How to Size a Containerized MBR STP for Tehran Residential & Camp Projects (2026 Guide)

What a Containerized MBR STP Actually Is

A containerized membrane bioreactor (MBR) sewage treatment plant is an activated-sludge biological stage coupled with submerged PVDF hollow-fiber ultrafiltration at a nominal pore size of 0.04 µm, with the bioreactor, membrane tank, blowers, dosing panel and PLC all pre-assembled inside a 20' or 40' ISO high-cube (HC) container. Pure Aqua's MBR-C datasheet lists the standard packaged contents: a 1.5 mm drum screen for hair and debris removal, an aeration tank fed by fine-bubble diffusers, a membrane tank with coarse-bubble air scouring, a built-in chemical cleaning loop, standby feed pumps, an anoxic zone for denitrification, and a PLC with remote monitoring.

The operating envelope is the second thing an engineer has to internalize. Pure Aqua rates the MBR-C for an ambient range of 20–30°C with a design temperature of 20°C. That covers Tehran's summer conditions but is at the edge of what an MBR will tolerate in winter, when sewage temperatures regularly fall below 15°C. HINADA's published delivery range is 10 m³/d to 500 m³/d, so the same containerized architecture covers both a small apartment block and a multi-hundred-person worker camp, the relevant equipment being a containerized MBR wastewater treatment system with a MBR flat sheet membrane module suited to the chosen flow band.

The Six Inputs You Need Before Sizing

Quotations collapse when one of these six inputs is guessed at the inquiry stage. Lock them down before asking any supplier for a model number.

• Population (P). Count residents for a Tehran apartment block, or beds × shift factor for a remote camp. Pure Aqua's reference table is built on 50 US gpd per capita, which converts to roughly 190 Lpcd per the IDA Water Security Handbook unit table (1 m³ = 264.2 US gallons).
• Average dry-weather flow, Qavg. Qavg = P × unit flow. At 0.19 m³/d per person, 500 people give 95 m³/d and 300 people give 57 m³/d.
• Peaking factor (PF) and Qpeak. Use 2.0–2.5 for residential Tehran blocks and 2.5–3.0 for camps with shift-change showers. Qpeak = PF × Qavg governs hydraulic capacity, while Qavg governs biological sizing.
• Organic load. Pure Aqua's MBR-C design basis is BOD 250 mg/L, COD 400 mg/L, TSS 200 mg/L for municipal sewage. Camps with food service or worker kitchens should request a higher BOD from the supplier rather than assuming 250 mg/L.
• Ammonia load. NH₄-N 30 mg/L feed and <2 mg/L permeate, per Pure Aqua's reference table. Nitrification needs a defined HRT at the design temperature, so request the supplier's design MLSS and SRT before sizing the aeration volume.
• Discharge target. Confirm in writing whether the Tehran project must meet Iran Department of Environment effluent limits for discharge to surface water, irrigation reuse, or sewer — each case changes the post-MBR polishing required.

Step-by-Step Sizing Method for a Tehran Project

The method below is the calculation chain a Tehran consulting engineer can put in front of a client or a regulator. It uses two worked cases — a 500-person Tehran apartment block and a 300-person Alborz-region worker camp — and a reference to Pure Aqua's MBR-C sizing table.

Step 1 — Population. 500 residents for the apartment block; 300 workers for the remote camp. Confirm whether the residential count is design occupancy or registered units, and whether the camp count applies per shift or per day.

Step 2 — Qavg. At 0.19 m³/d per capita (50 US gpd, Pure Aqua), 500 people give Qavg = 95 m³/d and 300 people give Qavg = 57 m³/d.

Step 3 — Peaking factor and Qpeak. Use PF = 2.0 for the Tehran block (steady residential diurnal pattern), giving Qpeak ≈ 190 m³/d. Use PF = 2.5 for the camp (shift-change shower peaks), giving Qpeak ≈ 143 m³/d. Qpeak governs hydraulic capacity, Qavg governs biological capacity.

