WO2020168007A1 - Procédés et systèmes de gestion de la corrosion dans des systèmes de circulation de conduits de batiments - Google Patents

Procédés et systèmes de gestion de la corrosion dans des systèmes de circulation de conduits de batiments Download PDF

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Publication number
WO2020168007A1
WO2020168007A1 PCT/US2020/018001 US2020018001W WO2020168007A1 WO 2020168007 A1 WO2020168007 A1 WO 2020168007A1 US 2020018001 W US2020018001 W US 2020018001W WO 2020168007 A1 WO2020168007 A1 WO 2020168007A1
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WO
WIPO (PCT)
Prior art keywords
pipe network
inert gas
water
operating
based building
Prior art date
Application number
PCT/US2020/018001
Other languages
English (en)
Inventor
Jeffrey T. Kochelek
Original Assignee
Engineered Corrosion Solutions, Llc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Engineered Corrosion Solutions, Llc filed Critical Engineered Corrosion Solutions, Llc
Publication of WO2020168007A1 publication Critical patent/WO2020168007A1/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B47/00—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass
    • F25B47/003—Arrangements for preventing or removing deposits or corrosion, not provided for in another subclass for preventing corrosion
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C35/00—Permanently-installed equipment
    • A62C35/58—Pipe-line systems
    • A62C35/60—Pipe-line systems wet, i.e. containing extinguishing material even when not in use
    • A—HUMAN NECESSITIES
    • A62—LIFE-SAVING; FIRE-FIGHTING
    • A62C—FIRE-FIGHTING
    • A62C35/00—Permanently-installed equipment
    • A62C35/58—Pipe-line systems
    • A62C35/68—Details, e.g. of pipes or valve systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L58/00—Protection of pipes or pipe fittings against corrosion or incrustation

