Abstract: Methods and compositions for cleaning and maintaining chemical, biological and radiological countermeasure washdown systems are disclosed. Systems are effectively cleaned by the removal of water scale, including deposits, sediment, microbiological scale, microinvertebrate fouling, and the like, from the inside surfaces of piping in the system. A section of the system is isolated for cleaning and an aqueous acidic cleaning solution is circulated through the fouled pipe section to be cleaned for a sufficient time and at a controlled pH to dissolve and loosen the scale. After cleaning all of the sections, the system is restored to operational readiness.

Abstract: Methods and compositions for cleaning and maintaining chemical, biological and radiological countermeasure washdown systems are disclosed. Systems are effectively cleaned by the removal of water scale, including deposits, sediment, microbiological scale, micro-invertebrate fouling, and the like, from the inside surfaces of piping in the system. A section of the system is isolated for cleaning and an aqueous acidic cleaning solution is circulated through the fouled pipe section to be cleaned for a sufficient time and at a controlled pH to dissolve and loosen the scale. After cleaning all of the sections, the system is restored to operational readiness.

Abstract: A method to chemically clean and immediately passivate a water distribution system to quickly form a passivation layer. The system may be a potable water system, a non-potable water system, a water well or a fire protection system such as a fire sprinkler system and may be treated with a biocide. A section of the system is isolated and chemically cleaned, then is immediately passivated using a high concentration of passivating agent. A passivating layer quickly forms, then the concentrated passivating agent is removed and a maintenance concentration of passivating agent is added. The cleaned and passivated section is restored to the system to provide improved water flow.

Abstract: A method to chemically clean and immediately passivate a water distribution system to quickly form a passivation layer. The system may be a potable water system, a non-potable water system, a water well or a fire protection system such as a fire sprinkler system and may be treated with a biocide. A section of the system is isolated and chemically cleaned, then is immediately passivated using a high concentration of passivating agent. A passivating layer quickly forms, then the concentrated passivating agent is removed and a maintenance concentration of passivating agent is added. The cleaned and passivated section is restored to the system to provide improved water flow.

Abstract: A method for controlled removal of carbonate blockage from interior walls of water conduit systems having substantial reduction in flow capacity. A section of the system to be cleaned is isolated and an aqueous liquid is circulated to establish baseline liquid flow rates. An acidic cleaning composition which removes the blockage but which generates carbon dioxide gas is then added under controlled conditions to a circulating aqueous cleaning solution. The fluid flow rates and pH are monitored throughout treatment. Adjustments are made if necessary to maintain a controlled amount of carbon dioxide gas liberated. The aqueous acid cleaning solution is circulated in an open loop system with continued addition of acid until the outflow rate decreases and once again equals the inflow rate. Substantial inorganic carbonate deposits are thus removed from water conduit systems while dangerous conditions due to excessive generation of carbon dioxide gas are avoided.

Abstract: A method of cleaning and maintaining potable water distribution systems which have reduced flow due to an increase of water scale deposits, sediment, and the like on the inside surface of the pipe is disclosed. An aqueous acidic cleaning solution is introduced and circulated through the pipe to be treated for a sufficient time to dissolve and loosen the scale and sediment, and the spent solution containing dissolved or suspended scale and sediment is flushed from the pipe to provide a cleaned pipe with improved water flow. It is also desirable to flush the water distribution pipe system with high pressure water after the treatment to remove loosened scale and sediment that was not removed during the circulation and flushing of the treating solution.

Abstract: A method of and system for removing blockage from pipes in vacuum waste systems in which fouled pipes in the existing vacuum waste system are configured into a closed loop. A cleaning solution is added to the loop. The cleaning solution is recirculated through the loop by pumping it to the ends of the fouled pipes and drawing it through the fouled pipes using the existing system vacuum equipment. The vacuum waste system may remain operational during cleaning.

