The described embodiments relate to a method and a system for removing specific contaminants from water in a recirculating or linear treatment system.
A method and apparatus for removing specific contaminants from any aqueous solution in a recirculating or linear treatment system is disclosed. The circulation system often includes a chamber or fluid tank (typically holding an aqueous solution, such as fresh water or salt water) that stores aquaculture. The contaminants from the tank resulting from waste from the aquaculture (such as ammonia) are combined with various chemicals. The solution is then fed across electrical-powered plates of electrodes to generate a electrolytic reaction with the waste and chemicals in the solution to reduce bacteria and contaminants in the solution. The solution is then fed to filters and scrubbers (to clean the solution and remove byproducts resulting from the reaction) before being injected back into the tank or distributed to the point of use.
Methods for removing specific contaminants from any aqueous solution have been studied in various forms for several decades. However, their implementations and variations presented drawbacks. Electrolytic processes are executed in an atmospheric chamber, requiring liquid level controls, multiple pumps for each process instance, and a high probability of fluid overflow. These requirements potentially damage surrounding equipment or nearby power systems.
Further, undissolved gasses from each process instance create exposure to the atmosphere, potentially resulting in atmospheric contamination as some of the gasses are corrosive or flammable.
The difficulty in balancing multiple pumps and varying flowrates creates problems in applying the correct amount of power to the electrolytic cell, relative to the flowrate and water quality of the target aqueous solution.
When using systems to chlorinate or coagulate through electrolytic means, providing the correct chemical dosage is essential for effectively removing the contaminants. At breakpoint chlorination, all chlorine added to the solution is consumed by chemical reactions with the contaminants, resulting in little free available chlorine in the treated water. However, monitoring and adjusting the systems to achieve the breakpoint become burdensome due to the multiplicity of parameters, the relatively small target window of chemical dosage, and the contact time necessary to neutralize organic loads, combine chlorine and ammonia, effectively kill bacteria, and remove the byproducts at the final stage.
In a commercial or industrial application, missing a chlorine dosage target can damage products, equipment, or biological species. The process demands precision but achieving continuous precise dosage of chemicals would greatly increase the life of supplementary products, such as filtration media, components of the electrolytic cell, and the general infrastructure of the facility.
Conducting “breakpoint chlorination” is a complex process that must currently be controlled by highly experienced operators, thereby limiting the flexibility of a commercial operation.
In one aspect, a method for removing specific contaminants from an aqueous solution by disinfecting and removing organic compounds, ammonia, and ammonium ions that exist in equilibrium in the aqueous solution, the method includes pumping (with a pump having a variable pump speed) the aqueous solution from a holding vessel, either in a recirculation loop or a linear path, into a sealed and pressurized reaction chamber that includes positive electrodes and negative electrodes. From an electric power source, supplying a voltage and current to the positive electrodes and negative electrodes in the reaction chamber to generate chlorine from chloride ions infused within the aqueous solution that reacts with the ammonia and the ammonium ions in the aqueous solution to form chloramine. Using sensors, automatically collecting measurements from the aqueous solution, including one or more of Free Chlorine, Total Chlorine, Total Ammonia Nitrogen, pH, bacteria present, and Oxidation Reduction Potential, and automatically adjusting, in response to the measurements collected from the sensors, one or more of pump speed, injection of pH precursors prior to the reaction chamber, reaction chamber electrode voltage, and/or the current supplied to the positive electrodes and the negative electrodes, results in infusing chlorine at a specific ideal dosage. Once the process has been applied, the biproducts can be easily removed with a suitable filtration media.
In one aspect, a computing apparatus includes a processor. The computing apparatus also includes a memory storing instructions that, when executed by the processor, configure the apparatus to pump an aqueous solution from a holding vessel into a sealed and pressurized reaction chamber that contains positive electrodes and negative electrodes to generate chlorine from chloride ions infused within the aqueous solution that reacts with the ammonia and the ammonium ions in the aqueous solution, automatically collect with sensors measurements from the aqueous solution. The measurements include one or more of Free Chlorine, Total Chlorine, Total Ammonia Nitrogen, pH, bacteria present, and Oxidation Reduction Potential. The processor configure the apparatus to automatically adjust, in response to the measurements collected from the sensors, one or more of pump speed, injection of pH precursors, reaction chamber electrode voltage supplied to positive and negative electrodes, current applied to the positive and negative electrodes, and thereby controlling the infusion rate of chlorine.
