Package plants and membranes
Package MBR plants combine screening, aeration, membrane tank and controls in steel or concrete tanks delivered as units. The membrane is usually the part with the shortest life, so owners should plan for replacement from the start, and ideally have more than one source.
Upgrading older plants
Extended-aeration package plants with clarifiers can sometimes be converted to MBR to increase capacity or meet tighter limits. See increasing capacity.
What we supply
Zyramic supplies membrane modules to package-plant builders, replacement flat-sheet membranes to plants already in service, and rentals for US plants that need interim capacity. For funded projects, tell us your domestic-content requirements and we'll review what we can document.
| Mild backwash (special cases only) |
|---|
| Backwashing is not a standard Swing operating mode and is not meant for routine use. Swing has been pressure-tested to 14.5 psi (1 bar) and held without breaking. If a site is in a bind even after relaxation and CIP, contact us; we may be able to work out a special mild-backwash procedure. |
Worked sizing example
Take a village package plant at 66,043 gpd (250 m³/day):
| Item | US | Metric | Note |
|---|---|---|---|
| Average flow | 66,043 gpd | 250 m³/day | about 46 gpm (10,417 L/h) |
| Design flux (gross) | 11.8 gfd | 20 LMH | Zyramic design guidance |
| Derate for relaxation and cleaning | ~20% | ~20% | |
| Net flux | ~9.4 gfd | ~16 LMH | |
| Membrane area needed | ~7,008 ft² | ~651 m² | average flow ÷ net flux |
| Swing-8 cartridges | ~53 | ~53 | 135 ft² (12.5 m²) each |
| Peak factor | ~3.0 | ~3.0 | |
| Peak flow | ~198,129 gpd | ~750 m³/day | extra area, short-term higher flux, or equalization |
This is an illustration only; a real design also checks temperature, MLSS, redundancy and the cleaning schedule.
Tips for a smooth project
- Plan for peaks from batch and cleaning discharges
- Size equalization and pH control generously
- Keep fats, lint and solids upstream of the membrane tank
- Use pilot data to choose design flux
Next step
Industrial and special-purpose plants vary widely, so every first conversation starts with fact-finding. A few weeks of flow and lab data, even rough, makes our recommendation far more reliable. Where questions remain, a pilot or a measured first phase is a good way forward.
Sizing considerations
To give a useful recommendation we usually need:
- Plant make, size and age
- Current membrane type
- Permit limits
- Funding source
- Growth projections
Most relevant product: Swing MBR. See also replacement membranes, rentals and how to choose.
Why engineers look at Zyramic flat-sheet modules
| Item | Details |
|---|---|
| Smaller sheets, less wear and tear | each sheet flexes less in service, and a damaged unit affects less area. |
| Strong wide membrane welds | designed to resist delamination over the membrane's life. |
| Thick, robust membrane | about 250 microns including support. |
| Assembled in Poughkeepsie, NY | of domestic and imported components. In our Poughkeepsie shop we cut and weld membrane sheets to plates, build module frames and assemble complete modules. For funded projects, tell us your domestic-content requirements and we'll review what we can document. |
| Buy, rent or replace | new modules, rentals and pilots for US projects, and replacement membranes that fit many existing cassettes. |
Performance and life depend on pretreatment, design flux and operation; flux figures are Zyramic design guidance, sized to each project.
Frequently asked questions
Can you replace membranes in a package plant from another builder?
Often, if they are flat sheet. Send dimensions and photos.
Can you meet domestic-content requirements?
Tell us your requirements and we'll review what we can document.
Do you sell complete package plants?
No; we supply membranes to builders.
Can we rent during a rebuild?
Yes, for US plants.
How long do package plant membranes last?
It varies with operation; plan replacement on a multi-year cycle and track permeability.
Can we add capacity to our package plant?
Sometimes, by adding membrane area or tanks; send drawings.