Patent Publication Number: US-7905192-B1

Title: Integrated underwater surface cleaning and effluent treatment system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/856,473 filed Nov. 3, 2006, which is incorporated herein by reference. 
     This application is related to U.S. Non-Provisional patent application Ser. No. 11/998,978, filed Nov. 5, 2007, entitled “Underwater Surface Cleaning Vehicle For Integrated Cleaning and Effluent Treatment System”, which is based on U.S. Provisional Application No. 60/856,472, filing date Nov. 3, 2006, hereby incorporated herein by reference. 
    
    
     STATEMENT OF GOVERNMENT INTEREST 
     The following description was made in the performance of official duties by employees of the Department of the Navy, and, thus the claimed invention may be manufactured, used, licensed by or for the United States Government for governmental purposes without the payment of any royalties thereon. 
    
    
     TECHNICAL FIELD 
     The following description relates generally to a method and apparatus for underwater hull cleaning, and in particular to an integrated underwater hull cleaning and effluent treatment process. 
     BACKGROUND 
     Navy ships are periodically cleaned using open cycle cleaning devices such as, for example, submerged cleaning and maintenance platform (SCAMP) technology that utilizes integrated impeller and cleaning brush technology and results in the direct discharge of removed constituents such as, for example, biological fouling, hull coatings, and corrosion byproducts into surrounding water. Most antifouling coatings utilize heavy metals such as Cu and Zn as biocides that are released during cleaning operations at levels that can exceed water quality criteria. This has prompted governments to develop standards to manage this discharge or, in some cases, to prohibit open water cleaning of hulls with coatings that have antifoulants in them without special permission. 
     Waterborne underwater hull cleaning is critical to the worldwide operation and maintenance of Navy ships and impacts operating capability (e.g., speed and maneuverability), acoustic signature, fuel efficiency and the maintainability and lifecycle of critical systems including underwater hull coatings, impress current cathodic protection systems, and propulsion systems. 
     SUMMARY 
     Disclosed are systems and techniques for conducting integrated waterborne underwater hull cleaning using successive onboard vehicle processing and working fluid reuse with shore or pierside treatment of concentrated contaminants, including heavy metal toxicants in antifouling paint, with subsequent management and disposal of the wastestream by existing infrastructure. 
     In one aspect, the invention is an integrated hull cleaning and treatment system. The system includes a cleaning vehicle for removing fouling from an underwater hull surface of a docked watercraft and for drawing water entrained material away from the cleaning region. The system further includes a land treatment unit for treating liquid waste received from the cleaning vehicle and converting the liquid waste into dewatered solids and treated effluents. According to the invention, the land treatment unit has a gravity settling unit, a chemical treatment unit, a gravity thickening unit, and a land intake port for receiving the liquid waste from the cleaning vehicle. In this aspect, the invention includes a land intake hose having a first end and a second end, the first end attached to the cleaning vehicle and the second end attached to the land intake port of the treatment unit. 
     In another aspect, the invention is an environmentally friendly method of cleaning an underwater hull surface using an integrated hull cleaning and treatment system. According to this method, the system includes a cleaning vehicle, a land treatment unit, and a flexible intake hose attached at one end to the cleaning vehicle and at another end to the land treatment unit. In this aspect, the method includes, removing, with the cleaning vehicle, fouling material from an underwater hull surface of a docked watercraft, and drawing through the cleaning vehicle, a particulate flow of water entrained material removed from the cleaning region. The method further includes, conveying, via the flexible intake hose, liquid waste from the cleaning vehicle to the land treatment unit, and converting, in the land treatment unit, the liquid waste into dewatered solids and treated effluents. 
     In another aspect, the invention is a cleaning vehicle for cleaning an underwater surface, the cleaning vehicle having a cleaning deck. In this aspect, the cleaning deck includes a deck mouth, and one or more circulation pumps downstream of the deck mouth for initiating cleaning deck suction onto the underwater surface and for initiating a particulate flow of water entrained material removed by the cleaning deck. The invention also includes one or more abrasion devices for removing fouling from the underwater surface. The cleaning vehicle further includes a discharge port for discharging the particulate flow of water entrained material to a remotely located treatment unit. 
