marine cathodic protection
TRANSCRIPT
Marine Cathodic Protection
Marine Impressed Current Cathodic Protection (ICCP) Systems
CATHELCO LTD. ICCP IMPRESSED CURRENT CATHODIC PROTECTION (ICCP) SYSTEMS FOR THE MARINE INDUSTRY ............................................................................................................................ 3
CATHELCO LTD. ICCP IMPRESSED CURRENT CATHODIC PROTECTION (ICCP) HULL PROTECTION SYSTEMS FOR FPSOS & FSOS ........................................................................................ 8
CATHELCO LTD. ICCP IMPRESSED CURRENT CATHODIC PROTECTION (ICCP) SYSTEMS FOR MARINE SEMI-SUBMERSIBLES ................................................................................................................ 9
Marine Galvanic CP Materials
ALOLINE GALVANIC ALUMINUM ANODES BY FARWEST .................................................................. 11
ZINC SACRIFICIAL ANODES FOR SHIPPING & OFFSHORE INDUSTRIES BY FARWEST CORROSION CONTROL ........................................................................................................................... 19
Marine Growth Prevention & Anti-Fouling Systems
CUPROBAN MGPS MARINE GROWTH PREVENTION & ANTI-FOULING SYSTEM ............................ 28
CATHELCO LTD. MARINE MARINE PIPEWORK ANTI-FOULING SYSTEMS FOR FPSOS................ 31
CATHELCO LTD. MARINE PIPEWORK ANTI-FOULING SYSTEMS FOR SEAWATER LIFT PUMPS . 33
ELECTRICHLOR HYPOCHLORITE GENERATORS FOR ANTI-FOULING & MARINE GROWTH PREVENTION............................................................................................................................................. 34
Marine Electrolytic De-Scaling Systems
GALVOCLEAN™ ELECTROLYTIC DE-SCALING & CORROSION REMOVAL SYSTEM FOR MARINEBALLAST TANKS ...................................................................................................................................... 43
Marine Electrochlorination Systems
ELECTRICHLOR HYPOCHLORITE GENERATORS FOR ANTI-FOULING & MARINE GROWTH PREVENTION............................................................................................................................................. 44
Marine Cathodic Protection Monitoring
ELECTRO-GUARD MODEL 125 CATHODIC PROTECTION MONITORING STATION ......................... 53
Marine Galvanic Isolators
GALVANIC ISOLATORS (GI) BY DEI MARINE........................................................................................ 54
Cathelco Ltd. ICCPImpressed Current Cathodic Protection(ICCP) Systems for the Marine Industry
Preventing Hull Corrosion with ICCP Systems
Although modern hull coatings can provide some protection against corrosion, they seldom offer a complete solution. For this reason, most operators choose to protect their vessels with a purpose-designed impressed current cathodic protection system (ICCP).
Using an arrangement of hull mounted anodes and reference cells connected to a control panel, the ICCP system produces a powerful impressed external current to suppress the natural electrochemical activity on the wetted surface of the hull. This eliminates the formation of aggressive corrosion cells on the surface of plates and avoids the problems, which can exist where dissimilar metals are introduced through welding or brought into proximity by other components such as propellers.
An essential feature of Impressed Current Cathodic Protection (ICCP) systems is that they constantly monitor the electrical potential at the seawater-hull interface and carefully adjust the output to the anodes. Therefore, the system is much more effective and reliable than sacrificial anode systems, where the level of protection is unknown and uncontrollable.
By installing an ICCP system, operators can make significant cost savings in hull maintenance and achieve reductions in fuel costs by having a smooth hull surface. Furthermore, the system will safeguard the owner's investment and ensure greater safety through stronger hull integrity.
Cathelco Ltd. has developed ICCP systems for vessels of every type:
ICCP for container, cruise, tankers, and other ocean-going ships.
ICCP for steel-hulled supply, crew, ferries, tugs, yachts, work, fishing, and other commercial vessels.
ICCP for aluminum-hulled supply, crew, ferries, tugs, yachts work, fishing, and other commercial vessels.
ICCP for military vessels.
ICCP for water-jet propulsion systems.
ICCP for container, cruise, tankers & other ocean-going ships
Ships such as container vessels, VLCCs and bulk carriers are usually protected by forward
and aft systems.
Forward system. To provide a smooth hull profile, the forward system normally uses
circular or elliptical anodes of approximately 100 amps mounted port and starboard. Power can be supplied from a modular or thyristor
(SCR) control panel.
Aft system. Linear loop anodes are ideal for installation on large commercial vessels as they provide a high output from a relatively small surface area. Because of their powerful output, one 300 amp anode fitted on each
side of the hull gives effective protection. Alternatively, linear anodes can be fitted.
Generally, thyristor control panels are used for aft systems on larger vessels, as they are economical and incorporate comprehensive information systems.
ICCP for steel hulled supply, crew, ferries, tugs, yachts, work, fishing & other commercial vessels
The Cathelco Ltd. Minitek System uses the latest technology to protect steel-hulled craft against
corrosion. This is achieved by using a compact control panel and an arrangement of anodes
and reference cells which are flush mounted on the hull – so there is nothing to interrupt the
smooth profile or cause additional drag.
The current to the anodes is constantly monitored and adjusted to provide the
"optimum" level of protection at all times. This is far superior to the performance of sacrificial anodes where the amount of protection cannot
be easily verified and may be insufficient to prevent corrosion.
Anode life 15 years - unlike sacrificial anodes.
Reduced weight in comparison with sacrificial anodes.
Flush-mounted anodes to ensure smooth hull profile.
No maintenance required.
Self-diagnostic system.
Operates from 230V or 115V AC. electrical supply.
Control panel only measures 500 x 390 x 210 mm for systems up to 40 amps.
Lower yard installation costs than recessed sacrificial anodes.
Length,Approximate
SacrificialAnodes
ICCPSystem
WeightAdvantage
25 m 186 kg 40.5 kg 145.5 kg45 m 465 kg 52 kg 413 kg60 m 926 kg 85 kg 841 kg
ICCP for aluminum-hulled supply, crew, ferries, tugs, yachts work, fishing & other commercial vessels
Aluminum is generally regarded as a stable material which does not corrode easily.
However, when used in conjunction with other metals such as bronze propellers and steel
components, serious problems of hull corrosion can arise.
The Cathelco Ltd. Alutek System uses the latest technology to eliminate corrosion on aluminum
hulls. Unlike traditional sacrificial anode systems, it uses flush mounted, lightweight
anodes and advanced monitoring systems to provide the optimum level of protection. So there is nothing to detract from the smooth
lines of your craft or reduce its speed.
Flush mounted anodes keep the hull streamlined.
Reduced weight in comparison with sacrificial anodes.
Automatic system - constantly monitors and adjusts output.
Operates from 230V or 115V AC. electrical supply.
Monitoring electrodes - measure the electrical potential near the dielectric shield
Controlling anodes - measure the electrical potential at a remote point on the hull.
Shield sensors - detect changes in resistance at the coated aluminum/seawater interface.
Lower yard installation costs than recessed sacrificial anodes.
Length,Approximate
SacrificialAnodes
ICCPSystem
WeightAdvantage
25 m 80 kg 52 kg 28 kg45 m 200 kg 52 kg 148 kg60 m 400 kg 52 kg 348 kg95 m 600 kg 52 kg 548 kg
ICCP for military vessels
The Cathelco Ltd. Corrintec Division is a technological leader in the design and manufacture of ICCP systems for naval
vessels. Their equipment has been supplied to 22 navies around the world for frigates, guided
missile destroyers, fast patrol craft, submarines and fleet auxiliaries.
In addition to a long association with the British Royal Navy, Cathelco Ltd. has supplied equipment to the new generation of high-speed
vessels including the U.S. Navy's "X" Craft.
I-Shield and Patroltek by Cathelco Ltd. represent the latest systems in a continuing technological evolution based on the highest levels of product integrity, reliability and
performance.
Cathelco Ltd. now protects the USS Missouri. For the full article reprint, please see Cathelco Ltd. Protects Historic Naval Vessel.
ICCP for water-jet propulsion systems
The Cathelco Ltd. Jettek ICCP system provides a unique and highly effective corrosion
protection for fast craft. Its reliability has been proved on fast ferries and military high-speed craft around the world, superseding systems
solely based on "isolation" methods.
The Problem: Water jet tunnels are particularly vulnerable to corrosion because they are
constructed from dissimilar metals, typically aluminum and stainless steel, or high tensile
steel and stainless steel. Problems can arise at the interface of these materials resulting in rapid corrosion, which can put the safety and
structural integrity of the vessel at risk.
