WO2012125175A1 - Field of the invention - Google Patents

Field of the invention Download PDF

Info

Publication number
WO2012125175A1
WO2012125175A1 PCT/US2011/035175 US2011035175W WO2012125175A1 WO 2012125175 A1 WO2012125175 A1 WO 2012125175A1 US 2011035175 W US2011035175 W US 2011035175W WO 2012125175 A1 WO2012125175 A1 WO 2012125175A1
Authority
WO
WIPO (PCT)
Prior art keywords
filter
ballast water
flush
electrolytic cell
reducing agent
Prior art date
Application number
PCT/US2011/035175
Other languages
French (fr)
Inventor
William Burroughs
Rudolf Matousek
Original Assignee
Severn Trent De Nora, 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 Severn Trent De Nora, Llc filed Critical Severn Trent De Nora, Llc
Priority to JP2013505217A priority Critical patent/JP5593439B2/en
Priority to JP2011004837U priority patent/JP3171387U/en
Publication of WO2012125175A1 publication Critical patent/WO2012125175A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F9/00—Multistage treatment of water, waste water or sewage
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
    • C02F1/4672—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electrooxydation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/70—Treatment of water, waste water, or sewage by reduction
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/008—Originating from marine vessels, ships and boats, e.g. bilge water or ballast water
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2209/00—Controlling or monitoring parameters in water treatment
    • C02F2209/04—Oxidation reduction potential [ORP]

