Method for obtaining alkalinity measurement of a sample

Abstract

The method and apparatus for obtaining alkalinity measurements include introducing a fluid sample; measuring the amount of phosphate in the fluid sample using a colorimetric reagent; measuring the pH of the fluid sample, wherein the pH of the fluid sample is related to the amount of hydroxide in the fluid sample; introducing an acid to convert all inorganic carbon to carbon dioxide; applying a positive potential to an SP3-substituted carbon electrode; introducing at least one acid reagent containing a metal catalyst in the reaction chamber before or substantially simultaneously with applying the positive potential to the SP3-substituted carbon electrode to convert the carbonates and the partially oxidized species to carbon dioxide; determining total organic carbon by detecting the amount of carbon dioxide produced by the oxidation; determining total organic carbon from oxidation of organic carbon species, and determining the obtained alkalinity based on the amount of phosphate, the amount of hydroxide, and the amount of carbon dioxide generated from the inorganic carbon.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 168,569, filed on March 31, 2021, and entitled “DERIVED ALKALINITY,” the contents of which are incorporated herein by reference. Background Art

[0003] The present application relates generally to determining alkalinity in aqueous samples, and more particularly to measuring alkalinity using measurements of phosphate, hydroxide, carbon dioxide, and oxidized species of the sample.

[0004] Ensuring water purity is crucial in many applications, such as in municipalities providing drinking water and in many other industries such as pharmaceutical, chemical, and other manufacturing sectors. Treatment of water may require that samples be properly measured for pH and alkalinity. Additionally, the presence of organic compounds in water may indicate a malfunction in filtration and / or other components and systems, which, if not checked, could damage expensive industrial systems, affect product quality, be detrimental to public health, and even impact profit margins. As an example, drinking water quality may require treatment with a disinfectant. The amount of disinfectant depends on accurate measurements of alkalinity and total organic carbon to prevent overuse of the reagent, which can lead to disinfection byproducts. Summary of the Invention

[0005] In summary, one embodiment provides a method for obtaining alkalinity measurements, the method comprising: introducing a fluid sample containing inorganic carbon into a reaction chamber of an analyzer, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted solid carbon electrode doped with a conductivity-enhancing composition; measuring the amount of phosphate in the fluid sample using a phosphate analyzer of the analyzer and a colorimetric reagent; measuring the pH of the fluid sample using a pH sensor of the analyzer, wherein the pH of the fluid sample is related to the amount of hydroxide in the fluid sample; introducing an acid reagent to convert the inorganic carbon into carbon dioxide, wherein the inorganic carbon comprises carbonates and bicarbonates; applying a positive potential to the SP3-substituted carbon electrode using a generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; introducing at least one acid reagent containing a metal catalyst into the reaction chamber prior to or substantially simultaneously with applying the positive potential to the SP3-substituted carbon electrode, the at least one acid reagent converting the carbonates and the partially oxidized species into carbon dioxide; determining total organic carbon by detecting an amount of carbon dioxide produced by the oxidation using at least one detector of the analyzer; and determining the resulting alkalinity based on the amount of phosphate, the amount of hydroxide, and the amount of carbon dioxide generated from the inorganic carbon.

[0006] Another embodiment provides an apparatus for obtaining alkalinity measurements, the apparatus comprising: a housing comprising: a reaction chamber, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted carbon electrode doped with a conductivity-enhancing composition; at least one detector; a phosphate analyzer; a pH sensor; and a generator; the apparatus for obtaining alkalinity measurements being configured to: receive a fluid sample containing inorganic carbon in the reaction chamber of the analyzer; measure the amount of phosphate in the fluid sample using the phosphate analyzer of the analyzer and a colorimetric reagent; measure the pH of the fluid sample using the pH sensor of the analyzer, wherein the pH of the fluid sample is related to the amount of hydroxide in the fluid sample; introduce an acid reagent to convert the phosphate analyzer into an inorganic carbon sample; converting inorganic carbon into carbon dioxide, wherein the inorganic carbon includes carbonates and bicarbonates; applying a positive potential to the SP3 substituted carbon electrode using the generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; introducing at least one acid reagent containing a metal catalyst into the reaction chamber before or substantially simultaneously with applying the positive potential to the SP3 substituted carbon electrode, the at least one acid reagent converting the carbonates and the partially oxidized organic matter into carbon dioxide; determining the total organic carbon by detecting the amount of carbon dioxide produced by the oxidation using the at least one detector of the analyzer; and determining the obtained alkalinity based on the amount of phosphate, the amount of hydroxide, and the amount of carbon dioxide generated by the inorganic carbon.