Most high-speed craft are fitted with "isolation" systems to prevent corrosive activity between the dissimilar metals. However, many have a history of repeated failure, indicating that "isolation"’ is not a particularly efficient or successful method of preventing galvanic
corrosion.
Cathelco Ltd. ICCPImpressed Current Cathodic Protection
(ICCP)Hull Protection Systems for FPSOs & FSOs
A Floating Production, Storage and Offloading vessel (FPSO) or a Floating Storage and Offloading (FSO) vessel
requires a specially designed Impressed Current Cathodic Protection (ICCP) hull corrosion protection
system because periods between drydocking are significantly longer than for normal vessels. Other
factors such as "current creep" on anchor chains also have to be taken into consideration.
On a conventional ship, there may be a 15% paint loss over a 5-year period, but on an FPSO paint loss may exceed 80% after a 20-year operational period at sea.
Therefore, the skill in designing an ICCP system for an FPSO relies on understanding these differences and using equipment which meets the demand for long
lasting reliability.
Cathelco Ltd. ICCP uses diver-change anodes and reference electrodes which can be changed from the outside of the hull, simplifying replacement. There is also the option of using Jotun diver-change circular
anodes and reference electrodes, which are designed with vulcanized rubber coatings to create a watertight
seal with the cofferdam for easy installation and replacement.
As FPSOs are stationary in the field, they are fitted with forward and aft systems, providing a 50/50 current output, unlike conventional vessels,
which have higher current demand around the stern. As with all offshore facilities demanding the highest levels of performance, reliability and safety, Cathelco Ltd. hull protection systems have a minimum 1.5 times redundancy factor built into the design,
subject to specification.
Through a comprehensive understanding of cathodic protection and technical innovation in equipment design, Cathelco Ltd. are maintaining their position as leaders
in hull protection for this fast developing area of offshore production.
Cathelco Ltd. ICCPImpressed Current Cathodic Protection
(ICCP)Systems for Marine Semi-Submersibles
ICCP Control Panels
Cathelco Ltd. offer a choice of modular or thyristor (SCR) control panels Impressed Current Cathodic Protection (ICCP) Systems for Marine
Semi-Submersibles. Thyristor panels can be used on systems of up to 1000 amps and combine cost effectiveness with rugged reliability.
Modular panels can be used on systems of up to 350 amps and have the advantage of being lightweight and compact. Both types of panels
incorporate computerized output displays, alarms and information systems
ICCP Reference Electrodes
Reference electrodes measure the electrical potential at the hull/seawater interface and feed a signal back to the control panel. They have zinc elements and are ‘diver changeable’ enabling them
to be replaced from the outside of the hull by a diver.
ICCP Anodes
A range of anode designs are available for offshore applications. These include rod anodes, flush mounted disc anodes and linear loop anodes which emit a powerful current from a relatively small surface area. All of the anodes are ‘diver changeable’, simplifying
replacement.
ALOLINE Galvanic Aluminum Anodesby Farwest
Aluminum anodes have long been used in the fight against corrosion. Applications for aluminum anodes include ship hulls, tank interiors, offshore structures, submerged
pipelines, piers, pilings, etc.
ALOLINE aluminum anodes are designed for optimum performance under a variety of environmental conditions and temperature ranges. Cast in different sizes and weights,
ALOLINE anodes provide maximum performance in seawater and brackish environments.
Typical Chemical Composition
Element Percentage
Indium (In)Zinc (Zn)
Silicon (Si)Copper (Cu)
Iron (Fe)Cadmium (Cd)Others, eachOthers, totalAluminum
0.016 to 0.02%4.75 to 5.75%0.08 to 0.12%
0.003% Maximum0.12% Maximum0.002% Maximum0.02% Maximum0.05% Maximum
Remainder
Performance Characteristics
Anode CapacityPotential (Calomel)Consumption Rate
1150 amp hours per pound (Minimum)1.080 volts (Minimum)
7.6 pounds per amp year
Available Sizes
ALOLINE anodes are available in the shapes and sizes shown on the following drawings and charts. Other sizes and shapes may be available
that are not shown in this information. If you do not see a particular anode you require, please contact Farwest for assistance.
AnodeNumber
Weight (lbs) Length (in) Width (in) Height CoreDimensions (in)Alum. Core La Lc Wb Wt H (in)
10FM 9 1 12 16 3½ 3½ 2½ 3/16 x1¼
20FM 18 2 20 25 3 4½ 2½ 3/16 x1½
29FM 26 3 24 29 4½ 5½ 2½ 1/4" x 1½
37FM 34 3 36 41 3 5 2½ 3/16 x1½
94FM 87 7 54½ 62 4 4½ 3¾ 1/4" x 1½
110FM 101 9 77 84 4 4½ 3 3/8 1/4" x 1½
144FM 135 9 72 84 7 8 3 1/4" x 1½
270FM 245 25 90 102 6¾ 7¼ 4 1/4" x 2½
AnodeNumber
Weight (lbs) Length (in) Width (in) Height CoreDimensions (in)Alum. Core La Lc Wb Wt H (in)
26RT 22 4 60 72 2 2 2 1/2
39RT 35 4 60 72 2 2½ 2¾ 1/2
89RT 80 9 86 98 2½ 3½ 3¼ 5/8
120RT 111 9 64 75 4 5 4 3/4
145RT 134 11 77 88 4 5 4 3/4
157RT 150 7 60 72 4¾ 5¼ 5½ 3/4
278RT 263 15 51 73 6¾ 7¼ 6½ 1
AnodeNumber
Weight (lbs) Length (in) Width (in) Height CoreDimensions (in)Alum. Core La Lc Wb Wt H (in)
205PT 175 30 24 48 8 9 9½ 3" Sch40
290PT 244 46 29½ 53½ 9 10½ 9½ 3" Sch80
320PT 287 33 68 80 6¾ 7½ 6½ 2" Sch80
351PT 313 38 77 90 6¾ 7½ 6½ 2" Sch80
375PT 325 50 96 120 5¾ 6¾ 6½ 2" Sch80
473PT 425 48 100 114 6¾ 7½ 6½ 2" Sch80
575PT 470 105 72 84 8 9 9½ 4" Sch80
668PT 548 120 84 96 8 9 9½ 4" Sch80
875PT 725 150 96 120 9 10½ 9½ 4" Sch80
AnodeNumber
Weight (lbs) Length (in) Width (in) Height CoreDimensions (in)Alum. Core La Lc Wb Wt H (in)
11FM 9 2 12 12 5 6 1½ 3/16 x1¼
40FM 35 5 18 17 9 9 2¼ 1/4 x 2
61FM 56 5 18 17 9 9 3 5/8 1/4 x 2
80FM 76 4 48 10 4 4 4 1/4" x 1½
95FM 91 4 72 13¾ 7 7¾ 2 1/4" x 1½
144FM 140 4 72 14 7 8 3 1/4" x 1½
284FM 280 4 72 14 7 8 6 1/4" x 2½
AnodeNumber
Weight (lbs) Length (in) Width (in) Height CoreDimensions
(in)Alum. Core La Lc Wb Wt Wc H (in)
158FM 140 18 40 52 5¾ 6¾ 18¾ 5½ 3/8 x 2
237FM 212 25 60 68 5¾ 6¾ 12¾ 6 1/2 x 2
Aluminum Condenser Anodes
AnodeNumber
Dimensions (in) Core TypeWeight (lbs)
Aluminum GrossC-13 8" x 8" x 2" 3/4" Pipe 12.5 12.7C-26 8" x 8" x 4" 3/4" Pipe 23 23.2
C-13C 8" x 8" x 2" 3/4" NPT Coupling 12.5 12.7C-26C 8" x 8" x 4" 3/4" NPT Coupling 23 23.2
C-2R5A 5" diameter x 2" 3/4" Pipe 3.5 3.7
Heater Treater Aluminum Anodes(also available in 3/8" eyebolt)
Aluminum Length (in)Weight (lbs)
Aluminum Gross30" 20.7 22.560" 39.4 41.2
8" Dia. x 18" Cylinder Aluminum Anode
Eyebolt Aluminum Anode4" Square Cross Section
9.8" Dia. Sphere Aluminum Anode
Zinc Sacrificial Anodesfor Shipping & Offshore Industries
by Farwest Corrosion Control
Characteristics
Farwest zinc anodes are cast in current U.S. Military Specification (Mil-Spec) and Special High Grade high
purity alloys. Farwest zinc anodes are the ideal corrosion protection solution where the use of
aluminum anodes is restricted, as in the upper areas of tanks.
Features & Benefits
Economical and Time-Tested, Farwest zinc anodes set the standard for affordable corrosion protection.
Optimal Composition, Quality & Fit are ensured with anodes designed and manufactured at our suppliers
foundry.
