Chloropac® Technology

The expansion of Electrocatalytic Products in electrochlorination and marine ICCP applications spans over a period of 50 years.

Their dedication and commitment to design and engineering of unique systems and standard products for a wide range of application users, means that, with their application knowledge and technology development, they "Lead the World" in the electro-chemistry technologies of Chloropac and Capac products.

Why Biofouling Prevention?

Whenever seawater or freshwater is used as part of an engineering process -  in petrochemical works, electric power generating or desalination plants, offshore oil & gas production and in ships or other applications using water - biological fouling is an ever present problem.

Biological Fouling in Marine Water Systems   Examples of biological fouling in marine water systems- Clams, mussels, crustaceans, weeds, slimes and algae. Embryos of Crabs and Mussels etc will stay, when the seawater is not treated, to feed and rapidly grow to full size in a few months. Within the water system these organisms are invariably protected from their normal Predators.

Chloropac Overview

Invented and refined by Electrocatalytic engineers, C.P.A. technology is proven in long-term performance and reliability. It is superior to other technologies and others are now changing to follow our lead. The C.P.A. electrolytic cell assembly consists of two concentric titanium tubes between which salt water (seawater) flows. By passing electric current through the salt water, CHLOROPAC converts sodium chloride into sodium hypo chlorite, the active ingredient required for disinfection, sterilizing water and preventing organic fouling. CHLOROPAC C.T.E. “always clean” design is proven not to require acid wash or other electrode cleaning methods. This allows users of CHLOROPAC C.T.E. technology to operate at design output capacity at all times and therefore achieves the lowest life cycle cost of any system.

Chloropac Technology

1 - Two bipolar flat plate cells in series.
2 - Two concentric tubular bipolar cells in series.
3 - Electrolytic flows through the annular space between the liner and outer electrodes as shown by white arrows

Standard designs are available for a wide range of chloride ion concentrations including brackish water, or use of aquifer and bore hole saline waters applications. CHLOROPAC has a truly dimensional stable electrode gap without any deposit formation, which in other designs closes the electrode gap.

CTE Technology - Concentric Tubular Electrode

Concentric Tubular Electrode  A design that looks after itself!...
The CTE generating cells in Chloropac need no back flushing or periodic cleaning. The cell has been specifically designed to operate with turbulent high velocity over the total electrode surface, preventing precipitation of magnesium and calcium hydroxides, keeping the cell continuously clean of calcareous deposits.

Thousands of Chloropac cells, installed and producing sodium hypochlorite, are operating in excess of five years with no requirement for electrode cleaning.

Cells will need refurbishing or replacing as the anode coating is consumed however when a cell does begin to lose its anode coating it does not fail spontaneously but simply passes less current. This is a signal to remove it from the system and replace it with either a new or re-furbished cell.

The cost of biological fouling in water systems is a heavy one. Chloropac treats the water system to prevent bio-fouling by injecting a sodium hypochlorite seawater solution in to the main water flow to provide a hostile habitat in which organic life do not wish to remain and will continue with the water flow until the outfall of the system thereby returning to the sea or river.

CHLOROPAC C.T.E. Technology is proven to be the most advanced seawater electrolyzer cell design for safely producing sodium hypochlorite. Chloropac is technically superior equipment for energy efficient, long-term plant operation. CHLOROPAC produces in situ, a dilute, safe solution of sodium hypochlorite for direct injection into the water circuit. This advanced technology has freed thousands of users worldwide from the cost and danger of purchasing and handling chemicals associated with other types of technologies

CHLOROPAC C.T.E. Technology systems are designed for installation in unclassified (safe) areas and do not change the area classification. Accredited by SIRA with ATEX certification Chloropac is also designed and supplied for operation in electrically classified hazardous areas with full ATEX certification.

CHLOROPAC C.T.E. Technology provides users freedom from the necessary high maintenance of other technologies, which require regular cleaning of electrodes usually by Acid washing. Therefore why take on the responsibility of safety in operation, disposal and training required when purchasing, handling, transporting to and from and for storage of acid and its neutralizing agent.

With CHLOROPAC C.T.E. Technology we do not recommend any standby electrolyzer capacity. Other technologies ( see PPE Technology below ) which require off duty cleaning of the electrolyzer may recommend 3 x 50% installed capacity to enable continuous operation when one unit is offline for cleaning.

CHLOROPAC C.T.E. Technology electrolyzers incorporate grounding of the electrolyzer inlet and outlet to earth as a simple method to prevent stay current corrosion of valves and instruments upstream and downstream of the electrolyser.

