Investigasi Eksperimental Dan Simulasi CFD Pengurangan TSS Pada Bak Prasedimentasi Untuk Pengolahan Air Baku Instalasi Penjernihan Air Kota Surabaya

Arilina, Arilina (2026) Investigasi Eksperimental Dan Simulasi CFD Pengurangan TSS Pada Bak Prasedimentasi Untuk Pengolahan Air Baku Instalasi Penjernihan Air Kota Surabaya. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5014221045_Undergraduate_Thesis.pdf Restricted to Repository staff only Download (8MB) | Request a copy

Abstract

Pertumbuhan populasi dan aktivitas ekonomi masyarakat meningkatkan beban polusi air sungai sehingga menurunkan kualitas air baku. Instalasi Pengolahan Air (IPA) dituntut adaptif terhadap perubahan debit dan fluktuasi kualitas air baku. Unit prasedimentasi memegang peranan krusial dalam pengolahan air baku, namun efisiensinya sangat dipengaruhi oleh kondisi operasional, pola aliran, dan karakteristik pengendapan partikel. Penelitian ini mengevaluasi efisiensi penyisihan Total Suspended Solids (TSS) pada reaktor prasedimentasi skala laboratorium hasil scale down IPAM Karangpilang III, Kota Surabaya menggunakan pendekatan eksperimental dan simulasi Computational Fluid Dynamics (CFD). Variabel bebas penelitian meliputi konsentrasi TSS influen (sampel buatan dengan TSS ±400 mg/L dan air baku IPAM Karangpilang III dengan TSS ±752 mg/L) sebagai representasi perubahan kualitas air baku, waktu tinggal hidraulik (1,43; 2; dan 4 jam) sebagai representasi perubahan debit pengolahan, dan konfigurasi sekat (tanpa baffle, baffle non-perforated, dan perforated baffle) sebagai representasi respons geometri unit prasedimentasi. Variabel terikat yang diukur adalah konsentrasi TSS, kekeruhan, dan kecepatan aliran, dengan dimensi serta geometri reaktor sebagai variabel kontrol. Hasil penelitian menunjukkan bahwa kompleksitas hidrodinamika reaktor, seperti short-circuiting, zona mati, dan arus balik, terbukti akurat dan tervalidasi melalui simulasi CFD yang ditinjau dari kontur kecepatan dan profil kehilangan tekanan. Kontur kecepatan hasil simulasi CFD pada waktu detensi 2 jam dan 4 jam tidak memberikan perbedaan besar. Penyisihan TSS eksperimental dengan Td 2 jam dan 4 jam tidak memberikan perbedaan besar berdasarkan uji statistik. Kondisi operasi optimum reaktor prasedimentasi dicapai pada Td 2 jam dengan konfigurasi baffle non-perforated, dengan efisiensi penyisihan TSS secara eksperimental sebesar 88,24% (sampel buatan, TSS ±400 mg/L) dan 96,14% (sampel air baku IPAM Karangpilang III, TSS ±752 mg/L), serta secara simulasi CFD sebesar 87,11% dan 85,63%. Secara hidrolis, konfigurasi ini mencapai keseimbangan terbaik antara distribusi aliran yang seragam, pencegahan pecahnya flok akibat gaya geser tinggi pada Td 1,43 jam, dan pencegahan resuspensi sedimen pada Td 4 jam. Temuan ini menegaskan bahwa baffle non-perforated pada Td 2 jam memaksimalkan kinerja prasedimentasi, terutama pada beban polutan tinggi, sekaligus menyediakan alat evaluasi berbasis simulasi CFD yang adaptif terhadap fluktuasi operasional di lapangan. ==================================================================================================================================
Population growth and increasing economic activity have intensified river pollution, leading to a decline in raw water quality. Water Treatment Plants (WTPs) are required to be adaptive to fluctuations in both discharge and raw water quality. The pre-sedimentation unit plays a crucial role in raw water treatment; however, its efficiency is significantly influenced by operational conditions, flow patterns, and particle settling characteristics. This study evaluates the Total Suspended Solids (TSS) removal efficiency of a laboratory-scale pre-sedimentation reactor, designed as a 1:70 scale-down of the Karangpilang III WTP in Surabaya, using an integrated experimental approach and Computational Fluid Dynamics (CFD) simulation. The independent variables included influent TSS concentrations (synthetic samples of ±400 mg/L and actual raw water from IPAM Karangpilang III at ±752 mg/L), hydraulic retention times (Td: 1.43, 2, and 4 hours), and baffle configurations (none, non-perforated, and perforated) to represent the geometric response of the unit. The dependent variables measured were TSS concentration, turbidity, and flow velocity, while the reactor's dimensions and geometry were kept as control variables. The research results show that the hydrodynamic complexities of the reactor, such as short-circuiting, dead zones and backflow, were found to be accurate and validated through CFD simulations, as assessed from velocity contours and pressure loss profiles. The velocity contours from the CFD simulations at detention times of 2 hours and 4 hours did not show any significant differences. The experimental TSS removal at detention times of 2 hours and 4 hours did not show significant differences based on statistical tests. Optimum operating conditions for the pre-sedimentation reactor were achieved at a retention time (Td) of 2 hours with a nonperforated baffle configuration, with an experimentally determined TSS removal efficiency of 88.24% (artificial sample, TSS ±400 mg/L) and 96.14% (raw water sample from the Karangpilang III Water Treatment Plant, TSS ±752 mg/L), and CFD simulation values of 87.11% and 85.63%. Hydraulically, this configuration achieves the optimal balance between uniform flow distribution, prevention of floc break-up due to high shear stress at a retention time (Td) of 1.43 hours, and prevention of sediment resuspension at a Td of 4 hours. These findings confirm that a non-perforated baffle at a Td of 2 hours maximises pre-sedimentation performance, particularly under high pollutant loads, whilst providing a CFD-based evaluation tool that is adaptable to operational fluctuations in the field.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Baffle, Computational Fluid Dynamics, Prasedimentasi, Total Suspended Solids, Waktu Tinggal Hidraulik Baffle, Computational Fluid Dynamics, Hydraulic Retention Time, Pre-sedimentation, Total Suspended Solids
Subjects:	T Technology > TD Environmental technology. Sanitary engineering > TD433 Water treatment plants
Divisions:	Faculty of Civil Engineering and Planning > Environment Engineering > 25201-(S1) Undergraduate Thesis
Depositing User:	Arilina Arilina
Date Deposited:	24 Jul 2026 06:44
Last Modified:	05 Aug 2026 02:17
URI:	http://repository.its.ac.id/id/eprint/137156

Actions (login required)

View Item