Comprehensive Range of hull, tank, engine room, bracelet and other anodes is available to suit virtually every marine application.
Pit-Guard Anodes stop corrosive pitting in cargo and ballast tanks simply and economically.
Farwest Zinc Anode Alloys include the latest Mil-Spec delivering trusted performance, as well as Special High Grade (SHG) for reliable protection wherever Mil-Spec is not required.
Immediate Delivery of large quantities of standard anodes is available from stock.
Custom Anodes can be produced to satisfy unique specifications.
Applications
Hulls of ships, barges, tugs and boats
Ballast tanks of tankers, ore carriers and freighters
Bulkheads
Piers and pilings
Submarine pipelines
Heat exchangers
Traveling screens
Installation & Operation
Farwest zinc anodes are normally clamped or welded into position from an integrated steel core. With proper installation, the anodes will operate efficiently and economically without
attention. They generate their own current and work silently and surely to control corrosion. Apart from routine inspection, no labor cost is involved after installation and no
electrical supply is required.
Farwest Zinc Anodes: Simple, Economical
Designed specifically for reliable performance under a variety of environmental conditions, Farwest zinc anodes operate effectively at both low and high temperatures. Farwest zinc
sacrificial anodes are performance-proven with over 40 years of research and commercial use.
Pier and Piling Anodes: PZ Series
Several different galvanized steel cores are available in this anode series. When ordering, specify which of the following cores is desired.
Type "E" - 1/2" diameter eyebolt in anodes weighing up to 200 lbs; 3/4" over 200 lbs.
Type "P" - 3/4" standard pipe in anodes weighing less than 250 lbs; 1" pipe 250 lbs and up.
Type "R" - 1/2" diameter rod.
Anode Pounds W H LCoreType
CurrentAmp-Yrs
PZ-50 50 2" 2" 48" E, R 2
PZ-100 100 3" 3" 44" E, P, R 4
PZ-150 150 4" 4" 36" E, P, R 6
PZ-250 250 9" 9" 12" E, P, R 10
PZ-250A* 250 4" 4" 60" E, P, R 10
PZ-350 375 7" 7" 30" E, P, R 15
PZ-500 500 9" 9" 24" E, P, R 20
*Pipe core for this anode is 3/4" standard pipe.
Hi-Amp Cast Plates
Solid hull anodes are available without cast-in mounting strips.
Anode Pounds W H LCurrentAmp-Yrs
M-23 22 6" 12" 1 1/4" 1
M-19 19 6" 12" 1" 0.75
M-10 10 6" 12" 1/2" 0.5
Condenser Anodes: CZ Series
These circular anodes conform to the latest modification of MIL-A-18001 and are available
with either of the following core configurations:
Type "A" - one 1/2" IPS galvanized steel pipe.
Type "B" - two 1/2" IPS galvanized steel pipes on 3 1/2" centers (not shown).
Anode Lbs Dia.CoreType
CZ-2 1 2" A
CZ-3 2 3" A
CZ-4 3 4" A
CZ-5 5 5" A
CZ-6 7 6" A
CZ-9 16 9" B
CZ-11 24 11" B
Custom Line
For special requirements, HI-AMP anodes for ballast tanks, piers and pilings can be furnished with a wide variety of cores and to the range of dimensions shown in the
accompanying table.
Cross Section LengthsNominal Weight
(lbs/in)1.4" x 1.4" 6" - 60" 0.5
2" x 2" 6" - 60" 1.02 1/2" x 2 1/2" 6" - 60" 1.5
3" x 3" 6" - 60" 2.34" x 4" 6" - 60" 4.25" x 5" 6" - 48" 6.57" x 7" 6" - 36" 12.89" x 9" 6" - 24" 21.0
9" x 10" 6" - 24" 23.410" x 10" 6" - 24" 26.0
Hull Anodes
LL-26 Hull Anode
Contains single galvanized steel longitudinal strap. Can be bolted
or welded to hull. Particularly suited for smaller ships, coastal
vessels, harbor tugs, etc. Farwest can add a mounting hole to each mounting strap.
Anode Lbs W H L Amp-yrsLL-26 26 4 1/2" 2 1/4" 14" 1
LL-48 Hull Anode
Contains single longitudinal galvanized strap for welding to
hull. Particularly suited for major ships, 10,000 DWT and upward. Farwest can add a
mounting hole to each mounting strap.
Anode Lbs W H L Amp-yrsLL-48 48 4 1/2" 2 1/4" 24" 2
Tapered M-24 Hull Anode
Contains two cast-in galvanized steel mounting straps. Farwest
can add a mounting hole to each mounting strap.
Anode Lbs W H L Amp-yrsTapered M-
2422.5 6 1/2" 1 1/4"" 14" 1
Military Anodes
The military anodes shown here conform to the latest
modification of mil spec MIL-A-18001.
Anodes in this series contain two cast-in galvanized steel
mounting straps (brassmounting straps are also
available) or two cast-in cored holes on 6" centers
Farwest can add a mounting hole to each mounting strap.
Anode Lbs W L H Amp-yrsM-24 22 6" 12" 1 1/4" 1
M-23-C 22 6" 12" 1 1/4" 1
M-47 42 6" 12" 2 1/2" 2
M-47-C 39 6" 12" 2 1/2" 2
The military anodes below contain a single cast-in galvanized steel mounting strap measuring 3/16" x 1 1/4" x 16". Farwest can add a mounting hole to each mounting strap.
Anode Lbs W L H Amp-yrs
M-12 11 3" 12" 1 1/4" 0.5
M-21 21 3" 12" 2 1/2" 1.0
A teardrop-shaped military anode containing a single. Cast-in galvanized steel straps. Farwest
can add mounting holes, such as two 3/8" diameter holes on 11" centers.
Anode Lbs W L H Amp-yrsM-6 5 3" 9" 1 1/4" 0.25
Ballast Tank Anodes
TZ Series
Anodes contain 1/2" diameter straight electrogalvanized steel core rod for direct welding or
assembly to two flat bards with "U" bolts as shown.
Anode Lbs W H La Lc Amp-yrsTZ-27 27 1.4" 1.4" 48" 60" 1
TZ-50 50 2" 2" 48" 60" 1
TZ-60 60 2" 2" 60" 72" 2.25
TZ-70 70 2 1/2" 2 1/2" 48" 60" 2.5
TZ-100 100 2 1/2" 2 1/2" 60" 72" 4
TZW Series
The core consists of two electro-galvanized steel flat
bars welded to a mild steel rod. Anodes can be clamped, welded
or bolted to a ballast tank structure.
Clamp Type Bolt Type Lbs W H La C Amp-yrsTZ-27-WC TZ-27WB 27 1.4" 1.4" 48" 24" 1TZ-50-WC TZ-50WB 50 2" 2" 48" 24" 2TZ-60-WC TZ-60WB 60 2" 2" 60" 36" 2.25TZ-70-WC TZ-70WB 70 2 1/2" 2 1/2" 48" 24" 2.5
- TZ-100WB 70 2 1/2" 2 1/2" 60" 36" 4
BTZ Series
Contains 1/2" diameter bent electro-galvanized steel core rod
on sizes up to 50 lbs for direct welding to structure. Anodes over
50 lbs have 5/8" diameter core rod. Use TZW series anodes where excessive vibration is
anticipated.
Anode Lbs W H La Lc Amp-yrsBTZ-27 27 1.4" 1.4" 48" 69" 1
BTZ-50 50 2" 2" 48" 69" 2
BTZ-60 60 2" 2" 60" 81" 2.25
BTZ-70 70 2 1/2" 2 1/2" 48" 69" 2.5
BTZ-100 100 2 1/2" 2 1/2" 60" 81" 4
Bracelet Anodes
Number ofSegments
Nom. PipeDiameter
4 20" - 36"4 or 6 30" - 36"
6 30" - 54"6 or 8 40" - 54"
8 40" - 72"
Q-AMP™ bracelet anodes are a family of products consisting of quadrants of multiple arc segments. Each segment contains cast-in, circumferentially oriented steel cores. Bracelets are assembled with 4, 6 or 8 units depending on pipe diameter. Q-AMP bracelet anodes are
superior to both semicircular bracelet assemblies in the larger sizes and multi-segment, external core assemblies because they offer:
More accurate sizing over pipe coatings to eliminate gaps that promote excessive wastage of the anode at the inside diameter of the bracelet.
Minimal distortion and "locked-in" stress when compared to conventional semi-circular bracelets for pipes of about 20"diameter.
The maximum arc length of each segment ranges from about 14" to about 27". Each segment contains at least one circumferentially-oriented steel core.
Cuproban MGPSMarine Growth Prevention
& Anti-Fouling System
Electrolytic anti-fouling system prevents barnaclesin seawater piping cooling systems.