Definitions

  • the invention relates generally to ballast water treatment including, and more specifically, to the treatment of an inline filter for eliminating marine species and pathogenic bacteria.
  • Ballast water is used to balance the weight distribution in a marine vessel. Often ballast water is taken on at one port and transported to another where it is emptied into the new port. This common practice has an inherent danger. Discharging the ballast water taken aboard from a port in one location can be both harmful to the environment and dangerous to humans and animals in and around a port of the discharge location.
  • Ballast water may be salt water drawn from a salt water source, such as an ocean or a sea at which port the marine vessel is docked. As described herein, salt water serves as ballast water; however, fresh water may similarly serve as ballast water.
  • a filter may be placed onboard the vessel to filter the ballast water and remove debris and large organisms prior to pumping the ballast water into tanks where it is stored to properly balance a vessel for a voyage.
  • the filter may often retain a residual amount of ballast water because of the filter's location on the vessel, which may prevent draining. This residual ballast water could escape to the environment in the back flush the next time ballast water is loaded onto the vessel in a new port, potentially causing harm to the environment and danger to humans and animals in the new port. This may also potentially violate, for example, the International Maritime Organization's (IMO) standards described in Regulation D-2 of the International
  • One or more embodiments of the invention provide a system and method for treating water onboard a marine vessel. More particularly, the one or more embodiments are directed to the treatment of ballast water and an inline water filter used onboard the marine vessel so that the ballast water, the filter, and any residual volume of water retained in the filter is decontaminated. Systems and methods of the invention kill the marine organisms that could inhabit/thrive in the filter and the filter discharge piping/valves and discharge flush flow effluent.
  • One aspect of the present invention is a ship-board system for in situ water treatment, the system comprising an inline filter contained within housing for filtration of incoming seawater; a ballast water and filter treatment system capable of decontaminating a flush flow discharged from the filter; and a flush line.
  • the flush flow may comprise a residual volume of seawater retained in the filter after the filtration.
  • the ballast water and filter treatment system may comprise an electrolytic cell for electrolyzing the filtered seawater to produce a depleted seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter; one or more ballast tanks in communication with the filter and the electrolytic cell, the ballast tanks receiving filtered seawater and/or the electrolyzed solution from the electrolytic cell; means for flushing the filter; and a neutralization system for neutralizing residual oxidants in the flush flow to less than 0.2 mg/L.
  • the flush line may have an inlet and an outlet.
  • the inlet of the flush line may abut the filter outlet.
  • the neutralized flush flow may be discharged through the flush line outlet.
  • the ballast water and filter treatment system may be further capable of decontaminating the flush line.
  • the means for flushing the filter may be a side stream of the electrolyzed solution from the electrolytic cell.
  • the means for flushing the filter may be a side stream of the filtered and treated seawater from the one or more ballast tanks.
  • the ship-board system for in situ water treatment may further have a means for measuring a concentration of the one or more oxidants in the flush flow, and a means for regulating a flow rate of the electrolyzed solution from the electrolytic cell in dependence on the measured concentration.
  • the means for measuring the concentration of the one or more oxidants may comprise one or more oxidation/reduction potential (ORP) analyzers capable of determining the ORP value of the flush flow.
  • ORP oxidation/reduction potential
  • the neutralization system may further comprise a reducing agent source in communication with the flush flow, and a means for controlling the amount of reducing agent supplied to the flush flow.
  • the reducing agent source may be one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
  • the neutralization system may have a tank for storing the reducing agent, and a neutralizer line in communication with the flush line.
  • a cyclone may be used for separating the hydrogen from the electrolyzed solution, diluting the separated hydrogen with ambient air and venting to the atmosphere.
  • Another aspect of the present invention is a method for in situ ballast water treatment onboard a marine vessel.
  • the method involves providing a self-cleaning filter for filtration of incoming seawater and installing a ballast water and filter treatment system onboard the vessel for decontaminating a flush flow discharged from the filter.
  • the flush flow may comprise a residual volume of water retained in the filter after filtration.
  • the ballast water and filter treatment system may comprise an electrolytic cell for electrolyzing the filtered seawater to produce a depleted seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter; and one or more ballast water tanks in communication with the filter and the electrolytic cell, the one or more ballast tanks receiving the filtered seawater and/or the electrolyzed solution from the electrolytic cell.
  • the method may further involve supplying means for flushing the filter.
  • the means for flushing the filter may comprise a side stream of the electrolyzed solution from the electrolytic cell.
  • the means for flushing the filter may comprise a side stream of filtered and treated seawater from the one or more ballast tanks.
  • Residual oxidants in the flush flow may be neutralized to less than 0.2 mg/L, and the neutralized flush flow may be discharged through a flush line.
  • the ballast water and filter treatment system may be further capable of decontaminating the flush line.
  • the neutralization of residual oxidants may involve providing a neutralization system having a reducing agent source in fluid communication with the flush flow.
  • the neutralization system may further comprise a means for controlling the amount of reducing agent supplied to the flush flow, a tank for storing the reducing agent, and a neutralizer line in communication with the flush line.
  • the reducing agent source may be one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
  • ORP analyzers may further determine the ORP value of the flush flow.
  • Hydrogen may be separated from the electrolyzed solution.
  • the separated hydrogen may be diluted with ambient air and vented to the atmosphere.
  • FIG. 1 shows a schematic illustrating a system for in situ treatment of ballast water and an inline filter according to one embodiment of the invention.
  • FIG. 2 shows a schematic illustrating a method for in situ treatment of ballast water and an inline filter according to one embodiment of the invention.
  • FIG. 1 illustrates one embodiment of a system 100 used onboard a marine vessel (not shown), for example a ship, for in situ treatment of ballast water and an inline filter.
  • An inline filter 108 may be used to filter ballast water.
  • a filter pump 104 draws ballast water from one or more sea chests or inlets to the filter 108.
  • the pump 104 is positioned upstream from the filter 108.
  • the ballast water may comprise seawater with natural salt content or fresh water.
  • the water may be pre-filtered by allowing it to flow through a coarse-mesh strainer (not shown).
  • the filter 108 may comprise at least one self-cleaning filter.
  • the filter 108 may comprise a strainer and a filter.
  • the water flows into the filter 108 through a water inlet 112.
  • the filter 108 may be placed within a housing (not shown).
  • the housing may be constructed of carbon steel, rubber-lined carbon steel, alloys or any other material suitable for housing the filter.
  • Water in the filter 108 flows through a filter screen having a filtration grade ranging from about 20 microns to about 5 millimeters.
  • the filter screen separates particulate matter (organic and inorganic) in the water to produce a dischargeable filtrate.
  • a small quantity or residual volume of water is inevitably retained in or entrapped within the filter 108.
  • This residual volume of water may be contaminated with marine organisms and bacteria that are potentially harmful to the environment. It is, therefore, important to decontaminate the residual water in the filter 108 to kill or destroy these entrapped organisms and bacteria, and eliminate the introduction of these non-native marine species and pathogenic bacteria into the water at a port other than the origination port.
  • the ballast water and filter treatment system 100 may further comprise a filter treatment system 102 having means for treating substantially all of the residual volume of water retained in the filter 108.
  • the term "residual volume of water” may include any contaminant contained within the residual volume of water in the filter 108 or any contaminant entrapped within the filter 108.
  • the ballast water and filter treatment system 100 may comprise one or more ballast tanks 120 to which a portion of the discharged filtrate flows via a main filtrate stream 118.
  • the main filtrate stream is also referred to as a "ballast water stream" herein.
  • the ballast water and filter treatment system 100 may further comprise one or more electrolytic cells 124 positioned downstream from the filter 108.
  • a side stream 128a of discharged filtrate may be separated from the main filtrate stream 118 and diverted to the one or more electrolytic cells 124.
  • a side stream 128c may be drawn from the one or more ballast tanks 120 after the main filtrate stream 118 has entered the one or more ballast tanks 120.
  • the side stream 128a flows through side stream piping to the one or more electrolytic cells 124 where hypochlorite is generated either from the salt naturally present in the ballast water, if seawater, or from added chloride salts if fresh water.
  • Seawater is used for the purposes of this description, but the embodiments of the present invention are not limited to seawater. Any chlorine- generating salt water may be used.
  • the electrolytic cells 124 may be equipped with electrodes energized under direct anodic and cathodic current. In this condition, partial electrolysis of sodium chloride (NaCl) contained in raw seawater occurs.
  • the aqueous solution of sodium chloride (NaCl) which is completely dissociated as sodium ion (Na + ) and chlorine ion (CI " ), reacts at the anode to generate free chlorine.
  • the hydroxide ions (OH ) in the water migrate from the cathodic area and react with Na + and Cl 2 near the anode to produce sodium hypochlorite (NaOCl) and hydrogen (H 2 ).
  • hypochlorous acid HOCl
  • HOBr hypobromous acid
  • the water can then flow into a cyclone hydrogen separator 125 where the hydrogen (H 2 ) byproduct of the hypochlorite generation is separated from a side stream 128b and vented into the atmosphere via hydrogen off-gas line 126.
  • the side stream 128b is then reintroduced to the main ballast water stream 118 to kill marine organisms and bacteria in the one or more ballast tanks 120.
  • the ballast water and filter treatment system 100 may comprise a total organic carbon (TOC) analyzer 129 in fluid communication with the ballast water 118.
  • a total organic carbon analyzer 129 is a device which measures the concentration of carbon in water from organic sources, such as microorganisms, plant materials, algae, organic acids, and mineral compounds of organic origin. As a general rule, it is known in the art that about 1 ppm of chlorine is required to neutralize about 1 ppm of TOC.
  • the ballast water and filter treatment system 100 may further comprise a means for controlling hypochlorite generation in communication with the total organic carbon analyzer 129.
  • the means for controlling hypochlorite generation can comprise any suitable equipment, in one embodiment it comprises a control system 130 in communication with the total organic carbon analyzer 129 and a power source 131 that is electrically connected to the electrolytic cells 124.
  • the control system 130 can adjust the amperage applied to the electrolytic cells 124 in response to the TOC measurement.
  • the ballast water and filter treatment system 100 may further comprise a flow meter 133 in fluid communication with the ballast water 118.
  • the flow meter 133 is in communication with the means for controlling hypochlorite generation.
  • the flow meter 133 can be placed in the ballast water stream 118 to measure the ballast water flow rate.
  • the means for controlling hypochlorite generation can utilize the ballast water flow rate and the TOC measurement to determine the amount of hypochlorite required to be generated to kill the organisms in the ballast water stream 118 and thus the amperage that must be applied to the electrolytic cells 124 to generate the hypochlorite.
  • the ballast water and filter treatment system 100 may further comprise one or more oxidation/reduction potential (ORP) probes 134.
  • ORP oxidation/reduction potential
  • an ORP probe 134 measures voltage across a circuit formed by a reference electrode and a measurement electrode, with the ballast water between the electrodes.
  • the ORP value of the ballast water 118 is relative to the concentration of the HOC1 and HOBr oxidizing agents in the ballast water 118. Both HOC1 and HOBr are oxidizing agent forms of halogens chlorine and bromine.
  • the ORP probe 134 is in fluid communication with the ballast water 118.
  • the ORP probe 134 communicates the ORP value to the means for controlling hypochlorite generation.
  • the means for controlling hypochlorite generation can use the measurement to confirm the existence of excess halogen in the form of an oxidizing agent in the ballast water 118 to ensure that enough hypochlorite is present to kill all microorganisms in the ballast water.
  • the ORP probe 134 is placed at one or more sites selected from a group consisting of: upstream of the ballast tanks 134, within the ballast tanks 120, downstream from the ballast tanks 122, downstream from the ballast water discharge pumps (not shown), a means for flushing 132 (ORP probe 197), a flush line 184 (ORP probe 198), and a neutralizer line 156 (ORP probe 199).
  • the ballast water and filter treatment system 100 may further comprise a means for recording system data 135.
  • the means for recording system data 135 can comprise any data recording equipment known in the art. Examples of such data recording equipment include computerized equipment, namely, a programmable logic controller (PLC), such as hard drives, flash memory, CD-ROMs, and magnetic disks, as well as non-computerized recording equipment, such as paper plots.
  • PLC programmable logic controller
  • System data to be measured and recorded can include any parameters desirable to one skilled in the art, including, but not limited to, ballast water flow rate, amperage applied to the electrolytic cells 124, voltage in the electrolytic cells 124, oxidation/reduction potential (ORP) value of the ballast water 118 and side stream 128 combined, and ORP value of the ballast water prior to discharge from the vessel.
  • the system data may be measured and recorded at timed intervals.
  • the ballast water and filter treatment system 100 may further comprise a means for verifying the effectiveness 137 of the ballast water treatment.