[0007] Yet another embodiment provides a product for measuring alkalinity in a sample, the product comprising a memory device storing code, the code being executable by a processor, and the code comprising: code for introducing a fluid sample containing inorganic carbon into a reaction chamber of an analyzer, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted solid-state carbon electrode doped with a conductivity-enhancing composition; code for measuring the amount of phosphate in the fluid sample using a phosphate analyzer of the analyzer and a colorimetric reagent; code for measuring the pH of the fluid sample using a pH sensor of the analyzer, wherein the pH of the fluid sample is related to the amount of hydroxide in the fluid sample; and code for introducing an acid reagent to convert the inorganic carbon into carbon dioxide, wherein the The inorganic carbon comprises carbonates and bicarbonates; code for applying a positive potential to the SP3-substituted carbon electrode using a generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; code for introducing at least one acid reagent containing a metal catalyst into the reaction chamber before or substantially simultaneously with applying the positive potential to the SP3-substituted carbon electrode, the at least one acid reagent converting the carbonates and the partially oxidized species into carbon dioxide; code for determining total organic carbon by detecting an amount of carbon dioxide produced by the oxidation using at least one detector of the analyzer; and code for determining a resulting alkalinity based on the amount of phosphate, the amount of hydroxide, and the amount of carbon dioxide generated by the inorganic carbon.

[0008] The foregoing is a summary and thus may contain simplifications, generalizations, and omissions of detail; accordingly, those skilled in the art will appreciate that the summary is illustrative only and is not intended to be in any way limiting.

[0009] For a better understanding of the embodiments and other and further features and advantages of the embodiments, reference should be made to the following description taken in conjunction with the accompanying drawings.The scope of the invention will be pointed out in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 An example method of obtaining alkalinity in a fluid sample is illustrated.

[0011] Figure 2 A conventional TOC analyzer system is illustrated.

[0012] Figure 3 An example SP3 substituted carbon electrode TOC analyzer is illustrated according to one embodiment.

[0013] Figure 4 An example flow chart of a method and system for obtaining alkalinity is illustrated.

[0014] Figure 5Example feed-forward and feedback of a fluid sample using influent and effluent measurements is illustrated. DETAILED DESCRIPTION

[0015] It will be readily understood that, in addition to the described example embodiments, the components of the embodiments as generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations. Accordingly, the following more detailed description of the example embodiments, as presented in the figures, is not intended to limit the scope of the claimed embodiments, but is merely representative of example embodiments.

[0016] Reference throughout this specification to "one embodiment" or "an embodiment" (or similar expressions) means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" or similar expressions in various places throughout this specification are not necessarily all referring to the same embodiment.

[0017] In addition, the described features, structures or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, many specific details are provided to provide a thorough understanding of the embodiments. However, those skilled in the relevant art will recognize that various embodiments can be practiced without one or more of these specific details, or using other methods, components, materials, etc. In other cases, well-known structures, materials or operations are not shown or described in detail. The following description is intended only to illustrate certain example embodiments by way of example and simply.

[0018] Conventional alkalinity measurements may have some limitations. Alkalinity is the buffering capacity of an aqueous sample. Alkalinity is an important parameter measured in source, distribution, industrial, and municipal process water matrices. In conventional methods, a strong acid can be gradually added to the sample solution for titration. The endpoints for phenolphthalein and total alkalinity can be pH 8.3 or pH 4.5, respectively. Titrations present safety risks due to the handling, presence, and storage of strong acids. In addition, conventional instruments may have performance and maintenance issues.

[0019] Additionally, harmful disinfection byproducts (DBPs) may form due to reactions between organic precursors found in water sources and disinfectants added to kill microorganisms. One use of alkalinity measurement is to reduce the concentration of organic precursors in the form of total organic carbon (TOC). This is achieved through precipitation of organic precursors such as humic acid.

[0020] For example, in the presence of disinfectants such as chlorine, these organic precursors are responsible for the formation of harmful disinfection byproducts (DBPs) in the water matrix. Simultaneous measurement of alkalinity and organic matter as TOC will support regulatory reductions in TOC and subsequently in the formation of DBPs. In addition, the method described here allows for the collection of raw water TOC and alkalinity samples at the same location.