Without MGPS anti-fouling system With MGPS anti-fouling system
Cuproban MGPS Overview
The Cuproban Marine Growth Prevention System (MGPS) prevents marine growth from accumulating and keeps piping clear of biofouling. It is a cost-effective marine anti-fouling and corrosion control system. It is ideal for use in marine seawater cooling systems. It is
used on ships, oil rigs, oil platforms, power stations, and elsewhere.
Without anti-fouling by Cuproban MGPS, marine growth, such as mollusks, barnacles, mussels, algae and slime enter the seawater system and find a spot where temperature, nutrients, pH factor and other environmental conditions are right for settling and breeding. Colonies can quickly develop, resulting in problems such as turbulence, blocked pipes and impaired heat
transfer efficiency. In extreme cases, marine growth fouling can become so serious as to completely obstruct the flow of seawater through cooling piping. Blocked pipes can also lead
to dangerous situations with fire-fighting equipment. Lesser cooling system complications include overheating, reduced efficiency, increased corrosion, and loss of vessel speed – a
serious situation since most vessels demand maximum speed. Cleaning of blocked pipes, or in many cases replacement of complete sections piping, can be a time consuming and
expensive problem.
The Cuproban MGPS marine growth prevention & anti-fouling system is electrolytic in action. The system consists of copper and aluminum (or soft iron) anodes strategically located in sea
chests or sometimes in-board, but as close to the sea water intake point as possible. One set of anodes is recommended
for each sea water service. The anodes are connected to a control panel that feeds a current to the anodes. The resultant
ions and floc produced by the anodes is carried by the sea water, spreads through the pipe work and creates an
environment that is distinctly unfriendly to the marine life. Any marine life larvae that enter the pipe line will not settle, but will pass right through to discharge. An added benefit is that the
aluminum hydroxide floc creates a protective film on the pipelines, thereby significantly reducing pipeline corrosion.
The release of copper ions is extremely small and is measured in micrograms per liter of seawater.
Cuproban MGPS Installation
Sea Chest Anodes Control Panel Control Module
MGPS anodes are preferably installed in a sea chest and secured with specially designed safety caps. Such anodes will have a design life coinciding with dry dock schedules. In-board
fitments in the pipeline or in strainers when anodes can be replaced at any time are also possible. The anodes are all wired to one or more common control panels that can also have
connections to the pump controlling the water flow.
Cuproban MGPS Features & Benefits
Simple installation.
Pressure tested safety caps.
Reliable, automatic anti-fouling with minimal attention from the crew.
Complete protection against biofouling.
Reduced corrosion.
Minimal power requirements.
Modular electronic control panel using one module per flow line.
Easy system expansion by adding modules.
Unique anode wear indicator feature in control panel tells when anodes need replacement.
Unique anode save feature controls current to the anode based on there being or not being flow in the pipeline. This considerably increases anode life when flow is intermittent.
Cathelco Ltd. Marine Marine Pipework Anti-fouling
Systems for FPSOs
Marine organisms can breed prolifically in the numerous seawater intakes serving engine cooling, product
processing, fire fighting and potable water supply services of a Floating Production, Storage and Offloading (FPSO)
vessel. It is essential that all of these functions be protected by an effective and reliable seawater Cathelco Ltd. pipework
impressed current antifouling system.
Biofouled water pipe
Seachest Mounted Anodes
Copper and aluminium anodes can be mounted in seachests if the scheduled drydocking period for the FPSO is less
than 5 years, assuming there is sufficient space availability.
Strainer Mounted Anodes
The advantage of strainer mounted systems is that the anodes can be
changed at any time without the need for drydocking. In these circumstances, Cathelco Ltd. recommend that some of
the treated water is fed back to the seachests to ensure thatthey are kept
free from fouling.
Electrolysis Tank Systems
If the drydocking interval is greater than 5 years, an electrolysis tank system may be the most practical option. In this case, a feed is taken from one of the seachests and pumped to the electrolysis tank housing the copper and aluminum anodes. The seawater is treated at a high dosage rate and then distributed via pipework to multiple seachests where it is diluted by the incoming flow and achieves a normal dosage rate to protect against bio-
fouling.
Effective and reliable anti-fouling protection.
Automatic – requires minimal attention.
Does not involve the use of chemicals.
Environmentally friendly.
Cathelco Ltd.Marine Pipework Anti-fouling Systems
for Seawater Lift Pumps
Marine organisms breed prolifically in relatively shallow water where offshore
structures are often situated. This makes seawater pipework particularly vulnerable
to blockages, which can have serious consequences for the efficiency of seawater cooling and fire fighting
equipment.
Pump Unit Construction
Cathelco Ltd. pump protection anti-fouling units are designed to be mounted at the
bottom of pumps, often inside the stilling tube or caisson. These marine growth prevention systems consist of special copper and aluminum anodes housed
within a steel framework and fed with an electrical current from a transformer /
rectifier. The anode mounting frame acts
as the cathode, creating a completely self-contained unit, which is electrically isolated from the pump using a specially designed isolation kit.
Controlled Dosing
Although the seawater is dosed to higher concentrations than sea-going vessels, this is sufficient to prevent marine growth and suppress corrosion within the pipework. The
Cathelco Ltd. unit is automatically activated when the pump is switched on, however, a low dosage is maintained at all times to keep the bottom of the pump and strainer area free
from bio-fouling.
Anode Life
The life of the anodes is calculated to coincide with the scheduled maintenance period for the pumps, typically at intervals of between 2 and 5 years.
Deck Mounted and Tank Systems
In some cases, it is not practical to fit anode units within stilling tubes due to lack of space or unusually high dosage requirements. An alternative is to provide a deck mounted
electrolysis tank with a pipework system to distribute the dosed seawater to the bottom of each pump, where it is carried throughout the pipework by the seawater flow.
ElectriChlor Hypochlorite GeneratorsFor Anti-fouling & Marine Growth Prevention
The safe alternative to chlorine gas chlorination systems to control marine growth
in cooling water equipment, water/wastewater treatment & water supply systems.
Overview
The control of bio-fouling and sanitizing water systems by chlorination has been proven to be the most effective method for water treatment. Hypochlorination from salty water provides an
effective anti-fouling method of water treatment that is safe for personnel and the environment.
The generation of sodium hypochlorite (bleach) from on-site hypochlorite generators is the safe anti-fouling and marine growth prevention alternative to chlorine gas chlorination
systems as the chlorine generated in the generator is locked up as sodium hypochlorite at concentrations below the threshold of hazardous materials (1%) mandated by the EPA.
Dual EL1-3 hypochlorite generators for 24 kg/hr watertreatment in Altamira combined-cycle power station
Applications
Electrichlor on-site hypochlorite generators provide sodium hypochlorite to control marine growth in industrial cooling water equipment, water/wastewater treatment in water supply
systems and for refineries and offshore production platforms in Class 1, Division 1 & 2 hazardous locations. Electrichlor hypochlorite generators are suitable for indoor locations, or
outdoors on a concrete foundation with a sunshade. However, in freeze conditions, indoor locations are recommended. Due to elements in seawater that can be affected by electrolysis, seawater is not recommended as the medium for producing hypochlorite for drinking water
applications.
Seawater Systems
In industrial and off-shore marine seawater cooling water systems, hypochlorite derived from seawater is introduced into the cooling water system to prevent bio-fouling in piping and
equipment.
In industrial plants such as power stations, chemical plants and refineries, seawater is usually drawn from a pit or sump through seawater supply pumps located close to a seawater inlet
pipe or channel.
The seawater to the hypochlorite generator(s) is piped from the downstream side of the seawater supply pumps to provide the salty water from which the hypochlorite is derived.
Seawater passing through the generator is converted to sodium hypochlorite in a constant flow “once through” process providing a concentration of up to 1500 mg/l of sodium
hypochlorite. The hypochlorite is collected in a degas/storage tank before being returned and diffused with the incoming seawater in the seawater supply pump(s) pit or sump. In most
applications 0.1 to 0.3 mg/l of free available chlorine above the seawater chlorine demand is sufficient to control marine growth in cooling water systems. The chlorine demand of
seawater can range from less than 0.5 mg/l in open ocean situations to 5 or 6 mg/l in coastal and harbor areas. In situations where the chlorine demand fluctuates, a shock treatment may
be necessary from time to time. Should shock treatment be required, it should be accompanied with a suitable de-chlorination method located before the seawater return to
ensure the local marine species are not affected by the release of over chlorinated seawater. The de-chlorination process can be controlled by measuring the free available chlorine with a
chlorine analyzer at the outlet of the seawater return system, and then injecting the correct amount of de-chlorination chemical automatically.
