More and more HVAC professionals recognize the responsibility of implementing water saving solutions.One of the simplest ways to conserve water in an HVAC water-cooled system is to utilize a solids separator for filtration in-lieu of conventional sand filters.
The evidence for water savings is in the component's principles of operation. Let's take a closer look:
Sand Filters
Sand Filters direct the fluid into the top of their tank and onto a bed of specified sand. As the fluid makes it's way through the bed of sand media, the contaminants become captured at the top of the media. The fluid makes it's way downward through the bottom of the tank and is discharged at at outlet pipe or manifold.
In order to remove the captured contaminants, flow is reversed. This fluidizes the sand media and backwashes the contaminants through the tank's inlet into a disposal discharge line.The problem is that water is also dumped down the drain in order to remove the contaminants from the system.This backwash occurs for a minimum of 3 minutes a day plus any time the pressure differential in the tank becomes too high.
Solid Separators
Solid Separators utilize centrifugal action to remove particulate from the water. Fluid enters the separator where it is drawn through tangential slots. These tangential slots further accelerate the flow to maximize the separation of solids. Particles are then separated from the fluid via centrifugal action. The heaver particles are drawn to the outer edges while the clean water remains in the center. This vortex then hits the deflection plate which causes the heavy particles to fall into the collection chamber and the clean water to go up through the vortex to the outlet.
The contaminants at the bottom of the collection chamber are removed by a Solids Recovery Vessel (SRV). The dirty water is drawn into the SRV which houses a simple sock filter. The filter collects the debris while the clean water goes back into the system, not down the drain. The dirty filter is cleaned by a maintenance technician and is put back in the SRV. No water is lost in order to remove the contaminants from the system.
The operation is best shown in a working demo. Lakos provides a great video of solids separator operation shown here:
Water Savings Example
So exactly how much water can you save with this simple change? Here is a simple 500 ton example:
A sand filter backflushes a minimum of 3 minutes/day. Higher contaminant collection can necessitate higher backflush times closer to 6 or 10 minutes/day.
Sand Filter Yearly Water Use:
-Minimum: (250 days/year) * (3 minutes/day) * (300 gallons/minute) = 225,000 gallons/year
-Higher Estimate:(250 days/year) * (10 minutes/day) * (300 gallons/minute) = 750,000 gallons/year
Centrifugal Solids Separator Yearly Water Use:
-Zero Gallons of water per year
By implementing the solids separator the system sees an immediate savings of 225,000 to upward of 750,000 gallons of water! This water savings also results in direct monetary savings for the property owner in water and sewage costs.
Efficient Water Use - No Lip Balm
The principles of operation for both filtration systems have shown that centrifugal solids separators are an effective method to save water over sand filters in HVAC systems. Many HVAC professionals and property owners already utilize this technology because they can justify the monetary savings while doing their part to conserve the Earth's precious resources. Now you can too.
Comments