  • the means for verifying the effectiveness 137 of the ballast water treatment can be included within the means for recording system data or the means for controlling hypochlorite generation.
  • the means for verifying the effectiveness 137 of the ballast water treatment can comprise any means known in the art to demonstrate to a regulatory authority, such as the Coast Guard or Port Authority, that ballast water treatment was properly performed, including but not limited to, a plot of system data, a removable hard drive or flash drive, downloading system data on a laptop computer or a handheld device, transferring system data over the internet, or wirelessly transmitting system data to an off vessel location.
  • a regulatory authority such as the Coast Guard or Port Authority
  • the regulatory authority may use this information to confirm that the ballast water was properly treated.
  • the ballast water and filter treatment system 100 may further comprise a means for flushing the filter 132.
  • the means for flushing the filter 132 may allow the flow of a decontaminant, such as hypochlorite, to the filter 108 for decontaminating a flush flow discharged from the filter, the flush flow comprising a residual volume of seawater retained in the filter 108 after filtration.
  • the filter 108 further comprises a means for flushing inlet 136 to which a first end 140 of the means for flushing 132 is connected.
  • a second end 144 of the means for flushing 132 may be connected to a hypochlorite source comprising a receptacle containing hypochlorite.
  • the means for flushing 132 may comprise a side stream of the electrolyzed solution from the electrolytic cells 124.
  • the means for flushing 132 may comprise a side stream of the filtered and treated seawater from the ballast tanks 120.
  • Halogens in the form of halogen-containing oxidizing agents such as HOC1 and HOBr, are produced by hypochlorite generation and intended to kill organisms in the ballast water.
  • the halogen-containing oxidizing agents may be potentially dangerous to the marine flora and fauna around the vessel.
  • the ballast water and filter treatment system 100 may comprise a neutralization system 148 positioned downstream from the one or more ballast tanks 120.
  • Neutralizing the ballast water comprises neutralizing the oxidizing agents to form the neutral salts of the halogens.
  • the neutralization system 148 comprises a means for measuring 138 the oxidant content of the ballast water, a reducing agent source 139 in fluid communication with the ballast water via reducing agent piping 152, and a means for controlling 141 the amount of reducing agent supplied to the ballast water.
  • the means for controlling 141 the amount of reducing agent is in communication with the means for measuring 138 the halogen or reducing agent content.
  • the means for measuring 138 halogen or reducing agent content can comprise one or more oxidation/reduction potential (ORP) probes.
  • the means for controlling 141 the amount of reducing agent can comprise any combination of equipment known in the art, including, but not limited to, a control system, a computer, a programmable logic controller, and a pump.
  • the reducing agent source 139 can comprise a reducing agent tank and a pump in fluid communication with the reducing agent tank.
  • the pump is in communication with the means for controlling 141 the amount of reducing agent.
  • the reducing agent source 139 can further comprise any combination of suitable reducing agents. Examples of suitable reducing agents include sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
  • the neutralization system 148 may further comprise a means for verifying the effectiveness 142 of the neutralization 148 of the ballast water.
  • the means for verifying the effectiveness 142 of the neutralization 148 of the ballast water can comprise any means known in the art to demonstrate that the ballast water treatment was properly neutralized, including, but not limited to, a plot of system data, a removable hard drive or flash drive, downloading system data on a laptop computer or a handheld device, transferring system data over the internet, or wirelessly transmitting system data to an off vessel location.
  • the means for verifying the effectiveness 142 of the neutralization can be included in the means for controlling 141 the amount of reducing agent. A regulatory authority can use this data to confirm that the ballast water was properly neutralized.
  • the ballast water and filter treatment system 100 may further comprise a means for discharging the ballast water from the ballast tanks 120.
  • Discharge piping 122 defines a discharge opening to outside the vessel from which the ballast water is discharged 196.
  • the ballast water and filter treatment system 100 may further comprise a neutralizer line 156.
  • the neutralizer line 156 may allow the injection of a neutralizer to the hypochlorite- treated (or otherwise decontaminated) water to neutralize the residual chlorine and/or other oxidants present in the residual volume of water.
  • the residual chlorine may be neutralized to less than 0.2 mg/L.
  • the neutralizer line 156 may be connected to a reducing agent source at a first end 168.
  • a receptacle containing a reducing agent may serve as the source of a neutralizer and be connected to the neutralizer line 156 at the first end 168.
  • the reducing agent source 139 of the neutralization system 148 may supply a reducing agent through the neutralizer line 156 to the hypochlorite-treated water.
  • a second end 172 of the neutralizer line 156 may be connected to the filter 108.
  • the filter 108 may further comprise a neutralizer inlet 176 to which the second end 172 of the neutralizer line 156 may be attached.
  • the source of the reducing agent may be in fluid communication with the residual volume of water.
  • the filter 108 may further comprise a flush outlet 180 and a flush line 184 for backflushing/discharging the residual volume of water.
  • a first end 188 of the flush line 184 is attached to the flush outlet 180.
  • the neutralized flush flow may be discharged from the filter 108, with the decontaminated water exiting the flush outlet 180 and flowing away from the filter 108 via the flush line 184.
  • the second end 172 of the neutralizer line 156 may be connected to the flush line 184, establishing fluid communication between the reducing agent source and the flush flow to neutralize the residual oxidants present in the flush flow.
  • the neutralized water exits the flush line 184 at a second end 192 of the flush line 184 and is discharged 196 from the vessel.
  • ballast water is pumped 204 through a filter 208.
  • the filter may be capable of separating particulate matter from seawater or fresh water to produce a filtrate.
  • the filter discharges filtrate while retaining a residual volume of water within the filter.
  • the method further involves decontaminating the residual volume of water retained in the filter by subjecting the filter to one or more treatment processes.
  • the method may further comprise removing a portion of the filtrate to form a treatment stream 212 and piping the treatment stream to one or more electrolytic cells. Upon applying a current to the one or more electrolytic cells, the one or more electrolytic cells generate hypochlorite within the treatment stream 216. Hydrogen may be separated from the treatment stream by a means for venting.
  • the method may further comprise treating the residual volume of water retained in the filter to destroy or inactivate marine organisms and/or bacteria entrapped within the filter 220.
  • Fluid communication may be established between the filter and the electrolytic cells.
  • Hypochlorite generated by the one or more electrolytic cells may be used to treat the residual volume of water retained in the filter 220 by introducing one or more oxidants to the residual volume of water.
  • the hypochlorite generated by the one or more electrolytic cells 216 may be used to treat ballast water.
  • a portion of the filtrate discharged from the filter forms a ballast water stream.
  • the ballast water stream is piped as ballast water to the one or more ballast tanks and is sampled after the treatment stream is reintroduced into the ballast water to determine the oxidation/reduction potential (ORP) value of the ballast water stream.
  • the ORP value of the ballast water stream is measured by one or more ORP probes.
  • the current in the electrolytic cells is adjusted in response to the measured ORP value to increase or decrease the hypochlorite generated in the treatment stream to achieve the proper concentration of hypochlorite in the ballast water tank.
  • Treating the ballast water may further comprise ascertaining the total organic carbon content (TOC) of the ballast water.
  • TOC total organic carbon content
  • the oxidant demand can be ascertained in any suitable manner including measuring with a TOC analyzer, obtaining a value from a reference source, and sampling the ballast water and measuring TOC content with analytical equipment.
  • a measurement or sample can be taken at any suitable location, including in the incoming ballast water, the water outside the vessel, and the water in the ballast tanks.
  • the treatment stream is piped to the electrolytic cells.
  • the treatment stream may be a side stream of the filtrate piped as ballast water to one or more ballast tanks.
  • An amperage is applied to the one or more electrolytic cells to produce the hypochlorite within the treatment stream.
  • the treatment stream comprising hypochlorite is introduced to the ballast water to treat the ballast water.
  • the hypochlorite is introduced to the ballast water upstream of the ballast tanks to facilitate mixing of the hypochlorite and ballast water.
  • Hypochlorite production by the electrolytic cells is modulated in response to the oxidant demand of the ballast water. The higher the TOC content of the ballast water the greater the amount of hypochlorite that must be produced.
  • the step of modulating hypochlorite production by the electrolytic cells in response to the total organic carbon content may further comprise adjusting the amperage applied to the electrolytic cells. Increasing amperage results in increased hypochlorite production. Hypochlorite production may be modulated to maintain residual halogen in the ballast water. Residual halogen is halogen-containing oxidizing agent in excess of the amount required to kill all the microorganisms present in the ballast water. The presence of residual halogen in the ballast water ensures that no microorganisms remain in the ballast water can multiply in the ballast water tanks.
  • Hypochlorite production by the electrolytic cells may be modulated so that the weight ratio of the hypochlorite in the ballast water to oxidant demand in the ballast water ranges from about 1.0 to about 3.0.
  • a weight ratio greater than 1.0 should maintain residual halogen in the ballast water.
  • the flow rate of the ballast water may be measured.
  • the flow rate is combined with the TOC content of the ballast water to determine the hypochlorite generation rate required to treat the ballast water.
  • Process data may be measured and recorded.
  • Process data comprises one or more parameters selected from a group consisting of: ballast water flow rate, amperage applied to the electrolytic cells, voltage in the electrolytic cells, oxidation/reduction potential of the ballast water and side stream combined, and oxidation/reduction potential of the ballast water prior to discharge from the vessel.
  • hypochlorite generated in the electrolytic cells 216 may be used to treat the residual volume of water retained in the filter 220.
  • hypochlorite-treated ballast water may be used to treat the residual volume of water retained in the filter 220.
  • hypochlorite inside the one or more ballast tanks may be used to treat the residual volume of water retained in the filter 220.
  • Residual halogen in the ballast water produced by the electrolytic cells in response to the TOC content can be removed by neutralizing the ballast water prior to discharge from the vessel.
  • a reducing agent may be supplied to a neutralization system 224.
  • the reducing agent may be used to neutralize the oxidants in the hypochlorite-treated ballast water 228 prior to discharging the ballast water from the vessel 232.
  • Neutralizing the ballast water may comprise measuring the oxidant content of the ballast water with a means for measuring oxidant content.
  • a reducing agent is added to the ballast water in response to the measured oxidant content to neutralize the ballast water prior to discharge from the vessel.
  • the reducing agent may be added downstream from the ballast tank.
  • suitable reducing agents include sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, sodium thiosulfate, and combinations thereof.
  • Neutralizing the ballast water may further comprise measuring the oxidation/reduction potential (ORP) value of the ballast water.
  • ORP oxidation/reduction potential
  • One or more reducing agents are added to the ballast water to neutralize the ballast water in response to the measured ORP value.
  • the amount of reducing agent added to the ballast water can be modulated to maintain an ORP value measurement that indicates excess reducing agent is present in the ballast water. When excess reducing agent is present, potentially harmful halogens like chlorine and bromine should not be present.
  • the oxidation/reduction potential may be maintained at less than about 200 mV.
  • An ORP value of less than 200 mV indicates that excess reducing agent exists. In another aspect, the oxidation/reduction potential is maintained at about 0 mV.
  • the reducing agent may be introduced within the filter to neutralize the one or more oxidizing agents or residual chlorine in the residual volume of water.
  • Neutralizing the residual chlorine may comprise adding one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, sodium thiosulfate, and combinations thereof, to the one or more oxidizing agents.
  • a flush line transports a flush flow comprising the decontaminated residual volume of water from the filter to a discharge area 232.
  • the reducing agent may be introduced to the hypochlorite-treated water at some point of the flush line prior to discharge.
  • Means for measuring, controlling and recording system and process data such as a total carbon analyzer, a means for controlling hypochlorite generation, a flow meter, an oxidation/reduction potential (ORP) probe, a means for recording system data, described above may also be used to measure, control, and record system and process parameters in connection with decontaminating and neutralizing the residual volume retained in the filter.
  • a total carbon analyzer such as a total carbon analyzer, a means for controlling hypochlorite generation, a flow meter, an oxidation/reduction potential (ORP) probe, a means for recording system data, described above may also be used to measure, control, and record system and process parameters in connection with decontaminating and neutralizing the residual volume retained in the filter.
  • ORP oxidation/reduction potential
  • inventions comprise systems and methods for killing marine organisms that inhabit/thrive in the filter and the filter discharge piping/valves and discharging flush flow effluent via blowdown/draining, fresh water rinsing, treating with chlorine, treating with ozone, treating with peroxide, treating with phosphate, treating with any other suitable chemical, nitrogen purging, carbon dioxide purging, oxygen stripping/vacuum induced oxygen depleting, hot water soaking (salt water and/or fresh water), steaming, and combinations thereof.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)
  • Treatment Of Water By Oxidation Or Reduction (AREA)
  • Physical Water Treatments (AREA)