     Other objects, features, and advantages will be apparent from the description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is an exemplary flow diagram of an integrated hull cleaning and effluent treatment system according to an embodiment of the invention; 
         FIG. 1B  is an exemplary flow diagram of an integrated hull cleaning and effluent treatment system according to an embodiment of the invention; 
         FIG. 2A  is a schematic illustration of a cleaning vehicle for cleaning an underwater surface according to an embodiment of the invention; 
         FIG. 2B  is an exemplary side view illustration of a cleaning vehicle for cleaning an underwater surface according to an embodiment of the invention; 
         FIG. 2C  is an exemplary top view illustration of a cleaning vehicle for cleaning an underwater surface according to an embodiment of the invention; 
         FIG. 2D  is an exemplary illustration of a cleaning deck according to an embodiment of the invention; 
         FIG. 2E  is a schematic illustration of a cleaning vehicle for cleaning an underwater surface according to an embodiment of the invention; 
         FIG. 3A  is an exemplary flow diagram of a land treatment unit according to an embodiment of the invention; 
         FIG. 3B  is an exemplary top view illustration of a land treatment unit according to an embodiment of the invention; 
         FIG. 3C  is an exemplary side view illustration of a land treatment unit according to an embodiment of the invention; and 
         FIG. 4  is a flowchart of a method of cleaning an underwater hull surface and treating cleaning effluents according to an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     An integrated waterborne underwater hull cleaning system incorporates successive onboard vehicle processing and working fluid reuse with integrated treatment of concentrated contaminants, including metal toxicants in antifouling paint, and subsequent management and disposal of the wastestream by existing infrastructure. 
     Disclosed is an integrated waterborne underwater hull cleaning and integrated effluent treatment process that mitigates the release of removed constituents to surrounding waters.  FIGS. 1A and 1B  are exemplary flow diagrams of an integrated hull cleaning and effluent treatment system  100  for performing the above-recited functions. As illustrated in  FIGS. 1A and 1B , the system  100  includes a ship hull  110  having a hull surface  111 , the ship hull docked in relatively close proximity to a pier  140 . The system  100  further includes a cleaning vehicle  120 . As shown in  FIG. 1A , the system  100  may include a cleaning vehicle  120  that both cleans and treats cleaning effluents.  FIG. 1B  shows an embodiment in which the vehicle  120  cleans but does not directly treat cleaning effluents. 
       FIG. 1A  shows the cleaning vehicle  120  having a cleaning deck or shroud  122  and a pre-processing deck  124 . The cleaning deck  122  moves across the hull surface  111  to physically remove fouling and other undesired buildups from hull surface. The pre-processing deck  124 , via a reduced pressure gradient, sucks the particulate flow of removed fouling material and other cleaning material such as antifoulant coatings having heavy metal toxicants, along with surrounding water through the cleaning deck  122  into the pre-processing deck  124 . The surrounding water may be seawater, freshwater or another type of water depending on the environment in which the ship is docked. A flexible hose  123  may facilitate the transportation of the water entrained deposits from the cleaning deck  122  to the pre-processing deck  124 . As will be outlined below, the pre-processing deck  124  treats the water entrained material, separating the particulate flow into a separator effluent and a liquid waste concentrate of crushed fouling material. The separator effluent is directed back towards the cleaning deck  122  via line  127 . Line  127  may comprise an elongate flexible hose having a diameter of about 2 inches to 4 inches. The separator effluent may be reused to supplement further cleaning processes. Alternatively, the separator effluent may be discharged directly into the water.  FIG. 1  shows line  130  through which the concentrate of crushed fouling material is transported to a land treatment unit  150 , which may be located on a pier in the vicinity of where the ship is docked. The land treatment unit may also be situated on a ship such as a barge or on a platform or the like. Subsequent processing of the concentrate is performed in the land treatment unit. The line  130  may be a flexible hose of sufficient length and diameter, for example the hose may be about 400 feet to about 1000 feet in length, and about 1 inch to about 2 inches in diameter. Although the system  100  shows a ship hull  110 , the cleaning vehicle  120  may be used to clean other submerged surfaces. 
