Cooling Tower Water Consumption [2021]

Evaporation is the reason cooling towers exist. To cool the remaining water, a small portion is turned into vapor, carrying heat away into the atmosphere.

Instead of manual blowdown, use automated sensors that only bleed the system when dissolved solids reach a specific threshold.

Now that we understand the mechanics, here are actionable strategies to reduce your cooling tower's water footprint. cooling tower water consumption

This is where water efficiency is truly won or lost. As water evaporates, it leaves behind minerals like calcium, magnesium, and silica. If these minerals are allowed to concentrate, they will scale the heat exchangers and destroy the system.

Cooling Tower Water Consumption: A Review of the Issues and Opportunities for Water Conservation Evaporation is the reason cooling towers exist

Running the cooling tower fans at full speed 24/7 is wasteful. Installing VFDs allows the fan speed to modulate based on the leaving water temperature. Slower fan speeds reduce drift and evaporation rates during cooler weather or low-load periods.

| Parameter | Typical Value | |-----------|----------------| | | ~1.0–1.2 gallons per minute (gpm) per 1 million Btu/hr of heat rejection (or ~0.1–0.12% of recirculation rate per 10°F range) | | Make-up water | 1.5–2.5% of recirculation flow rate for a 10–15°F range | | Blowdown (at CoC = 3–6) | 0.2–0.5% of recirculation rate | | Drift (modern eliminators) | 0.0005–0.005% of recirculation rate | | Total water use per ton-hour | ~1.8–3.0 gallons (air-cooled chillers use ~0 gallons for cooling tower) | Now that we understand the mechanics, here are

Modern cooling towers utilize drift eliminators—complex plastic baffles that force air to change direction, causing water droplets to separate and fall back into the basin. A well-maintained tower should have a drift loss of less than of the recirculating rate.

It sounds simple, but overflowing basins are a silent killer of water budgets. If the fill valve is malfunctioning or the basin is leaking, you are pouring money down the drain. Regular visual inspections are vital.

Cooling towers are a crucial component of many industrial and commercial facilities, used to dissipate heat from circulating water streams. However, they are also significant consumers of water, with a typical cooling tower using tens to hundreds of thousands of gallons of water per day. This paper reviews the current state of cooling tower water consumption, including the factors that influence water usage, the environmental impacts of cooling tower water consumption, and opportunities for water conservation. We also discuss various strategies for reducing cooling tower water consumption, including the use of water-efficient cooling towers, water recycling and reuse, and alternative cooling technologies.

Tiny droplets carried out by exhaust air. Modern towers with drift eliminators keep this very low (<0.001–0.005% of recirculation rate). Drift is usually less than 1–2% of total consumption.