In one aspect, an apparatus for removing specific contaminants from an aqueous solution by disinfecting and removing organic compounds, ammonia, and ammonium ions that exist in equilibrium in the aqueous solution includes a pump to move the aqueous solution from a tank or a holding vessel into a sealed and pressurized reaction chamber, an injection system to dose pH precursors into the aqueous solution such that the chlorine created in the reaction chamber reacts with the ammonia and the ammonium ions to generate chloramine, one or more sensors to automatically collect measurements from the aqueous solution, the measurements including one or more of Free Chlorine, Total Chlorine, Total Ammonia Nitrogen, pH, bacteria in the tank, and Oxidation Reduction Potential, and automatically adjusting, in response to the measurements collected from the sensors, one or more of pump speed, injection of pH precursors, reaction chamber electrode voltage, current, and infusion rate of the chlorine production. In some applications, adding beneficial minerals or additives may need to be added after the process to neutralize the pH or achieve a specific water quality metric, after the chemical reaction. This process is referred to as remineralization.
To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the figure number in which that element is first introduced.
In
The fed aqueous solution 104 is combined with an acid or base (pH precursor) from pH feed 116 (adjustable feed control) to neutralize the aqueous solution 104 and bring the pH of the aqueous solution 104 to neutral (or as close to a pH of 7.0 as possible) prior to and before entering a sealed and pressurized reaction chamber 110.
The aqueous solution 104 in the reaction chamber 110 is treated by applying electrolysis to the chloride solution (which is a brine, saline, or other aqueous based solution) being an effluent biproduct. In the reaction chamber 110, an adjustable power source (not shown) applies voltages and current to positive electrodes 118 and adjacent negative electrodes 120 at various electrode voltage levels to cause an electrolytic process, i.e., electrolysis. Electrolysis is applied to the aqueous solution 104 in reaction chamber 110, which also contains both sufficient chlorides, ammonium ions and a concentration of ammonia, to generate a reaction resulting in chloramine and chlorine. Moreover, the electrolytic process occurs in reaction chamber 110 that converts chloride ions infused within the aqueous solution 104 such that the aqueous solution 104 in the reaction chamber 110 reacts with the ammonia and the ammonium ions to generate chloramine and chlorine.
The output fluid from the electrolysis reaction chamber 110 now infused with chlorine, is then fed into a contact tank 112. Contact tank 112 in combination with a contact tank blending valve 122 (the combination referred to herein as an infuser), provides contact time between the generated free chlorine and bacteria to disinfect and reduce total organic load, kill and/or reduce bacteria and react with the ammonia and the ammonium ions in the aqueous solution. A contact tank blending valve 122 (for consistent flow, a flow rate control valve may be used) may be coupled in parallel with the contact tank 112 to control the contact time of chlorine and the solution and time aqueous solution flows in contact tank 112. The resulting fluid is flowed through a carbon filter 114 to remove the combined and created impurities and possibly fed into a remineralization blending system 124 (to add saline, acids, or bases to adjust the pH balance) with a contact tank blending valve 122, before being delivered to point of use or fed back into source aqueous tank 106.
The remineralization blending system 124 responds from feedback received from pH sensor 126 to adjust pH bleeding valve 128 to produce the target pH of the aqueous solution in tank 106. pH bleeding valve 128 controls the flow rate of the aqueous solution through remineralization blending system 124. An oxygen reducing gas may be infused into the aqueous solution 104 after the remineralization blending system 124 to adjust Oxidation Reduction Potential. The oxygen reducing gas infusion rate may be set by logic controller 302 (See
System 102 includes sensors 130, which are described in detail in connection with
A logic controller 302 (See
Pump 108p moves the aqueous solution 104 along a path from the holding vessel or tank 106 via the reaction chamber 110 via contact tank 112, via a carbon filter 114 and via a remineralization blending system 124 back to the holding vessel or tank 106. In one implementation, the aqueous solution 104 remains under pressure along and throughout the path.
Referring to
Referring to
Sensor bank 306 may include one or more sensors for detecting and monitoring voltage levels of the positive electrodes 118 and negative electrodes 120 in the reaction chamber 110, to monitor and determine a flow rate of the aqueous solution 104 passing through the reaction chamber 110, and a current applied to the positive electrodes 118 and the negative electrodes 120 in reaction chamber 110. Sensor bank 306 may also be coupled with one or more sensors to detect a presence of nitrites in aqueous solution 104.