Due to the high levels of Ca and Mg in seawater that build up on the negative (cathodes) electrodes, cleaning will be required from time to time. To facilitate this, Electrichlor seawater systems are equipped with a cleaning system based on the use of sulphamic acid. Sulphamic acid is an inert, dry crystalline powder, similar to sugar and is universally available in 25, 50 and 100 kg bags that can be stored in a dry environment for up to 5 years. Cell cleaning is
achieved by circulating a 10% sulphamic solution through the hypochlorite generator for 40 minutes once weekly or after every 200 hours operation. As the powder is safe to handle when
dry, a minimal amount of protective gear is required.
Brine Systems
The generation of hypochlorite from brine is replacing gaseous chlorination systems in water and wastewater treatment plants around the world.
In these systems food grade salt (NaCl) is loaded into a brine saturator and fed with softened water. A saturated (26%) brine solution from the saturator is mixed with softened water to
produce a 3% brine concentration that is batch fed through the hypochlorite generator(s). The batch is recirculated several times to raise the concentration to 8000 mg/l and exhaust the
NaCl in solution. The batch is then dumped into a degas/storage tank from where it is injected into the water supply or wastewater systems.
As softened water is used in brine systems, only minimal acid cleaning is necessary, if at all. However, Electrichlor provides an integral acid cleaning system as a standard product with
brine systems, so that cleaning can be accomplished if/when required.
Electrolytic Cells
Materials
Electrichlor electrolytic cells are all titanium with DSA (dimensionally stable) anodes coated with MMO (mixed metal oxides). No other metals are used in the manufacture of Electrichlor
hypochlorite cells.
Description
Electrichlor electrolytic cells are highly efficient due to the patented monopolar, multipass circular configuration that allows a progressively longer residence time for the adsorption of Cl- into the outgoing hypochlorite solution (see Fig. 1). Electrichlor electrodes have an even
current density over all anode and cathode surfaces due to the unique physical and electrical design which further enhances the overall efficiency of the Electrichlor electrolytic cell, promoting long anode life. All wetted parts of the Electrichlor cell are MMO (Mixed Metal
Oxide) on anode active surfaces.Cells are manufactured such that the anode assembly can be removed easily without the use
of special tools; only a wrench is necessary for the complete disassembly. Should anodes need inspection or replacement, they can be dismantled in place and the anode assembly
returned for replating. Due to their long operational life, (10 years and beyond) spare anodes are not necessary to be held in inventory; however, should they need replating, they can be
returned to Electrichlor.Electrichlor electrolytic cells are guaranteed against defective parts for 12 months from startup and for 5 years for the MMO anode coating under normal operating conditions.
Hydrogen gas is a by-product of the sodium hypochlorite process. Hydrogen disassociates readily with water and can be completely disengaged by holding the gaseous hypochlorite in a degas tank for a minimum of 7 minutes. The degas tank is equipped with a blower to dilute the hydrogen with ambient air to below the threshold of the LEL (lower explosion level). The
hydrogen/air mixture is then exhausted to atmosphere.
Electrolytic Cells
As the water flow within the tubular electrolytic cell is tangential to any build up of Ca and Mg on the surface of the cathode tubes, the fluid flow will cause the build up to flake off and be
washed out through the system. This promotes self cleaning in Electrichlor electrolytic cells.
Types
There are two types of electrolytic cell design; monopolar (multiple poles) and bi-polar (one pair). Monopolar cells have all cathode surfaces reacting with an equivalent matching anode
surface, so that for each anode plate or tubular surface there is an equivalent cathode. In a bi-polar cell there is a single anode at one end of the cell and a single cathode at the other. A
series of parallel titanium plates with one side MMO coated are placed between the anode andcathode. When operating, with seawater flowing between the plates the dc current passes
from the anode to an uncoated titanium plate, through the titanium plate, and then exits from the surface of the MMO coating, across the seawater to the uncoated side of the next plate
and so on until the current reaches the cathode. Because the internal current paths cannot be predicted, the MMO coatings in bi-polar cells may suffer excessive wear rates and be prone to
premature failure.
6 kg/hr of equivalent chlorine generatorfor offshore platform in Gulf of Mexico
Equipment
All equipment installed in/on Electrichlor hypochlorite generators has been selected for 30 years service. Only quality equipment is installed to ensure the maximum life possible.
Materials
Electrichlor hypochlorite generators are equipped with materials to mitigate corrosion. Due to the nature of the process and the corrosive environment where this type of equipment is
installed, Electrichlor hypochlorite generators have been manufactured from non-corrosive materials.
Cell cubicles - weather resistant NEMA 4X (IP-54) 316L stainless steel
Skids - 100 x 50 mm 316L stainless steel
Degas Tank – FRP with a nexus veil
Pipework – schedule 80 CPVC
Valves – CPVC or PVC
Pumps – either magnetic drive FRP or titanium
Degas Blower – 316L stainless steel with non-sparking fan
Motors – TEFC or explosion proof in hazardous areas
Instruments – inert wetted parts or fitted with gauge isolator
Control Cubicle – weather resistant NEMA 4X ( IP-54) 316L stainless steel
Control System
Each hypochlorite generator is manufactured for “Stand Alone” service and therefore is equipped with an individual control system. This means that in locations where multiple units are installed, each unit can be operated independently and individually from its control station
or from a remote location over the customer’s DCS system.
The control cubicle is equipped with a PLC and a 12” color touch screen with graphic pages for operator interface and operation. Alarms are annunciated on an alarm page and operate a
red strobe light on top of the control cubicle.
Hydrogen Dispersal
Hydrogen generated in the electrolytic process and entrained with the hypochlorite, is allowed to settle in the degas tank for a minimum of seven minutes. Ambient air is blown into the top of the degas tank to reduce the hydrogen/air concentration to below the lower explosion level
of hydrogen. The mixture at a concentration of less than 1% hydrogen is then exhausted to atmosphere.
Acid Cleaning System
Each generator is equipped with a small acid tank and a recirculating acid pump. The acid tank is sized to allow the electrolytic cells to be cleaned. A sulphamic acid concentration of
10% is recirculated through the electrolytic cells for 40 minutes to remove Ca and Mg buildup on the negative electrodes. On the completion , soda ash is added to the liquid to neutralize
the solution and recirculated for a further 3 minutes. The system can then be drained and flushed and returned to service. Cleaning is conducted from the operator’s touch screen once
weekly, or after every 200 hours operation.
EL1-3 Mini Offshore Platform for Class 1, Div 2 Location
Hypochlorite Generators In Hazardous Locations
Electrichlor hypochlorite generators are suitable for installation in refineries and offshore production platforms in Class 1, Div. 1 & 2 hazardous locations. All electrical equipment that may cause a spark is installed in purged NEMA 4X enclosures that require instrument air or
inert gas connected to a purge control panel. Flameproof motors and intrinsically safe instruments are provided on pumps and equipment where required.
Recommended Performance Specification
The following information should be followed in selecting or specifying a sodium hypochlorite generator:
Cell construction – tubular of monopolar design.
All electrodes – titanium with DSA anode coating of MMO guaranteed for 5 years.
Removable anodes – without the use of special tools.
Hypochlorite output guarantee - >4.5kW/kg of equivalent chlorine with all auxiliaries operating.
12” color touch screen.
Equipment to be skid mounted – on 100 x 50 mm 316L SS channel.
Equipment housing materials to be weatherproof and non corrosive – FRP and 316L stainlesssteel.
Degas and acid tanks to be FRP or PVC.
Generator to be suitable for indoor or outdoor installation.
Pipework and valves to be schedule 80 CPVC/PVC.
Instruments to have either non-metallic wetted parts or be fitted with gauge isolators.
Integral sulphamic acid cleaning.
Hypochlorite Generator Selection Chart
Selecting an Electrichlor hypochlorite generator can be achieved from the Selection Chart below or by forwarding the following information to Farwest:
Flow rate of water to be chlorinatedLevel of chlorination (normal)Level of chlorination (shock)
Water analysis table (if possible)
m³/hourmg/litermg/liter
to include chlorine demand**
** Chlorine demand is the exact dosage of chlorine necessary (mg/liter) to kill all water-borne
bacteria, pathogens and algae, and not leave any excess (free) chlorine in solution.