Step 4 — Biological volume. Size the aeration tank for BOD 250 mg/L, COD 400 mg/L, TSS 200 mg/L feed (Pure Aqua MBR-C design basis) and the supplier's stated MLSS and SRT. Pure Aqua's MBR-C architecture puts the aeration tank inside the container, so this drives whether one 40' HC is enough or two are needed in parallel.

Step 5 — Membrane area and modules. Pure Aqua's reference table ties 50 m³/d to 2 skids × 3 modules in a single 20' HC, 100 m³/d to 2 skids × 5 modules in a single 40' HC, 150 m³/d to 2 skids × 8 modules in a single 40' HC, and 190 m³/d to 2 skids × 10 modules in a single 40' HC. The Tehran block at Qavg = 95 m³/d falls on the 100 m³/d row; the camp at Qavg = 57 m³/d falls between the 50 m³/d and 100 m³/d rows. Select the container envelope on Qpeak, not Qavg.

Step 6 — Sludge and residuals. Design the waste-sludge withdrawal rate around the supplier's stated SRT. Pure Aqua's MBR-C literature notes lower sludge production than conventional activated sludge, but the containerized MBR still needs a downstream plan for sludge storage and dewatering, typically a small plate-and-frame filter press sized to the wasted solids.

Selecting the Container: 20' HC vs 40' HC, Skids, Modules

The Pure Aqua MBR-C reference table is the key to converting Qavg and Qpeak into a specific container order. Re-stating it for direct read-across:

For the 500-person Tehran apartment block, Qavg = 95 m³/d sits on the 100 m³/d row and Qpeak = 190 m³/d sits exactly on the 190 m³/d row. A single 40' HC unit on the 190 m³/d row (2 skids × 10 modules) handles the peak; the 100 m³/d row will not absorb Qpeak without a TMP excursion, so size the container on Qpeak and verify with the supplier that the MBR-C architecture can accept 190 m³/d sustained.

For the 300-person camp, Qavg = 57 m³/d and Qpeak = 143 m³/d. The 50 m³/d row (1 × 20' HC, 2 × 3 modules) handles Qavg but not Qpeak, so step up to the 150 m³/d row (1 × 40' HC, 2 × 8 modules). Above 190 m³/d, HINADA's published 500 m³/d upper bound means paralleling multiple 40' HC containers, not specifying a non-standard single unit.

One item Pure Aqua's datasheet flags explicitly and that the SERP competitors ignore: electrical supply. The MBR-C standard is 460 V / 3-phase / 60 Hz. Tehran's distribution standard is 400 V / 3-phase / 50 Hz. Request a transformer or a regionally rated panel from the supplier before order, otherwise the blowers, pumps and PLC will not run on site power.

Tehran-Specific Adjustments to the Design

Generic MBR sizing breaks down in Tehran if these four adjustments are skipped.

Temperature. Pure Aqua rates the MBR-C for 20–30°C with a 20°C design point. Tehran winter sewage temperatures fall below 15°C, which slows nitrification kinetics and can force a winter derating on MLSS and HRT. Ask the supplier for a stated winter capacity and whether the aeration tank can hold the resulting larger volume inside the same container envelope.

Reuse. Where the client wants treated water for landscape irrigation inside the residential compound, the MBR permeate (BOD <10, TSS <5 mg/L per Pure Aqua) is typically adequate for restricted irrigation, but a polishing step is still required for any contact-reuse or cooling-tower application. A chlorine dioxide disinfection generator or a UV polish is the usual add-on.

Site constraints. Pure Aqua's MBR-C list includes "quick installation" and "easy to relocate" as standard features, which suits infill Tehran sites where civil work is expensive and where future relocation is a possibility. A worker camp is the second obvious fit.

Logistics. 20' and 40' HC ISO footprints are road-legal into most Tehran districts, but confirm axle loads for the heaviest 40' HC unit on the project's access road, and check the lifting plan for any basement or rooftop installation.

What to Confirm With the Supplier Before You Order

Five items convert the engineering work above into a comparable quotation.

