Filtration Technology

Filtration technology helps manufacturers improve production processes, produce safer products and comply with regulatory requirements. To achieve these goals, selecting the right filtration and separation technologies is crucial.


The most basic form of filtration is gravity-based. The mixture is poured onto a filter medium and the solid particles that do not dissolve are left behind in a filter cake.

Mechanical Filtration

Mechanical filters are a common part of many water filtration solutions. These filters operate much like a sieve, catching any large waste particles that are too big to pass through the gaps in the filter medium.

These mediums are usually a mat of fibres, a bed of granules or a sponge. They are graded according to the size of their pores, with coarser filters having larger pores and finer ones having smaller pores. The medium is usually graded in terms of pores per inch (PPI), which gives a rough indication of its ability to catch waste.

Most mechanical filters operate with both surface and deep filtration. Surface filtration acts as the first few sieves in the process, removing any large debris that may have been introduced to the water through business practices. Deep filtration tackles the very small particles that are too small to be stopped by a standard mesh or sponge, using a process known as adsorption. This involves using a weak electric current to magnetize the contaminants and hold them on the filter, ensuring that even molecular-sized debris is prevented from passing through the system.

As with any filtration system, it is important to maintain regular cleaning and replacement of the mechanical filters in a sewage water treatment system. If left unclean, they will start to release waste into the water, causing a spike in ammonia or nitrate levels.

Reverse Osmosis

Reverse osmosis is one of the most important separation technologies developed in modern times. It involves the movement of solvent molecules from a lower concentration to a higher concentrated solution through a semipermeable membrane, driven by osmotic pressure, which reduces as the difference in solvent concentration on both sides of the membrane increases. Excess pressure can be applied to reverse this natural process, which is what happens in an RO system. The result is the pure water shown in the image above.

Reverse Osmosis is the technology used by premium bottled water companies and can eliminate or substantially reduce a wide range of contaminants. It can remove most inorganic chemicals including salts, metals, and minerals; most microorganisms such as cryptosporidium and giardia; and organics such as tastes, odors, colors, particulates, and bacteria. It can also remove volatile organic compounds such as benzene, MTBE, trichloroethylene, and trihalomethanes.

An RO system forces the water through a prefilter to reject sediment and chlorine; then it is forced through an RO membrane to remove the dissolved contaminants. The water is then polished with a postfilter before it is sent to the dedicated faucet. An RO system can be combined with carbon pre-filters for the removal of chloramines and other organic compounds as well as with UV treatment to further disinfect the water.

Advanced Osmosis

A reverse osmosis water filter system will produce high-quality drinking water that’s better than any bottled product you could buy. The filtered water will also make your coffee, tea and other drinks taste better. You can use the filtered water for cooking, rinsing dishes and more.

A high rejection membrane allows water molecules to pass through while blocking dissolved minerals, bacteria and other suspended contaminants. The process creates clean, healthy and refreshingly crisp tasting water. It reduces the levels of dissolved solids and mineral content in water as well as removing bacteria, viruses and cysts.

Reverse osmosis uses pressure to reverse the normal osmotic flow of water through a semi-permeable membrane. In normal osmosis, water flows from an area of lower concentration through a membrane to an area of higher concentration to reach equilibrium (an equal volume of solvent on each side of the membrane).

This process is used by the world’s ocean desalination plants to extract fresh water. Reverse Osmosis technology has the potential to bring fresh water to millions of people in a sustainable way and could help solve global water shortages, particularly in developing countries.

Graphene oxide and carbon nanotubes are being investigated as materials for membranes for their tunable pore structure, mechanical stability, chemical tolerance, salt rejection, and water permeability. These new membranes, along with other cutting-edge technologies, can create advanced, inexpensive water purification systems that may allow for a sustainable supply of drinking water at an atomic level in the world’s oceans.

Chemical Compatibility

Chemical filtration technologies separate liquid solutions from solid contaminants to create more valuable products, minimize waste and comply with environmental regulations. They also can improve food production processes, produce safer products and help businesses minimize costs.

Filtration differs from sieving, where separation happens at a single perforated layer (sieve). In filtration, the particles are retained in a multilayer lattice of membranes that can be customized to fit a wide variety of specific applications. In chemical processing, a filter can separate liquid from solids, concentrate or clarify a solution, and even recover electricity and light.

In oil and gas processing, the compatibility of chemicals with the materials used in fracturing, completion, storage and hydrotest fluids is critical to prevent equipment failures caused by corrosion, solids formation, evolution of gases or other unwanted reactions. These incompatibilities can lead to plugged injection lines, leaks and reduced system efficiency.

This chemical resistance chart can be used to determine which materials are compatible with various process chemicals, preventing chemical corrosion or other damage that could cause leaks and other safety hazards. This chart does not represent a complete list of compatible chemicals and is for general reference only. When selecting a material for use with a specific chemical, it is important to consult the safety data sheet for proper handling and storage procedures.