Patent Application
20160178594
The present invention generally relates to apparatuses and methods for sensing a chemical characteristic of a sample and, more particularly, to an analyzer system and method for sensing a chemical characteristic of a fluid in a fluid flow.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Processes in many industries include a treatment step for waste water generated during the process. For instance, cooling circuits in industrial plants often employ water prone to biofouling, and in other industrial settings, such as in large-scale shipping operations, the amount of organic material allowed to exist in the waste water, or ballast water, is typically limited by various applicable regulations. As a result, various water treatment protocols are known. Typical water treatment protocols involve the addition of chlorinated compounds, such as sodium hypochlorite and chlorine dioxide, to the water to disinfect any biological material present in the water. Although such a chlorine treatment is effective at mitigating the effects of biological materials, overuse or underuse of the chlorinated compound can lead to additional problems. For instance, costs of treatment are greatly increased when too much chlorinated compound is used. Additionally, the outflow of oxidant compounds from industrial processes is often regulated by governing bodies that set an upper limit on the amount of oxidants allowed in the outflow. On the other hand, if too little chlorinated compound is used, the treatment may be ineffective, leading to fouling of the process apparatus or non-compliance with the applicable regulations regarding outflow of biological materials.
As a result, many industries rely on the rapid and accurate measurement of the amount of residual oxidizing material remaining in a sample of water. In fresh water, measurement of the amount of chlorine in the sample is referred to as the Total Residual Chlorine concentration (hereinafter “TRC”), and in sea water, the same measurement is referred to as Total Residual Oxidant concentration (hereinafter “TRO”), owing to the presence of iodide and bromide ions in sea water. Applications as diverse as shipping vessels, water treatment plants, manufacturing centers, thermoelectric and nuclear power stations, oil extraction apparatuses, chemical plants, food production facilities, water pipelines, or any other application in which water is used for manipulating the local environment, all rely on rapid and accurate measurement of residual oxidizing material remaining in the water.
For example, the shipping industry is subject to many regulations, e.g. from the U.S. EPA, regarding the purity of the water expelled from ballast water tanks, regarding both un-neutralized organic materials and excess chlorinated compounds. In general, when a shipping vessel discharges its cargo at one port, it loads one or more ballast tanks with water adjacent to its hull to help stabilize the vessel. The water that is taken on remains in the ballast tanks until the ship arrives at the next port to take on cargo. As the cargo is loaded, the ballast tanks are emptied through ballast pipes or ducts, either partially or fully, because the ballast water is no longer necessary due to the added weight of the cargo. Because the ship will travel great distances between the two ports, current regulations require biocidal treatment of the water held in the ballast tanks, prior to the ballast water being discharged, to help prevent the proliferation of non-native species of organisms. Practical matters require a similar treatment protocol to remove biological material capable of leading to biofouling of the tanks. The treated water in the ballast tanks should be monitored to control the amount of chlorine added and to ensure that enough chlorine is added to treat the ballast water effectively.
Analogously, the applications listed above also require monitoring of the oxidant materials in the outflow of those applications. Therefore, there is a need for an analyzer system for sensing a chemical characteristic of a fluid sample which is both accurate in its measurement capability and readily adaptable for use in various environments and sample measurement applications.
Certain exemplary aspects of the present invention are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the present invention might take and that these aspects are not intended to limit the scope of the present invention. Indeed, the present invention may encompass a variety of aspects that may not be explicitly set forth below.
In accordance with the principles of the present invention, and in the exemplary environment of a shipping vessel dumping ballast water into the proximate environment, an analyzer system according to one embodiment of the present invention may be installed after construction of the shipping vessel in many instances and may not require the input of any additional energy to sense a chemical characteristic of the flowing ballast water while it is being discharged from the shipping vessel. In other words, the analyzer system according to one embodiment of the present invention may be energetically self-contained. The analyzer system may be placed as close as possible to the ballast water outlet to ensure the highest quality measurement of the concentration of oxidant species at the location of its highest likelihood of environmental impact. Furthermore, the analyzer system according to one embodiment may be configured in such a manner that the sensor is protected from damage caused by standing sample water, such as ballast water, or by an analytical reagent used by the analyzer system, when the analyzer system is not in use.
According to one aspect of the present invention, an analyzer system is provided for sensing a chemical characteristic of a fluid sample. The analyzer system includes a sample inlet configured to receive a sample via the sample inlet; a reagent inlet configured to receive a reagent via the reagent inlet; a reaction zone in fluid communication with the sample inlet and the reagent inlet and being configured to receive the sample from the sample inlet and the reagent from the reagent inlet for mixing the sample with the reagent; and a sensor zone in fluid communication with the reaction zone. The sensor zone includes a sensor configured to sense the chemical characteristic of the mixed sample and reagent, and the sensor zone is configured to allow automatic drainage of the mixed sample and reagent away from the sensor after the sensor has sensed the chemical characteristic.
