Cooling water chemistry solution1 December 2008
GE has put together a wireless integrated process water treatment package, known as Advanced Cooling Solution, that responds automatically and rapidly to unexpected system changes to reduce water consumption, corrosion, and total cost of ownership
The new package, designed for use on open recirculating cooling systems in a range of industries including power, refining and chemical processing, pulls together some new and some existing technologies for sensing, monitoring, dosing and reporting into a coherent automated system based on integrated wireless overall monitoring and control. The advanced monitoring and control capability comes from what GE calls its ‘revolutionary’ TrueSense direct polymer monitoring. The other main components are the wireless data monitoring and analysis and the (patented) GenGard chemistry, along with a raft of products for sidestream softening, filtering, and wastewater re-use. Its unique selling points are claimed to be active polymer measurement, the opportunity for water re-use and cost reporting. Designed for simple operation and rapid deployment, the ACS, says GE, can be fully installed and functioning within a matter of hours, which provides obvious benefits but also helps to reduce costs.
The aim was to produce a cooling system control with greater efficiency, reliability and predictability, reducing the total cost of ownership for the treatment programme and cooling assets. The system automatically responds to changes in water quality, tightening control without operator intervention. Swings in pH, high iron levels, clarifier carryover, and increased suspended solids loadings can all be rapidly detected and corrected.
To do this the package introduces ‘smart’ control systems, environmentally sensitive treatment chemistries, and wireless communications that automatically detect and immediately respond to unexpected events or water quality variations in recirculating cooling systems. By employing a fully integrated suite of monitoring equipment and chemistries, the system can make immediate adjustments to treatment polymers, thus optimising system performance.
Monitoring and control
The TruSense monitoring package is the first on-line monitoring and control combination that directly measures polymer levels. It is this feature that enables the system to react rapidly to system upsets and keep the system in balance. A complementary handheld unit for field use can test simultaneously for multiple parameters. The whole is backed up by a remote diagnostic system that can report in real time circuit parameters and key performance indicators, both technical and economic.
The patented GenGard chemistry employing a stress tolerant polymer that is fundamental to the ACS was developed in GE’s laboratories in China. It combines with halogen resistant polymers to create a complete corrosion and scale inhibition spectrum. It is effective under neutral or high pH conditions and is said to prevent deposition even under the most severe conditions, in particular during high pH excursions, or rapid changes (‘upsets’) in silt, aluminium, iron or phosphate levels.
The GenGard chemistry is said to provide further environmental benefits because it contains no heavy metal tracer and incorporates a halogen resistant azole. This greatly limits corrosion and the accumulation of metal ions in cooling water that is discharged to the environment. GenGard’s resistance to halogen-based oxidising biocides, such as chlorine, also helps to limit the usage of biocides, further reducing operational costs and improving corrosion protection.
With the addition of GE’s filtration technologies the ACS can also treat lower quality brackish or surface water sources and even recycled wastewater to a standard suitable for make-up water needs. In water scarce regions, this can be a critical process to conserve high quality potable water supplies and maximise cooling system up time.