Definitions

  • the present disclosure is directed to anti-corrosion protection in pipe networks of buildings and other structures.
  • a chiller system removes heat from a liquid via a vapor-compression or absorption refrigeration cycle. This liquid can then be circulated through a heat exchanger to cool equipment, or another process stream (such as air or process water). As a necessary by product, refrigeration creates waste heat that must be exhausted.
  • the basic components of most water chiller systems include a compressor that converts energy into compressed refrigerant.
  • Compressed refrigerant is transferred to a condenser that transfers heat from the refrigerant to a water coolant.
  • the compressed refrigerant changes state from a gas to a liquid in the condenser and then travels to an evaporator where it allowed to expand in the evaporator.
  • the expansion of the high pressure liquid refrigeration reduces the temperature of the evaporator.
  • the liquid to be cooled is pumped through the evaporator heat exchanger and heat is transferred to the refrigerant.
  • the low pressure vapor is carried back to the compressor and the cycle begins again for the refrigerant.
  • the coolant flows from the evaporator heat exchanger to the load where the heat is transferred to the coolant in the load heat exchanger and then returns back to the evaporator to repeat the cycle.
  • Chiller systems may be placed into service in large scale facilities to provide conditioned air for distribution in one or more portions of the facility. Chiller systems are also utilized in industrial process applications and integrated into process or laboratory equipment to cool products or machinery. They are widely used in connection with molding, metal working, welding, die-casting, machine tooling, chemical processing, and other industries, as well as to provide cooling for high heat generating specialized equipment. Water-based chiller units are a common choice in industrial process applications.
  • chiller systems operate by distributing chilled water heat exchanging structures, which cool air within the space associated with the heat exchanger by heat transfer. The heated water is then recirculated to the chiller to be recooled.
  • water chiller systems typically include a separate condenser water loop and are connected to exterior cooling towers to improve thermodynamic performance and may provide increased efficiency versus air-cooled and evaporatively cooled chiller systems.
  • These systems are typically installed as closed- loop systems, including the chiller unit, condenser, and pump station with recirculating pump, expansion valve, no-flow shutdown, and internal cold water control.
  • An internal tank helps maintain cold water temperature and prevents temperature spikes from occurring.
  • Closed- loop industrial water chillers recirculate clean water at a constant temperature and pressure to increase the stability and reproducibility of water-cooled machines and instruments.
  • water chiller systems utilize carbon steel - also referenced as black steel - piping or similar ferrous or cuprous materials.
  • closed loop chiller systems resulting in oxygen being trapped within the pipe network. Trapped oxygen reacts with the steel piping to cause corrosion thereby causing multiple negative results, including pitting pipe surfaces and corrosion by product debris (iron oxide hematite) that is then trapped within the closed system. Because of the typically highly complex piping arrangement in these systems, it is extremely difficult to simply vent trapped oxygen from the pipe networks.
  • the pipe networks are regularly drained and refilled for maintenance and other purposes. While oxygen that is trapped in the system while the system is closed during operation is slowly consumed by the corrosion reaction, each time the pipe networks are drained. Additionally, corrosion by product debris accumulating hear heat exchanger surfaces can interfere with heat transfer at these locations because of the insulating effect of the accumulated debris. These resulting “hot spots” further accelerate corrosion and eventually failure of the piping and/or heat exchanger components at these spots.
  • deterioration and corrosion of piping in closed-loop water chiller systems can involve several factors.
  • Second, depletion of biocide or other chemicals used to treat the water in the system in an attempt to control corrosion in the system due to the presence of tuberculation, organic matter, and microbiological organisms associated therewith may result in microbiological growth.
  • leaks can result from general corrosion and/or microbiologically influenced corrosion, such as oxidation by trapped air.
  • Microbiological influenced or induced corrosion can result when waterborne or airborne microbiological organisms, such as bacteria, molds, and fungi, are brought into the piping network of the protection system with untreated water and feed on nutrients within the piping system. These organisms establish colonies in the stagnant water within the system. Over time, the biological activities of these organisms cause significant problems within the piping network. Both ferrous metal and cuprous metal pipes may suffer pitting corrosion leading to pin-hole leaks. Iron oxidizing bacteria form tubercles, which can grow to occlude the pipes. Tubercles may also break free from the pipe wall and accumulate in particularly sensitives areas, such as in or near heat exchangers. Even stainless steel is not immune to the adverse effects of MIC, as certain sulfate-reducing bacteria are known to be responsible for rapid pitting and through-wall penetration of stainless steel pipes.
  • Gas may be discharged from the pipe network after supplying inert gas and prior to filling the system with water.
  • the supplying and discharging of inert gas from the inert gas source to the pipe network may be repeated before supplying water to the pipe network, thereby increasing concentration of inert gas in the pipe network or during draining of water from the pipe network to minimize oxygen from entering the pipe network.
