Water is an ultimate sustainable resource. The hydrologic cycle works to continuously return water to nature for reuse. The challenge is to find enough usable water without overtaxing nature’s ability to replenish the local water supply.
As a large consumer of fresh water, boiler and cooling systems are obvious targets for water conservation efforts. When properly managed, reducing water usage for these systems can have the added benefit of reducing the total costs of operation. There are multiple strategies to help meet water-saving objectives, including management and control of water chemistry, makeup water pretreatment, use of alternative water sources, and equipment maintenance.
Impact of Cycles of Concentration
A core concept to efficiently operate boiler and cooling tower systems is “cycles of concentration.” The cycles of concentration measure the degree to which the dissolved-solid impurities in the makeup water are concentrated. If too low, water, energy, and treatment chemicals will be wasted. If too high, scale, corrosion, and other issues can reduce energy efficiency and decrease equipment life. Finding the best cycles of concentration for a particular boiler or cooling tower system helps optimize sustainability and costs of operation.
Cooling Tower Water-Saving Strategies
Cooling towers are used to remove heat from building HVAC systems and industrial processes, but require specialized maintenance to achieve maximum benefits.
- Optimize Cycles of Concentration: Optimizing cycles reduces water and chemical usage.
- Best Fit Chemical Treatment: Minimizes scale, corrosion, unwanted microbiological activity, and water usage.
- Automate Chemical Feed and Control: Automation to continuously monitor and adjust the water treatment program based upon changing system demands to achieve maximum system protection and minimum operating costs.
- Microbiological Control: Reduces insulating effects of biofilm formation, helps minimize corrosion, and is an integral part of risk management plans for pathogenic control.
- Pretreatment: Optimizes cycles and minimizes scale and corrosion (e.g., filtration, water softener).
- Acid Feed: Decreases scale-forming potential to increase cycles.
- Alternative Water Sources: Reduce water costs and help meet sustainability initiatives. Examples include:
- Air Handler Condensate
- Rain Water Harvesting
- Ground Water
- Blended Water
- Reverse Osmosis (RO) Reject Water
- Reclaim or Gray Water
- Site-Specific Reclaim Water
Boiler Water-Saving Strategies
Steam boilers burn fuel to turn makeup water into steam for space heating, process uses, power generation, and more. The quality of water used for makeup, the degree of system control, and the balance of waters within the system can directly impact water efficiency. Because energy is required to heat boiler water, water savings strategies also reduce energy usage.
- Optimize Cycles of Concentration: Optimizing cycles reduces water, fuel, and chemical usage.
- Best Fit Chemical Treatment: Minimizes scale, corrosion, and water usage.
- Automate Blowdown Control: Fine tunes boiler conductivity control to maintain proper cycles.
- Maximize Condensate Return: Recycles high-purity, hot water.
- Proper Deaerator Venting: Reduces boiler system corrosion.
- Functional Steam Traps: Decreases steam waste.
- Pretreatment: Optimizes cycles and minimizes scale and corrosion (e.g., water softener, dealkalizer, reverse osmosis, demineralizer)
Closed System Water Saving Strategies
Closed systems (chilled loops, closed loops, hot loops) are water systems that recirculate in a continuous loop where heat is added to one part of the system and then removed in another part without direct air contact or evaporation. Water loss is typically minimum with little makeup water needed.
- Reduce Water Losses: Decreases water usage, conserves treatment products, and minimizes introduction of unwanted microbiological activity.
- Minimize Corrosion: Reduces water loss, extends equipment life, and minimizes costs of operation.
- Filtration: Removes suspended solids to reduce corrosion, erosion, and deposit formation.
- Automate Chemical Feed: Ensures proper levels of chemical treatment are maintained to minimize corrosion.
- Eliminate Dead Legs: Identify and eliminate low to no-flow sections that house unwanted microbiological activity that can lead to corrosion.
Achieving more sustainable water treatment solutions while optimizing the total cost of operation requires a partnership approach with proven water treatment providers. Chem-Aqua has the knowledge and experience to help you evaluate and meet your efficiency and sustainability goals. Contact us to find out which sustainable solutions will help your facility conserve valuable resources.