helped to increase biogas production, covering the plant’s energy demand, with surplus biogas upgraded and exported to the gas grid
- Energy is also saved due to reduction of the volume of final biosolids sent to the sludge mono-incinerator
Challenges
- Limited space and high costs to build several wastewater treatment plants with advanced digestion. Tilburg WWTP purifies the wastewater from the city of Tilburg and surrounding areas. De Dommel water authority also operates a large 750 000 PE WWTP in Eindhoven with no possibility for local sludge digestion. A plan was developed therefore to create a centralised Resource Recovery Facility at the Tilburg site to centralise all sludge treatment in one advanced digestion facility using Cambi’s thermal hydrolysis process
- The Dutch market which struggles with a limited disposal market and high disposal cost
- Public tender regulation and lack of specialised know-how about the specific technology in the country
Partners
The overall project was executed by general contractor Heijmans Civiel, with Cambi as subcontractor for the Thermal Hydrolysis technology.