DESIGN OF CITY SCALE FECAL SLUDGE TREATMENT PLANT (FSTP) IN SUKABUMI REGENCY

• Main Author: Kusumayanti, Intan
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/54496
• Institution: Institut Teknologi Bandung

Sukabumi Regency is the largest district in West Java Province with an area of 5011.30 km2 and in 2018 it has a population of 2,551,440 people (BPS, 2019). The domestic wastewater management system in Sukabumi Regency is not good. There are still people who practice defecation with a percentage of 18.06%, 22.47% of the people are served by goose-neck latrines and sitting / squat toilets that are not equipped with septic tanks (still using cubluk) and sitting / squat toilets using septic tanks that are not in accordance with SNI 03-2398-2002 standards, 59.47% of the people are served by sitting / squat toilets using a standardized septic tank, and 0% of the people are served by sitting / squatting toilets using a septic tank that is in accordance with the standard and sludge and effluent of septic tank is further treated before discharge to the environment. Until now, Sukabumi Regency has not issued a Regional Regulation concerning Management of Settlement Wastewater in detail, the related macro regulations are contained in Regional Regulation Number 22 of 2012 concerning the 2012-2032 Regional Spatial Plan of Sukabumi Regency. Funding for the domestic wastewater sector in Sukabumi District comes from the Central Government, Regional Governments (Provinces and Districts), and loans. There is no special institution that deals with wastewater management in Sukabumi Regency. Domestic waste management institutions in Sukabumi Regency are still carried out by the local government in this case the Regional Development Planning Agency (BAPPEDA), the Department of Land and Spatial Planning (DPTR), the Office of Housing, Settlements and Cleanliness (Perkimsih) and the Environmental Service (DLH) and the Public Works Office (PU) of Sukabumi Regency. In addition, in Sukabumi District, a Sukabumi District Sanitation Working Group (POKJA) has also been formed. Based on data from the Environmental Service Office of Sukabumi Regency, there is an FSTP location which is located in Sukamulya Village, Cikembar District, Sukabumi Regency. The feasibility analysis of the FSTP location was carried out based on the criteria for selecting the FSTP location in the Main Book of the Detailed Engineering Planning Guidelines for Fecal Sludge Treatment Plants (FSTP). The criteria for selecting the FSTP location include the distance to the service area, the slope of the FSTP land, the travel time for the FSTP to the farthest service area, the type of land use according to the RTRW, the distance to the receiving water body, land legality, regional administrative boundaries, and type of land. Based on the analysis, the score was 221 (the FSTP location was acceptable). The FSTP of Sukabumi Regency is prioritized to serve 23 Districts located in the northern part of Sukabumi Regency. In the planning of FSTP in Sukabumi Regency, a 20-year design period was chosen which would be divided into 2 phases, namely Period I (2023-2033) and Period II (2033-2043). The quantity of sludge treated in the Regency FSTP is the result of multiplying the rate of sludge generation with the projected population, the percentage of septic tank use and the percentage of FSTP services. The generation of sludge that will be treated in the FSTP of Sukabumi Regency Period I and II is 154 m3 /day and 279 m3 /day, respectively. The influent characteristics of the planning fecal sludge had values of TSS 13068 mg/L, COD 16911 mg/L, BOD 1525 mg/L, ammonia 217 mg/L, total Kjeldahl nitrogen 618 mg/L, oil and fat 208 mg/L, and total coliform. 9.3 × 109 MPN/100 mL. Because until now there has been no set quality standard for treated water (effluent) in FSTP, the Minister of Environment and Forestry of the Republic of Indonesia Regulation Number 68 of 2016 concerning Domestic Wastewater Quality Standards will be used as a reference for quality standards. In planning the FSTP of Sukabumi Regency, three alternative configuration treatment were proposed. Five aspects were chosen to be used as the selection criteria for alternative selection. These aspects are land requirements, investment costs, efficiency, ease of operation and maintenance, and sludge disposal. By using the simple additive weighting method, alternative 1 is obtained as the selected system with the highest score of 74.58. The selected series of treatment system consist of bar screen, dumping station, solid separating chamber (SSC), drying area, anaerobic baffled reactor (ABR), aerated lagoon, sedimentation pond, coagulation, flocculation, sedimentation, disinfection, and sludge drying bed. . The estimated investment cost for the FSTP’s construction for Period I is IDR 40,132,729,979 and for Period II is IDR 22,131,232,287. The total cost of operation and maintenance of FSTP in Sukabumi Regency for Period I was Rp. 7,658,704,124 and for Period II was Rp. 11,683,626,996. Based on the economic analysis carried out, the construction of FSTP in Sukabumi Regency Period I and II had a NPV value of IDR 179,074,380,359 and respectively.