[0021] A variety of total organic carbon (TOC) methods and technologies exist. However, many existing techniques require the use of hazardous reagents (e.g., strong acids and oxidants) and must be performed in harsh environments (e.g., under UV light, in high-temperature ovens, etc.) to properly perform the oxidation reaction. These issues have prompted the development of safer and more cost-effective electrochemical devices that can oxidize organic carbon and determine TOC levels in aqueous solutions.

[0022] One such device is a TOC analyzer manufactured and distributed by OI Analytical of College Station, Texas (i.e., the 9210e On-line TOC Analyzer), which utilizes thin diamond film electrodes doped with boron to oxidize organic materials to produce carbon dioxide (e.g., by generating hydroxyl radicals and ozone on the surface of the boron doped diamond (BDD) electrode). Boron is a better electrode material than carbon-based materials or other metallic materials (e.g., silver, gold, mercury, nickel, etc.) because these materials oxidize poorly and may eventually oxidize themselves. The OI TOC analyzer includes one or more sensors capable of detecting the carbon dioxide generated by the boron doped diamond electrodes. In one embodiment, a thick film SP3 substituted carbon region may be used, the advantages of which are described in U.S. Patent No. 10,724,984, entitled “SP3 SUBSTITUTED CARBONELECTRODE TOC ANALYSIS USING METALLIC CATALYST,” filed on July 29, 2017, the contents of which are incorporated herein by reference in their entirety.

[0023] However, existing TOC analyzers utilizing BDD electrodes may not be able to measure all oxidized carbon species. More specifically, hydroxyl radical oxidation of carbon species can produce two oxidation products—carbonate and oxalate, the ratio of which generally depends on the number of carbon atoms in the molecule (e.g., C1 (methanol) forms only carbonate (100%); C2 (ethanol) forms carbonate (~67%) and oxalate (~33%); and so on). Carbonate is measured in a CO2 gas analyzer by converting the carbonate into CO2 gas by adding acid. However, it is unclear whether current BDD TOC methods are able to fully measure the oxalate ratio, which may result in an incomplete measurement (i.e., an underestimation of the total TOC content). Additionally, thin-film electrodes have a short lifespan because the thin-film coating on the electrode undergoes delamination.

[0024] Research advances have found that adding manganese or other metal catalysts to the sample enables oxalate to be converted into CO2 gas, which can then be measured. However, these conventional methods still require the use of ozone to generate the active ingredient (i.e., hydroxyl radicals), which requires expensive ozone generators. Furthermore, the gas required for this technique is oxygen, which requires an oxygen concentrator in the analytical system.

[0025] Conventional instruments and methods cannot simultaneously determine both alkalinity and organic matter at the same location. This limitation in simultaneous measurement limits control over the amount of chemicals added to the system. For example, excessive levels of sodium bicarbonate may be added to reduce TOC. Without simultaneous monitoring, DBP levels may exceed regulatory or regulatory limits.

[0026] Therefore, the embodiment provides a method and system for simultaneously determining alkalinity and TOC. In one embodiment, real-time control can optimize chemical addition. The optimized chemical level can remove organic precursors. The optimized chemical level can reduce DBP formation. This optimization can be used for a variety of water source compositions. The embodiment provides a method for oxidizing organic carbon in an aqueous solution and measuring the total organic carbon produced by the oxidation process in combination with determining the alkalinity obtained by the fluid sample. In one embodiment, a fluid sample containing organic carbon is introduced into the reaction chamber of a total organic carbon analyzer. The reaction chamber can include an electrochemical cell having an SP3-substituted carbon electrode doped with a conductivity-enhancing composition (e.g., boron, etc.). In one embodiment, a colorimetric method can be used to measure the amount of phosphate in the fluid sample. In one embodiment, the pH value of the fluid sample can be measured or determined to determine the amount of hydroxide in the fluid sample. Then, the embodiment can apply a positive potential to the electrode to oxidize any organic matter in the fluid sample to its corresponding oxidation process. Embodiment can be introduced into this fluid sample by metal catalyst (for example, manganese, iron, nickel, chromium, another transition metal that can oxidize organic matter in fluid sample etc.).These metal catalysts will be oxidized to Mn (VII) of higher valence.These higher valence manganese species help the species (for example, oxalate etc.) of middle part oxidation to be converted into carbon dioxide, can detect and / or measure this carbon dioxide by at least one carbon dioxide detector / sensor then.In this process, Mn (VII) is converted back into Mn (II).This method has guaranteed to reclaim all oxidized carbon species fully.This system and method can obtain basicity to reduce treatment chemicals and reduce the formation of disinfection by-products.