In another aspect of the present invention, the analyzer system includes a sample inlet configured to receive a sample via the sample inlet; a reagent inlet configured to receive a reagent via the reagent inlet; a sample reservoir in fluid communication with the sample inlet for receiving the sample from the sample inlet; an actuator having a first position and a second position, the actuator being configured to move from the first position to the second position in response to the sample being received in the sample reservoir; a reagent reservoir in fluid communication with the reagent inlet for receiving the reagent from the reagent inlet; a valve operatively coupled to the actuator being configured to release reagent from the reagent reservoir; a reaction zone in fluid communication with the sample reservoir and the reagent reservoir and being configured to receive the sample from the sample reservoir and the reagent from the reagent reservoir for mixing the sample with the reagent; and a sensor zone in fluid communication with the reaction zone. The sensor zone includes a sensor configured to sense the chemical characteristic of the mixed sample and reagent. Additionally, the reagent regulator is configured to release the reagent from the reagent reservoir in response to movement of the actuator from the first position to the second position.
In another aspect of the present invention, the analyzer system includes a sample inlet configured to receive a sample via the sample inlet; a reagent inlet configured to receive a reagent via the reagent inlet; an actuator having a first position and a second position, the actuator being configured to move from the first position to the second position in response to fluid flow; a reagent reservoir in fluid communication with the reagent inlet for receiving the reagent from the reagent inlet; a valve operatively coupled to the actuator being configured to release reagent from the reagent reservoir; a reagent outlet in fluid communication with the reagent reservoir; a reaction zone in fluid communication with the sample inlet and the reagent outlet and being configured to receive the sample from the sample inlet and the reagent from the reagent outlet for mixing the sample with the reagent; and a sensor zone in fluid communication with the reaction zone. The sensor zone includes a sensor configured to sense the chemical characteristic of the mixed sample and reagent. Additionally, the valve is configured to release the reagent from the reagent reservoir via the reagent outlet in response to movement of the actuator from the first position to the second position.
In another aspect of the present invention, a method is provided for monitoring the total residual oxidants present in a sample. The method includes providing the sample to the analyzer system of the present invention via the sample inlet; providing the reagent via the reagent inlet; mixing the sample and the reagent in the reaction zone; providing the mixed sample and reagent to the sensor zone; and sensing the total residual oxidants present in the sample.
According to yet another aspect, the present invention provides a method for sensing a chemical characteristic of a flowing fluid sample. The method includes, for example, providing the sample to an analyzer system; providing a reagent to the analyzer system; mixing the reagent and the sample; providing the mixed reagent and sample to a sensor zone; sensing a chemical characteristic of the sample; and removing the sample and reagent from the analyzer system. The power generated by the flowing fluid sample powers the steps of the method. Thus, no additional power is needed to sense the chemical characteristic.
The above and other objects and advantages of the present invention shall be made apparent from the accompanying drawings and the description thereof.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with a general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the present invention
Referring now to the figures in which like numerals represent like parts, and to
According to one embodiment as shown in
Optionally, calibration standard inlet 230a may provide a defined amount of calibration standard 32. Calibration standard inlet 230a may operate with the same principals as reagent inlet 230. However, calibration standard inlet 230a may be coupled to a valve with a mechanical time delay such that opening of the valve is delayed by a fixed amount of time to allow detection of the added calibration standard. The calibration standard 32 may be added either in lieu of or in combination with process water.
Solid reagent 36 allows the system to require little maintenance, with the reagent needing to be replaced less frequently than approximately every six months, for example, although the present invention is not intended to be limited to such a time period.
Float 48 is operatively linked to sealing valve 50 in pneumatic valve 52, which could be an on-off valve for example, through flapper 54, and pneumatic valve 52 is fluidly coupled to reagent reservoir 56. Although reagent reservoir 56 is shown downstream of pneumatic valve 52, the relative position of reagent reservoir 56 and pneumatic valve 52 is not material to the operation of the inventive system. Reagent 28 is stored in reagent reservoir 56 from a removable liquid reagent container (not shown). As the reagent is added to reagent reservoir 56, float 58 moves to a predetermined level, at which point float 58 activates sealing valve 60 to halt the flow of reagent into reagent reservoir 56. Float 58 is shown attached to reagent reservoir 56 through a hinging mechanism. However, float 58 may also freely float within the reagent reservoir 56.
