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SITC of Treated Water Tank A 2000-liter High-Density Polyethylene (HDPE) treated water storage tank is designed to store reclaimed water from STPs for reuse in flushing, gardening, or irrigation. Constructed using PE100 grade, UV-stabilized HDPE, it offers excellent resistance to corrosion, weathering, and residual treatment chemicals. The tank is rotationally molded with a minimum wall thickness of 10–12 mm, ensuring structural integrity and durability. It includes a manhole with cover, inlet/outlet nozzles, vent pipe, and overflow provision. The tank conforms to IS 15908:2011 for HDPE tanks and is suitable for both indoor and outdoor installation. Easy to install, transport, and maintain.

Air Blowers SITC of Air Blowers: - Quantity: 2 Nos (1 working + 1 standby) - Types: Regenerative air blower, turbine blower, twin lobe blower - Capacity: 100 cubic meters per hour - Pressure: 0.5 kg/cm² - Material: Cast Iron (CI) - Function: Supplies air for aeration in the biological treatment process.

Submersible Pumps SITC of Raw Sewage Lifting Pump: Submersible non-clog sewage pump with cast iron body and stainless-steel impeller, IP68 rated, operates at 415V three-phase power. Delivers 10–20 m³/h flow at 7–12 m head. Suitable for continuous duty with thermal overload protection. Conforms to IS 8034:2018 standards for submersible sewage pumps. - Quantity: 2 Nos (1 working + 1 standby) - Material: Cast Iron (CI) casing, Carbon Steel (CS) shaft - Function: Pumps sewage from the collection tank into the treatment plant.

Sludge Recirculation Pump SITC of Sludge Recirculation/Transfer Pump: Sludge recirculation pump is a non-clog centrifugal or submersible unit for transferring thickened sludge in STPs. Rated 1.5–3 HP, it delivers 10–15 m³/h at 8–10 m head. IP68 rated, with abrasion-resistant impeller. Conforms to IS 8034:2018. - Quantity: 1 No. - Material: CI casing and impeller, CS shaft - Function: Recirculates and transfers sludge.

Diffused Aeration System SITC of Coarse and Fine Air Diffusers: A diffused aeration system is essential in MBBR-based STPs for efficient oxygen transfer and mixing. It consists of fine bubble diffusers (EPDM/silicone membrane), mounted on SS-304 or UPVC pipelines connected to a twin-lobe air blower. Each diffuser handles 2–5 m³/h air and covers 1–1.5 m² area. The system conforms to IS 15322 for design and material standards. - Coarse Diffuser: EPDM, 150 mm diameter - Fine Diffuser: EPDM, 65 mm x 620 mm - Function: Distributes air in the aeration tank to promote bacterial growth.

SITC of MBBR Media (Bio-carriers) MBBR (Moving Bed Biofilm Reactor) bio media are specially designed plastic carriers used in aeration tanks to support biomass growth and enhance biological treatment. Made from virgin polypropylene (PP) or HDPE, these media are UV stabilized, non-toxic, and have high surface area (350–800 m²/m³) to promote microbial colonization. They are cylindrical or disc-shaped with internal fins to ensure high contact efficiency and turbulence. Surface Area: 400 m²/m³ - Function: Provides a surface for biofilm growth, aiding in sewage treatment.

SITC of Tube Deck Media: Tube deck media, also known as lamella clarifier media, is used in the settling tank of STPs to enhance solid-liquid separation efficiency by increasing the effective surface area for sedimentation. It is made of PVC or PP with high structural strength and chemical resistance. The media consists of hexagonal or rectangular tubes, inclined at 60°, promoting efficient settling by reducing particle settling distance. - Loading Rate: 1.5 cum/hr/sqm - Function: Enhances the settling of solids.

SITC of Filter Feed Pump: A filter feed pump is used in an STP to transfer treated water from the secondary clarifier or aeration tank to the tertiary filtration system, such as a pressure sand or activated carbon filter. Constructed with a cast iron casing and stainless steel impeller, the pump is energy-efficient, corrosion-resistant, and suitable for continuous operation. It complies with IS 6595 (Part 1):2002 for centrifugal pumps. - Quantity: 2 Nos (1 working + 1 standby) - Capacity: 5.0 cubic meters per hour - Material: CI casing, CS shaft - Function: Pumps treated water to the filters.

SITC of Multi-Grade Sand Filter: A Multigrade Sand Filter (MGF) is used in STPs for tertiary treatment by removing suspended solids, turbidity, and residual organic matter from treated sewage. It comprises a vertical/horizontal pressure vessel filled with layers of graded media: coarse gravel, fine sand, and pebbles. The vessel is typically made of MS rubber-lined material, with internal piping in SS or PVC. Operating pressure ranges between 2.5–4 kg/cm², Conforms to IS 7389. - Capacity: 2.5 cubic meters per hour - Function: Removes suspended particulate matter.