Primary Flowm3/hr
(1) & (5)
Number ofModules
Kg/hr of Equivalent Chlorine GeneratorNormal
(2)Maximum
(3)Model
(4)Dimensions (m)(L x W x H) (6)
210031504200
111
123
---
EL1 MicroEL2 MicroEL3 Micro
2.6 x 1.4 x 2.22.6 x 1.4 x 2.22.6 x 1.4 x 2.2
630084008400
111
468
---
EL2 MiniEL3 MiniEL4 Mini
2.6 x 1.4 x 2.22.6 x 1.4 x 2.22.6 x 1.4 x 2.8
84001260016800
111
81216
-1317
EL1-2EL1-3EL1-4
3 x 1.4 x 2.83 x 1.4 x 2.83 x 1.4 x 3.2
21100252002940033600
2222
21252933
23283236
EL2-5EL2-6EL2-7EL2-8
3.8 x 2 x 2.83.8 x 2 x 2.83.8 x 2 x 3.23.8 x 2 x 3.2
37800420004620050400
3333
38424650
42465055
EL3-9EL3-10EL3-11EL3-12
4.6 x 2.4 x 3.24.6 x 2.4 x 3.24.6 x 2.4 x 3.24.6 x 2.4 x 3.2
54600588006300067200
4444
54586367
59636973
EL4-13EL4-14EL4-15EL4-16
5.4 x 3 x 3.25.4 x 3 x 3.25.4 x 3 x 3.25.4 x 3 x 3.2
71400756007980084000
5555
71758084
78828892
EL5-17EL5-18EL5-19EL5-20
6.4 x 3 x 3.26.4 x 3 x 3.26.4 x 3 x 3.26.4 x 3 x 3.2
882009240096600100800
6666
889296100
96100110112
EL6-21EL6-22EL6-23EL6-24
7.2 x 3.0 x 37.2 x 3.0 x 37.2 x 3.0 x 37.2 x 3.0 x 3
Notes:(1) Primary flow rate is 20,000 m³/h and requires an equivalent chlorine dosage of 3
mg/liter(2) Rated output(3) Maximum output from clean, undiluted seawater or salted potable water (for short
periods only)(4) Generator model based on 1 mg/liter of equivalent chlorine in (1)
For a dosing level of more than 1 mg/liter of equivalent chlorine in (1), multiply the dosing level required and select the appropriate model (4).
(5) For water temperatures over 25°C a derating factor is applicable. Consult Farwest for further information.
(6) Dimensions shown are nominal. Actual dimensions may vary due to site requirements and application.
Example:Multiply the primary flow rate by 3 = 60,000 m³/hr
Select the closest flow rate from (1) = 63,000
Select model number (4) EL4-15
GalvoClean™Electrolytic De-Scaling & Corrosion
RemovalSystem for Marine Ballast Tanks
The Problem of Corrosion Scale in Ballast Tanks
In the marine industry, the buildup of heavy layers of corrosion scale in steel ballast tanks can be a major
problem for ship operators. Ballast tanks are required to be in sound condition, and deterioration of ballast tank
walls may make a vessel un-seaworthy.
Corrosion scale needs to be removed from tank walls to allow for proper inspection of the structural steel and allow coating to prevent future corrosion. The three
conventional methods of removing tank scale are time consuming and costly:
Shot-blasting
Hydro-blasting
Manual removal
The GalvoClean™ Solution
Now there is a better solution. The GalvoClean method is an electrolytic process proven to reduce the man-hours and costs in removing scale by at least thirty percent (30%)
compared to conventional methods. The scale-to-steel interface is subjected to a chemical reaction which causes the release of hydrogen, thereby releasing the scale from the steel
substrate.
What the GalvoClean treatment achieves:
Clean Steel. The steel structure remains unaffected by the process.
Removal of Poor Coatings. Disbonded coatings are removed during the process, while bonded coatings are not disturbed.
Major Benefits of the GalvoClean™ System
No chemicals used.
No coating damage where the coating soundly adheres to steel.
No corrosion of exposed steel during the process. The magnesium used actually protects the steel.
Release of hydrogen only affects areas which need de-scaling.
Installation and dismantling procedures are very rapid. No time consuming welding required.
Electrical measuring equipment monitors the progress of de-scaling and allows recording.
New coatings can be applied immediately following procedure.
The GalvoClean™ Process
The GalvoClean system utilizes high potential magnesium ribbon and specially designed connection clamps. The magnesium ribbon
is connected inside the ballast tank so that all surfaces to be cleaned are in direct “sight” of the ribbon, as the process works
within a “line of sight” principle. This can be compared to installing an ordinary lighting system, where the requirement is to achieve no
shadows.
After installation of the ribbon is complete, the tank is filled with clean, low resistivity seawater. The system is left to work for
approximately seven to ten days, while being monitored electrically. Once the cleaning is complete, the tank is drained of all water, so that the scale and GalvoClean remnants can be removed from the
tank.
After draining, the tank is hydro-blasted using equipment capable of providing pressures between 300 and 500 bar (4,000 and 7,000 psi). This will remove any loose scale from horizontal surfaces as well as
any salt deposits, which have built up during the process. No disc sanding is required.
Once the loose scale has been removed from the tank and the area has completely dried, the steel can be recoated with no further treatment. In addition, cathodic protection anodes
should be installed to supplement the coating system to prevent further scale and corrosion.
ElectriChlor Hypochlorite GeneratorsFor Anti-fouling & Marine Growth Prevention
The safe alternative to chlorine gas chlorination systems to control marine growth
in cooling water equipment, water/wastewater treatment & water supply systems.
Overview
The control of bio-fouling and sanitizing water systems by chlorination has been proven to be the most effective method for water treatment. Hypochlorination from salty water provides an
effective anti-fouling method of water treatment that is safe for personnel and the environment.
The generation of sodium hypochlorite (bleach) from on-site hypochlorite generators is the safe anti-fouling and marine growth prevention alternative to chlorine gas chlorination
systems as the chlorine generated in the generator is locked up as sodium hypochlorite at concentrations below the threshold of hazardous materials (1%) mandated by the EPA.
Dual EL1-3 hypochlorite generators for 24 kg/hr watertreatment in Altamira combined-cycle power station
Applications
Electrichlor on-site hypochlorite generators provide sodium hypochlorite to control marine growth in industrial cooling water equipment, water/wastewater treatment in water supply
systems and for refineries and offshore production platforms in Class 1, Division 1 & 2 hazardous locations. Electrichlor hypochlorite generators are suitable for indoor locations, or
outdoors on a concrete foundation with a sunshade. However, in freeze conditions, indoor locations are recommended. Due to elements in seawater that can be affected by electrolysis, seawater is not recommended as the medium for producing hypochlorite for drinking water
applications.
Seawater Systems
In industrial and off-shore marine seawater cooling water systems, hypochlorite derived from seawater is introduced into the cooling water system to prevent bio-fouling in piping and
equipment.
In industrial plants such as power stations, chemical plants and refineries, seawater is usually drawn from a pit or sump through seawater supply pumps located close to a seawater inlet
pipe or channel.
The seawater to the hypochlorite generator(s) is piped from the downstream side of the seawater supply pumps to provide the salty water from which the hypochlorite is derived.
Seawater passing through the generator is converted to sodium hypochlorite in a constant flow “once through” process providing a concentration of up to 1500 mg/l of sodium
hypochlorite. The hypochlorite is collected in a degas/storage tank before being returned and diffused with the incoming seawater in the seawater supply pump(s) pit or sump. In most
applications 0.1 to 0.3 mg/l of free available chlorine above the seawater chlorine demand is sufficient to control marine growth in cooling water systems. The chlorine demand of
seawater can range from less than 0.5 mg/l in open ocean situations to 5 or 6 mg/l in coastal and harbor areas. In situations where the chlorine demand fluctuates, a shock treatment may
be necessary from time to time. Should shock treatment be required, it should be accompanied with a suitable de-chlorination method located before the seawater return to
ensure the local marine species are not affected by the release of over chlorinated seawater. The de-chlorination process can be controlled by measuring the free available chlorine with a
chlorine analyzer at the outlet of the seawater return system, and then injecting the correct amount of de-chlorination chemical automatically.
Due to the high levels of Ca and Mg in seawater that build up on the negative (cathodes) electrodes, cleaning will be required from time to time. To facilitate this, Electrichlor seawater systems are equipped with a cleaning system based on the use of sulphamic acid. Sulphamic acid is an inert, dry crystalline powder, similar to sugar and is universally available in 25, 50 and 100 kg bags that can be stored in a dry environment for up to 5 years. Cell cleaning is
achieved by circulating a 10% sulphamic solution through the hypochlorite generator for 40 minutes once weekly or after every 200 hours operation. As the powder is safe to handle when
dry, a minimal amount of protective gear is required.
Brine Systems
The generation of hypochlorite from brine is replacing gaseous chlorination systems in water and wastewater treatment plants around the world.
