Cooling Tower Bleed Reclamation System
Client achieves reduced operational costs, and an improved carbon footprint by reclaiming cooling tower water.Background
Cooling systems are key to many cooling processes, one of which is office environment comfort cooling. Operating these cooling systems in an efficient manner is essential, to minimise running costs and maintain production whilst ensuring the water quality is controlled.
A requirement of cooling tower water treatment is to manage the increasing conductivity within the system by removing some of the high conductivity water (bleed) and replacing this with new make-up water. It is common practise for cooling tower controllers to send this bleed water to drain, and top-up with treated fresh water. This has an obvious cost to the operator in terms of water utility and environmental costs.
Sayvol work closely in partnership with our clients to understand their environmental drivers, water usage and efficiency targets. One way to assist as part of our added value service is to help to optimise the efficiency of such cooling systems, whilst minimising waste and negative financial and environmental impact. In order to assist in achieving environmental goals; Sayvol have engineered a way of reclaiming a percentage of the bleed water and re-use as make-up water to the system which reduces the amount of water used on-site.
Where practicable, such a bespoke installation saves cooling system operators money by reducing the ongoing cost of operation (OPEX).
Objectives
- Reduce client’s water usage through the cooling tower systems.
- Provide a Return on Investment (ROI) solution to reduce the client’s OPEX costs.
- Ensure the system can log data to prove efficacy in order to show reduced water usage.
- Work in partnership to deliver a project which reduces the building’s carbon footprint and embraces their Green Building policy.
Achievements
The Sayvol Cooling Tower Bleed Reclamation System was commissioned in line with our project plan and timeline, including training for on-site operatives. The system has been designed to recover over 60% of the bleed water which would otherwise go to drain.
By working closely with all interested parties, we have ensured the system is designed robustly, cost and payback calculated based on firm data points, and the system installed and commissioned with minimal impact to the client.
Reducing OPEX costs
%
Reduction in Water Wastage
Improved Carbon Footprint
System description
Our client manages a prestigious Central London investment bank, with a large commercial office building. On-site, the client has seven cooling towers which historically had been bleeding to sewer, with make-up water being softened mains water (from the site soft water).
These cooling towers provide comfort cooling to the office and welfare areas throughout the building, as well as offering cooling to utility areas such as kitchens and server rooms.
We had identified a significant potential saving in purifying and recovering this water for re-use in the cooling towers.
There are two primary savings to be realised through bleed recovery:
1. Reduced water going to sewer. The bleed water would be captured and not sent to drain instead being filtered and returned to the system.
2. Improved system cycles of concentration. The recovered water (above) is a lower conductivity than softened mains and therefore the cycles of concentration in the system can increase due to improved water quality.
Conclusions
- Client is actively inputting into their own environmental & green building commitments.
- Client is achieving a 45% reduction in water being sent to drain from the cooling tower system.
- Client achieving financial savings through reduced total operational costs & payback period. Estimated to save 4,500m3 of water per annum.
- Client is achieving an increase in the Cycles of Concentration in the cooling system based on
an improvement in the overall make-up water quality.