SITC of Activated Carbon Filter: An Activated Carbon Filter (ACF) is used in STPs for tertiary treatment to remove odor, color, chlorine, and trace organic contaminants from the treated sewage before discharge or reuse. It consists of a pressure vessel (FRP or MSRL), filled with granular activated carbon (GAC) derived from coconut shell or coal-based sources. The filter operates at a pressure of 2.5–4 kg/cm² Internal piping is of UPVC or SS. Conforms to IS 877:1994. - Capacity: 2.5 cubic meters per hour - Material: FRP - Function: Removes odor, color, and residual organic matter.

SITC of Chlorine Dosing System: A chlorination dosing system is installed in STPs to disinfect treated wastewater before final discharge or reuse. It includes a dosing pump, HDPE/PP chemical tank (100–200 liters), suction/discharge piping, NRVs, and control panel. The dosing pump is usually solenoid or motor-driven, capable of delivering 0–6 LPH at 3–5 bar pressure, ensuring accurate hypochlorite solution injection. Tanks and piping are chemical-resistant, and the system operates in both manual and automatic modes. It complies with IS 8438:1994 for dosing equipment. - Capacity: 0-6 LPH - Function: Disinfection by dosing hypochlorite solution.

SITC of . Sludge Feed Pump: A sludge feed pump is used in STPs to transfer settled sludge from clarifiers or sludge tanks to sludge dewatering systems like filter presses or drying beds. It is a progressive cavity or non-clog centrifugal pump, designed to handle high-viscosity, semi-solid materials without clogging. The pump body is constructed from cast iron or stainless steel, with abrasion-resistant impellers or rotors. The pump conforms to IS 5120. - Quantity: 1 No. - Capacity: 2 cubic meters per hour - Material: SS/CI construction - Function: Transfers sludge to the filter press.

SITC of Filter Press: A 15-plate filter press functions by pumping sludge under pressure into a series of 15 polypropylene plates, each lined with durable filter cloths. As the sludge enters, solids are trapped between the plates while water is expelled through side drain ports, significantly reducing the moisture content. The system operates at 4–6 bar pressure and is equipped with a semi-automatic hydraulic mechanism for plate compression and release. Typical sludge handling capacity is 400–600 liters per cycle, depending on the solids concentration. Built using a mild steel frame with anti-corrosive epoxy coating, the press is designed for long operational life and low maintenance. The unit conforms to IS 14254 standards for mechanical dewatering equipment. The filter press is installed under a protective shed to shield it from weather and contamination. A 4 m x 4 m shed with a steel frame, GI roofing, concrete flooring, and a basic drainage and electrical setup ensures safe and continuous operation.

SITC of Control Panel (MCC) The control panel in a 100 KLD STP is the central unit that manages the operation of pumps, blowers, dosing systems, and other equipment. It is fabricated from powder-coated CRCA sheet steel with an IP54/IP65 protection rating, ensuring durability and safety. The panel includes MCBs, contactors, relays, digital meters, timers, and optionally a PLC or VFD for automation and energy efficiency. It ensures safe start/stop sequences, overload protection, and real-time monitoring. Compliant with IS 8623 and IS 13947, it is essential for uninterrupted, safe plant operation.

Armoured power cabling in a 100 KLD STP ensures safe electrical distribution to equipment like pumps, blowers, and control panels. These are 1.1 kV grade XLPE-insulated, steel wire armoured cables, complying with IS 7098 (Part 1) and laid per IS 1255. Sisez as follows: Blowers: 6 sq.mm, Feed Pumps: 6 sq.mm, Sludge Pump: 4 sq.mm, Filter Feed Pump: 6 sq.mm, Control Panel Incoming: 25 sq.mm.

Earthing System The chemical earthing system in a 100 KLD STP ensures long-lasting and low-resistance grounding. It includes 4 nos. maintenance-free chemical earthing electrodes, each 3 meters long, 50 mm dia (GI or copper-bonded rod) filled with bentonite or graphite-based compound, as per IS 3043 and IEC 62561. Each pit uses an Earth Enhancement Compound (25 kg/bag) to reduce soil resistivity. The electrodes are connected via 25x3 mm GI strip, about 20 meters total. Resistance is maintained below 1 ohm.

Piping & Valves (Interconnecting) The STP uses a network of HDPE or UPVC pipes for treated, raw, and sludge water conveyance. Butterfly valves (ISI-marked) and non-return valves (NRVs) are installed at pump discharge lines and process units, ensuring control and backflow prevention. All pipes and valves comply with IS 4984 (HDPE) and IS 778 (valves).

A 100 KLD STP typically includes key instruments for process monitoring and control: Digital pH Meter (IS 3025 Part 11): Measures acidity/alkalinity; range: 0–14; quantity: 1 DO Meter (IS 3025 Part 38): Measures dissolved oxygen in aeration tanks; range: 0–20 mg/L; quantity: 1 Ultrasonic Level Transmitters: Monitor water/sludge levels in tanks; range: 0–5 meters; quantity: 3