In these systems food grade salt (NaCl) is loaded into a brine saturator and fed with softened water. A saturated (26%) brine solution from the saturator is mixed with softened water to
produce a 3% brine concentration that is batch fed through the hypochlorite generator(s). The batch is recirculated several times to raise the concentration to 8000 mg/l and exhaust the
NaCl in solution. The batch is then dumped into a degas/storage tank from where it is injected into the water supply or wastewater systems.
As softened water is used in brine systems, only minimal acid cleaning is necessary, if at all. However, Electrichlor provides an integral acid cleaning system as a standard product with
brine systems, so that cleaning can be accomplished if/when required.
Electrolytic Cells
Materials
Electrichlor electrolytic cells are all titanium with DSA (dimensionally stable) anodes coated with MMO (mixed metal oxides). No other metals are used in the manufacture of Electrichlor
hypochlorite cells.
Description
Electrichlor electrolytic cells are highly efficient due to the patented monopolar, multipass circular configuration that allows a progressively longer residence time for the adsorption of Cl- into the outgoing hypochlorite solution (see Fig. 1). Electrichlor electrodes have an even
current density over all anode and cathode surfaces due to the unique physical and electrical design which further enhances the overall efficiency of the Electrichlor electrolytic cell, promoting long anode life. All wetted parts of the Electrichlor cell are MMO (Mixed Metal
Oxide) on anode active surfaces.Cells are manufactured such that the anode assembly can be removed easily without the use
of special tools; only a wrench is necessary for the complete disassembly. Should anodes need inspection or replacement, they can be dismantled in place and the anode assembly
returned for replating. Due to their long operational life, (10 years and beyond) spare anodes are not necessary to be held in inventory; however, should they need replating, they can be
returned to Electrichlor.Electrichlor electrolytic cells are guaranteed against defective parts for 12 months from startup and for 5 years for the MMO anode coating under normal operating conditions.
Hydrogen gas is a by-product of the sodium hypochlorite process. Hydrogen disassociates readily with water and can be completely disengaged by holding the gaseous hypochlorite in a degas tank for a minimum of 7 minutes. The degas tank is equipped with a blower to dilute the hydrogen with ambient air to below the threshold of the LEL (lower explosion level). The
hydrogen/air mixture is then exhausted to atmosphere.
Electrolytic Cells
As the water flow within the tubular electrolytic cell is tangential to any build up of Ca and Mg on the surface of the cathode tubes, the fluid flow will cause the build up to flake off and be
washed out through the system. This promotes self cleaning in Electrichlor electrolytic cells.
Types
There are two types of electrolytic cell design; monopolar (multiple poles) and bi-polar (one pair). Monopolar cells have all cathode surfaces reacting with an equivalent matching anode
surface, so that for each anode plate or tubular surface there is an equivalent cathode. In a bi-polar cell there is a single anode at one end of the cell and a single cathode at the other. A
series of parallel titanium plates with one side MMO coated are placed between the anode and cathode. When operating, with seawater flowing between the plates the dc current passes
from the anode to an uncoated titanium plate, through the titanium plate, and then exits from the surface of the MMO coating, across the seawater to the uncoated side of the next plate
and so on until the current reaches the cathode. Because the internal current paths cannot be predicted, the MMO coatings in bi-polar cells may suffer excessive wear rates and be prone to
premature failure.
6 kg/hr of equivalent chlorine generatorfor offshore platform in Gulf of Mexico
Equipment
All equipment installed in/on Electrichlor hypochlorite generators has been selected for 30 years service. Only quality equipment is installed to ensure the maximum life possible.
Materials
Electrichlor hypochlorite generators are equipped with materials to mitigate corrosion. Due to the nature of the process and the corrosive environment where this type of equipment is
installed, Electrichlor hypochlorite generators have been manufactured from non-corrosive materials.
Cell cubicles - weather resistant NEMA 4X (IP-54) 316L stainless steel
Skids - 100 x 50 mm 316L stainless steel
Degas Tank – FRP with a nexus veil
Pipework – schedule 80 CPVC
Valves – CPVC or PVC
Pumps – either magnetic drive FRP or titanium
Degas Blower – 316L stainless steel with non-sparking fan
Motors – TEFC or explosion proof in hazardous areas
Instruments – inert wetted parts or fitted with gauge isolator
Control Cubicle – weather resistant NEMA 4X ( IP-54) 316L stainless steel
Control System
Each hypochlorite generator is manufactured for “Stand Alone” service and therefore is equipped with an individual control system. This means that in locations where multiple units are installed, each unit can be operated independently and individually from its control station
or from a remote location over the customer’s DCS system.
The control cubicle is equipped with a PLC and a 12” color touch screen with graphic pages for operator interface and operation. Alarms are annunciated on an alarm page and operate a
red strobe light on top of the control cubicle.
Hydrogen Dispersal
Hydrogen generated in the electrolytic process and entrained with the hypochlorite, is allowed to settle in the degas tank for a minimum of seven minutes. Ambient air is blown into the top of the degas tank to reduce the hydrogen/air concentration to below the lower explosion level
of hydrogen. The mixture at a concentration of less than 1% hydrogen is then exhausted to atmosphere.
Acid Cleaning System
Each generator is equipped with a small acid tank and a recirculating acid pump. The acid tank is sized to allow the electrolytic cells to be cleaned. A sulphamic acid concentration of
10% is recirculated through the electrolytic cells for 40 minutes to remove Ca and Mg buildup on the negative electrodes. On the completion , soda ash is added to the liquid to neutralize
the solution and recirculated for a further 3 minutes. The system can then be drained and flushed and returned to service. Cleaning is conducted from the operator’s touch screen once
weekly, or after every 200 hours operation.
EL1-3 Mini Offshore Platform for Class 1, Div 2 Location
Hypochlorite Generators In Hazardous Locations
Electrichlor hypochlorite generators are suitable for installation in refineries and offshore production platforms in Class 1, Div. 1 & 2 hazardous locations. All electrical equipment that may cause a spark is installed in purged NEMA 4X enclosures that require instrument air or
inert gas connected to a purge control panel. Flameproof motors and intrinsically safe instruments are provided on pumps and equipment where required.
Recommended Performance Specification
The following information should be followed in selecting or specifying a sodium hypochlorite generator:
Cell construction – tubular of monopolar design.
All electrodes – titanium with DSA anode coating of MMO guaranteed for 5 years.
Removable anodes – without the use of special tools.
Hypochlorite output guarantee - >4.5kW/kg of equivalent chlorine with all auxiliaries operating.
12” color touch screen.
Equipment to be skid mounted – on 100 x 50 mm 316L SS channel.
Equipment housing materials to be weatherproof and non corrosive – FRP and 316L stainless steel.
Degas and acid tanks to be FRP or PVC.
Generator to be suitable for indoor or outdoor installation.
Pipework and valves to be schedule 80 CPVC/PVC.
Instruments to have either non-metallic wetted parts or be fitted with gauge isolators.
Integral sulphamic acid cleaning.
Hypochlorite Generator Selection Chart
Selecting an Electrichlor hypochlorite generator can be achieved from the Selection Chart below or by forwarding the following information to Farwest:
Flow rate of water to be chlorinatedLevel of chlorination (normal)Level of chlorination (shock)
Water analysis table (if possible)
m³/hourmg/litermg/liter
to include chlorine demand**
** Chlorine demand is the exact dosage of chlorine necessary (mg/liter) to kill all water-borne
bacteria, pathogens and algae, and not leave any excess (free) chlorine in solution.
Primary Flowm3/hr
(1) & (5)
Number ofModules
Kg/hr of Equivalent Chlorine GeneratorNormal
(2)Maximum
(3)Model
(4)Dimensions (m)(L x W x H) (6)
210031504200
111
123
---
EL1 MicroEL2 MicroEL3 Micro
2.6 x 1.4 x 2.22.6 x 1.4 x 2.22.6 x 1.4 x 2.2
630084008400
111
468
---
EL2 MiniEL3 MiniEL4 Mini
2.6 x 1.4 x 2.22.6 x 1.4 x 2.22.6 x 1.4 x 2.8
84001260016800
111
81216
-1317
EL1-2EL1-3EL1-4
3 x 1.4 x 2.83 x 1.4 x 2.83 x 1.4 x 3.2
21100252002940033600
2222
21252933
23283236
EL2-5EL2-6EL2-7EL2-8
3.8 x 2 x 2.83.8 x 2 x 2.83.8 x 2 x 3.23.8 x 2 x 3.2
37800420004620050400
3333
38424650
42465055
EL3-9EL3-10EL3-11EL3-12
4.6 x 2.4 x 3.24.6 x 2.4 x 3.24.6 x 2.4 x 3.24.6 x 2.4 x 3.2
54600588006300067200
4444
54586367
59636973
EL4-13EL4-14EL4-15EL4-16
5.4 x 3 x 3.25.4 x 3 x 3.25.4 x 3 x 3.25.4 x 3 x 3.2
71400756007980084000
5555
71758084
78828892
EL5-17EL5-18EL5-19EL5-20
6.4 x 3 x 3.26.4 x 3 x 3.26.4 x 3 x 3.26.4 x 3 x 3.2
882009240096600100800
6666
889296100
96100110112
EL6-21EL6-22EL6-23EL6-24
7.2 x 3.0 x 37.2 x 3.0 x 37.2 x 3.0 x 37.2 x 3.0 x 3
Notes:(1) Primary flow rate is 20,000 m³/h and requires an equivalent chlorine dosage of 3
mg/liter(2) Rated output(3) Maximum output from clean, undiluted seawater or salted potable water (for short
periods only)(4) Generator model based on 1 mg/liter of equivalent chlorine in (1)
For a dosing level of more than 1 mg/liter of equivalent chlorine in (1), multiply the dosing level required and select the appropriate model (4).