Turning back to pneumatic valve 52, when float 48 moves flapper 54, thereby activating pneumatic valve 52, reagent from reagent reservoir 56 flows into reaction zone 518 where the reagent mixes with the sample from sample reservoir 46. Reaction zone 518 conveys the mixed sample and reagent to sensor zone 534. Sensor zone 534 includes at least one sensing electrode 20 and at least one reference electrode 22, which together comprise oxidants probe 24. The flow of the mixed sample and reagent subsequently carries the mixture to outlet 526, where the mixture is expelled into the water flow passageway 509. Optionally, second probe 44 may be incorporated in the sensor zone 534. Second probe 44 may be, for example, a temperature probe or a pH probe.
Turning back to pneumatic valve 52, when actuator 62 activates pneumatic valve 52, reagent from reagent reservoir 56 flows into reaction zone 618 where the reagent mixes with the sample from sample reservoir 46. Reaction zone 618 conveys the sample and reagent to sensor zone 634. Sensor zone 634 includes at least one sensing electrode 20 and at least one reference electrode 22, which together comprise oxidants probe 24. The flow of the mixed sample and reagent subsequently carries the mixture to outlet 626, where the mixture is expelled into water duct 609. Optionally, second probe 44 may be incorporated in the sensor zone 34. Second probe 44 may be, for example, a temperature probe or a pH probe.
Returning to the operation of the embodiment shown in
Sensor zone 834, which is downstream of outlet 872, includes at least one sensing electrode 20 and at least one reference electrode 22, which together comprise oxidants probe 24. When reagent is added, the sample and reagent mix in the area of the duct section 10a between the outlet 872 and oxidants probe 24. In principle, the size of reagent reservoir 868 will establish an upper limit as to the amount of reagent that can be delivered to oxidants probe 24.
In principle, analyzer system 813 could be modified to operate with sample sipping. In such an embodiment, the sipped sample could be conveyed into duct section 10a at a point downstream of paddle wheel 864, or sample sipping could be performed upstream of paddle wheel 864, with the flow of the process water driving activity of the analyzer system. For instance, analyzer system 813 could replace actuator 62, pneumatic valve 52, sealing valve 50, and reagent reservoir 56, of
The embodiment shown in
Sensor zone 934, which is directly above outlet 972, includes at least one sensing electrode 20 and at least one reference electrode 22, which together comprise oxidants probe 24. When cleaning solution is added, the sample and cleaning solution mix in the area of the duct section 10a between the outlet 972 and oxidants probe 24. In principle, the size of cleaning solution reservoir 968 will establish an upper limit as to the amount of cleaning solution that can be delivered to oxidants probe 24.
As described above, the embodiment shown in
The flow of process water causes paddle wheel 864 to rotate. Paddle wheel 864 is operatively linked to piston 866 in reagent reservoir 868. Linkage is made, for instance, by a rack and pinion system. The motion of paddle wheel 864 activates reagent reservoir 868 by moving piston 866 away from outlet 1072, drawing reagent 28 into reagent reservoir 868. As the flow of process water causes paddle wheel 864 to further rotate, piston 866 moves toward outlet 1072, pushing reagent 28 through outlet 1072 into a conduit to the reaction zone 518.
Sample is released from sample reservoir 46 and reagent 28 is released from reagent reservoir 868. Both sample and reagent 28 flow into reaction zone 518. Reaction zone 518 conveys the mixed sample and reagent to sensor zone 534. Sensor zone 534 includes at least one sensing electrode 20 and at least one reference electrode 22, which together comprise oxidants probe 24. The flow of the mixed sample and reagent subsequently carries the mixture to outlet 526, where the mixture is expelled into the discharge duct 10. Optionally, second probe 44 may be incorporated in the sensor zone 534. Second probe 44 may be, for example, a temperature probe or a pH probe.
The invention harnesses the power generated by the flowing process water to drive sample collection, addition of reagent, mixing, and draining. Thus, no additional power is needed to monitor the chemical characteristic of the fluid sample, and the analyzer system can be placed at a point close to the discharge point of the process water. Because the sample is collected and analyzed close to the discharge point, minimizing sensor response time, the results obtained should be superior to any other process water analyzer systems known to the inventors.
In addition to the disclosed analyzer system, the present invention also features a method for sensing a chemical characteristic of a flowing fluid sample. The method includes, for example, providing the sample to an analyzer system; providing a reagent to the analyzer system; mixing the reagent and the sample; providing the mixed reagent and sample to a sensor zone; sensing a chemical characteristic of the sample; and removing the sample and reagent from the analyzer system. The power extracted from the flowing sample powers the steps of the method. Thus, no additional power is needed to sense the chemical characteristic of the fluid sample,
The sample is provided to the analyzer system through a sampling device capable of extracting a small sample flow rate from a large flow rate. Indeed, approximately a 1 million-fold reduction in flow rate is obtainable without additional power added to the system in the form of a pump or valve. In an embodiment of the invention, the sample inlet is a sample sipping apparatus within a process water duct. Sample sipping pertains to a design that withdraws a constant and known portion from a stream within a duct. An exemplary flow sipper in a ballast duct has an elliptical opening and is at a grazing angle relationship to the flow stream contours within the process water duct to minimize clogging and wear due to silt and other large matter, but the present invention is not intended to be so limited.
