Tubular UF Membrane Technology
Process Explanation
🧪 Membrane-Based Separation
Wastewater recirculates within membrane tubes; the membrane’s porosity (MWCO) determines what passes through.
💨 Enhanced Diffusion via Backpressure
Applying slight backpressure accelerates permeate diffusion across the membrane.
🌀 Shear Forces Minimize Fouling
High-speed recirculation creates shear forces that prevent deposits on the membrane surface.
🚫 Resistance to Blockage
Large-diameter tubes are less prone to clogging from suspended solids in the feedwater. Pre-treatment needs are minimal.
🧼 Lower Maintenance Requirements
Reduced fouling means less frequent cleaning compared to hollow-fiber ultrafiltration systems.
System Design Tips
🚀 Smart Design Over Sheer Scale
Simply increasing membrane count in larger housings doesn’t guarantee better output—efficient flow dynamics matter more.
🔄 Flow-Friendly Engineering
Long module lengths and smooth pipe transitions minimize friction losses and pump strain, keeping flow rates optimal.
⚡ Balanced Performance with Modest Pumps
Chaining modules in series boosts surface area while keeping diameters low, enabling affordable pumps to be used.
🧠 Efficiency Through Thoughtful Choices
Low-resistance fittings and strategic layout ensure the system is maintainable, and runs smoothly without excessive energy demands.
Required components & cleaning
⬆️ Non Return Valve (NRV)
Prevents siphoning and ensures the Module(s) stays in an immersed state when the drive pump is switched off. Can also be placed closer to the drive pump.
🗑️ Strainer
Removes large particles from blocking the membrane tubes. Follow the module guidance notes for selecting the optimum mesh size. Adjust feed tank suction depth to further reduce risk of strainer blockage.
🦋 Butterfly valve
Applies a slight backpressure on the feed line, enhancing diffusion across the membrane interface. Also used to seal off the system when not in use.
💪 Pump spec
Purus’ DN50 UF Modules can be used with solids-capable high-flowrate submersible pumps such as the DAB Feka VS 1200 in a single module config, or the Speroni PRM 300 N-V for a series of 3 and more modules. Yield depends on suspended solids concentration and total dynamic head. Contact us for guidance on a pump adapted to your needs. A variable frequency drive (VFD) can ensure the pump operates at the optimum flowrate without incurring excessive friction losses. The VFD can also be used to temporarily increase velocity within the system, enhancing membrane scouring, resulting in an anti-fouling effect.
🧹 Module conditioning
Each module is shipped with details on the start-up procedure and cleaning methods. Regular in-process cleaning is generally via permeate. For pre-shutdown cleans and storage, use a basic (pH 10) solution. Periodic acidic cleaning (pH 4) may be necessary if the feed water is very hard. Deep clean involves a mixture of dilute Sodium Hypochlorite (0.2 ‰) solution and non-ionic surfactant (0.25%).
Tubular UF Membrane Solutions
Typical system configuration
🩸 Feed
A submersible pump immersed in the wastewater tank circulates the feed through the Tubular Ultrafiltration Modules in a loop designated the feed line.
⚗️ Permeate
The permeate produced by the module(s) is collected in a separate and intermediate tank. Within this tank, a smaller submersible pump is placed, connected to the input of the module under protection of a check valve in order to facilitate periodic cleaning. A dosing pump can be connected to this line to raise/lower the pH depending on the conditioning needed. The permeate tank can be fitted with an immersed UV lamp (from Purion) to disinfect the water before delivery.
🎛️ Purified water use
A boost/pressure pump connected to the drain of the permeate tank can be used to fulfill the needs of a plumbing system supporting toilet flushing, irrigation or process needs. If further treatement to remove PFAS is needed, the pump can be connected to a RO membrane module.
🤖 Automation
Simple automation is achieved by controlling the pump switching with inbuilt float sensors, and sensing for blockages with the help of a programmable inline energy meter switch like a Shelly Pro 4PM. Blockages and dry running manifest as reductions in the energy draw of the pump, so by employing ITTT programming along with webhooks, one can shut down the pumps when threshold limits are crossed, and send appropriate notifications to the user. Ensure your system is grounded and employs safety devices like RCCBs, and MCBs for human and device protection. Your design and installation must be performed by a qualified electrician.
If instead a high-quality ready to go solution is required, consider one of our controllers, or contact us for a customised control panel.
Example Use Cases
🚿 Greywater Reuse Made Simple
Ideal for direct filtration of greywater (REUT of EICH type), offering high-quality purification with minimal pre-treatment and excellent uptime for attaining A+ quality water.
🥅 Microplastic elimination
For industrial processes like injection molding where manufactured parts are cooled by water, and contaminate the same, direct filtration via tubular UF membranes concentrates fine plastic suspensions, reducing waste volumes.
☣️ PFAS pre-filtration
Reverse Osmosis (RO) is the proven method for reducing PFAS in wastewater, and Ultrafiltration is the recommended pre-filtration stage. Tubular UF technology can extend the lifetime of expensive RO membranes, by delivering a feed free from suspended solids, while also being tolerant of influent quality variations, resulting in minimal process downtime and yield loss due to cleaning cycles.
🔋 Boosting Biogas Production
Perfect for external anaerobic membrane bioreactors (AnMBRs), thanks to its accessibility, suspended solids tolerance and reduced fouling compared to submerged systems.
🌱 Fertiliser generating Aerobic Treatment
Also effective in aerobic membrane bioreactors (MBRs), producing nutrient-rich sludge suitable for agricultural use.
🏗️ Construction Site and Quarry Wastewater Management
Well-suited for treating wastewater with heavy clay and sediment loads, making it a robust solution for on-site construction works discharge compliance. For similar reasons, it is useful in quarry water conformity, especially in quaternary treatment mode.
Purus offers filtration modules, low-cost systems, and a mobile platform to suit diverse operational needs.
💎 Balanced Performance Advantages
Our technology delivers high-quality purification, handles a wide range of inputs, and requires minimal pre-treatment.
🧼 Low Maintenance, High Reliability
With reduced fouling and fewer cleaning cycles, our systems ensure consistent uptime and dependable performance.
🚀 Accessible Innovation for All
We lower the barriers for businesses to pilot advanced filtration—no need for complex infrastructure or high upfront costs.
📈 Regulation-Ready and Competitive
By enabling compliance with emerging water regulations, Purus helps organizations stay ahead and build a strong sustainability case.