(5) For water temperatures over 25°C a derating factor is applicable. Consult Farwest for further information.
(6) Dimensions shown are nominal. Actual dimensions may vary due to site requirements and application.Example:
Multiply the primary flow rate by 3 = 60,000 m³/hrSelect the closest flow rate from (1) = 63,000
Select model number (4) EL4-15
Electro-Guard Model 125Cathodic Protection Monitoring Station
Monitors cathodic protection levels for boats, yachts & small ships in natural
waters. Allows potential corrosion problems to be spotted at a glance.
The Electro-Guard Model 125 Cathodic Protection Monitoring Station allows potential corrosion problems to be spotted at a glance. It provides easy-to-read indications of a
ship hull’s cathodic protection status by monitoring a reference electrode and transmitting that information to the ship control panel or other convenient monitoring
location.
Choice of three models:
Model 125A: For aluminum hulls, aluminum structures & components.
Model 125S: For steel hulls, steel or iron structures.
Model 125B: For fiberglass or wood hulls with bronze & stainless steel components & fittings.
Features:
Easy-to-read analog panel meter display.
Rugged, stable reference electrode.
Easy to install.
Suitable for sacrificial anodes or impressed current.
Accurate readings in all natural waters, including seawater, brackish & fresh water.
Continuous readings. There are no push-to-read buttons.
Optional models have a switch in the panel that allows for independent protection level readings of the shaft and propeller assemblies.
Powered by 12 to 24 Volts DC.
125 Installation Kit Includes:
Monitoring Station: An aluminum panel with a color-coded display that indicates the level of protection being provided by the cathodic protection system. The panel
measures 5 ¼" long by 3 ¾" high by 2 ¼" deep.
Reference Electrode: Zinc - 2-3/4" long x 1-3/4" wide with 1/2" thru-hull penetration.
Galvanic Isolators (GI)By DEI Marine
Stops galvanic corrosion caused by ship-to-shore power cables.
The Marine Galvanic Corrosion Problem
Whenever a boat is connected to shore power, the hull and drive system is connected to the shore grounding system and to other adjacent vessels (also connected to shore power) via the grounding conductor in the shore power cable. This connection, while required for safety, creates a galvanic corrosion cell involving the dissimilar metals between boats and between a boat and the shore grounding system, as shown in the following diagram below:
Four Components are Needed for Corrosion:
1) Anode – a metal surface which gives up metal ions (corrodes).2) Electrolyte – a medium which conducts ionic current between the anode and cathode.
3) Cathode – a metal surface that picks up metal ions.4) Metallic Bond – a metallic path that allows current to flow from cathode to anode.
The DEI Marine Solution
A simple method which virtually eliminates this galvanic corrosion problem is to insert an appropriately rated and certified DEI Galvanic Isolator in series with the grounding
conductor of the ship-to-shore power cable. The function of the Galvanic Isolator is to provide AC continuity of the grounding conductor (required for safety in the event of an AC
fault) and to block the flow of corrosion-causing galvanic current.
DEI Galvanic Isolators (GI) are fail-safe, solid-state DC isolation / AC coupling devices with ratings and characteristics that significantly exceed those of all known galvanic isolators
designed for marine applications. The proven fail-safe construction assures that the galvanic isolator never compromises the integrity of the grounding conductor, even in the
unlikely case of the product failing.
ABYC Certified
In the marine industry, the criteria for galvanic isolators is defined by the American Boat and Yacht Council (ABYC) Standard A-28,
which has a publication date of July 2008 and an effective date of July 2009. Due to recommendations to the A-28 galvanic isolator
standards committee concerning the need to retain safety grounding under all conditions, as required by the U.S. National
Electric Code for all similar applications outside of A-28, this standard now makes provision for fail-safe galvanic isolators.
To be considered "fail-safe," an independent laboratory must confirm that the isolator will either remain fully functional or remain a permanent, effective grounding path if it fails
when subject to the maximum current rating. Per the new A-28 standard, galvanic isolators meeting the fail-safe requirement will not require a monitoring system since the integrity of the grounding wire will not be compromised should the isolator fail. All galvanic isolators
not meeting the fail-safe criteria will still require a monitoring system to alert the boat owner that their grounding system may be compromised.
Fail-Safe Plus & Fail-Safe Max Technology
DEI offers a Fail-Safe Plus® (FSP) or Fail-Safe Max® (FSM) model for each rating except for the 100A and
200A models, for which only the Fail Safe Max model is offered. Fail-Safe Plus models not only meet the fail-safe test criteria in the new A-28, but also have considerably higher fault current ratings than are required and have very substantial lightning current
current ratings, which are not even required by A-28; hence, the "Plus" designation unique to DEI.
Fail-Safe Max models provide even higher AC fault ratings than Fail-Safe Plus models and will still be fully functional when tested to the A-28 fail-safe fault criteria, thereby providing the ultimate in performance; hence, the "Max" designation. The FSM models will fail in the
safe mode, at a level in excess of the A-28 fail-safe definition - a point at which the grounding conductor would have previously failed.
DEI Galvanic Isolator Features & Characteristics
Fail-safe construction with Fail-Safe Plus™ and Fail-Safe Max™ technology
Certified to ABYC A-28 July 2008 publication
Highest AC fault current ratings available
Ignition protected
Maintenance-free solid-state design
Rated for high levels of lightning current
Very low DC leakage current allowed
Galvanic Isolator Models
30A Galvanic Isolator
The 30A Galvanic Isolator is rated for all 30A through 35A shore power services and has been fully tested to meet the July 2008
publication of ABYC A28, the standard governing galvanic isolators in the US marine industry. The DEI 30A Galvanic Isolator comes in both Fail-Safe Plus® and Fail-Safe MAX®
versions, giving the customer increased options for safety. For international use, the 30A device has been rated to 35A to cover
applications using 32A shore power connections.
Rated for 30A through 35A use
Fail-safe construction featuring Fail-Safe Plus™ and Fail-Safe Max™ technology
Certified to ABYC A-28 July 2008 publication
CE Marine - Marine ISO 8846
No monitoring system required
50/60A Galvanic Isolator
The 50/60A Galvanic Isolator is rated for all 50A shore power services, as well as dual 30A shore power services, and has been
fully tested to meet the latest revisions to ABYC A-28, the standard governing galvanic isolators in the US marine industry. The DEI 50/60A Galvanic Isolator comes in both Fail-Safe Plus®
and Fail-Safe MAX® versions, giving the customer increased options for safety.
Rated to 50/60A (suitable for 50A and dual 30A shore power services)
Fail-safe construction featuring Fail-Safe Plus™ and Fail-Safe Max™ technology
Certified to ABYC A-28 July 2008 publication
CE Marine - ISO 8846
100A Galvanic Isolator
The 100A Galvanic Isolator is rated for all 100A shore power services and has been fully tested to meet the July 2008
publication of ABYC A-28, the standard governing galvanic isolators in the US marine industry. The DEI 100A Galvanic
Isolator comes in a Fail-Safe MAX® design, giving the customer premium performance and safety.
Rated to 100A
Fail-safe construction featuring Fail-Safe Max® technology
Certified to ABYC A-28 July 2008 publication
CE Marine-ISO 8846
200A Galvanic Isolator
The 200A Galvanic Isolator is rated for all 200A shore power services or dual 100A services. Although the ABYC A-28 standard
only addresses isolator ratings up through 100A, the DEI 200A Isolator has been designed with similar construction to the DEI 100A Isolator, but with a 200A continuous current rating (plus
overload). The DEI 200A Galvanic Isolator comes in a Fail-Safe MAX® design, giving the customer premium performance and safety.
Rated to 200A
Fail-safe construction featuring Fail-Safe Max™ technology
Typical Installation Schematic