Abstract

Methods and systems are provided for decontaminating inline water filters used onboard a marine vessel.

Description

METHOD AND SYSTEM FOR BALLAST WATER AND FILTER TREATMENT
FIELD OF THE INVENTION
[0001] The invention relates generally to ballast water treatment including, and more specifically, to the treatment of an inline filter for eliminating marine species and pathogenic bacteria. BACKGROUND
[0002] Ballast water is used to balance the weight distribution in a marine vessel. Often ballast water is taken on at one port and transported to another where it is emptied into the new port. This common practice has an inherent danger. Discharging the ballast water taken aboard from a port in one location can be both harmful to the environment and dangerous to humans and animals in and around a port of the discharge location. Ballast water may be salt water drawn from a salt water source, such as an ocean or a sea at which port the marine vessel is docked. As described herein, salt water serves as ballast water; however, fresh water may similarly serve as ballast water. [0003] A filter may be placed onboard the vessel to filter the ballast water and remove debris and large organisms prior to pumping the ballast water into tanks where it is stored to properly balance a vessel for a voyage. The filter may often retain a residual amount of ballast water because of the filter's location on the vessel, which may prevent draining. This residual ballast water could escape to the environment in the back flush the next time ballast water is loaded onto the vessel in a new port, potentially causing harm to the environment and danger to humans and animals in the new port. This may also potentially violate, for example, the International Maritime Organization's (IMO) standards described in Regulation D-2 of the International
RECTIFIED SHEET (RULE 91)
l Convention for the Control and Management of Ships' Ballast Water and Sediments, United States Coast Guard (USCG) guidelines, and ballast water treatment performance standards of various states of the United States.
[0004] The introduction of non-native marine life into a new ecosystem can have a devastating effect on the native flora and fauna which may not have natural defenses to the new species. Additionally, harmful bacterial pathogens, such as cholera, may be present in the origination port. These pathogens can multiply in the ballast tanks and in the filter over time and cause an outbreak of illness in the area where they are released.
SUMMARY
[0005] One or more embodiments of the invention provide a system and method for treating water onboard a marine vessel. More particularly, the one or more embodiments are directed to the treatment of ballast water and an inline water filter used onboard the marine vessel so that the ballast water, the filter, and any residual volume of water retained in the filter is decontaminated. Systems and methods of the invention kill the marine organisms that could inhabit/thrive in the filter and the filter discharge piping/valves and discharge flush flow effluent.
[0006] One aspect of the present invention is a ship-board system for in situ water treatment, the system comprising an inline filter contained within housing for filtration of incoming seawater; a ballast water and filter treatment system capable of decontaminating a flush flow discharged from the filter; and a flush line. The flush flow may comprise a residual volume of seawater retained in the filter after the filtration. [0007] The ballast water and filter treatment system may comprise an electrolytic cell for electrolyzing the filtered seawater to produce a depleted seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter; one or more ballast tanks in communication with the filter and the electrolytic cell, the ballast tanks receiving filtered seawater and/or the electrolyzed solution from the electrolytic cell; means for flushing the filter; and a neutralization system for neutralizing residual oxidants in the flush flow to less than 0.2 mg/L.
[0008] The flush line may have an inlet and an outlet. The inlet of the flush line may abut the filter outlet. The neutralized flush flow may be discharged through the flush line outlet. The ballast water and filter treatment system may be further capable of decontaminating the flush line.
[0009] The means for flushing the filter may be a side stream of the electrolyzed solution from the electrolytic cell. Alternatively, the means for flushing the filter may be a side stream of the filtered and treated seawater from the one or more ballast tanks.
[0010] The ship-board system for in situ water treatment may further have a means for measuring a concentration of the one or more oxidants in the flush flow, and a means for regulating a flow rate of the electrolyzed solution from the electrolytic cell in dependence on the measured concentration. The means for measuring the concentration of the one or more oxidants may comprise one or more oxidation/reduction potential (ORP) analyzers capable of determining the ORP value of the flush flow.
[0011] The neutralization system may further comprise a reducing agent source in communication with the flush flow, and a means for controlling the amount of reducing agent supplied to the flush flow. The reducing agent source may be one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate. Moreover, the neutralization system may have a tank for storing the reducing agent, and a neutralizer line in communication with the flush line.
[0012] A cyclone may be used for separating the hydrogen from the electrolyzed solution, diluting the separated hydrogen with ambient air and venting to the atmosphere.
[0013] Another aspect of the present invention is a method for in situ ballast water treatment onboard a marine vessel. The method involves providing a self-cleaning filter for filtration of incoming seawater and installing a ballast water and filter treatment system onboard the vessel for decontaminating a flush flow discharged from the filter. The flush flow may comprise a residual volume of water retained in the filter after filtration.
[0014] The ballast water and filter treatment system may comprise an electrolytic cell for electrolyzing the filtered seawater to produce a depleted seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter; and one or more ballast water tanks in communication with the filter and the electrolytic cell, the one or more ballast tanks receiving the filtered seawater and/or the electrolyzed solution from the electrolytic cell.
[0015] The method may further involve supplying means for flushing the filter. The means for flushing the filter may comprise a side stream of the electrolyzed solution from the electrolytic cell. Alternatively, the means for flushing the filter may comprise a side stream of filtered and treated seawater from the one or more ballast tanks. [0016] Residual oxidants in the flush flow may be neutralized to less than 0.2 mg/L, and the neutralized flush flow may be discharged through a flush line. The ballast water and filter treatment system may be further capable of decontaminating the flush line. The neutralization of residual oxidants may involve providing a neutralization system having a reducing agent source in fluid communication with the flush flow. The neutralization system may further comprise a means for controlling the amount of reducing agent supplied to the flush flow, a tank for storing the reducing agent, and a neutralizer line in communication with the flush line. The reducing agent source may be one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
[0017] The method may further involve measuring a concentration of the one or more oxidants in the flush flow, and regulating a flow rate of the electrolyzed solution from the electrolytic cell in dependence on the measured concentration. Measuring the concentration of the one or more oxidants may involve providing one or more oxidation/reduction potential (ORP) analyzers. The ORP analyzers may further determine the ORP value of the flush flow.
[0018] Hydrogen may be separated from the electrolyzed solution. The separated hydrogen may be diluted with ambient air and vented to the atmosphere.
[0019] Various objects, features, aspects, and advantages of the present invention will become more apparent from the following detailed description of embodiments of the invention, along with the accompanying drawings in which like numerals represent like components. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows a schematic illustrating a system for in situ treatment of ballast water and an inline filter according to one embodiment of the invention.
[0021] FIG. 2 shows a schematic illustrating a method for in situ treatment of ballast water and an inline filter according to one embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0022] FIG. 1 illustrates one embodiment of a system 100 used onboard a marine vessel (not shown), for example a ship, for in situ treatment of ballast water and an inline filter. An inline filter 108 may be used to filter ballast water. A filter pump 104 draws ballast water from one or more sea chests or inlets to the filter 108. The pump 104 is positioned upstream from the filter 108. The ballast water may comprise seawater with natural salt content or fresh water.
[0023] The water may be pre-filtered by allowing it to flow through a coarse-mesh strainer (not shown). The filter 108 may comprise at least one self-cleaning filter. In another embodiment, the filter 108 may comprise a strainer and a filter. The water flows into the filter 108 through a water inlet 112. The filter 108 may be placed within a housing (not shown). The housing may be constructed of carbon steel, rubber-lined carbon steel, alloys or any other material suitable for housing the filter. Water in the filter 108 flows through a filter screen having a filtration grade ranging from about 20 microns to about 5 millimeters. The filter screen separates particulate matter (organic and inorganic) in the water to produce a dischargeable filtrate. The filtrate exits the filter 108 through a filtrate outlet 116. [0024] Although substantially all the water entering the filter 108 may be filtered out or discharged, a small quantity or residual volume of water is inevitably retained in or entrapped within the filter 108. This residual volume of water may be contaminated with marine organisms and bacteria that are potentially harmful to the environment. It is, therefore, important to decontaminate the residual water in the filter 108 to kill or destroy these entrapped organisms and bacteria, and eliminate the introduction of these non-native marine species and pathogenic bacteria into the water at a port other than the origination port.
[0025] The ballast water and filter treatment system 100 may further comprise a filter treatment system 102 having means for treating substantially all of the residual volume of water retained in the filter 108. As used herein, the term "residual volume of water" may include any contaminant contained within the residual volume of water in the filter 108 or any contaminant entrapped within the filter 108.
