Rural Community Wastewater Sludge – Resource Recycling Facility (Introduced to: A local government)
|Processed Material and Amount||Sludge, 5 tons/week|
|Overview||A composting facility was built for the purpose of reducing the cost of processing rural community wastewater sludge, and using it for regional recycling.|
Measures and Effects
|Reduce foul odors||By mixing sludge with a pre-processing device that eliminates sludge clumps and suppresses anaerobic fermentation, they stopped generation of foul odors.|
|Raise fermentation temperature||At the start of fermentation, the sludge is heated with a small amount of hot air, raising the fermentation temperature faster.|
|Reduce cost||It is designed to operate with the minimum number of workers, by automating the mixing of sludge with auxiliary materials (preparation work).|
|Improve compost quality||By mixing with a pre-processing device, sludge clumps are eliminated and by sustaining aerobic fermentation, high fermentation temperature is achieved and compost quality is improved.|
In H City, there is a population of 6,000 in District M, the target area of this facility.
Household wastewater in this area is processed at eight rural community wastewater facilities.
A mobile dehydration vehicle travels to these 8 processing facilities, and brings dehydrated cakes (1 ton/day) to the resource recycling (composting) facility.
We delivered a C-Mode system to the composting facility. Dehydrated cakes brought to the facility are mixed with rice husks using C-Mode, then deposited and composted.
After fermentation is finished, the compost is dried to remove excess moisture, and most of it is reused as return compost.
Assuming 100 cakes are carried in, about 85 will be recycled as return compost, and about 15 cakes are shipped as compost.
When the deposited processed material is dug up, it becomes very hot and produces a lot of steam. It is clear that there is still sludge at the start of fermentation, and decomposition progresses for several days, so that sludge becomes almost invisible in the final drying stage. Some of the compost made this way is used as return compost.
In the final process, materials are put in an aeration drying tank in order to evaporate any moisture, and the finished compost is reused as return compost.
This makes it possible to reduce the cost of procuring auxiliary materials and adjust the amount of compost shipment.