  • the discharging of gas from the pipe network may include opening a drain valve in the pipe network.
  • an inert gas-based building pipe network inerting system including an inert gas source; at least one of a closed loop water chiller system and a fire protection system; the closed loop water chiller system further including a compressor; a condenser; an evaporator; a first pipe network; and a first vent in fluid communication with the first pipe network and configured to allow venting of gas from the first pipe network; the fire protection system further including a source of pressurized water; a second pipe network fluidly connected with the source of pressurized water; a sprinkler fluidly connected with the second pipe network; and a second vent in fluid communication with the second pipe network and configured to allow venting of gas from the second pipe network; a first fluid connection between the first pipe network and the inert gas source; and a second fluid connection between the second pipe network and the inert gas source.
  • a method of operating an inert gas-based building pipe network inerting system to protect the closed water chiller system and/or fire protection system includes the step of supplying an inert gas from the inert gas source into the first and/or second pipe network while the pipe network contains water.
  • Another method of operating an inert gas-based building pipe network inerting system to protect the closed water chiller system and/or fire protection system includes the step of supplying nitrogen from the nitrogen source into the first and/or second pipe network while the pipe network is filled with water.
  • Another method of operating an inert gas-based building pipe network inerting system to protect a closed water chiller system and/or fire protection system includes the step of supplying nitrogen from the nitrogen source into the first and/or second pipe network while the pipe network is drained of water.
  • Another method of operating an inert gas-based building pipe network inerting system to protect a closed water chiller system and/or fire protection system includes the steps of supplying an inert gas from the inert gas source into the first and/or second pipe network while the pipe network contains water; and venting trapped air and oxygen and/or pressurized inert gas within the first and/or second pipe network through the vent.
  • Another method of operating an inert gas-based building pipe network inerting system to protect a closed water chiller system and/or fire protection system includes the steps of supplying an inert gas from the inert gas source into the first and/or second pipe network while the pipe network is filled with water; and venting trapped air and oxygen and/or pressurized inert gas within the pipe network through the vent.
  • Another method of operating an inert gas-based building pipe network inerting system to protect a closed water chiller system and/or fire protection system includes the steps of supplying an inert gas from the inert gas source into the first and/or second pipe network while the pipe network is drained of water; and preventing air and oxygen from entering the pipe network through the vent.
  • Another inert gas-based building pipe network inerting system may further include an in line corrosion detector in communication with at least one of the first and second pipe network.
  • Another inert gas-based building pipe network inerting system further including a third pipe network configured for conducting a building supply of inert gas to various locations within the building and including at least one connection point for accessing the building supply of inert gas from the third pipe network.
  • Another inert gas-based building pipe network inerting system further includes a selector manifold between the inert gas source and the first and second pipe network and configured to selectively turn a flow of inert gas to each of the first and second pipe network on and off.
  • Another method of operating an inert gas-based building pipe network inerting system as further includes supplying inert gas from the inert gas source to the pipe network while draining water from the pipe network.
  • Another method of operating an inert gas-based building pipe network inerting system having a pipe network, a source of water for the pipe network, and an inert gas source connected with the pipe network includes the steps of supplying inert gas gas from the inert gas source to the pipe network to increase a pressure in the pipe network above atmospheric pressure; discharging gas from the pipe network after supplying inert gas to the pipe network; supplying water to the pipe network after discharging gas from the pipe network, thereby filling the pipe network with water and compressing inert gas in the pipe network; and venting compressed inert gas from the pipe network using a venting assembly configured to vent gas and not water from the pipe network while supplying water to the pipe network.
  • Another method of operating an inert gas-based building pipe network inerting system further includes repeating supplying inert gas and discharging gas from the pipe network prior to supplying water to the pipe network, thereby increasing concentration of inert gas in the pipe network.
  • Another method of operating an inert gas-based building pipe network inerting system includes repeating supplying inert gas and discharging gas from the pipe network prior to supplying water to the pipe network, until the inert gas concentration in the pipe network is established at a specified level.
  • Another method of operating a nitrogen-based building inerting system includes venting compressed nitrogen gas when pressure in the pipe network is above a set point pressure level.
  • FIG. 1 is a schematic drawing of a first exemplary closed loop water chiller system.
  • FIG. 5 is a schematic drawing of a yet another embodiment of a closed loop water chiller system incorporating an inert gas source, vent and inline corrosion detector as described herein.
  • Fig. 6 is a flow diagram of an inerting process for a closed loop water chiller system and/or a wet pipe fire protection system.