[0026] The ballast water and filter treatment system 100 may comprise one or more ballast tanks 120 to which a portion of the discharged filtrate flows via a main filtrate stream 118. The main filtrate stream is also referred to as a "ballast water stream" herein. The ballast water and filter treatment system 100 may further comprise one or more electrolytic cells 124 positioned downstream from the filter 108. A side stream 128a of discharged filtrate may be separated from the main filtrate stream 118 and diverted to the one or more electrolytic cells 124. In an alternative embodiment, a side stream 128c may be drawn from the one or more ballast tanks 120 after the main filtrate stream 118 has entered the one or more ballast tanks 120.
[0027] The side stream 128a flows through side stream piping to the one or more electrolytic cells 124 where hypochlorite is generated either from the salt naturally present in the ballast water, if seawater, or from added chloride salts if fresh water. Seawater is used for the purposes of this description, but the embodiments of the present invention are not limited to seawater. Any chlorine- generating salt water may be used.
[0028] The electrolytic cells 124 may be equipped with electrodes energized under direct anodic and cathodic current. In this condition, partial electrolysis of sodium chloride (NaCl) contained in raw seawater occurs. The aqueous solution of sodium chloride (NaCl), which is completely dissociated as sodium ion (Na+) and chlorine ion (CI"), reacts at the anode to generate free chlorine. The hydroxide ions (OH ) in the water migrate from the cathodic area and react with Na+ and Cl2 near the anode to produce sodium hypochlorite (NaOCl) and hydrogen (H2).
[0029] Sodium hypochlorite in water hydrolizes to form hypochlorous acid (HOCl). Some of the HOCl reacts with the bromine in the water to form hypobromous acid (HOBr). HOCl and HOBr act as the killing agents used to treat the ballast water.
[0030] The water can then flow into a cyclone hydrogen separator 125 where the hydrogen (H2) byproduct of the hypochlorite generation is separated from a side stream 128b and vented into the atmosphere via hydrogen off-gas line 126. The side stream 128b is then reintroduced to the main ballast water stream 118 to kill marine organisms and bacteria in the one or more ballast tanks 120.
[0031] The ballast water and filter treatment system 100 may comprise a total organic carbon (TOC) analyzer 129 in fluid communication with the ballast water 118. A total organic carbon analyzer 129 is a device which measures the concentration of carbon in water from organic sources, such as microorganisms, plant materials, algae, organic acids, and mineral compounds of organic origin. As a general rule, it is known in the art that about 1 ppm of chlorine is required to neutralize about 1 ppm of TOC.
[0032] The ballast water and filter treatment system 100 may further comprise a means for controlling hypochlorite generation in communication with the total organic carbon analyzer 129. While the means for controlling hypochlorite generation can comprise any suitable equipment, in one embodiment it comprises a control system 130 in communication with the total organic carbon analyzer 129 and a power source 131 that is electrically connected to the electrolytic cells 124. The control system 130 can adjust the amperage applied to the electrolytic cells 124 in response to the TOC measurement.
[0033] The ballast water and filter treatment system 100 may further comprise a flow meter 133 in fluid communication with the ballast water 118. The flow meter 133 is in communication with the means for controlling hypochlorite generation. The flow meter 133 can be placed in the ballast water stream 118 to measure the ballast water flow rate. The means for controlling hypochlorite generation can utilize the ballast water flow rate and the TOC measurement to determine the amount of hypochlorite required to be generated to kill the organisms in the ballast water stream 118 and thus the amperage that must be applied to the electrolytic cells 124 to generate the hypochlorite.
[0034] The ballast water and filter treatment system 100 may further comprise one or more oxidation/reduction potential (ORP) probes 134. In general, an ORP probe 134 measures voltage across a circuit formed by a reference electrode and a measurement electrode, with the ballast water between the electrodes. The ORP value of the ballast water 118 is relative to the concentration of the HOC1 and HOBr oxidizing agents in the ballast water 118. Both HOC1 and HOBr are oxidizing agent forms of halogens chlorine and bromine. The ORP probe 134 is in fluid communication with the ballast water 118. The ORP probe 134 communicates the ORP value to the means for controlling hypochlorite generation. When the ORP probe 134 is placed downstream from the point of addition 127 of the hypochlorite to the ballast water 118, the means for controlling hypochlorite generation can use the measurement to confirm the existence of excess halogen in the form of an oxidizing agent in the ballast water 118 to ensure that enough hypochlorite is present to kill all microorganisms in the ballast water. In varying embodiments, the ORP probe 134 is placed at one or more sites selected from a group consisting of: upstream of the ballast tanks 134, within the ballast tanks 120, downstream from the ballast tanks 122, downstream from the ballast water discharge pumps (not shown), a means for flushing 132 (ORP probe 197), a flush line 184 (ORP probe 198), and a neutralizer line 156 (ORP probe 199).
[0035] The ballast water and filter treatment system 100 may further comprise a means for recording system data 135. The means for recording system data 135 can comprise any data recording equipment known in the art. Examples of such data recording equipment include computerized equipment, namely, a programmable logic controller (PLC), such as hard drives, flash memory, CD-ROMs, and magnetic disks, as well as non-computerized recording equipment, such as paper plots. System data to be measured and recorded can include any parameters desirable to one skilled in the art, including, but not limited to, ballast water flow rate, amperage applied to the electrolytic cells 124, voltage in the electrolytic cells 124, oxidation/reduction potential (ORP) value of the ballast water 118 and side stream 128 combined, and ORP value of the ballast water prior to discharge from the vessel. The system data may be measured and recorded at timed intervals. [0036] The ballast water and filter treatment system 100 may further comprise a means for verifying the effectiveness 137 of the ballast water treatment. The means for verifying the effectiveness 137 of the ballast water treatment can be included within the means for recording system data or the means for controlling hypochlorite generation. The means for verifying the effectiveness 137 of the ballast water treatment can comprise any means known in the art to demonstrate to a regulatory authority, such as the Coast Guard or Port Authority, that ballast water treatment was properly performed, including but not limited to, a plot of system data, a removable hard drive or flash drive, downloading system data on a laptop computer or a handheld device, transferring system data over the internet, or wirelessly transmitting system data to an off vessel location. The regulatory authority may use this information to confirm that the ballast water was properly treated.
[0037] The ballast water and filter treatment system 100 may further comprise a means for flushing the filter 132. The means for flushing the filter 132 may allow the flow of a decontaminant, such as hypochlorite, to the filter 108 for decontaminating a flush flow discharged from the filter, the flush flow comprising a residual volume of seawater retained in the filter 108 after filtration. The filter 108 further comprises a means for flushing inlet 136 to which a first end 140 of the means for flushing 132 is connected. In one embodiment, a second end 144 of the means for flushing 132 may be connected to a hypochlorite source comprising a receptacle containing hypochlorite. For example, the means for flushing 132 may comprise a side stream of the electrolyzed solution from the electrolytic cells 124. In another embodiment, the means for flushing 132 may comprise a side stream of the filtered and treated seawater from the ballast tanks 120. [0038] Halogens in the form of halogen-containing oxidizing agents, such as HOC1 and HOBr, are produced by hypochlorite generation and intended to kill organisms in the ballast water. However, the halogen-containing oxidizing agents may be potentially dangerous to the marine flora and fauna around the vessel.
[0039] In one embodiment of the system of the invention, the ballast water and filter treatment system 100 may comprise a neutralization system 148 positioned downstream from the one or more ballast tanks 120. Neutralizing the ballast water comprises neutralizing the oxidizing agents to form the neutral salts of the halogens. The neutralization system 148 comprises a means for measuring 138 the oxidant content of the ballast water, a reducing agent source 139 in fluid communication with the ballast water via reducing agent piping 152, and a means for controlling 141 the amount of reducing agent supplied to the ballast water. The means for controlling 141 the amount of reducing agent is in communication with the means for measuring 138 the halogen or reducing agent content.
[0040] The means for measuring 138 halogen or reducing agent content can comprise one or more oxidation/reduction potential (ORP) probes. The means for controlling 141 the amount of reducing agent can comprise any combination of equipment known in the art, including, but not limited to, a control system, a computer, a programmable logic controller, and a pump.
[0041] The reducing agent source 139 can comprise a reducing agent tank and a pump in fluid communication with the reducing agent tank. The pump is in communication with the means for controlling 141 the amount of reducing agent. The reducing agent source 139 can further comprise any combination of suitable reducing agents. Examples of suitable reducing agents include sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
[0042] The neutralization system 148 may further comprise a means for verifying the effectiveness 142 of the neutralization 148 of the ballast water. The means for verifying the effectiveness 142 of the neutralization 148 of the ballast water can comprise any means known in the art to demonstrate that the ballast water treatment was properly neutralized, including, but not limited to, a plot of system data, a removable hard drive or flash drive, downloading system data on a laptop computer or a handheld device, transferring system data over the internet, or wirelessly transmitting system data to an off vessel location. Optionally, the means for verifying the effectiveness 142 of the neutralization can be included in the means for controlling 141 the amount of reducing agent. A regulatory authority can use this data to confirm that the ballast water was properly neutralized.
