Ultrafiltration is an improved filtration process used in drinking water, and tertiary wastewater reuse applications. It is a pressure-driven membrane separation technology. Its semipermeable membrane can eliminate particles as small as 0.01 microns, such as silt and viruses.
But on the other hand, UF can have issues if due care is not taken for optimum pretreatment, operation, and maintenance.
What are the most common problems of UF Systems?
The major conce?rns which commonly influence UF systems include,
· Waste stream disposal
This is concerning to the UF concentrate discharge.
The filtering system completes its job, and you now have clean water that you may safely release into an outdoor stream, without fear of incurring environmental regulation fines. Or, maybe you'll repurpose it in some way. You have this water supply regardless of what happens to it.
This rejected wastewater contains a concentrated version of whatever was in the feed water. As a result, while it may be permissible to dump it into the environment in some situations, the facility may face substantial penalties if it contains dangerous pollutants.
· Membrane pollution
Membrane fouling can occur with UF systems, like with any other membrane separation process, including reverse osmosis. In other terms, fouling occurs when particulate matter attaches to the surface of a membrane. Unchecked accumulation will eventually result in a decreased efficiency, pressure drop, and greater energy usage.
Fouling can occur in many ways. Each has its own cause and some differences, in effects. Some of these membrane foulants are reversible, while others are irreversible.
· Membrane Scaling
Membrane scaling is similar to what happens in pipes carrying water, containing high quantities of hardness compounds. When the concentration of these dissolved minerals, reaches the saturation limit of the solvent solution, they begin to precipitate out of the solution onto the membrane's surface.
These minerals can crystallize, making removal practically impossible without some kind of chemical cleaning, or antiscalant pretreatment. Calcium and magnesium are the two of the most common minerals, which can produce scaling on the membranes of Ultrafiltration systems.
Suspended solids and colloidal particles accumulate on the surface, and within the pores of the ultrafiltration membrane, preventing water from passing through. This fouling is more common in applications with high turbidity and suspended particles, which do not receive adequate pretreatment.
· Microbiological contamination
Common biological pollutants, like algae and bacteria, are found in surface water sources. When exposed to a warm climate and low flow rates, these pollutants will cling to the surface of a membrane and multiply. They can build a film over time, preventing water from moving through the membrane, and increasing the transmembrane pressure differential.
This higher-pressure differential will put more strain on the pumps, and increase their energy consumption.
· Increased permeate contamination
This is a somewhat uncommon occurrence in well-maintained and monitored systems. To recap, permeate is water that has been separated from polluting solids. The result of this filtration procedure is pure water. As a result, if you see that the quality of your permeate water is deteriorating, you have a problem. Larger materials or germs that should have been contained by the membrane have contaminated the water.
This reduction in removal effectiveness is usually suggestive of a faulty membrane. Polymeric membranes can degrade over time. High temperatures or pH levels can quickly deteriorate them, and abrasive particles can damage the inside pores of the membrane, if not properly pre-treated.
To emphasize the obvious, membranes do not function well, if they are riddled with extra holes, and, now the system is failing to satisfy its design criteria, necessitating the replacement of the membrane, and the recirculation of polluted permeate.
Ultrafiltration (UF) is a membrane-based filtering technology that separates contaminating particles, such as organic material, germs, suspended solids, and other pollutants, using thin layers of semi-permeable membrane. With the continuous working and lack of maintenance,UF can have several problems which need to be solved timely.
How can we assist?
Netsol Water offers the best Commercial and Industrial RO Plants, to fulfil the needs of our clients all over the world. We are always there to help everyone, by solving water problems in every area. We offer the most reliable technologies including membrane filtrations, like Ultrafiltration, which have several advantages and applications.