     In the embodiment shown in  FIG. 1B , the cleaning vehicle  120  moves across the hull surface  111  to physically remove fouling and other undesired buildups from hull surface. The removed material, which includes fouling and other cleaning material such as antifoulant coatings having heavy metal toxicants, along with surrounding water, is sucked in through a mouth of the cleaning vehicle by applying a reduced pressure gradient. The resulting particulate flow of liquid waste is discharged directly to the remote treatment unit  150 , via the line  130  described above. Regarding the cleaning vehicle  120  shown in  FIG. 1B , it should be noted that this vehicle may not necessarily be a single deck vehicle, but may have more than one deck. For example, the vehicle  120  of  FIG. 1B  may have a first deck that cleans and a second deck that is provided to control the cleaning process. Regarding the system  100  of  FIGS. 1A and 1B , it should be noted that although  FIGS. 1A and 1B  show a ship hull  110 , the cleaning vehicle  120  may be used to clean other submerged surfaces. 
       FIG. 2A  illustrates a cleaning vehicle  200  (within the dotted box) including a cleaning deck or shroud  220  as well as effluent treatment devices downstream of the shroud  220 , for cleaning an underwater surface, such as a hull surface.  FIG. 2A  shows a schematic illustration of the elements of the cleaning vehicle  200  according to an embodiment of the invention.  FIG. 2A  shows the cleaning deck  220  having cleaning units  225 , a solids-processing unit  250  downstream of the cleaning deck, a circulation and transfer pump unit  260 , also downstream of the cleaning deck, which may be one or more pumps. The pump  260  is directly coupled to the solids-processing unit  250 . The cleaning units may include one or more brushing devices and/or one or more nozzles.  FIG. 2A  also shows a separator unit  270  downstream of the solids-processing unit, which may be a hydrocyclone or similarly robust phase separator device.  FIG. 2A  also shows conduit lines  209 ,  210 ,  211 , and  212 . The conduit lines may be flexible hoses with line  209  connecting the cleaning deck  220  to the solids-processing unit  250 , and line  210  connecting the circulation pump  260  to the separator unit  270 . Line  211  also connects the separator unit  270  to the cleaning deck  220 . As shown, line  211  is a split line that is connected to the nozzles  227 . Line  212  connects the separator to a land treatment unit  300 . The land treatment unit  300  may be located on a pier in the vicinity of the docked ship. Alternatively, the land treatment unit  300  may be situated on a ship such as a barge, or on another platform. Lines  209  and  210  convey a particulate flow from the cleaning deck to the separator unit, and line  211  conveys recycled separator effluents to the cleaning deck  220 . The diameter of the lines  209 ,  210 ,  211 ,  212  may be adjusted to properly regulate flow-rates and maintain required pressure differences. For example, the diameter of the line  211  may be about 1.5 times the diameter of line  212 , with line  211  having for example, a diameter of about 3 inches to about 4 inches and line  212  having a diameter of about 1.5 inch to about 2.5 inches, with line  210  having a diameter of about 3 inches, and line  209  having a diameter of about 4 inches. In one particular embodiment, lines  210  and  211  may have a diameter of about 3 inches and line  212  has a diameter of about 2.0 inches. 
       FIGS. 2B and 2C  show side and top views respectively of the cleaning vehicle  200  according to an embodiment of the invention.  FIGS. 2B and 2C  show the arrangement of the various elements on the cleaning deck or shroud  220  and the pre-processing deck  240 , as well as the arrangement of the cleaning deck  220  and the pre-processing deck  240  with respect to each other.  FIG. 2B  shows the cleaning deck  220  pivotally attached to the pre-processing deck  240  via a linkage member  230 , which may allow for pivotal movement. The linkage member  230  may include a bar linkage arrangement to control the displacement of the cleaning deck  220  with respect to the pre-processing deck  240 .  FIGS. 2B and 2C  show the cleaning deck having guide wheels  229 , a diver control unit  236 , and a guard/hand rail  237  to enable an operator to safely and properly control and maneuver the cleaning deck  220 . As shown, the cleaning deck  200  also has a deck seal  228  to maintain a reduced-pressure contact with the hull surface.  FIGS. 2B and 2C  further illustrate a discharge port  233  for discharging the particulate flow, via a conduit such as  210  shown in  FIG. 2A , from the cleaning deck  220  to the pre-processing deck  240 . The top view of  FIG. 2C  shows recycling ports  235  for receiving recycled separator effluent/overflow, via a conduct such as  211  shown in  FIG. 2A , from the pre-processing deck  240 . 