[0043] The ballast water and filter treatment system 100 may further comprise a means for discharging the ballast water from the ballast tanks 120. Discharge piping 122 defines a discharge opening to outside the vessel from which the ballast water is discharged 196.
[0044] The ballast water and filter treatment system 100 may further comprise a neutralizer line 156. The neutralizer line 156 may allow the injection of a neutralizer to the hypochlorite- treated (or otherwise decontaminated) water to neutralize the residual chlorine and/or other oxidants present in the residual volume of water. The residual chlorine may be neutralized to less than 0.2 mg/L. The neutralizer line 156 may be connected to a reducing agent source at a first end 168. A receptacle containing a reducing agent may serve as the source of a neutralizer and be connected to the neutralizer line 156 at the first end 168. For example, in one embodiment, the reducing agent source 139 of the neutralization system 148 may supply a reducing agent through the neutralizer line 156 to the hypochlorite-treated water.
[0045] A second end 172 of the neutralizer line 156 may be connected to the filter 108. The filter 108 may further comprise a neutralizer inlet 176 to which the second end 172 of the neutralizer line 156 may be attached. The source of the reducing agent may be in fluid communication with the residual volume of water.
[0046] The filter 108 may further comprise a flush outlet 180 and a flush line 184 for backflushing/discharging the residual volume of water. A first end 188 of the flush line 184 is attached to the flush outlet 180. The neutralized flush flow may be discharged from the filter 108, with the decontaminated water exiting the flush outlet 180 and flowing away from the filter 108 via the flush line 184. In an alternative embodiment, the second end 172 of the neutralizer line 156 may be connected to the flush line 184, establishing fluid communication between the reducing agent source and the flush flow to neutralize the residual oxidants present in the flush flow. The neutralized water exits the flush line 184 at a second end 192 of the flush line 184 and is discharged 196 from the vessel.
[0047] Referring now to FIG. 2, in one or more embodiments of a method of the invention, ballast water is pumped 204 through a filter 208. As described earlier, the filter may be capable of separating particulate matter from seawater or fresh water to produce a filtrate. The filter discharges filtrate while retaining a residual volume of water within the filter. The method further involves decontaminating the residual volume of water retained in the filter by subjecting the filter to one or more treatment processes. [0048] The method may further comprise removing a portion of the filtrate to form a treatment stream 212 and piping the treatment stream to one or more electrolytic cells. Upon applying a current to the one or more electrolytic cells, the one or more electrolytic cells generate hypochlorite within the treatment stream 216. Hydrogen may be separated from the treatment stream by a means for venting.
[0049] The method may further comprise treating the residual volume of water retained in the filter to destroy or inactivate marine organisms and/or bacteria entrapped within the filter 220. Fluid communication may be established between the filter and the electrolytic cells. Hypochlorite generated by the one or more electrolytic cells may be used to treat the residual volume of water retained in the filter 220 by introducing one or more oxidants to the residual volume of water.
[0050] The hypochlorite generated by the one or more electrolytic cells 216 may be used to treat ballast water. In one aspect, a portion of the filtrate discharged from the filter forms a ballast water stream. The ballast water stream is piped as ballast water to the one or more ballast tanks and is sampled after the treatment stream is reintroduced into the ballast water to determine the oxidation/reduction potential (ORP) value of the ballast water stream. The ORP value of the ballast water stream is measured by one or more ORP probes. The current in the electrolytic cells is adjusted in response to the measured ORP value to increase or decrease the hypochlorite generated in the treatment stream to achieve the proper concentration of hypochlorite in the ballast water tank.
[0051] Treating the ballast water may further comprise ascertaining the total organic carbon content (TOC) of the ballast water. The oxidant demand can be ascertained in any suitable manner including measuring with a TOC analyzer, obtaining a value from a reference source, and sampling the ballast water and measuring TOC content with analytical equipment. When measuring the total organic carbon content of the ballast water, a measurement or sample can be taken at any suitable location, including in the incoming ballast water, the water outside the vessel, and the water in the ballast tanks.
[0052] To generate hypochlorite, the treatment stream is piped to the electrolytic cells. The treatment stream may be a side stream of the filtrate piped as ballast water to one or more ballast tanks. An amperage is applied to the one or more electrolytic cells to produce the hypochlorite within the treatment stream. The treatment stream comprising hypochlorite is introduced to the ballast water to treat the ballast water. In one embodiment, the hypochlorite is introduced to the ballast water upstream of the ballast tanks to facilitate mixing of the hypochlorite and ballast water. Hypochlorite production by the electrolytic cells is modulated in response to the oxidant demand of the ballast water. The higher the TOC content of the ballast water the greater the amount of hypochlorite that must be produced.
[0053] The step of modulating hypochlorite production by the electrolytic cells in response to the total organic carbon content may further comprise adjusting the amperage applied to the electrolytic cells. Increasing amperage results in increased hypochlorite production. Hypochlorite production may be modulated to maintain residual halogen in the ballast water. Residual halogen is halogen-containing oxidizing agent in excess of the amount required to kill all the microorganisms present in the ballast water. The presence of residual halogen in the ballast water ensures that no microorganisms remain in the ballast water can multiply in the ballast water tanks. Hypochlorite production by the electrolytic cells may be modulated so that the weight ratio of the hypochlorite in the ballast water to oxidant demand in the ballast water ranges from about 1.0 to about 3.0. A weight ratio greater than 1.0 should maintain residual halogen in the ballast water.
[0054] The flow rate of the ballast water may be measured. The flow rate is combined with the TOC content of the ballast water to determine the hypochlorite generation rate required to treat the ballast water.
[0055] Process data may be measured and recorded. Process data comprises one or more parameters selected from a group consisting of: ballast water flow rate, amperage applied to the electrolytic cells, voltage in the electrolytic cells, oxidation/reduction potential of the ballast water and side stream combined, and oxidation/reduction potential of the ballast water prior to discharge from the vessel.
[0056] In one embodiment, the hypochlorite generated in the electrolytic cells 216 may be used to treat the residual volume of water retained in the filter 220. In another embodiment, the hypochlorite-treated ballast water may be used to treat the residual volume of water retained in the filter 220. For example, hypochlorite inside the one or more ballast tanks may be used to treat the residual volume of water retained in the filter 220.
[0057] Residual halogen in the ballast water produced by the electrolytic cells in response to the TOC content can be removed by neutralizing the ballast water prior to discharge from the vessel.
[0058] A reducing agent may be supplied to a neutralization system 224. The reducing agent may be used to neutralize the oxidants in the hypochlorite-treated ballast water 228 prior to discharging the ballast water from the vessel 232. [0059] Neutralizing the ballast water may comprise measuring the oxidant content of the ballast water with a means for measuring oxidant content. A reducing agent is added to the ballast water in response to the measured oxidant content to neutralize the ballast water prior to discharge from the vessel. In one aspect, the reducing agent may be added downstream from the ballast tank. Examples of suitable reducing agents include sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, sodium thiosulfate, and combinations thereof.
[0060] Neutralizing the ballast water may further comprise measuring the oxidation/reduction potential (ORP) value of the ballast water. One or more reducing agents are added to the ballast water to neutralize the ballast water in response to the measured ORP value. The amount of reducing agent added to the ballast water can be modulated to maintain an ORP value measurement that indicates excess reducing agent is present in the ballast water. When excess reducing agent is present, potentially harmful halogens like chlorine and bromine should not be present. The oxidation/reduction potential may be maintained at less than about 200 mV. An ORP value of less than 200 mV indicates that excess reducing agent exists. In another aspect, the oxidation/reduction potential is maintained at about 0 mV.
[0061] In one embodiment, the reducing agent may be introduced within the filter to neutralize the one or more oxidizing agents or residual chlorine in the residual volume of water. Neutralizing the residual chlorine may comprise adding one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, sodium thiosulfate, and combinations thereof, to the one or more oxidizing agents. [0062] A flush line transports a flush flow comprising the decontaminated residual volume of water from the filter to a discharge area 232. In another embodiment, the reducing agent may be introduced to the hypochlorite-treated water at some point of the flush line prior to discharge.
[0063] Means for measuring, controlling and recording system and process data, such as a total carbon analyzer, a means for controlling hypochlorite generation, a flow meter, an oxidation/reduction potential (ORP) probe, a means for recording system data, described above may also be used to measure, control, and record system and process parameters in connection with decontaminating and neutralizing the residual volume retained in the filter.
[0064] Other embodiments of the invention comprise systems and methods for killing marine organisms that inhabit/thrive in the filter and the filter discharge piping/valves and discharging flush flow effluent via blowdown/draining, fresh water rinsing, treating with chlorine, treating with ozone, treating with peroxide, treating with phosphate, treating with any other suitable chemical, nitrogen purging, carbon dioxide purging, oxygen stripping/vacuum induced oxygen depleting, hot water soaking (salt water and/or fresh water), steaming, and combinations thereof.
[0065] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