  • FIG. 9 is a schematic illustration of a second embodiment of a building nitrogen supply system.
  • nitrogen pressure may be set to approximately 30 PSIG and set point pressure of back-pressure regulator set to approximately 50 PSIG.
  • Drain valve is closed and nitrogen valve opens to fill pipe network with nitrogen rich air 58.
  • Nitrogen valve is then closed to prevent additional gas injection.
  • the technician may then sample the relative concentration of oxygen and nitrogen at sample port by opening port and allowing air to flow through tube for a sufficient time, such as several minutes, to allow levels to stabilize 60.
  • a manual or automatic oxygen meter can then be connected to port to achieve continuous or intermittent oxygen readings.
  • Nitrogen concentration may be inferred at 60 by subtracting the oxygen concentration percentage from 100%.
  • the relatively high pressure of the water such as between approximately 76 PSIG and 150 PSIG, compresses the nitrogen rich air in pipe network to a fraction of its volume and raises the pressure of the air above the set point of back-pressure regulator.
  • This causes back pressure regulator 36 to discharge the nitrogen rich air until essentially all of the air is depleted from the system at which time air vent closes in the presence of water.
  • Back pressure regulator then closes to prevent high oxygen rich air from entering the pipe network when it is subsequently drained of water.
  • the pipe network 112 further includes a venting assembly 132 for selectively venting air from pipe network 112.
  • venting assembly 132 vents air and not water from the pipe network in order to remove at least some of the air from the pipe network when the pipe network is filled with water in the manner described in U.S. patent application Ser. No. 12/615,738, filed on Nov. 10, 2009, entitled AUTOMATIC AIR VENT FOR FIRE SUPPRESSION WET PIPE SYSTEM AND METHOD OF VENTING A FIRE SUPPRESSION WET PIPE SYSTEM, the disclosure of which is hereby incorporated herein by reference.
  • venting assembly 132 is made up of an air vent 134 and an airflow regulator 135 (Fig. 11).
  • Air vent 134 is connected with the pipe network 112 and discharges to airflow regulator 135.
  • airflow regulator 135 is in the form of a back-pressure regulator 136.
  • Back-pressure regulator 136 responds to the pressure in the pipe network 112 by discharging air through air vent 134 that is above a set point pressure of the back-pressure regulator.
  • back-pressure regulator 136 includes a pressure gauge 137 that displays the pressure supplied to the back-pressure regulator and an adjustment knob 138 that allows the set point to be adjusted.
  • Venting assemblies including manually operated, electrically operated, and redundant vents, and methods of venting piping networks, suitable for use in pipe networks as described herein are further described in U.S. Patent No. 8,636,023, issued January 28, 2014, U.S. Patent No. 9,717,935, issued August 1, 2017, and U.S. Patent No.9, 884, 216, issued February 6,2018, the entire disclosures of each of which are hereby expressly incorporated by reference
  • a method of installing a corrosion monitoring device in a chiller system includes removing a section of the pipe from the piping network of a chiller system to create two pipe ends with a space between, positioning the corrosion monitoring device in the space, and coupling the corrosion monitoring device to the two pipe ends.
  • a method of monitoring corrosion within a chiller system having a pipe, and structure coupled to the pipe and defining a sealed chamber between the structure and the pipe includes sensing, with a pressure sensor, a pressure within the sealed chamber. The method also includes detecting a change in pressure within the sealed chamber, corresponding to a breach of a pipe wall of the sealed chamber. The method further includes generating a signal in response to detecting the change in pressure within the sealed chamber.
  • a method of monitoring corrosion within a chiller system having a pipe, and structure coupled to the pipe and defining a sealed chamber between the structure and the pipe includes sensing a parameter associated with the sealed chamber, and detecting a change in the parameter associated with the sealed chamber, corresponding to a breach of a pipe wall of the sealed chamber. The method also includes generating a signal in response to detecting the change in the parameter associated with the sealed chamber.
  • the nitrogen source 200 may have a single output 230 that is routed to each system 210 and 220 through a selector valve 240 that allows building management to more specifically direct the flow of nitrogen to the various systems desired to be supplied by the nitrogen source 200.
  • the selector valve 240 may be electronic or mechanical, and it may be locally controlled at the selector or remotely operable from a building, complex or plant control room or station. The selector valve 240 may direct the flow of nitrogen from the nitrogen source 200 to one or multiple systems.
  • a building (or plant or complex) nitrogen supply pipe network 250 may also be incorporated into the system.
  • the nitrogen supply pipe network 250 delivers nitrogen to multiple connection locations within the building (or plant or complex) for use in any desired processes or other uses.
  • each connection location associated with the nitrogen supply pipe network 250 is provided with a quick connect/disconnect connection to facilitate connection of equipment to the nitrogen supply pipe network 250.
  • a number of quick connect formats may be utilized, including, for example, industrial, automotive, or ARO type interchanges, pipe unions, or other such connections.
  • sliding collar couplings such as a ball- lock, roller-lock, pin lock, flat face, bayonet, ring-lock, or cam-lock couplings may be used. Electric, mechanical, manual, automatic, or remotely controlled shut-off valves may also be incorporated into these connections to provide further flow control options at the connection point.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Pipeline Systems (AREA)

