Trout Run Sewage Treatment Plant — Photo: Montgomery County Planning Commission

Port Washington Sewage Treatment Plant — Photo: Brett VA

Hyperion Sewage Treatment Plant — Photo: Mozul

Representative photos. Your order is sourced to your specification from verified sellers. Photos: “Trout Run Sewage Treatment Plant II” by Montgomery County Planning Commission, CC BY-SA 2.0; “Trout Run Sewage Treatment Plant” by Montgomery County Planning Commission, CC BY-SA 2.0; “Port Washington Sewage Treatment Plant” by Brett VA, CC BY 2.0; “Hyperion Sewage Treatment Plant” by Mozul, CC BY-SA 2.0.

Water and wastewater

STP supplier in Bangladesh

Roptan acts as your STP supplier in Bangladesh. Send us the daily flow, the number of users and where the treated water goes, and we source a packaged or site-built sewage treatment plant from verified sellers, check its design basis and deliver it.

Verified sellers
Checked before it ships
Delivered by Roptan

Prefer to deal with suppliers yourself? Post it on the requirement board

STP products

Pick a product and we source it for you, or send one requirement that covers several.

Photo soonPackaged STPFactory built, ready to connectGet it sourced

Photo soonContainerised STPBuilt inside a shipping containerGet it sourced

Photo soonMBBR STPCompact biofilm processGet it sourced

Photo soonSBR STPBatch treatment in one tankGet it sourced

Photo soonSludge free STPLess sludge, never zeroGet it sourced

On site built STPConcrete tanks, long lifeGet it sourced

Buying STP in Bangladesh

A sewage treatment plant (STP) treats toilet, kitchen and washroom wastewater so it can go to a drain or canal, or back into use for flushing and gardening. Most buildings in Bangladesh have no sewer connection, so developers, hospitals, hotels and schools in Dhaka, and factories in Gazipur, Narayanganj and Chattogram (Chittagong), install their own to meet the ECR 2023 limits the Department of Environment enforces. Choosing an STP supplier in Bangladesh starts with your load, not a brochure.

You send the requirement once. We shortlist verified sellers, have them design to the same flow and outlet limits, compare process, power draw and scope line by line, and check licences, reference plants and warranty terms. We deliver the plant with its documents; the seller installs, seeds and commissions it. To deal with sellers yourself, post the requirement on our board.

STP we source

Packaged STP

A prefabricated plant in FRP (fibre reinforced plastic), coated mild steel or stainless steel tanks, set on a concrete slab. Choose it for apartment buildings, hotels, hospitals and factories with small to medium flows, where civil work must be short.

Containerised STP

Tanks, blowers and control panel fitted inside a 20 or 40 foot container, piped, wired and wet tested before dispatch. It suits construction camps, temporary sites and leased land, needs only a level base, and can be lifted out and moved.

MBBR STP

A moving bed biofilm reactor grows bacteria on plastic carriers that move freely in an aerated tank, so the tank is smaller for the same load. It suits tight Dhaka plots and flows that swing through the day. Compare blower power in kW.

SBR STP

A sequencing batch reactor fills, aerates, settles and decants in one tank on a timed cycle. It handles uneven flow and can be run to remove nitrogen, but it relies on its controller, level sensors and decanter.

Sludge free STP

Sold on producing little or no sludge. Long aeration or added bacterial cultures break down more of the solids, so desludging is needed less often. Every biological plant still makes some sludge, so get the expected quantity and interval in writing.

On site built STP

Reinforced concrete tanks cast at your site, then the seller fits blowers, diffusers, pumps and the panel. It suits large flows and new buildings with a plant room designed in. Each tank needs a water tightness test.

How to specify a sewage treatment plant

Daily and peak flow: State average flow in m³ per day and the peak hour. If you only know the number of users, give that with the building use. Sewage arrives in peaks, and the tanks must absorb them.
Inlet quality: Give BOD, COD, TSS, pH and oil and grease from a lab report, or let the seller write assumed values into the design basis. Kitchens and canteens need a grease trap first.
Outlet and reuse: Say where treated water goes: drain, canal or reuse for flushing and gardening. Reuse adds filtration, disinfection, a treated water tank and a separate pipe line.
Space and access: In Dhaka buildings the plant often sits under a car park. Give dimensions, clear height, crane access and a route for lifting out blowers.
Power and load shedding: Aeration cannot stop for hours or the plant turns septic and smells. Ask for duty and standby blowers on the generator circuit, with phase failure protection and automatic restart.
Flood level and groundwater: Keep blowers and panels above the highest flood level. Buried tanks need anchoring or ballast so they cannot float when emptied while groundwater is high.
Stormwater and scope: Roof and yard drains must not join the sewage line, or monsoon rain washes the bacteria out. Ask for civil work, commissioning and a service period as separate lines.