Logic controller 302 may automatically provide an electrode plate voltage indication alarm signal (via a network connection and not shown) indicating an electrode plate degradation when voltage levels across the positive electrodes 118 and the negative electrodes 120 fall below a predetermined level at a preset current and a preset flow rate. Logic controller 302 may automatically change a flow of aqueous solution 104 being fed to the contact tank 112 by opening or closing the contact tank blending valve 122 to adjust the presence of nitrites in the aqueous solution 104.
The exemplary process in
Referring to
In Process 402, controller 302 determines if the drive pump 108 is operating in block 404. If it is not, in block 406, logic controller 302 issues a “start pumping” command. In block 408, logic controller 302 issues a system break, waits for a sensor input, and executes block 408. In Process 402, if controller 302 determines that the pump 108 is operating, then in block 410, logic controller 302 evaluates stored values and reads the pump 108 speed. In block 412, controller 302 reads a pump speed table that is preprogrammed and reads the pump power supply settings.
In block 414, logic controller 302 adjusts the pump speed of pump 108 based on preprogrammed table and then executes block 408.
In this description, Free Chlorine is referred to as FC, Total Chlorine is referred to as TC, Total Ammonia Nitrogen is referred to as TAN, and Oxidation Reduction Potential is referred to as ORP.
In block 416, logic controller 302 reads and stores influence values for sensor bank 306, including pH, ORP, TAN, FC, TC. pH sensors 126 and sensors 130 are shown in
In block 418, logic controller 302 determines if pH1 and pH2 are within parameters. If pH1 and pH2 are within parameters, logic controller 302 stores the pH control settings in block 420. If the pH1 level is high, logic controller 302 in block 422 sends a signal to cause acid to be injected using citric acid in pH feed 116. If pH1 is determined to be too low in block 424, logic controller 302 causes alkaline blending contact tank blending valve 122 to dissolve an alkaline agent into the fluid stream and then execute block 420 in which the logic controller 302 stores pH control settings.
In block 426, logic controller 302 determines if the power supply 304 is on. If the power supply 304 is on, logic controller 302 reads 320 in block 428 and determines if the TC is normal and if TAN is present, or if the FC is too high. If the TC is normal in block 430, the power settings are stored. If TAN is present, then power, current and/or electrode voltage provided to reaction chamber 110 using the positive electrodes 118 and negative electrodes 120 is increased in block 432, before executing block 430. If FC is high in block 434, the power and/or electrode voltage provided to the positive electrodes 118 and negative electrodes 120 in reaction chamber 110 is decreased, and the power and/or electrode voltage settings are stored in block 430.
If, in block 426, the logic controller 302 determines power supply 304 is off, in block 436, logic controller 302 reads 320. In block 438, logic controller 302 issues a “start power” command based on an estimate of TAN, Nitrogen, pH, and ORP before executing block 430.
In block 440, logic controller 302 determines whether the contact tank blending valve 122 is activated. If the contact tank blending valve 122 is not activated, in block 442, logic controller 302 issues a “start Valve” command, i.e., a disinfection setting.
If the contact tank blending valve 122 is activated, in block 434, a determination is made in block 438 regarding a disinfection setting. In one implementation the disinfection setting is determined by the quantity of bacteria present in the tank 106 from the sensor readings, using the method previously referenced. In another implementation, the disinfection setting can be set by the user (or automatically with logic controller 302) of the system 102, based on levels of bacteria present in the tank 106. Logic controller 302 may automatically change a flow of aqueous solution 104 being fed to the contact tank 112 by opening or closing the contact tank blending valve 122 (as described in block 444, block 446 and block 448) to adjust the presence of nitrites in the aqueous solution 104. If the disinfection setting is off, logic controller 302 stores the open position setting of contact tank blending valve 122 in block 444. If the disinfection setting is low, in block 446, logic controller 302 sets the contact blending valve opening to 50%. If the disinfection setting is high, logic controller 302 sets the blending valve opening to 100% in block 448 and then executes block 444.
After executing block 444, logic controller 302 executes block 450 by storing all values and by restarting the loop. The logic controller 302 restarts the loop by re-executing block 404 to determine whether pump 108 is still running.
While the above description identifies, describes, and details several novel features of the invention, as applied to a preferred embodiment, it should be understood that various omissions, substitutions, and changes in the form and details of the described embodiments may be made by those skilled in the art without departing from the spirit of the invention. Accordingly, the scope of the invention should not be limited to the foregoing discussion but should be defined by the appended claims.
This application claims the benefit of U.S. provisional application No. 63/237,087, filed on Aug. 25, 2021
Number | Date | Country | |
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63237087 | Aug 2021 | US |