[0027] The illustrated example embodiments will be best understood by reference to the accompanying drawings.The following description is intended only to illustrate certain example embodiments by way of example and in a simplified manner.

[0028] Now refer to Figure 1, an embodiment can measure the content of total organic carbon present in an aqueous sample. At 101, an aqueous fluid sample containing organic carbon (e.g., water from a source, a solution containing a dissolved sample, etc.) can be introduced into a TOC and alkalinity analyzer. In one embodiment, the TOC analyzer includes a suitable housing that is sealed to form a closed system in which the carbon dioxide generated by the oxidation process cannot escape from the system prior to detection. In one embodiment, the housing includes a reaction chamber configured to accommodate the aqueous fluid sample. The housing may also include a head space that may be configured to capture gaseous carbon dioxide. In one embodiment, the analyzer may be a stopped-flow design. The stopped-flow design may be configured to capture a fluid sample and perform steps for a volume that flows discontinuously through the analyzer.

[0029] In one embodiment, the reaction chamber may include an electrochemical compartment. The electrochemical compartment may include a plurality of electrodes (e.g., a working electrode, a reference electrode, a counter electrode, etc.), wherein the working electrode may be an SP3-substituted solid carbon electrode capable of oxidizing organic matter in an aqueous sample to produce carbon dioxide. In one embodiment, the SP3-substituted solid carbon electrode may be doped with a conductivity-inducing material (e.g., boron, etc.) that can increase the conductivity band of the SP3-substituted solid carbon electrode. For simplicity, most of the discussion herein will refer to boron as a conductivity-inducing material, however, it should be understood that other suitable atoms that can increase the conductivity band of the SP3-substituted solid carbon electrode may also be used. In one embodiment, the electrode may be immersed in and in contact with the aqueous fluid sample of the sample.

[0030] At 102, in one embodiment, the amount of phosphate in a fluid sample can be measured. The phosphate measurement can be performed using a colorimetric method. For example, a colorimetric reagent can be combined with at least a portion of the fluid sample. The phosphate in the fluid sample and the colorimetric reagent can form a color-forming complex. When a colorimetric reagent is used, the complex can provide an absorption band at a specific wavelength. Colorimetric measurements can be performed using a spectrophotometer, etc.

[0031] At 103, in one embodiment, the pH of the fluid sample can be measured. The pH sensor can be a specialized carbon electrode, a standard glass pH electrode, or the like. The pH of the sample can be used to determine the amount of hydroxide in the fluid sample. In one embodiment, the pH sensor and associated circuitry can be an add-on or component added to an existing TOC analyzer or device. In other words, pH measurement can be a retrofit component to a facility with an existing TOC measurement device. In one embodiment, the retrofit can include components for performing feedforward and feedback regulation of water treatment using influent and effluent measurements as discussed herein.

[0032] At 104, in one embodiment, an acid reagent may be introduced to convert inorganic carbon into carbon dioxide in the fluid sample. In one embodiment, the inorganic carbon may contain carbonates and / or bicarbonates. The inorganic carbon present in the sample as carbonates and bicarbonates prior to oxidation is injected into the NDIR cell in the form of carbon dioxide. The inorganic carbon in the form of carbon dioxide alone is used along with the amount of hydroxide and phosphate to determine the alkalinity achieved. The injection and generation of carbon dioxide from the inorganic carbon may be facilitated by the acid injection (see Figure 4 ).

[0033] At 105, in one embodiment, a positive potential can be applied to the SP3-substituted solid-state carbon electrode. A generator or other power generation source (e.g., an external battery, etc.) can be used to apply the potential to generate carbon dioxide at the surface of the SP3-substituted solid-state carbon electrode. In one embodiment, the positive potential can be a potential that is sufficiently large to fully oxidize organic compounds in the fluid sample into carbonate and oxalate oxidation products. For example, the potential can be 0.5 volts to 20 volts. In one embodiment, a galvanostat can be used to maintain a constant current through the electrochemical compartment.