P.P.E. Technology - Parallel Plate Electrode Cell Assembly

Parallel Plate Electrode Cell Assembly   CHLOROPAC PPE Technology was used to develop a low cost modular electrolyzer cell of large capacity required for Utilities applications where the life cycle operating costs are overruled by initial capital cost. Grown from the PPE Technology cell designs of OSEC and Pacpuri Potable water electrolysers developed in early 1980’s and sold world wide following their launch in 1986.

The CHLOROPAC PPE Technology electrolyzer range has capacities of 1,000 to 10,000 kg/day of equivalent chlorine.  CHLOROPAC PPE Technology cells will require regular acid washing to maintain operation. Each electrolyzer consists of one or more cells modules connected electrically and hydraulically in series. The cell modules have a design operating pressure of 7.5baarg at 50deg C and are tested to 1.5 times the system design operating pressure prior to shipment. Utilizing the increased back pressure when operating PPE cells minimizes gas volume, reduces electrode wear and improves power efficiency. 

The cell body is constructed from spiral wound GRVE with titanium end flanges designed to AMSE VIII and BS5500.

Electroctalytic's Chloropac PPE systems are supplied in modular construction designs for adaptable installations using pre design standard assemblies.

3D Design

3D Design

Chloropac systems are designed in 3D to provide the most suitable layout of equipment and easy access for maintenance and user friendly operation.  3D designs optimize the use of space and are essential for Chloropac design integration into many of our customers projects.

Chloropac Design Integration

Precision, Total Control of Chlorination

Fine control is possible, because the sodium hypochlorite output of the CHLOROPAC cell is directly related to the direct current passing through it,. The CHLOROPAC electrolyzer control is designed to give constant output at the desired set point, infinitely adjustable over the range 10-100%. This enables production to be maintained at the precise level required, irrespective of variable sea water feed conditions in pressure, temperature and salinity conditions. The control module also has a “step control” feature which will automatically adjusts the sodium hypochlorite production, depending on the number of main water pumps in service.

Compact, Modular, for Adaptable Installation

The key to CHLOROPAC’s installation design is the modular grouping of the component equipment. Cell modules may be installed separately according to availability of space and maintenance logic. For example, on ships the cells themselves may logically be located near or in the machinery room or bilge area with ship pipe work and pumps, while the naturally air cooled transformer rectifier and controls may be more conveniently placed near the electric generator flat.

A Constitution that Won't Shut Down in Cold Water

At around 10 to 14 °C and below, the rate of loss of some cell anode coatings is severely accelerated. For this reason many competitor systems are programmed to shut down or reduce their anode currents when these external sea temperatures are reached. This leaves many owners with their cooling water system substantially unprotected from marine fouling at these cold water temperatures. A significantly problem for many of ocean waters.

CHLOROPAC anode coatings are robust and resistant to tolerate raised anode potentials and are also designed to be operated at normal currents in cold-water seas without risk of accelerated wear loss. Therefore automatic cut out is not necessary with CHLOROPAC anode technology.

On-site Service Technologies

Electrocatalytic personnel have the ability, willingness and desire to share their knowledge to help resolve problems and to improve the installation and operation of all electrochlorination systems. Support is offered in pipe work sizing and layout, valve orientation and position, selection of materials, system control, operator and maintenance training and in upgrading of existing older installations.

Replacement Cells and parts are available for most system designs.

Electrocatalytic Health Care packages include:
a) Remote system monitoring and diagnostic interrogation via telemetry communication system to help reduce the costs of operation and instigate preventive maintenance programs.
b) Programmed long term Service contracts
c) Upgrading and Refurbishing.
d) Worldwide team of trained service engineers.

General Technical Information

Biological fouling is discriminated into Macro fouling and Micro fouling. Micro = Slimes, Algae and Weeds
Macro = Barnacles, Mussels, clams, Hydroids, etc

Electrochlorination in general means treatment by on-site generation of equivalent chlorine in the form of a low concentration of sodium hypochlorite in a solution of seawater or salt water and injecting this solution into the main water stream requiring treatment. Onsite generation removes the need for bulk storage of chemical. The capacity of the Sodium Hypochlorite generating system is determined by the chlorine demand of the main water stream to be treated and its residence time in the system to be protected which enables the equivalent chlorine dosing regime to be established and the equivalent chlorine per hour required to be calculated.

Dosing Regime
To protect the whole cooling water system from bio fouling it is important to maintain a trace of equivalent chlorine through out the system. The dosing regime is set up for each site in accordance with the local conditions in chlorine demand of the water supplying the system.  Depending on the residence time of the water flowing in the system and any critical equipment to protect (e.g. condenser) there may be a requirement to dose the system at additional points to just dosing at the intake.

Continuous dosing is critical to successfully keeping the water system clean and in addition it may be necessary to add dosing intermittently at a higher level than continuous because of local conditions (e.g. heavy slimes).