Abstract

Un système de réseau de conduits de bâtiments et un procédé de fonctionnement d'un système d'inertage de réseau de conduits de bâtiments comprennent la fourniture d'une source de gaz inerte, un système de refroidisseur d'eau en boucle fermée et/ou un système de protection incendie. Le système de refroidisseur d'eau en boucle fermée comprend un compresseur, un condenseur, un évaporateur, un premier réseau de conduits et un premier évent en communication fluidique avec le premier réseau de conduits. Le système de protection incendie comprend une source d'eau sous pression, un second réseau de conduits en communication fluidique avec la source d'eau sous pression, un gicleur d'incendie relié de manière fluidique au second réseau de conduits, et un second évent en communication fluidique avec le second réseau de conduits. Il existe également un premier raccordement fluidique entre le premier réseau de conduits et la source d'azote, et un second raccordement fluidique entre le second réseau de conduits et la source d'azote. Une source de gaz inerte, telle qu'une source de gaz d'azote, est raccordée aux présents réseaux de conduits et/ou de préférence à tous les réseaux de conduits. Un gaz inerte est distribué de la source de gaz inerte au réseau de conduits. De l'eau est amenée dans le(s) réseau(x) de conduit(s), le(sp) remplissant sensiblement et comprimant le gaz inerte dans celui-ci (ceux-ci).
PCT/US2020/018001 2019-02-12 2020-02-12 Procédés et systèmes de gestion de la corrosion dans des systèmes de circulation de conduits de batiments WO2020168007A1 (fr)

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US201962804433P 2019-02-12 2019-02-12
US62/804,433 2019-02-12

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2585178B1 (fr) * 2010-06-22 2023-08-23 Engineered Corrosion Solutions, LLC Haute protection anticorrosion à l'azote ou autre gaz inerte dans un système de protection contre l'incendie à canalisations humides

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100263882A1 (en) * 2009-04-16 2010-10-21 South-Tek Systems System and method for fire protection system corrosion mitigation
WO2011056580A2 (fr) * 2009-10-27 2011-05-12 Fire Protection Systems Corrosion Management, Inc. Conduit d'évacuation de gaz de décharge commandé et procédé pour la réduction de la corrosion dans un système d'extincteur automatique de protection contre le feu sec
US20110226495A1 (en) * 2008-09-15 2011-09-22 Fire Protection Systems Corrosion Management, Inc. High nitrogen and other inert gas anti-corrosion protection in wet pipe fire protection system
US8141620B1 (en) * 2007-02-26 2012-03-27 United States Thermoelectric Consortium (USTC) Method for conditioning a cooling loop of a heat exchange system
US20140048290A1 (en) * 2012-08-20 2014-02-20 South-Tek Systems, LLC Deoxygenated Water Fill for Fire Protection System

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8141620B1 (en) * 2007-02-26 2012-03-27 United States Thermoelectric Consortium (USTC) Method for conditioning a cooling loop of a heat exchange system
US20110226495A1 (en) * 2008-09-15 2011-09-22 Fire Protection Systems Corrosion Management, Inc. High nitrogen and other inert gas anti-corrosion protection in wet pipe fire protection system
US20100263882A1 (en) * 2009-04-16 2010-10-21 South-Tek Systems System and method for fire protection system corrosion mitigation
WO2011056580A2 (fr) * 2009-10-27 2011-05-12 Fire Protection Systems Corrosion Management, Inc. Conduit d'évacuation de gaz de décharge commandé et procédé pour la réduction de la corrosion dans un système d'extincteur automatique de protection contre le feu sec
US20140048290A1 (en) * 2012-08-20 2014-02-20 South-Tek Systems, LLC Deoxygenated Water Fill for Fire Protection System

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2585178B1 (fr) * 2010-06-22 2023-08-23 Engineered Corrosion Solutions, LLC Haute protection anticorrosion à l'azote ou autre gaz inerte dans un système de protection contre l'incendie à canalisations humides

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