research is ongoing |
Monograph on the theoretical foundations of magnesium sacrificial anode methods of corrosion control in lead and copper plumbing systems:
This year marks the fortieth anniversary of the development and commercial application for a method of water treatment which pioneered the use of a cathodic solution to the problem of corrosion control in municipal, industrial and domestic plumbing systems. The internal corrosion of lead-soldered copper water pipes and the attached fixtures or equipment is one of the most significant faced by advanced industrial societies. In combination with the consequences stemming from lead and copper exposure, it has now been estimated that, in the United States alone, the annual costs amount to tens of billions of dollars.
Corrosion of copper pipe-joint solder and lead bearing faucets can occur in a number of ways. Protective coatings like soluble silicates or orthophosphates may protect the metal surfaces, but they can crack or be damaged thereby localizing and accentuating the process (not to mention the potential hazards in handling these chemicals themselves).
A patented state of the art method of inhibiting such corrosion and creating lead-safe drinking water sources involves the employment of magnesium sacrificial anode technology. This system utilizes the phenomenon of passivation in which a thin magnesium layer is deposited on the inner metal surface of water pipes, preventing further electrochemical reactions. Magnesium anodes mounted within a housing which acts as the cathode will, when installed onto older or replacement water delivery lines, produce corrosion control without frequent monitoring, but simply occasional replacement of the anodes consumed by oxidation.
The unit itself, 'PROTEUS® II', once installed at or near the point where water enters the building is cost effective, since it is far easier to replace anodes then entire plumbing systems. A copper system in many instances is undersized (for economy) and it may contain a number of stressed areas due to physical bending and flexing during installation. These characteristics can cause cavitation and sponsor localized cathode sites (galvanic cells) in areas where they exist. Natural waters with a pH below 8.3 contain varying amounts carbon dioxide gas (the more acidic the water, the greater its carbon dioxide content) which combines with copper at the stress points to form soluble corrosion products (cupric carbonate). If uninhibited, the process of copper degradation proceeds until a section is structurally weakened and failure occurs.
It is during this process that potentially toxic lead from solder joints and attached brass fixtures is leeched out to produce (point-of-use) levels in drinking water which exceed safe standards (15 parts per billion).
The Proteus® electrochemical converter raises the pH of the water to 9.3 or above, neutralizing its acidity by the formation of magnesium hydroxide (MgOH). Oxygen has a negligible effect on the corrosion of copper, while temperature and total dissolved solid (TDS) content of the water will greatly influence the rate of corrosive attack within a system.
The Proteus® II electrochemical converter in effect, alters the composition of water passing though the unit, reducing its oxygen content and decreasing its acidity. The resulting increase in alkalinity will cause precipitation of the hydroxides of most metal ions that may be present. In addition to the reduction in soluble copper and toxic lead content, an improvement of taste (potability) is notable.
The Proteus® II units are designed for a flow rate in up to a 12 inch diameter pipe size, can operate on pressures up to 250 PSI, and may be installed and serviced by in-plant personnel, multi-unit building owners or the occupants of a single family dwelling.
Current studies done by the San Francisco Unified School District (1993 - 1994) demonstrate conclusively a significant decrease in the concentration of lead in school site drinking water fountains. Samples taken prior to the installation of the device had shown most to be above (some significantly above) recommended EPA levels resulting in the securing of fixtures by the district.
The replaceable magnesium sacrificial anode principal has had an established history as an electrolysis inhibitor. This method is used to protect ship hulls and bridges. Magnesium plates can be placed at intervals along a buried length of iron pipe, resulting in effective protection from corrosion.
The concept of its use as a plumbing control product was to become a practical commercial solution for water treatment not only on industrial hot water recirculating systems, but, with the development of a patented electrical component, tested and proven to work on single-pass-through cold water systems as well (see enclosed results: San Francisco Unified School District 1993 - 1994).
In 1987, following the passage of federal legislation, which included a ban on the use of lead solder for drinking water supply lines, both a problem and its solution were born.
Laboratory tests were performed on samples drawn from local schools, hospitals, offices and apartment buildings. Lead in quantities above safe levels (currently 15ppb) and in excess of that measurable in the municipal water source was being transferred by some buildings into the tap water. Higher lead concentrations would, in addition, result from evaporation and reduction by cooking procedures.
The application of a cathodic method of water treatment (Proteus® II) subsequently resulted in lead-safe water from a previously hazardous source. However, a new problem has surfaced, since Prop 65 provides for no implementation other than citizen enforcement...Would the business community voluntarily cooperate in protecting the health and safety of the public.