       FIG. 2D  also shows the arrangement of the various elements on the cleaning deck  220  according to an embodiment of the invention.  FIG. 2D  shows deck suction mouth  222  for the intake of the particulate flow of water entrained fouling and other cleaning material. Also illustrated are reciprocating or rotating brushes  224 . The brushes  224  may be arranged in a circular manner and may comprise of steel, polypropylene, combinations thereof, or any other material used for bristles in brushes. The brushes are powered by one or more brush motors  226 , as shown in  FIG. 2C . The  FIG. 2D  also shows discharge nozzles  227  for directing and discharging recycled separator effluent. The nozzles  227  are configured and positioned to direct the discharge so that the discharge flow flushes material and other material from the brushes  224 . Additionally, the discharge flow from the nozzles  227  creates a water-current which directs into the deck mouth  222 , material cleaned from the hull surface  111 . Alternatively, the nozzles  227  may be directed to discharge the fluid directly onto the hull surface  111  to assist in the direct removal of fouling deposits. Although  FIG. 2D  shows three brushes  224 , the cleaning deck  220  may contain as many brushes as desired, including less than three brushes or more than three brushes. Similarly, regarding the nozzles  227 , the cleaning deck  220  may include as many nozzles as desired. 
     As stated above, the different elements of the pre-processing deck  240  are also shown in  FIGS. 2B and 2C .  FIG. 2B  shows the deck  240  having a solids-processing unit, which is a crusher  255 .  FIG. 2B  also shows the crusher motor  256  and crusher control lever  257  for operating the crusher  255 . The crusher  255  crushes and fractures solids removed during cleaning to for example about ⅜-in or smaller, while having minimal impact on flow. Incoming solids to be processed can be significant in size, for example as large as 4 inches.  FIG. 2B  also shows a circulation pump  265 , which may have a drive of about 30 HP. The pump  265  initiates the flow needed to generate shroud suction, the particulate flow of water entrained material, and subsequent downstream pressures for solids separation, separator fluid discharge or reuse, and concentrate transport. 
       FIG. 2C  shows the pre-processing deck  240  having a separator unit, a hydrocyclone  275 . The hydrocyclone  275  separates, concentrates and partitions the water entrained material into a separator effluent or overflow and concentrate or underflow streams.  FIG. 2C  also shows the deck  240  having an underflow discharge port  276  that discharges the concentrate towards the land treatment unit  300 , and overflow discharge port  277  that discharges/recycles the separator effluent to the shroud  220 . 
       FIG. 2E  is a schematic illustration of a cleaning vehicle  290  (within dotted box) for cleaning an underwater surface according to an embodiment of the invention similar to the system of  FIG. 1B , wherein the cleaning vehicle is designed to clean, but does not directly treat any of the cleaning effluents. As shown in  FIG. 2E , the cleaning vehicle  290  includes a cleaning deck or shroud  291  that has movably mounted brushes  292  for cleaning the underwater hull surface. The shroud  291  may optionally include nozzles  293  for supplementing the cleaning action of the brushes. A deck mouth  294  is also provided on the shroud  291 . As illustrated, the cleaning vehicle  290  also includes a pump  295 . The pump  295  may have a drive of about 30 HP, and initiates a reduced pressure through the deck mouth  294  to generate proper shroud suction between the shroud  291  and the hull surface to enable the cleaning operation. In this embodiment, the pump  295  also sucks through the mouth  294 , liquid waste which comprises the particulate flow of water entrained material and other removed materials from the hull. The liquid waste sucked through the shroud is pumped to the land treatment unit for processing. 
     It should be noted that brushes  292 , the optionally included nozzles  293 , and the deck mouth  294 , are of similar structure to similar elements shown in  FIG. 2D . Cleaning vehicle  290  may comprise a single deck structure or a multiple deck structure. For example, the vehicle  290  may have a first deck that cleans and a second deck that is provided to control the cleaning process. In a single deck structure, the pump  295  may be situated on the single deck. In a two deck structure, the pump  295  may be located on any of the deck structures. 