The reagent is provided to the analyzer system through any means capable of storing and delivering the appropriate amount of reagent for conducting the analysis. The term “reagent” may also include probe cleaning solution. The reagent may be a gas-phase (vapor), liquid, or solid, and its chemical composition depends upon the particular application and sensing approach used. For instance, TRO may be sensed using an iodometric approach with potassium iodide and acetic acid. Chlorine, phosphate, and silica, may be sensed using colorimetry with 2-(Diphosphonomethyl)succininc acid, vannado-molybdate, or molybdic acid, ascorbic acid, and heteropolyblue, respectively, for example. Potentiometric sensing may be used to monitor sodium, chloride, and fluoride, using diisopropylamine vapor or formic acid, for example. One of ordinary skill in the art is capable of selecting the appropriate sensing technique and associated reagent to monitor the chemical characteristic of interest, and the present invention is not intended to be limited to any particular sensing technique or reagent.
As explained above, sensing of TRO may be performed using iodometric techniques. An exemplary iodometric technique is described in U.S. Pat. No. 4,049,382, entitled “Total Residual Chlorine,” the entire contents of which are incorporated herein by reference. Briefly, the sample stream is mixed with the reagent stream containing a dissociated complex of alkali metal ion and iodide ion, along with an excess amount of iodide ion. The iodide reacts with all residual chlorine in the sample and is converted to iodine. Two probes then measure the activity of the iodine, from which the total residual chlorine is determined.
When a liquid reagent is used, for example, the analyzer system may include an actuator, such as a float and flapper, a paddle wheel, or a propeller, each of which may move in response to the flow of sample through the ballast duct. The motion of the actuator may drive a mechanism that is capable of squeezing a bladder filled with the reagent or turning a release valve. When a solid reagent is used, the solid reagent may be configured to reside in the sample stream between the sample inlet and the reaction zone.
After providing the sample and reagent to the analyzer system, the reagent and the sample are mixed. Mixing can be accomplished, for example, by flowing the reagent and sample through a reaction zone together. The reaction zone may be configured in such a way that turbulence is created while the sample and reagent are flowing through the reaction zone. For example, the reaction zone may be a coiled pipe or a fluid passageway with one or more curved portions and one or more straight portions.
The mixed reagent and sample are provided to the sensor zone at the end of the reaction zone. The sensor zone may be configured to allow automatic drainage of the mixed sample and reagent away from the sensor after the sensor has sensed the chemical characteristic of the mixed sample and reagent. For example, the reaction zone may be arranged on a negative incline, and the sensor zone may continue that negative incline. In an alternate embodiment, the reaction zone may end with a slightly upward portion into the sensor zone, and the sensor zone may then be followed by a slightly downward flowing portion. A cross section of the latter embodiment would resemble an inverted U-shape with the sensor zone at the pinnacle of the inverted U.
The analyzer system is configured in a manner that allows the outflow of the mixed sample and reagent after sensing the chemical characteristic of the fluid sample. To prevent the need for additional energy input, the geometry of the system can be configured to take advantage of gravity and flow velocity. For instance, the sample inlet, reagent inlet, reaction zone, sensor zone, and system outlet, can all be arranged on a negative incline, with each successive zone spatially lower than the preceding zone. In the alternate embodiment discussed above, the inverted U-shape would cause the mixed sample and reagent to flow away from the sensor zone. In the latter embodiment, the inverted U can terminate at or near the process water outflow, which contains the remaining process water that was not collected in the sample inlet. Alternatively, the analyzer system may be configured to take advantage of pressure dynamics to draw the mixture away from the sensor zone.
Additionally, the embodiments shown above return the mixed sample and reagent to the process water duct, which is a feasible solution to waste-stream generation when the reagent is not particularly hazardous. However, the invention is not limited to only such waste reinjection. In situations where a hazardous material, such as chromium or mercury, is used as the reagent, one of ordinary skill in the art is capable of modifying the embodiments shown to allow for collection of a waste stream to hold for proper disposal.
While the various principles of the invention have been illustrated by way of describing various exemplary embodiments, and while such embodiments have been described in considerable detail, there is no intention to restrict, or in any way limit, the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art.
As various changes could be made in the above-described aspects and exemplary embodiments without departing from the scope of the invention, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.
The present application claims the filing benefit of U.S. Provisional Application No. 62/095,870, filed Dec. 23, 2014, the disclosure of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62095870 | Dec 2014 | US |