This year marks the fortieth anniversary of the development and commercial application for a method of water treatment which pioneered the use of a cathodic solution to the problem of corrosion control in municipal, industrial and domestic plumbing systems. The internal corrosion of lead-soldered copper water pipes and the attached fixtures or equipment is one of the most significant faced by advanced industrial societies. In combination with the consequences stemming from lead and copper exposure, it has now been estimated that, in the United States alone, the annual costs amount to tens of billions of dollars.
Corrosion of copper pipe-joint solder and lead bearing faucets can occur in a number of ways. Protective coatings like soluble silicates or orthophosphates may protect the metal surfaces, but they can crack or be damaged thereby localizing and accentuating the process (not to mention the potential hazards in handling these chemicals themselves).
A patented state of the art method of inhibiting such corrosion and creating lead-safe drinking water sources involves the employment of magnesium sacrificial anode technology. This system utilizes the phenomenon of passivation in which a thin magnesium layer is deposited on the inner metal surface of water pipes, preventing further electrochemical reactions. Magnesium anodes mounted within a housing which acts as the cathode will, when installed onto older or replacement water delivery lines, produce corrosion control without frequent monitoring, but simply occasional replacement of the anodes consumed by oxidation.
The unit itself, 'PROTEUS® II', once installed at or near the point where water enters the building is cost effective, since it is far easier to replace anodes then entire plumbing systems. A copper system in many instances is undersized (for economy) and it may contain a number of stressed areas due to physical bending and flexing during installation. These characteristics can cause cavitation and sponsor localized cathode sites (galvanic cells) in areas where they exist. Natural waters with a pH below 8.3 contain varying amounts carbon dioxide gas (the more acidic the water, the greater its carbon dioxide content) which combines with copper at the stress points to form soluble corrosion products (cupric carbonate). If uninhibited, the process of copper degradation proceeds until a section is structurally weakened and failure occurs.
It is during this process that potentially toxic lead from solder joints and attached brass fixtures is leeched out to produce (point-of-use) levels in drinking water which exceed safe standards (15 parts per billion).
The Proteus® electrochemical converter raises the pH of the water to 9.3 or above, neutralizing its acidity by the formation of magnesium hydroxide (MgOH). Oxygen has a negligible effect on the corrosion of copper, while temperature and total dissolved solid (TDS) content of the water will greatly influence the rate of corrosive attack within a system.
The Proteus® II electrochemical converter in effect, alters the composition of water passing though the unit, reducing its oxygen content and decreasing its acidity. The resulting increase in alkalinity will cause precipitation of the hydroxides of most metal ions that may be present. In addition to the reduction in soluble copper and toxic lead content, an improvement of taste (potability) is notable.
The Proteus® II units are designed for a flow rate in up to a 12 inch diameter pipe size, can operate on pressures up to 250 PSI, and may be installed and serviced by in-plant personnel, multi-unit building owners or the occupants of a single family dwelling.
Current studies done by the San Francisco Unified School District (1993 - 1994) demonstrate conclusively a significant decrease in the concentration of lead in school site drinking water fountains. Samples taken prior to the installation of the device had shown most to be above (some significantly above) recommended EPA levels resulting in the securing of fixtures by the district.
The replaceable magnesium sacrificial anode principal has had an established history as an electrolysis inhibitor. This method is used to protect ship hulls and bridges. Magnesium plates can be placed at intervals along a buried length of iron pipe, resulting in effective protection from corrosion.
The concept of its use as a plumbing control product was to become a practical commercial solution for water treatment not only on industrial hot water recirculating systems, but, with the development of a patented electrical component, tested and proven to work on single-pass-through cold water systems as well (see enclosed results: San Francisco Unified School District 1993 - 1994).
In 1987, following the passage of federal legislation, which included a ban on the use of lead solder for drinking water supply lines, both a problem and its solution were born.
- The problem: How to meet compliance with safe drinking water regulations by commercial operators found in violation without incurring the prohibitive costs of re-plumbing...
- The solution: Install cathodic corrosion control equipment onto the existing plumbing system and thereby inhibit the toxic lead exposure cost effectively
Laboratory tests were performed on samples drawn from local schools, hospitals, offices and apartment buildings. Lead in quantities above safe levels (currently 15ppb) and in excess of that measurable in the municipal water source was being transferred by some buildings into the tap water. Higher lead concentrations would, in addition, result from evaporation and reduction by cooking procedures.
The application of a cathodic method of water treatment (Proteus® II) subsequently resulted in lead-safe water from a previously hazardous source. However, a new problem has surfaced, since Prop 65 provides for no implementation other than citizen enforcement...Would the business community voluntarily cooperate in protecting the health and safety of the public.
