To Filter or Not to Filter

Posted by on Sunday, December 20, 2015

Very often, the first thing people think about when they have something in their water is, “I need a filter.” The next thing people think about is the downside of using a filter. Filters get dirty, create pressure loss, and often need to be taken apart and cleaned. As quickly as someone thinks they need a filter, they just as quickly talk themselves out of it.

It is important to understand that the LAKOS Sand Separator is and is not a filter. The LAKOS separator is a particle separator and, by definition, not a filter. There is a need for all types of products in filtration, from particle removal to water treatment. The LAKOS separator is most typically a prefilter, installed after a pump and before finer filters or water treatment. The LAKOS system removes larger particles so that finer filtration systems can take over after the removal of those heavier sediments or solids—the ones that would settle out in three to four minutes in still water or fluid. With larger particles removed, finer filters and water treatment can do their job better with less maintenance and servicing and fewer replacements.

A separator’s role as a first-stage filter is critical. For example, a number of traditional filtration devices are meant to change the taste, color, and odor of water or fluid by using extremely fine membranes, screens,and treatment media; the problem is that they are very vulnerable to the bulk of the sand, sediment, grit, and precipitated minerals—all the different types of harmful particles that can clog and abrade the various components of the system. Fine filtration systems are typically not designed to filter larger particles.

The problem can be resolved by recognizing that it is more efficient to use two or more filters when faced with two or more types of contaminants in the water. After the LAKOS separator does its job, the finer traditional filters can efficiently remove the finer particles. Users often do not realize that common 2- to 5-micron filters will need to be cleaned or replaced far more often if relied on to remove heavier, larger particles. Debris will accumulate quickly and shut a fine filter system down. The LAKOS system addresses all these concerns. It does not create the same loss in pressure and does not need to be cleaned as a standard filter. The product purges just the dirt and very little water and, therefore, wastes little water. Many other types of filters use a large amount of water to backwash or flush the debris from filter screens. Using the LAKOS separator as a prefilter allows the finer filtration systems to run longer and more efficiently. LAKOS helps to eliminate the larger particle problem instead of just moving it around.


LAKOS Sand Separators remove sand and other solids from pumped water and other fluids. There are no screens, cartridges, or filter elements. The key to removing solids is centrifugal action.

As water enters the sand separator, it immediately transfers from the outer chamber to the inner chamber through tangential slots. Those slots maintain the centrifugal action in the same direction and accelerate the water into a smaller diameter chamber. That allows centrifugal action to do what gravity would do over time. So, the performance of a separator is predicated on the weight of a particle, and not on its size.

A rule of thumb is that if the particle matter or sediment would settle within three to four minutes in still water, then those particles are separable in a LAKOS separator. Once those particles get pushed to the outside, they will gradually fall down the perimeter, past the deflector plate, and into the collection chamber. While the centrifugal action creates an outward pressure, there is also a low pressure at the center. Water follows the lowest pressure, the vortex of that tornado, and migrates upward to the center of the separator to a smaller diameter pipe—the vortex outlet. So all the water goes in, dirt is spun to the bottom, clean water spirals up the operative separator, and the particles fall to the collection chamber, where they are either periodically or continually purged from the separator to evacuate the unit.

History of the Separator

Claude Laval Jr. invented the original technology, a device called a borehole camera, which would go down into water wells and inspect for damage in order for wells to be repaired and rehabilitated. Laval’s borehole camera showed the industry that there was a lot of sand infiltration in water wells and that a product design that removed sand to protect the pumps from premature wear would be innovative. The first device to use such technology was the downhole sand separator, which protected turbine pumps in the big agricultural regions of central California. Irrigators were skeptical at first. Laval responded by inventing an above-ground version of the downhole separator to prove the theory. Suddenly, applications emerged across a wide range of activities and markets all over the world.

LAKOS Systems Have Many Applications

Since the sand separator’s introduction in central California, LAKOS has moved the separator beyond agriculture and irrigation into processing applications. Today, separators are used in municipal water systems, power plants, steel mills, oil and gas operations, HVAC, cooling tower filtration, and mining.

LAKOS systems bring filtration improvements to many activities for many entities, including individuals who use residential water well systems; landscaping businesses that need to protect sprinklers from the abrasion of sand and grit; municipal water providers that recycle water; and factories that aim to keep water losses to a minimum.

The drought in the West has increased demand for the sand separator. As irrigators adopt more efficient irrigation systems, the nozzles and orifices used to broadcast the water are becoming finer and requiring filtration sufficient to keep the flow from clogging.

Cities often come to LAKOS seeking to change their filtration systems because the current ones are so maintenance intensive. They are astonished at the improvement our systems can make. Cities can be very cautious and very conservative, but our approach to reliability can give them confidence. For example, the City of Phoenix, Arizona, equipped most of its water wells with sand separators, extending the life of water meters and reducing operating costs associated with meter repair and replacement.

Life Cycle Costs Are Competitive With Other Technologies

In comparison to LAKOS, traditional filters will be less expensive on the front end. It is important to keep in mind, however, that the cost of a separator is not just in the purchase of the unit, but in the manpower and replacements that accompany the system. The long-term costs of a LAKOS system are comparable to a traditional filtration system.

The price of the product drops with every consideration of a traditional filter. You do not have to pay to have someone clean the system or to replace the parts, and there is no worry about water loss. Most filters have ongoing replacement cycles that shut down overall services and use a large volume of water to flush the filter components, leading to water loss, increased wastewater fees, and increased energy costs.

In terms of service life, separators have roughly the same life cycle as the pipes used in a water transmission system. The sand separator does not succumb to abrasive wear as it does to corrosive wear. It is the nature of the fluid that dictates the life of the product, not the particles. There are LAKOS units that were installed 50 years ago that are still in service today. In one case, a steel mill took a 25-year-old separator system offline because it thought the service life had ended. When the system was opened up, we discovered it was in great working order and looked like a new unit.

A LAKOS separator, acting as a prefilter, can significantly change and enhance the entire filtration process for municipal water suppliers and irrigators. Our company’s approach is not just about removing particles from the water, but also removing them from the product and from the facility. I have been representing LAKOS products for 38 years. Every year, I meet people who have never heard of the sand separator. It is exciting to introduce this product to people for the first time because they are often surprised that filtration technology has become so advanced. The LAKOS system will allow many entities to adapt to a wide range of water-related challenges in the 21st century. Our goal is to continue advancing the technology to help them more effectively and efficiently meet those challenges every step of the way.

By Randy Delenikos, Vice President of Waterworks at LAKOS
Article featured in the Municipal Water Leader - October 2015 magazine

* Required