[0034] In one embodiment, the oxidation process using a BDD electrode can include generating hydroxyl radicals via a one-electron, one-proton process in an acidic / neutral medium. The efficiency of hydroxyl radical generation depends on the pH of the sample solution. More specifically, at pH values above 9, little or no hydroxyl radical generation occurs. Therefore, in one embodiment, the pH can be maintained at ~1 to electrochemically generate hydroxyl radicals using one or more solid, free-standing SP3-substituted solid-state carbon electrodes. Due to the difference in thermal expansion coefficients between the substrate and the BDD, thin-film BDDs can experience thermal stress, which limits the current density that can be applied to these substrates. Thick SP3-substituted solid-state carbon electrodes lack a substrate and can therefore maintain structural and electrical integrity at higher currents. Such embodiments can eliminate the need for adding alkaline solutions and ozone, as required in conventional methods. Furthermore, the lack of a substrate in thick, solid, free-standing SP3-substituted solid-state carbon electrodes eliminates the delamination issue that occurs with thin-film BDDs.

[0035] At 106, in one embodiment, at least one acid reagent containing a metal catalyst can be introduced into the sample in the reaction chamber. In one embodiment, the at least one acid reagent can react with any carbonate in the sample to produce carbon dioxide gas. In one embodiment, the same or different acid reagents can contain a manganese (e.g., Mn(II)) catalyst. In one embodiment, for the Mn(II) catalyst, the pH value of the sample solution can be maintained at an acidic level to oxidize oxalate to carbon dioxide. The addition of the catalyst effectively ensures that the oxidation product is completely oxidized to carbon dioxide. In one embodiment, a fluid sample can be sprayed. Inert gas can be used for spraying. The inert gas can be nitrogen. In addition, the fluid sample can be heated. In one embodiment, the method can measure the initial pH value of the fluid sample and then directly purge the fluid sample with an inert gas.

[0036] At 107, in one embodiment, the carbon dioxide produced by the oxidation process can be measured. In one embodiment, the carbon dioxide can be bubbled into a collection chamber (e.g., a head space, etc.) where one or more sensors can be used to measure the carbon dioxide. In one embodiment, the head space can include a gas phase detector (e.g., a carbon dioxide sensor, etc.) capable of measuring the amount of gas phase carbon dioxide in the head space. In another embodiment, a liquid phase detector (e.g., capable of measuring the level of dissolved carbon dioxide in an aqueous phase, etc.) can be used in place of or in combination with the gas phase detector to obtain a complete measurement of TOC in the sample. In one embodiment, the measured carbon dioxide can be substantially proportional to the amount of organic carbon present in the aqueous sample.

[0037] Figure 2 An exemplary conventional analyzer system 200 is illustrated. The conventional system includes an oxygen module 201 that generates a sparge gas by concentrating oxygen from air using an oxygen concentrator. The conventional system includes two reagent introduction mechanisms 202 and 203 for introducing an acid and a base, respectively. Samples are introduced into the system using sample electronics 204. The conventional system also includes an ozone generator 205 that generates ozone to be used in a reactor. The reagents, sample, and ozone are conveyed to a reactor 206 where the sample is mixed. The reactor causes the production of carbon, which can then be measured using a CO2 analyzer 207. The exhaust gas from the CO2 analyzer 207 is then passed through an ozone destroyer 208 before being exhausted.

[0038] Use the methods described in this article and in Figure 3The system illustrated in FIG. 3 , can simplify conventional analyzer systems. For example, the exemplary embodiment of the system 300 described herein can use air rather than oxygen as the sparge gas. Thus, the oxygen module 201 can be removed and replaced with an airflow control unit 301. This not only removes the large oxygen module 201, but also reduces the amount of air required to generate the oxygen required by conventional systems. Furthermore, only a single reagent is required in the system 300 as described herein. Thus, one of the reagent pumps 202 and / or 203 can be removed from the system 300 (e.g., in FIG. 3 ). Figure 3 In the embodiment of the present invention, only the acid reagent pump 302 is present. The sample electronics 203 can also be simplified. The mixer portion of the reactor 206 can be eliminated and replaced with a solid carbon electrode 305 such as the SP3 described herein. In addition, the system 300 as described herein does not require ozone. Therefore, both the large ozone generator 205 and the ozone destroyer 208 can be eliminated. The system 300 as described herein can also result in a simpler CO2 analyzer 207, which is Figure 3 This is shown as 304. Additionally, the system requires fewer and smaller components, resulting in a smaller overall housing.