Standards and tests to ask an STP supplier in Bangladesh for

ECR 2023 and DoE clearance: The Environment Conservation Rules 2023 set the discharge limits. Ask the seller to state them in the design basis and supply the design report your Department of Environment clearance file needs.
BNBC 2020: The Bangladesh National Building Code 2020 covers structural design and plumbing. A plant inside a building needs the structural engineer's sign-off on slab loads.
Concrete tank tightness test: For tanks built on site, ask for a water tightness test on each tank before equipment is fixed, for example to ACI 350.1, and keep the record in the handover file.
Accredited lab performance test: Once the biology has settled, inlet and outlet samples taken on several days are tested at an ISO/IEC 17025 accredited lab for BOD, COD, TSS, pH and oil and grease. BOD results take five days.

What moves the price of an STP

Design flow and peak: a plant sized for the peak hour costs more than one sized for the daily average, and inlet strength sets tank volume and blower size.
Tank material: FRP, coated mild steel, stainless steel or reinforced concrete, each with a different service life and ease of repair.
Treatment level: reuse quality needs extra filtration and disinfection, adding equipment and running cost.
Equipment origin: European, Japanese, Chinese and locally made blowers and pumps differ in price, power draw and spares supply.
Scope: standby units, PLC control, civil work, craneage, commissioning, training and a maintenance contract are in some quotes and missing from others.

Lead times and delivery

A packaged STP fabricated in Bangladesh is typically ready in 4 to 10 weeks from approved drawings; imported packaged and containerised units take longer for sea freight and customs clearance at Chattogram. A plant built on site usually takes 3 to 6 months, as concrete tanks are cast, cured and tightness tested first. Monsoon excavation and late drawings cause most delays. Roptan confirms each date in the quote.

We deliver to site across Bangladesh. The seller sets the tanks or container on the prepared base, connects pipes and power, seeds the plant with bacteria and runs it until the outlet meets the agreed standard, which takes a few weeks. Handover includes the commissioning report, lab results, as-built drawings, O&M manual, operator training and the warranty certificate, with a VAT invoice (Mushak 6.3).

What we check for this order

Trade licence and installation recordWe confirm the seller's trade licence and ask for plants that are running, with the client named, so your site is not the first trial.
Design basis and discharge standardWe get the design flow, inlet values and guaranteed outlet limits in writing, so the performance test has a fixed target.
Warranty and after sales in writingWe check what the warranty covers and when it starts, and which service visits and spares are included or priced separately.
A visit to a working installationBefore the order is placed, we arrange a visit to a running plant of similar size and process, to check noise, smell and the outlet water.

Questions buyers ask

What size of STP do I need for my building?

Start from water use. Count residents, staff and visitors, multiply by daily water use per person, and take about 80 percent of that as sewage flow. Add margins for peaks and growth. Ask the seller to show the sizing calculation in the quote.

Does a sludge-free STP really produce no sludge?

No. Every biological process grows some excess biomass. Long aeration and a long sludge age reduce it, so desludging is needed less often, but the plant still needs a sludge outlet and tanker access. Ask for the expected quantity, the removal method and whether it is part of the service contract.

Is a packaged STP cheaper than one built on site?

For small flows, usually yes, and it installs faster. For larger flows, concrete tanks built on site often cost less per m³ of capacity and last longer. Land, access and who does the civil work set the break-even, so ask for both options when your flow sits in between.

What happens to the plant during load shedding?

Short interruptions do little harm, but hours without air kill off the bacteria and the plant starts to smell. Put the blowers on the generator or backup supply, and ask for an automatic restart when power returns.

What should a complete STP quote include?

The design flow and inlet strength, the process, the guaranteed outlet limits and the tank material. It should list pumps, blowers, the control panel and standby units, and say whether civil work, installation, commissioning, the lab test, training, warranty and service visits are included. A lower total often means one line is missing.

How soon will I hear back about STP?

Within 48 hours of a complete requirement, with a price and a delivery date. A requirement is complete when it has the capacity, where it is needed and by when.

Who do I deal with?

With Roptan, when Roptan manages the order: we buy from the verified seller and deliver to you. With the supplier directly, when you post on the requirement board and choose a quote yourself.