• Flow reference basis. Ask whether the supplier's model is sized on Qavg or Qpeak, and against which per-capita figure. Pure Aqua uses 50 US gpd, but Iranian EPCs often work in 150–200 Lpcd, which can shift the model row selected.
• Feed design basis. Request the influent BOD, COD, TSS and NH₄-N used to size the aeration tank. Pure Aqua's reference is BOD 250, COD 400, TSS 200, NH₄-N 30 mg/L; for Tehran camps with food service, request a feed BOD higher than 250 mg/L and re-run the biological sizing.
• Effluent guarantee vs typical. Pure Aqua's MBR-C datasheet explicitly marks the permeate values as "not guarantees". Ask the supplier for a written effluent performance guarantee tied to the actual Tehran discharge standard and the project's reuse case.
• Electrical standard. Confirm 400 V / 3 ph / 50 Hz compatibility, since the Pure Aqua standard is 460 V / 3 ph / 60 Hz. A transformer or a re-rated panel is not optional.
• Remote monitoring. Pure Aqua lists remote monitoring as standard. Confirm what data is exposed (TMP, MLSS, flow, DO, pH) and whether the SCADA tag list is open or proprietary, because that affects what your local controls integrator can connect to.

Frequently Asked Questions

What per-capita flow should I use to size a containerized MBR for a Tehran apartment block?

Use the figure your supplier has used to size the unit, then translate to a defensible Iranian value. Pure Aqua's MBR-C reference table is built on 50 US gpd per capita, which is 0.19 m³/d per person using the IDA Water Security Handbook conversion of 1 m³ = 264.2 US gallons. If your local EPC brief specifies 150–200 Lpcd, request a re-sized quote rather than assuming the 50 gpd basis still applies.

How do I select between a 20' HC and a 40' HC for a 300-person camp?

Size the container on Qpeak, not Qavg. For a 300-person camp at 0.19 m³/d per person, Qavg = 57 m³/d and Qpeak at PF = 2.5 is about 143 m³/d. The 50 m³/d row in a single 20' HC (2 skids × 3 modules) handles Qavg but not Qpeak; step up to the 150 m³/d row in a single 40' HC (2 skids × 8 modules). For projects above 190 m³/d, parallel multiple 40' HC units, since HINADA's published ceiling is 500 m³/d and that is reached by paralleling standard containers, not by oversizing one.

What does a containerized MBR cost for a Tehran residential or camp project?

No usable price band is given in the supplied research; Pure Aqua's MBR-C datasheet lists flow, skids, modules and container size but not a unit price, and HINADA's product page references "competitive factory pricing" without a figure. The right input to request from any shortlisted supplier is a written quote tied to your Qavg and Qpeak, the feed BOD/COD/TSS/NH₄-N you will operate to, the permeate targets you must hit, and a confirmed 400 V / 3 ph / 50 Hz electrical configuration. Do not compare vendors on a bare model number — compare them on those four inputs plus a written effluent guarantee.

How do I shortlist containerized MBR suppliers for an Iran project?

Shortlist on four checks that the supplied research makes testable. First, can the supplier quote against the Pure Aqua MBR-C reference row (50, 100, 150, 190 m³/d) so the comparison is read-across? Second, can they provide a written effluent performance guarantee against the actual Tehran or Iran Department of Environment discharge standard, not just the "typical" permeate values on a datasheet? Third, can they deliver a 400 V / 3 ph / 50 Hz panel without a separate transformer skid? Fourth, do they publish the remote-monitoring tag list (TMP, MLSS, flow, DO, pH) so your local controls integrator can pull data into the site SCADA? Suppliers who answer all four in writing are the defensible shortlist. For a country comparison of BOD and TSS discharge limits that you can use to set the permeate target, see this country comparison of BOD and TSS discharge limits, and for a parallel sizing walkthrough using a Surat case see containerized MBR sizing for Surat residential and camp projects.

Further Reading

• containerized MBR sizing for Bandung projects