[0039] Now refer to Figure 4 , illustrating an example flow chart of a method and system for obtaining alkalinity. As described in detail above, a fluid sample can be injected into the device. A reagent or colorimetric reagent can be added and phosphate can be measured using colorimetry. In one embodiment, the pH of the fluid sample can be measured and the amount of hydroxide of the fluid sample can be measured. In one embodiment, the acid can convert all inorganic carbon into carbon dioxide. The carbon dioxide can be measured to determine the measurement results of carbonates and / or bicarbonates present in the fluid sample before the fluid sample is oxidized. In one embodiment, during the acid injection step, a gas can be used to spray the fluid sample. In one embodiment, an acid and a catalyst can be injected into the fluid sample. In one embodiment, the TOC of the fluid sample can be determined. In one embodiment, the phosphate measurement results, the hydroxide measurement results, and the measurement results of carbonates / bicarbonates generated from the inorganic carbon can be used to determine the alkalinity obtained ( Figure 1 , step 108).

[0040] Now refer to Figure 5, illustrates an example feedforward and feedback using the methods described herein. In one embodiment, the device and method can use alkalinity, TOC and other measurements to monitor water quality at influent and effluent locations. The device and method can determine the level of disinfection chemicals / reagents for a given volume of water to be treated so that disinfection byproducts are kept to a minimum or below a desired or specified level. In one embodiment, the device can measure influent and / or effluent characteristics. For example, influent measurements can include UV254, algae, natural organic matter (NOM), TOC and alkalinity measurements. Influent measurements can provide feedforward inputs to the system. For example, effluent measurements can include UV254, disinfectant / oxidant, disinfection byproducts, TOC and alkalinity measurements. Effluent measurements can provide feedback inputs to the system.

[0041] In one embodiment, influent and effluent characteristics can be used to determine the dosage of chemicals used to precipitate organic precursors, etc., to maintain the desired water quality for the facility. In one embodiment, influent and effluent characteristics can be used to determine the appropriate amount of treatment reagents (such as sodium carbonate, alkaline additives, etc.) to be applied to a fluid sample. In one embodiment, the method or apparatus can add treatment reagents to a water source. The addition of treatment reagents can be performed prior to or concurrently with treatment steps such as settling tanks, and prior to subsequent water treatment such as clarification, disinfection, etc.

[0042] In one embodiment, the method can simultaneously measure alkalinity and TOC to reduce DBP formation. For example, if alkalinity is low and organic matter is high, there is a high tendency for DBP formation. The amount of chemical required to prevent DBP formation can be calculated based on the alkalinity and TOC concentrations determined by the system and method.

[0043] In one embodiment, alkalinity levels can be optimized in real time through online monitoring and on-demand chemical addition to minimize DBP formation. The simultaneous measurement of alkalinity and TOC achieved by this system and method can generate buffer capacity and organic precursor concentrations, which can be used in a feedback loop to optimize chemical addition in real time, resulting in cost and chemical savings while effectively reducing DBP formation. This real-time control (RTC) can be used as a proactive tool to minimize DBP formation.

[0044] In one embodiment, simultaneous measurement of TOC and alkalinity at the influent and effluent in one system provides the ability to calculate the percent reduction of organic matter and its associated dependence on delta alkalinity. These calculations provide real-time insight into the efficiency of the precipitation process due to chemical addition. Dynamic, real-time chemical dosage control can be implemented to achieve maximum precipitation efficiency.

[0045] If the level violates the regulatory limit, the DBP measurement result at the effluent can provide an alarm, threshold, range, etc. The chemical treatment process performed upstream is automatically or manually managed to keep the DBP level below the required regulatory, desired or required limit. This event monitoring feature can be achieved by a system capable of measuring TOC and alkalinity simultaneously.

[0046] Therefore, the various embodiments described herein represent a technical improvement to conventional total organic carbon measurement techniques. Using the techniques described herein, embodiments can receive a fluid sample containing organic carbon and oxidize the sample to produce oxidation products, carbonates and oxalates. Embodiments can then introduce an acid reagent and a metal catalyst into the sample to convert the carbonates and oxalates into carbon dioxide, which can then be measured. Such techniques provide a more accurate method for measuring the total organic carbon content in a sample and provide a more cost-effective approach than existing methods.

