Suzhou Industrial Park sludge treatment project, source recycling model
Sludge is the inevitable by-product generated during wastewater treatment process. It is usually in large volume, perishable, smelly and contains heavy metal, germs and hazardous components. It can seriously pollute the water body, soil, underground water and air, as well as impact the human health, if discharged to the environment without scientific treatment. Therefore, we must make it harmless, reduce and recycle, to avoid the secondary pollution.
Safe and Efficient INNODRY 2E® Process
Industry Synergy and Circular Economy
The sludge drying plant is located close to the co-generation plant, wastewater treatment plant. Through the synergy between the three plants, it really archives the concept of resource recycling.
Between Wastewater Treatment Plant and Sludge Drying Plant
- The wet sludge of the Wastewater Plant is sent to the sludge drying plant for treatment;
- The cooling water used during the sludge drying process is the reclaimed water from the wastewater plant.
Between Sludge Drying Plant and the Co-generation Plant
- The excess heat from the co-generation plant is supplied to the sludge plant in the form of steam to dry sludge;
- The dried sludge is reused as fuel to be burned in the co-generation plant;
- The condensate generated during sludge drying process is sent to the co-generation plant as boiler water.
Through the advanced INNODRY 2E® process from SUEZ as well as the industrial synergy, the sludge project in SIP turns the sludge, the by-product of WWTP to resources, which is a perfect example of circular economy.
In SIP, the dry sludge after treatment is sent to the power station, as an alternative fuel, allowing to save about 24,000 tons standard coal and lowering CO2 emissions. It is estimated that 100,000 tons of sludge can generate energy equivalent to 6,000 tons of fuel oil.
The condensate generated during the sludge drying process is sent back to the power station to be reused for the boilers, which can save around 136,000 tons desalted water per year.
Bottom ash resulting from the incineration process is used by another industrialist in the park to produce cement, realizing the zero discharge of sludge disposal reducing by 20,000 tons of solid waste generated.
Low energy consumption
This advanced drying technology with low energy consumption and high level safety and environment protection consume 40% less energy than the normal sludge drying process due to the cascade utilization of energy.