Lakos – Sand Filter
Stainless steel, epoxy lined carbon steel and fiberglass-reinforced polyester sand filters for cooling towers
Sand Media Tanks engineered for the demands of applications on cooling towers, as well as open and closed loop system operations, down to 5-10 micron performance range as standard.
Flow Range: 18 – 310 US GPM (higher single tank flow rates are available)
Accessories: Backwash throttling valves & pressure gauge kits
Filtration Principal of Operation
A system-matched pump directs the fluid through a 3-way valve into the top inlet of the sand media filter tank. Flow is evenly dispersed across the sand media bed via a dispersion plate, allowing the fluid to pass through the sand media and capturing the contaminants on the surface and upper layer of the sand media. Fluid flow continues through the sand media to the filter tank’s integral underdrain, directing water to the filter system’s outlet.
The underdrain features a full-size manifold with complete coverage laterals to ensure that filter flow and backwash flow are uniform across and throughout the sand media bed.
The accumulation of contaminants on the sand media surface is be monitored via pressure differential from inlet to outlet. At a prescribed pressure differential or a given period of time or operator discretion, the filter system will backwash the captured contaminants to desired waste. This function will be a) automatically controlled via a pressure differential gauge and clock timer, or b) manual, monitored and initiated by an operator.
The 3-way valve at the inlet is actuated hydraulically by solenoid or manual valve to interrupt system flow and provide a backwash discharge outlet. Backwash flow comes from either a) the system flow, redirected through filter tank’s outlet and underdrain, or b) a separate flow source, such as city water, directed through the filter tank’s outlet and underdrain.
Backwash flow and pressure shall be sufficient to fluidize the sand media bed and cause the surface contaminants to rise in suspension and discharge via the 3-way valve to desired waste.
Upon completion of the backwashing cycle, the inlet’s 3-way valve will again return to its operating position, allowing system flow to enter the filter tank and simultaneously interrupting backwash discharge. This allows the sand media bed to again settle, forming the filtration surface for further contaminant removal.