       FIG. 3A  is an exemplary flow diagram of a land treatment unit  300  according to an embodiment of the invention. As shown, liquid waste enters the land treatment unit  300  from the cleaning vehicle via line  301 . The liquid waste may either be a concentrate of crushed material, when the cleaning vehicle includes a pre-processing unit as illustrated in  FIG. 2A . Alternatively, the liquid waste may be the untreated water entrained material that is sucked in by a cleaning vehicle as illustrated in  FIG. 2E . The liquid waste may be pumped to the land treatment unit  300  at a rate of about 40 gallons per minute to a rate of about 100 gallons per minute, with a preferred rate of about 50 gallons per minute to about 60 gallons per minute. The unit  300  further includes a dispersion plate  305  and a primary settling tank  310  for the gravitation settling and separation of dense and more easily separable sludge from the liquid waste. In the settling tank  310 , the dense and more easily separable solids descends downwards under the influence of gravity to the bottom of the tank. A pump  315  pumps the sludge to one or more hoppers  320  where sludge is dewatered and metered. As shown in  FIG. 3A , the dewatered sludge is deposited into one or more drums  325 , and overflow is redirected, via line  321 , to the settling tank  310  to be re-processed. 
     As shown in  FIG. 3A , the overflow of less dense liquid waste from the settling tank  310  is directed to the chemical treatment unit  330  (enclosed in dotted lines). As illustrated, the chemical treatment unit  330  includes a neutralization chamber  331 , a coagulation chamber  332 , an injection chamber  333 , a maturation chamber  334 , and a clarifier  335 . The chemical treatment unit also includes a sand recirculation pump  345  and a hydrocyclone  336 . 
     In the neutralization chamber  331 , neutralizing chemicals such as sodium hydroxide are added to the liquid waste overflow to neutralize the waste. In the chemical co-precipitation chamber or coagulation chamber  332 , coagulants such as ferric chloride are added and mixed in a preferable rapid mix zone to ensure good coagulant dispersion. In the injection chamber  333 , ballasting sand and polymer are added to improve flocculation. Following the addition of sand and polymer in the injection chamber  333 , the flow is passed to a slow mix zone, maturation chamber  334 , to promote stable floc formation. The flocculated mixture is then passed to the clarifier chamber  335  for solid/liquid separation. The clarified effluent is collected in the effluent tank  340 . From the effluent tank  340 , clarified effluent is pumped by effluent pump  346 , via line or hose  347 , to either a public owned treatment works or other asset for final processing and discharge. Recirculation pump  345  pumps solids settled at the bottom of the clarifier  335  to the hydrocyclone  336 . In the hydrocyclone  336 , the sludge is separated from the sand. The reclaimed sand is reintroduced into the sand and polymer injection chamber  333  while the captured sludge is diverted to the sludge thickening unit  350  for further processing. 
     In the sludge thickening unit  350 , polymers are added to thicken the sludge, prior to slow stirring. Pump  355  then pumps the thickened sludge to hoppers  320  for dewatering. Although  FIG. 3A  shows the use of hoppers  320  to perform the dewatering process, other dewatering systems may be substituted or used in a complementary manner. For instance, a rotary press or other filtration system may be used. 
     The land treatment unit  300  is designed to operate in both manual and fully automated modes, operating in fill, start and shut-down (daily and final) sequences. In shutdown mode, the intake of liquid waste from the cleaning vehicle is terminated and substituted with relatively clean water, which may be surrounding water or hydrant/fire main water, to conduct final clean processing and flushing of the system. The intake of liquid waste may be stopped by design or due to sub-system failure, such as the underwater hull cleaning vehicle. The surrounding water or hydrant water enters the pier treatment unit via water intake line  302 . In the shut-down mode, various tanks or subsystem are systematically eliminated from use, cleaned and isolated. The process includes a combination of solids partitioning and separation within the system followed by isolating primary clarifier  310 , sludge thickening system  350  and finally, the chemical treatment module  330  itself prior to directing final contents of chemical treatment module  330  to bag filters  370 , via a drain tank and pump to the discharge riser location. In the shut-down mode, slurry that had been separated in the clarifier is diverted back to the hopper along line  349 , as shown in  FIG. 3A . 