Abstract: A process for pipe system cleaning and in-line treatment of spent pipe system cleaning solution prior to disposal. A cleaning solution is added to a fouled pipe system to clean the pipe system of scale or deposits. The spent cleaning solution is recirculated through the cleaned pipe system and a treatment agent is added to the recirculating spent cleaning solution. The treatment agent is recirculated until the spent cleaning solution is environmentally safe for disposal. The in-line treatment process minimizes the volume of treated spent cleaning solution and minimizes the time required to treat the spent cleaning solution.

Abstract: A method of and system for cleaning and maintaining water distribution pipes which have reduced flow due to an increase of water scale deposits, sediment and the like along the inside surface of the pipe includes a mobile cleaning unit which can be conveniently and easily connected to a pipe section to be cleaned. An aqueous cleaning solution is introduced and circulated in a first direction through the pipe section for sufficient time to dissolve and loosen scale and sediment. The flow direction of the treating solution is then reversed to break off or remove sediment or other tuberculated growth that has developed directionally with the direction of water flow in the pipe section. The turbulent flow in the opposite direction increases the effectiveness of the cleaning process in particularly troublesome and hard-to-clean pipe sections. The spent treating solution and other deposits are flushed from the pipe and the mobile cleaning unit to an appropriate waste stream.

Abstract: A method of removing chloride ion, a compound thereof, or flash rust (metal oxide) from a surface contaminated with chloride. The method includes the steps of providing a surface contaminated with chloride ion, a compound thereof or flash rust, and applying a dilute aqueous solution containing an active agent selected from the group consisting of an amine, anionic surfactant, organic carboxylic acid, organic sulfonic acid, and mixtures thereof to the surface in an amount sufficient to remove substantially all of the chloride ion, compound thereof, or flash rust from the surface.

Abstract: A method of cleaning and maintaining potable water distribution systems which have reduced flow due to an increase of scale, tuberculation, sediment, and the like on the inside surface of the pipe is disclosed. An aqueous acidic cleaning solution is heated and circulated through the pipe to be treated for a sufficient time to dissolve and loosen the scale and sediment, and the spent solution containing dissolved or suspended scale and sediment is flushed from the pipe to provide a cleaned pipe with improved water flow. It is also desirable to flush the water distribution pipe system with high pressure water after the treatment to remove loosened scale and sediment that was not removed during the circulation and flushing of the treating solution.

Abstract: A method of cleaning and maintaining a hot water heater tank contaminated with water scale and sediment by introducing an aqueous acidic treatment solution, retaining the acidic solution for a sufficient time to dissolve or suspend said scale and sediment, and then draining the spent solution containing the dissolved or suspended scale and sediment to provide a clean hot water heater tank.

Abstract: A method for removing scale and stains from the interior surfaces of a water-containing system having a reservoir, auxiliary equipment and piping, without having to drain the water from the system. The use of inhibited mineral acid allows the water to be circulated throughout the entire system, cleaning all interior surfaces without damaging them. Once scale and stains are removed, the water is neutralized.

Abstract: A method for the removal and prevention of scale using a soap composition of a 1:1 stoichiometric ratio equivalent of an acid and a base. The acid, for example, is an organic carboxylic acid or a mineral acid. The base is an amine or ammonia. The organic acids consist of formic, acetic, propionic, citric, glycolic, lactic, tartaric, polyacrylic, succinic, sulfonic, gluconic, benzoic, salicylic, and mixtures thereof. The mineral acids consist of hydrochloric, nitric, phosphoric, polyphosphoric, hydrofluoric, boric, sulfuric, and sulfurous, and mixtures thereof.

Abstract: A method of cleaning and maintaining water distribution systems which have reduced flow due to an increase of water scale deposits, sediment, and the like on the inside surface of the pipe is disclosed. An aqueous acidic cleaning solution is introduced and circulated through the pipe to be treated for a sufficient time to dissolve and loosen the scale and sediment, and the spent solution containing dissolved or suspended scale and sediment is flushed from the pipe to provide a cleaned pipe with improved water flow. It is also desirable to flush the water distribution pipe system with high pressure water after the treatment to remove loosened scale and sediment that was not removed during the circulation and flushing of the treating solution.