Decentralised Waste Water Treatment > Case Studies

Centralized Sludge Treatment Facility (CSTF), Sungai Udang, Malaysia

Site visit done by: Sumit Kumar Gautam, Naveen Kumar, Ridhima Gupta 

Date of visit: 9 August, 2017

Scale of service: (Melaka Tengah and Western of Alor Gajah) 300,000 PE
Inlet: Sludge from OSS and clarifiers
Operational since: 2008
Treatment capacity: 250 m3/ day

 Area: 11.4 Ha
Outlet/end products: Effluent in Sg. Ayer Batu river and Dried sludge in trenching site
Opex of the plant: 200,000 RM per annum (INR 32,00,000)
Sludge treatment time (approx.): 8 hrs
 
 
This centralised sludge treatment facility is highly mechanised plant as 50% of the opex is towards the electricity bills (equipped with 119 pumps). The plant treats the fecal sludge removed from septic tanks and also sludge from small sewage treatment plants. The plant dpeloys 3 feed steps biological scrubbers to remove the odour. The sludge is thickened to at least 20% dried sludge in dewatering units (mechanical compressors) after mixing the polymers and coagulants to enhance the solid recovery.
 
 

As shown in below schematics, the tankered sludge is first passed through two coarse screens. The scum collection tank removes any oil and grease which is pumped to sand bed. The screened sludge is temporarily stored in sludge holding tank.

Prior to discharging the sludge into dewatering units, the sludge is mixed with polymers to enhance the solid recovery. Finally the sludge is dewatered to at least 20% dried sludge in mechanical thickeners (centrifuge that are operated in 8 hrs shift, three times a week). The dried sludge is transported to sludge yard using sludge hoppers and finally disposed into trenching/land fill sites.

The reduction in BOD, Nitrogen and SS in effluent is achieved through 2 step anoxid-aerobic processes (a total of tanks in series). While the anoxic tanks are equipped with submersible mixers, aerobic tanks have fine bubble diffusers. The sludge from clarifier is transferred to sludge holding tanks where it is processed along with tankered sludge.
 
 
The system is expected to provide treated water that would be used for horticulture purposes to maintain green area of 0.5 Acres. This would help in saving about 8000 litres of fresh water. Water quality report at the inlet and outlet of the DWWTs will be furnished in due course.
 
 

Mr. James Oliver Warren
Indah Water Konsortium (IWK)
Melaka Unit office.
Tel: 06 317 5209/ 3561
Email: care@iwk.com.my

 

Tags: Malaysia, Sewage Treatment Plants (STP),