MEMBRANE TECHNOLOGY
Membrane technology has been key in achieving efficient separations across a multitude of industries from water and wastewater treatment to pharmaceutical manufacturing and even food production. While membrane technology has been around for decades, advances over the past 20 years have seen the technology rapidly expand and gain traction across a variety of sectors.
Membrane technology, in its most basic form, involves the use of a thin barrier with varying degrees of selective permeability, allowing one or more components of a solution to pass through while restricting, or completely blocking, other components. The separation of desired compounds can be achieved through a variety of mechanisms depending on the type of membrane used, including size exclusion, charge repulsion, and adsorption.
One of the key advantages of membrane technology is the low energy requirements when compared to traditional forms of separation such as distillation or evaporation. Membrane technology also provides improved separation efficiencies and limits the use of harmful chemicals and sources of contamination. This leads to a substantially reduced impact on the environment and increased safety in certain industries such as food processing.
The most common type of membrane used in industrial applications is the reverse osmosis (RO) membrane. RO membranes are used for marine desalination to create fresh water from saltwater, as well as for water and wastewater treatment to reduce the concentration of soluble salts and other impurities. The main principle of the RO process is to reduce the solute load on the membrane by generating a hydrostatic pressure gradient across the membrane surface. This gradient is created by introducing a pressurized feed solution on one end of the membrane and then allowing the solution to flow across the RO layer before being released at the other side. As the feed solution permeates through the membrane, the limited permeable solutes are transferred, while the other solutes cannot pass through the membrane and are either discarded or recovered on the reject side.
The food industry has also benefited from the use of membrane separation technology as it allows for the processing of raw materials and the production of high-quality products with fewer contaminants and with a shorter processing time. Some of the most common applications of this technology include the separation of milk into cream and skimmed milk, the concentration of fruit juices, the clarification of beverages, and the fractionation of proteins and carbohydrates.
Membrane technology may also be used in biopharmaceutical manufacturing. The use of membrane technology can help to achieve particle size or species selectivity, further purify or concentrate process streams, and help to separate aqueous or non-aqueous phases. The high-flux membranes also help to reduce fouling and clean times, resulting in better process control and higher product yields.
In addition to its various industrial applications, membrane technology is becoming increasingly popular in both healthcare and consumer markets. Recent advances in the technology have seen membrane dialysis units become a commonplace home therapy for people with kidney disease, while the development of artificial ‘breathable’ membranes has allowed for the production of medical-grade fabrics for use in garments for a variety of medical purposes.
Membrane technology has come a long way over the past few decades and continues to prove its worth in a variety of industrial, healthcare and consumer markets. With continued innovation in the field, it is likely that membrane technology will only continue to expand and improve as time goes on.
