Cooling water systems are prone to corrosion, scaling, fouling and microbial growth. These problems are interdependent and exist in every system; only their extent or degree varies.
Corrosion is the reversion of the metal to its natural stable state –metal oxide. This leads to metal loss and fouling due to iron oxide often necessitating costly replacement of equipment.
Scaling is the formation of deposits from the water soluble constituents. As water concentrates in the cooling water system due to recycle (operation at higher COCs), the saturation limits of hardness salts (and some others) are exceeded and precipitate in the system leading to deposit formation. This can reduce heat transfer directly affecting the production efficiency.
Fouling is the deposition of water insoluble constituents like dirt, sand, silt, oil, corrosion products and the like. The problem is aggravated in low velocity areas and besides deposit build up, can also result in under deposit corrosion.
Cooling water systems are an ideal environment for the growth of microbes. The pH is ideal for their growth. There is an abundance of nutrients and sunlight leading to their proliferation. If uncontrolled they can lead to voluminous slime build up, fouling and corrosion.
The extent of each of these problems is dependent on the system dynamics and water parameters. The above problems or even one of them can lead to costly plant down time and need to be effectively controlled.
The Wex range of cooling water treatment programmes include;
- Carbon steel and multi-metal corrosion inhibitors.
- Antiscalants and Antifoulants.
- Special Dispersants.
- Non oxidising Biocides.
- Chlorine activators.
- Chlorine Dioxide precursor and generator.
- Closed System treatment programmes (Nitrite/Molybdate/Phosphonate based)
- Potable water corrosion inhibitors.
- Single Drum corrosion, scale and deposit control products.
Some of Wex programmes widely used are,
- Inorganic phosphate based
- Metallic & non metallic
- All organic
- Soft water Molybdate based
- Eco friendly microbial
- Specialty polymeric dispersants
- Crystal distorters
- Closed Loop Nitrite/Molybdate