[0047] As will be appreciated by those skilled in the art, various aspects may be embodied as systems, methods, or device program products. Thus, various aspects may take the form of entirely hardware embodiments or embodiments including software, which are generally referred to herein as "circuits," "modules," or "systems." Furthermore, various aspects may take the form of a device program product embodied in one or more device-readable media having device-readable program code embodied therewith.

[0048] It should be noted that various functions described herein can be implemented using instructions stored on a device-readable storage medium such as a non-signal storage device, where the instructions are executed by a processor. In the context of this document, a storage device is not a signal, and "non-transitory" includes all media except signal media.

[0049] The program code for performing the operations can be written in any combination of one or more programming languages. The program code can be executed entirely on a single device, partially on a single device, as a standalone software package, partially on a single device and partially on another device, or entirely on other devices. In some cases, the devices can be connected by any type of connection or network, including a local area network (LAN) or a wide area network (WAN), or can be connected by other means (e.g., by using the Internet through an Internet service provider), by a wireless connection (e.g., near field communication), or by a hard-wired connection (e.g., by a USB connection).

[0050] Example embodiments are described herein with reference to the accompanying drawings, which illustrate example methods, apparatus, and products according to various example embodiments. It should be understood that actions and functions may be implemented, at least in part, by program instructions. These program instructions may be provided to an apparatus (e.g., Figure 1 The machine can be produced by using a processor of the illustrated handheld measurement device) or other programmable data processing device so that instructions executed via the processor of the device perform specified functions / actions.

[0051] It should be noted that the values provided herein should be interpreted to include equivalent values indicated by the use of the term "about." Equivalent values will be apparent to one of ordinary skill in the art, but at least include values obtained by ordinary rounding of the final significant digit.

[0052] The present disclosure is presented for purposes of illustration and description and is not intended to be exhaustive or limiting. Many modifications and variations will be apparent to those skilled in the art. The exemplary embodiments are chosen and described in order to explain the principles and practical applications and to enable others skilled in the art to understand the disclosure of various embodiments with various modifications as may be appropriate for the particular use contemplated.

[0053] Thus, while illustrative example embodiments have been described herein with reference to the accompanying drawings, it will be understood that the description is not limiting and that various other changes and modifications may be implemented therein by those skilled in the art without departing from the scope or spirit of the present disclosure.

Claims

1. A method for obtaining alkalinity measurements, comprising: introducing a fluid sample containing inorganic carbon into a reaction chamber of an analyzer, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted solid carbon electrode doped with a conductivity-enhancing composition; measuring the amount of phosphate in the fluid sample using a phosphate analyzer of the analyzer using a colorimetric reagent; measuring a pH value of the fluid sample using a pH sensor of the analyzer, wherein the pH value of the fluid sample is correlated with an amount of hydroxide in the fluid sample; introducing an acid reagent to convert the inorganic carbon into carbon dioxide, wherein the inorganic carbon includes carbonates and bicarbonates; applying a positive potential to the SP3-substituted solid carbon electrode using a generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; Prior to or substantially simultaneously with applying the positive potential to the SP3-substituted solid carbon electrode, introducing at least one acid reagent containing a metal catalyst into the reaction chamber, the at least one acid reagent converting the carbonate and the partially oxidized organic matter into carbon dioxide; determining total organic carbon by detecting an amount of carbon dioxide produced by the oxidation using at least one detector of the analyzer; as well as The obtained alkalinity is determined based on the amount of the phosphate, the amount of the hydroxide, and the amount of carbon dioxide generated from the inorganic carbon.

2. The method according to claim 1, wherein Introducing the at least one acid reagent further comprises sparging with an inert gas.

3. The method according to claim 2, wherein: The inert gas includes nitrogen.

4. The method of claim 1, further comprising measuring an initial pH value of the fluid sample and then directly purging the fluid sample with an inert gas.

5. The method of claim 1 further comprising measuring an influent characteristic upstream of the analyzer and an effluent characteristic downstream of the analyzer.

6. The method according to claim 5, wherein: The influent characteristic is selected from the group consisting of alkalinity and total organic carbon.

7. The method according to claim 5, wherein: The effluent characteristic is selected from the group consisting of alkalinity and total organic carbon.