Claims

CLAIMS We claim:
1. A ship-board system for in situ water treatment, the system comprising:
an inline filter contained within housing for filtration of incoming seawater;
a ballast water and filter treatment system capable of decontaminating a flush
flow discharged from the filter, the flush flow comprising a residual volume of seawater retained in the filter after the filtration,
the ballast water and filter treatment system comprising:
an electrolytic cell for electrolyzing the filtered seawater to produce a depleted
seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter;
one or more ballast water tanks in communication with the filter and the
electrolytic cell, the one or more ballast water tanks for receiving the filtered seawater and/or the electrolyzed solution from the electrolytic cell; means for flushing the filter; and
a neutralization system for neutralizing residual oxidants in the flush flow to
less than 0.2 mg/L, and
a flush line, the flush line having an inlet and an outlet, the flush line inlet
abutting a filter outlet, the neutralized flush flow discharged through the flush line outlet, the ballast water and filter treatment system further capable of decontaminating the flush line.
2. The system of claim 1, the means for flushing the filter comprising a side stream of the electrolyzed solution from the electrolytic cell.
3. The system of claim 1, the means for flushing the filter comprising a side stream of the filtered seawater and/or the electrolyzed solution from the one or more ballast water tanks.
4. The system of claim 2 further comprising: means for measuring a concentration of the one or more oxidants in the
flush flow; and
means for regulating a flow rate of the electrolyzed solution from the electrolytic
cell in dependence on the measured concentration.
5. The system of claim 4, wherein the means for measuring the concentration of the one or more oxidants comprises one or more oxidation/reduction potential analyzers, the one or more oxidation/reduction potential analyzers further determining the oxidation/reduction potential of the flush flow.
6. The system of claim 1, the neutralization system further comprising:
a reducing agent source in communication with the flush flow; and
means for controlling the amount of reducing agent supplied to the flush flow.
7. The system of claim 6, wherein the reducing agent source comprises one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
8. The system of claim 6, the neutralization system further comprising:
a tank for storing the reducing agent; and
a neutralizer line in communication with the flush line.
9. The system of claim 1, further comprising a cyclone for separating the hydrogen from the electrolyzed solution, the separated hydrogen diluted with ambient air and vented to the atmosphere.
10. A method for in situ ballast water treatment onboard a marine vessel, the method comprising:
providing a self-cleaning filter for filtration of incoming seawater;
installing a ballast water and filter treatment system onboard the vessel for decontaminating a flush flow discharged from the filter, the flush flow comprising a residual volume of seawater retained in the filter after the filtration, the ballast water and filter treatment system comprising:
an electrolytic cell for electrolyzing the filtered seawater to produce a depleted
seawater solution comprising one or more oxidants and hydrogen, the electrolytic cell in fluid communication with the filter;
one or more ballast water tanks in communication with the filter and the
electrolytic cell, the one or more ballast water tanks for receiving the filtered seawater and/or the electrolyzed solution from the electrolytic cell; supplying means for flushing the filter;
neutralizing residual oxidants in the flush flow to less than 0.2 mg/L, and
discharging the neutralized flush flow through a flush line, the ballast water and
filter treatment system further capable of decontaminating the flush line.
11. The method of claim 10, the means for flushing the filter comprising a side stream of the electrolyzed solution from the electrolytic cell.
12. The method of claim 10, the means for flushing the filter comprising a side stream of the filtered seawater and/or the electrolyzed solution from the one or more ballast water tanks.
13. The method of claim 11 further comprising:
measuring a concentration of the one or more oxidants in the flush flow; and regulating a flow rate of the electrolyzed solution from the electrolytic cell in dependence on the measured concentration.
14. The method of claim 13, the measuring the concentration of the one or more oxidants comprises providing one or more oxidation/reduction potential analyzers, the one or more oxidation/reduction potential analyzers further determining the
oxidation/reduction potential of the flush flow.
15. The method of claim 10, the neutralization of residual oxidants further comprising providing a neutralization system, the neutralization system further comprising:
a reducing agent source in communication with the flush flow;
means for controlling the amount of reducing agent supplied to the flush flow;
a tank for storing the reducing agent; and
a neutralizer line in communication with the flush line.
16. The method of claim 15, the reducing agent source comprises one or more reducing agents selected from a group consisting of sodium sulfite, sodium metabisulfite, sodium bisulfite, sulfur dioxide, and sodium thiosulfate.
17. The method of claim 10, further comprising separating the hydrogen from the electrolyzed solution, the separated hydrogen diluted with ambient air and vented to the atmosphere.
PCT/US2011/035175 2011-03-15 2011-05-04 Field of the invention WO2012125175A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2013505217A JP5593439B2 (en) 2011-03-15 2011-05-04 Method and system for ballast water and filtering
JP2011004837U JP3171387U (en) 2011-03-15 2011-08-18 Ballast water treatment system