       FIGS. 3B and 3C  are exemplary top and side views, respectively, of a land treatment unit  300  according to an embodiment of the invention. More specifically,  FIGS. 3B and 3C  show the arrangement of various elements of the land treatment unit  300  with respect to each other. In addition to the elements outlined in detail above with respect to  FIG. 3A , the top view of  FIG. 3B  shows the unit  300  having a hydraulic pump unit  303  for energizing a submersible pump and drawing surrounding water into the system for operating in the vehicle discharge failure or shut-down mode. As outlined above, the clean water is typically drawn from surrounding water but during final shutdown may be obtained from a hydrant.  FIG. 3B  also shows control panel  385  for controlling the overall operation of the land treatment unit  300 .  FIG. 3B  also shows drain pump  374 . The side view of  FIG. 3C  shows the unit mounted in a mobile trailer  380 .  FIG. 3C  also shows an automatic leveling system  382  for maximizing the flow and operation of the filtration systems of unit  300 . Also illustrated in  FIG. 3C  is a power generator  390  and a chemical storage and polymer mixing, maturation, storage and injection systems  395 . 
     This above-described apparatus enables integrated removing, capturing, containing, collecting, comminuting, separating, concentrating, discharging/reusing and transporting of hull cleaning wastewater from a moving vehicle, stationary platform or other submerged, partially submerged or floating base. The principal components and process may comprise an advanced waterborne underwater hull-cleaning vehicle. An environmentally friendly method of cleaning an underwater hull surface and treating cleaning effluents is outlined below. 
       FIG. 4  is a flowchart showing an environmentally friendly method of cleaning an underwater hull surface. Step  410  is the removing of fouling material from the underwater hull surface. The material is removed by the shroud of the cleaning vehicle, which contacts the underwater hull surface. Step  420  is the drawing of a particulate flow of water entrained material from the cleaning region. As shown in  FIGS. 2A and 2E , the cleaning vehicle includes a pump, which draws through the mouth of the shroud, removed fouling material as well as other material, such as antifoulant coatings removed from the cleaned surface. The material is sucked in along with water located in the cleaning region. 
     Step  430  is the conveying of liquid waste from the cleaning vehicle to the land treatment unit. The liquid waste is transported to the land treatment unit via a flexible hose of about 600 feet. The hose may have a diameter of about 1.5 inches to about 2.5 inches, depending on the consistency of the liquid waste. If the cleaning vehicle is one that includes a pre-processing unit as outlined with respect to  FIG. 2A , then the water entrained material is processed before it is transported to the land treatment unit. Consequently, the liquid waste comprises a processed form of the particulate flow of water entrained material. If the cleaning vehicle is one that does not include a per-processing unit as outlined with respect to  FIG. 2E , then because there is no pre-treatment of the particulate flow, the liquid waste transported to the land treatment unit is actually the particulate flow of water entrained material. 
     Step  440  is the converting of the liquid waste into dewatered solids and treated effluents. As outlined in  FIG. 3A , the land treatment unit utilizes gravity settling, chemical treatment with chemical co-precipitation, and gravity thickening, to produce dewatered solids and cleaner treated effluents. The system may also include rotary press or other technologies to perform solids separation and dewatering functions. Step  450  is the disposing of the dewatered solids into drums or other appropriate containers. Step  460  is the discharging of treated effluents into a holding tank or to a sewage system for further treatment. Steps  450  and  460  are outline in the description of  FIG. 3A . 
     Step  470  is the shut down and flushing of the pier treatment unit. As outlined with respect to the explanation of  FIG. 3A , the flushing includes the step of shutting off the supply of liquid waste from the cleaning vehicle. The shutting off of the supply of liquid waste may be intentionally done during shut down or may occur unintentionally during operation due to system malfunction. During shut-down alternate supply water is used for flushing that further includes the steps of pumping either surrounding water or hydrant water into the pier treatment unit via the water intake port, directing the water into the chemical treatment module, and filtering through the one or more bag filters, the final, treated contents of the unit. Step  470  may also include the discharge of filtered liquids, via the drain pump. 
     What has been described and illustrated herein are preferred embodiments of the invention along with some variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. For example, method steps may be performed in different orders. Those skilled in the art will recognize that many variations are possible within the spirit and scope of the invention, which is intended to be defined by the following claims and their equivalents, in which all terms are meant in their broadest reasonable sense unless otherwise indicated.