8. The method of claim 5, further comprising determining a desired concentration of a disinfecting chemical based at least in part on the influent characteristics and the effluent characteristics.

9. The method of claim 1, further comprising calculating a probability of formation of disinfection byproducts based at least in part on the obtained alkalinity and total organic carbon.

10. The method according to claim 1, wherein The reaction chamber of the total organic carbon analyzer includes a stopped-flow design for the fluid sample.

11. An apparatus for obtaining alkalinity measurements, comprising: A housing, comprising: a reaction chamber, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted carbon electrode doped with a conductivity-enhancing composition; at least one detector; Phosphate analyzer; pH sensor; and generator; The apparatus for obtaining alkalinity measurements is configured to: receiving a fluid sample containing inorganic carbon in the reaction chamber of the analyzer; measuring the amount of phosphate in the fluid sample using the phosphate analyzer of the analyzer using a colorimetric reagent; measuring a pH value of the fluid sample using the pH sensor of the analyzer, wherein the pH value of the fluid sample is correlated with an amount of hydroxide in the fluid sample; introducing an acid reagent to convert the inorganic carbon into carbon dioxide, wherein the inorganic carbon includes carbonates and bicarbonates; applying a positive potential to the SP3-substituted carbon electrode using the generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; introducing at least one acid reagent containing a metal catalyst into the reaction chamber prior to or substantially simultaneously with applying the positive potential to the SP3 substituted carbon electrode, the at least one acid reagent converting the carbonate and the partially oxidized organic matter into carbon dioxide; determining total organic carbon by detecting an amount of carbon dioxide produced by the oxidation using at least one detector of the analyzer; and The obtained alkalinity is determined based on the amount of the phosphate, the amount of the hydroxide, and the amount of carbon dioxide generated from the inorganic carbon.

12. The device according to claim 11, wherein Introducing the at least one acid reagent further comprises sparging with an inert gas.

13. The device according to claim 12, wherein The inert gas includes nitrogen.

14. The apparatus of claim 11, further comprising measuring an initial pH value of the fluid sample and then directly purging the fluid sample with an inert gas.

15. The apparatus of claim 11 further comprising measuring an influent characteristic upstream of the analyzer and an effluent characteristic downstream of the analyzer.

16. The device according to claim 15, wherein The influent characteristic is selected from the group consisting of alkalinity and total organic carbon.

17. The device according to claim 15, wherein The effluent characteristic is selected from the group consisting of alkalinity and total organic carbon.

18. The apparatus of claim 15, further comprising determining a desired concentration of a disinfecting chemical based at least in part on the influent characteristics and the effluent characteristics.

19. The apparatus of claim 11, further comprising calculating a probability of formation of disinfection byproducts based at least in part on the obtained alkalinity and total organic carbon.

20. A product for measuring alkalinity in a sample, comprising: A storage device storing codes, the codes being executable by a processor, and the codes comprising: code for introducing a fluid sample containing inorganic carbon into a reaction chamber of an analyzer, wherein the reaction chamber comprises an electrochemical compartment, and wherein the electrochemical compartment comprises an SP3-substituted solid-state carbon electrode doped with a conductivity-enhancing composition; code for measuring the amount of phosphate in the fluid sample using a phosphate analyzer of the analyzer and a colorimetric reagent; code for measuring the pH of the fluid sample using a pH sensor of the analyzer, wherein the pH of the fluid sample is related to the amount of hydroxide in the fluid sample; code for introducing an acid reagent to convert the inorganic carbon into carbon dioxide, wherein the inorganic carbon comprises carbonates and bicarbonates; code for applying a positive potential to the SP3-substituted solid-state carbon electrode using a generator of the analyzer, the positive potential being sufficient to oxidize organic matter in the fluid sample to produce carbonates and partially oxidized organic matter; prior to or substantially simultaneously with applying the positive potential to the SP3-substituted solid carbon electrode, introducing into the reaction chamber at least one acid reagent comprising a metal catalyst, the at least one acid reagent converting the carbonate and the partially oxidized organic matter into carbon dioxide; determining a code for total organic carbon by detecting an amount of carbon dioxide produced by said oxidation using at least one detector of said analyzer; and The code of the obtained alkalinity is determined based on the phosphate amount, the hydroxide amount, and the amount of carbon dioxide generated from the inorganic carbon.

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