Seven Hills International Limited


Hydro PurePlus – Water Treatment Device



Hydro PurePlus – A one of a kind Non Chemical Water Treatment Device

Evaporative cooling towers are popular considering they provide the most cost effective cooling technology for commercial air conditioning and industrial processes.

Water-side problems develop in the cooling water system depending on the quality of the fresh water supply.

  • Scaling

  • Bacteria & Biological growth

  • Corrosion

The presence of one or a combination of these factors results in increased water usage, downtime and maintenance cost thus reducing the overall efficiency of the process.

Calcium carbonate scale of just 1.5 mil thickness is estimated to decrease thermal efficiency by 12.5 %

The cooling water environment (warm water with high dissolved solids & dirt) is an excellent media for growth of microorganism, increases risk of legionnaire’s disease.

The effect of bio film on the power cost of cooling operations is significant. The conductivity of bio film is typically 0.2 btu/[hr(ft2)(F/in) which is substantially less conductive then the common calcium carbonate scale.

Therefore excessive energy use can still result from the presence of bio film though the system may be scale free.

To prevent these problems, Seven Hills has developed an innovative, non chemical device, Hydro PurePlus for water treatment.

Hydro PurePlus is non chemical, self operated device (no power or any chemical required) that can function inside the cooling tower water bath unaided and uninterrupted, 24 hours a day, 365 days a year.







Hydro PurePlus Device System Components & Operation


Uniquely designed Hydro PurePlus device



Calcium Carbonate dissolving

Specially designed and developed in ceramic, the Hydro PurePlus device provides unique water reduction functional characteristics to maintain a near perfect equilibrium of cooling water chemistry in the cooling tower bath. This reduction function improves water quality by dissolving Ca(CO3)2 to Ca(HCO3)2

Hydro PurePlus maintains water equilibrium

Ca(CO3)2 + CO2+ H2O ⇆ Ca(HCO3)2 + CO(*)

(*) Equation not complete.


Bacterial Growth Inhibition

The Cu ion is in a unique combination with ceramic in Hydro PurePlus device. Cu ion enters bacterial cells through attraction by negative bacterial ions. The Cu ion reacts with cell enzymes and prevents adenosine triphosphate activation while also working on protein binding.

This function inhibits the growth of bacteria, micro- organisms and algae.(**)


Corrosion Reduction

Hydro PurePlus maintains a perfect balance of water in cooling towers; the resulting reduction of scaling and bacterial growth significantly diminishes the corrosion of cooling tower material, construction and pipelines.



Unique Characteristics Of Hydro PurePlus Device & Benefits


  • Reduced water consumption

  • No hazardous chemicals used – 100 % cost saving on chemicals

  • Improved cycle of concentration

  • No expensive maintenance cost

  • No corrosion

  • Reduced cost of blown down water treatment (No chemical used to maintain water quality)

  • Improved system energy efficiency (a typical 10 – 30% reduction in Electricity consumption)

  • Stabilized operations

  • Improved worker safety & clean operation area as there is no issue of Legionella bacteria(**)

  • Reduced manpower & better quality results obtained.

(**)Performance depends on temperature.


Hydro PurePlus Device specification


Length – 50 cm
Height – 7 cm
Weight – 4.4 kgs


Hydro PurePlus Device recommendation

We recommend

One Hydro PurePlus device 10 RT (Refrigeration Tons) for moderate water treatment

Two Hydro PurePlus devices per 10 RT for high quality water treatment


Hydro PurePlus Device typical Installation and results at a glance

Hydro PurePlus Device impact on Heat Exchangers


Heat Exchanger before Hydro PurePlus Installation
Heat Exchanger after Hydro PurePlus Installation



Hydro PurePlus Device impact on Cooling Tower Pipes
Pipe before Hydro PurePlus Installation
Pipe after Hydro PurePlus Installation
After 6 Months
After 1 year



Hydro PurePlus Device impact on Cooling Tower bacterial effect
Cooling Tower external wall before Hydro PurePlus Installation
Cooling Tower external wall after Hydro PurePlus Installation
After 1 year



Hydro PurePlus Device impact on Cooling Tower Material of construction
Corrosion before Hydro PurePlus Installation
Corrosion after Hydro PurePlus
After 4 Months
After 1 year



Hydro PurePlus Device Boiler tube


Boiler tubes before Hydro PurePlus Installation Boiler tubes After Hydro PurePlus Installation
Before After 1 year



Hydro PurePlus Device Typical Installation



Chemical free Hydro PurePlus Device can help avoid the following.