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161452724P 2011-03-15 2011-03-15
US61/452,724 2011-03-15

Publications (1)

Publication Number Publication Date
WO2012125175A1 true WO2012125175A1 (en) 2012-09-20

Family

ID=46831034

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2011/035175 WO2012125175A1 (en) 2011-03-15 2011-05-04 Field of the invention

Country Status (2)

Country Link
JP (2) JP5593439B2 (en)
WO (1) WO2012125175A1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109789917A (en) * 2016-09-23 2019-05-21 懿华水处理技术有限责任公司 Ballast water treatment and neutralization
CN110213966A (en) * 2016-11-30 2019-09-06 懿华水处理技术有限公司 ballast water management system
WO2024017053A1 (en) * 2022-07-20 2024-01-25 深圳中科翎碳生物科技有限公司 Ship carbon dioxide tail gas treatment system

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101307166B1 (en) 2011-10-12 2013-09-11 (주) 테크로스 Ballast Water Treatment System
KR101600037B1 (en) * 2014-06-26 2016-03-07 (주)테크윈 A ballast water treatment system
JP6296070B2 (en) * 2016-01-20 2018-03-20 住友電気工業株式会社 Ballast water treatment system and control method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050178708A1 (en) * 2001-03-26 2005-08-18 Mark Farvell M. Filtration and purification system and method therefor
US20080000775A1 (en) * 2005-01-18 2008-01-03 Childers Harold E Ii System and Process for Treating Ballast Water
US20100116647A1 (en) * 2006-09-25 2010-05-13 Anja Kornmuller Ballast water treatment plant having filter, disinfection, instrumentation and control unit
US7776224B2 (en) * 2005-06-10 2010-08-17 Jfe Engineering Corporation Apparatus for treating ballast water and method for treating ballast water

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003181461A (en) * 2001-12-19 2003-07-02 Sanyo Electric Co Ltd Water treatment apparatus and water treatment method
JP4821361B2 (en) * 2006-02-20 2011-11-24 Ｊｆｅエンジニアリング株式会社 Ballast water treatment method
JP5034210B2 (en) * 2005-10-14 2012-09-26 Ｊｆｅエンジニアリング株式会社 Ballast water treatment equipment
JP4978002B2 (en) * 2005-12-07 2012-07-18 Ｊｆｅエンジニアリング株式会社 Ballast water treatment method
JP4844244B2 (en) * 2005-06-10 2011-12-28 Ｊｆｅエンジニアリング株式会社 Ballast water treatment apparatus and treatment method
US20080017586A1 (en) * 2006-02-15 2008-01-24 Matousek Rudolf C Ballast tank circulation management system
JP4822875B2 (en) * 2006-02-28 2011-11-24 三菱重工環境・化学エンジニアリング株式会社 Seawater detoxification device and ship equipped with this device
JP2007229576A (en) * 2006-02-28 2007-09-13 Mitsubishi Heavy Ind Ltd Apparatus for detoxifying liquid
JP4915295B2 (en) * 2007-06-19 2012-04-11 Ｊｆｅエンジニアリング株式会社 Ballast water treatment equipment
JP4737157B2 (en) * 2007-07-24 2011-07-27 Ｊｆｅエンジニアリング株式会社 Ballast water treatment apparatus and ballast water treatment method
JP2010269200A (en) * 2007-08-09 2010-12-02 Sumitomo Electric Ind Ltd Water treatment apparatus and water treatment method
JP5731195B2 (en) * 2007-08-15 2015-06-10 エヴォクア ウォーター テクノロジーズ エルエルシーＥｖｏｑｕａ Ｗａｔｅｒ Ｔｅｃｈｎｏｌｏｇｉｅｓｌｌｃ Method and system for treating ballast water
JP2009112908A (en) * 2007-11-02 2009-05-28 Mitsui Eng & Shipbuild Co Ltd Method of backwashing membrane filtration device
JP4816681B2 (en) * 2008-05-27 2011-11-16 Ｊｆｅエンジニアリング株式会社 Ballast water treatment method and apparatus
KR100883444B1 (en) * 2008-07-24 2009-02-17 (주) 테크윈 Apparatus and method for ballast water management
EP2313759A1 (en) * 2008-08-18 2011-04-27 Siemens Water Technologies Corp. Method and system for biofouling control of shipboard components
KR101129620B1 (en) * 2008-12-26 2012-03-28 삼성중공업 주식회사 anti-fouling system and control method thereof
WO2010093025A1 (en) * 2009-02-16 2010-08-19 株式会社クラレ Filtfering unit and ballast water production equipment provided with same

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050178708A1 (en) * 2001-03-26 2005-08-18 Mark Farvell M. Filtration and purification system and method therefor
US20080000775A1 (en) * 2005-01-18 2008-01-03 Childers Harold E Ii System and Process for Treating Ballast Water
US7776224B2 (en) * 2005-06-10 2010-08-17 Jfe Engineering Corporation Apparatus for treating ballast water and method for treating ballast water
US20100116647A1 (en) * 2006-09-25 2010-05-13 Anja Kornmuller Ballast water treatment plant having filter, disinfection, instrumentation and control unit

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109789917A (en) * 2016-09-23 2019-05-21 懿华水处理技术有限责任公司 Ballast water treatment and neutralization
EP3512770A4 (en) * 2016-09-23 2020-04-29 Evoqua Water Technologies LLC Ballast water treatment and neutralization
EP4342853A3 (en) * 2016-09-23 2024-05-15 Evoqua Water Technologies LLC Ballast water treatment and neutralization
CN110213966A (en) * 2016-11-30 2019-09-06 懿华水处理技术有限公司 ballast water management system
EP3512340A4 (en) * 2016-11-30 2020-08-12 Evoqua Water Technologies Limited Ballast water management system
US11148963B2 (en) * 2016-11-30 2021-10-19 Evoqua Water Technologies Llc Ballast water management system
AU2017367706B2 (en) * 2016-11-30 2022-08-18 Evoqua Water Technologies Limited Ballast water management system
US12084363B2 (en) 2016-11-30 2024-09-10 Evoqua Water Technologies Gmbh Ballast water management system
WO2024017053A1 (en) * 2022-07-20 2024-01-25 深圳中科翎碳生物科技有限公司 Ship carbon dioxide tail gas treatment system

Also Published As

Publication number Publication date
JP5593439B2 (en) 2014-09-24
JP3171387U (en) 2011-10-27
JP2013527798A (en) 2013-07-04

Similar Documents

Publication Publication Date Title
US8147673B2 (en) System and process for treatment and de-halogenation of ballast water
US8152989B2 (en) System and process for treating ballast water
JP5923190B2 (en) Method and system for treating ballast water
US7244348B2 (en) System and method for treatment of ballast water
JP7267196B2 (en) Ballast water management system
JPWO2005077833A1 (en) Liquid detoxification method and apparatus
WO2012125175A1 (en) Field of the invention
US20240002032A1 (en) Ballast Water Treatment and Neutralization

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2013505217

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11861037

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 11861037

Country of ref document: EP

Kind code of ref document: A1