US20090242419A1

US20090242419A1 - On-site on-demand chlorine gas generator

Info

Publication number: US20090242419A1
Application number: US12/057,698
Authority: US
Inventors: John W. Aldridge; Patrick Ryan Aldridge
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-03-28
Filing date: 2008-03-28
Publication date: 2009-10-01

Abstract

A method and device to produce chlorine gas on demand utilizing an electrolytic process for water treatment. The electrolytic components are mounted in a substantially rectangle shaped assemblage. This design of the rectangle shape assemblage ensures that the device consistently operates at peak efficiency. The device monitors and adjusts chlorine generation for changing demands and conditions for the production of disinfected water.

Description

BACKGROUND OF INVENTION

This invention relates generally to the field of water disinfection. More specifically, this invention relates to a device and method for generating chlorine gas on site and on demand for the disinfection of water. The device provides a method and means to create chlorine gas from commonly available materials. The chlorine gas is generated directly within the water to be treated. The device is a compact and efficient on-site water disinfection tool.
Chlorination of drinking water began in Jersey City, N.J. in 1908. Soon thereafter, other United States towns and cities adopted water chlorination for drinking water. This resulted in the virtual elimination within the United States of such waterborne diseases as cholera, typhoid, dysentery and hepatitis A. Chlorinated drinking water's chief benefit is the protection of public health through the control of these waterborne diseases, and it continues to play an important role in controlling pathogens in water that cause human illness; the virtual absence of waterborne diseases such as typhoid and cholera in developed countries can be attributed in large part to the chlorination of drinking water. Chlorine has a broad spectrum germicidal potency and persistence in water distribution systems, providing residual protection against microbial regrowth. It is also used to control taste and odor problems by oxidizing many naturally occurring substances such as foul-smelling algae secretions, odors from decaying vegetation, hydrogen sulfide and ammonia. Chlorine is commonly used in this manner because it is readily available, inexpensive, effective, easy to use, and has a positive residual effect.
However, untreated or inadequately treated drinking water supplies remain the greatest threat to public health, especially in developing countries. In poor and underdeveloped countries, diseases such as cholera, typhoid and chronic dysentery are endemic. Unfortunately, safe drinking water in many of these areas is practically unavailable and the ability to treat drinking water is for the most part nonexistent. This lack of untreated water is due in significant part, to poverty, poor understanding of water contamination, and lack of a treatment and delivery infrastructure. Around the world, more than 25,000 people die each day due to diseases associated with dirty drinking water.
In addition to ensuring supplies of safe drinking water for everyday use, chlorine has germ killing qualities and, as a result, has been utilized throughout the world to provide safe drinking water in response to natural disasters such as floods and hurricanes. These disasters wash high levels of microorganisms into existing water sources. In the United States and elsewhere, chlorine treatment for water has been utilized during disaster responses. For example, chlorine treatment was used to make the drinking water safe for the victims of floods in the Midwestern United States in 1993. In 1991 the water supply in New Bedford, Mass. was contaminated by high levels of bacteria as a result of Hurricane Bob; chlorine was used to correct the tainted water. When tropical storm Thelma devastated the Philippines and contaminated its water supply in 1991, large shipments of chlorine were among the first relief supplies to reach that country.
Over 98 percent of United States waste water and water supply systems use chlorine or chlorine based disinfectants that provide lasting residual protection from waterborne diseases throughout the distribution system from the treatment plant to the consumers' taps. Chlorine is also used for water disinfection in chicken processing plants, bottle washing stations, bottled water plants, and fruit and vegetable processing.
However, despite its proven value, chlorine is a hazardous material. It is difficult and expensive to store, and utilizing chlorine in its most common form creates hazards for both the user and the end consumer of the treated water. Currently, chlorine is commonly stored by municipalities in 150 lb, 1 ton steel bottles, or 90 ton railroad tank cars. Not only does this storage method create control and space issues due to the bulk of the storage containers, this method of storing necessary volumes of chlorine has also raised significant concerns of a terrorist threat. The containers, and in particular the large railroad tank car of chlorine poses the potential for massive lethal effects if exploded or caused to leak. However, even without the threat of terrorist activity, a safer and more controllable means of chlorinating water is needed. In particular, what is needed, is a device and method for chlorinating water onsite and on-demand for a particular application. An appropriate solution should also adjust to the needs of a particular application, and should avoid unnecessary storage of volatile chlorine. Such a solution should further utilize commonly available resources for the generation of the chlorine necessary for water treatment.

SUMMARY OF THE PRESENT INVENTION

It is an objective of this invention to concentrate all of the positive effects of chlorine into a non-threatening vehicle, thus eliminating the need for on site storage of chlorine by producing chlorine on demand at the point of treatment. It is a further objective of this invention to provide a system and method of chlorine generation that can be operated either manually or automatically as dictated by site conditions and by using locally available chemicals.
These and other objectives can be achieved by a chlorine gas generator comprised of two rectangular tanks with an external flange projecting from one side of each tank wherein each flange is of a suitable shape to allow the tanks to be mechanically attached flange to flange. The flange material is preferentially polyvinyl chloride, but may be any other suitable non-reactive material. The top of each tank may or may not have a removable top plate, depending upon the application and withdrawal ports. Each tank comprises a storage compartment, for reactive materials that will allow generation of chlorine by the device. One of the tanks comprises an anode compartment and has the positive lead of a low voltage direct current power supply connected to an electrode mounted in the tank's associated flange. The second tank comprises a cathode compartment, and has the negative lead of the power supply connected to an electrode mounted in its associated flange.
The anode and cathode compartments of the present invention are separated by an ion-selective membrane located between the electrodes within the bolted flange assembly. The ion-selective membrane is effective for preventing the passage of chlorine ions through said ion-selective membrane, so chlorine gas will collect in the anode compartment. When a brine solution is added to the anode compartment, a caustic solution is added to the cathode compartment, and an electrical current is applied to the electrodes, electrolysis takes place and chlorine gas is produced in the anode compartment. This reaction is: 2Na⁺(aq)+2Cl⁻(aq)+2H₂O(l)→Cl₂(g)+H₂(g)+2Na⁺(aq)+2OH⁺(aq). It is the chlorine gas (Cl₂(g)) product that is utilized by the present invention to chlorinate the water. The brine solution is generally produced by adding solid sodium chloride to the brine tank with water, producing the brine solution and the source of the Cl⁻(aq) that is then converted to chlorine gas in the anode compartment for capture and use. The caustic solution in the cathode compartment is generally produced by adding sodium hydroxide to water in the cathode compartment. The withdrawal port of the anode compartment is connected to a venturi injector so that as the water intended for treatment flows through the injector the chlorine gas is drawn from the anode compartment and aspirated into the water stream for disinfection.
A main electrical control cabinet preferentially consists of a direct current power supply, a programmable logic controller, a human-machine interface panel, a hydrogen and chlorine gas detector, control relays, and selector switches. Pilot lights are used to monitor and control the amount of chlorine gas produced by the generator. The desired amount of chlorine gas in pounds per day to be produced is entered in the human-machine interface panel located on the front of the main electrical main electrical control cabinet; the maximum amount is determined by the capacity of the chlorine generator and is only functionally limited by the size constraints of the device and the location.
The logic controller adds brine from the brine tank to the anode compartment via the brine pump in order to maintain the proper concentration of brine. The logic controller also adds water via the solenoid valve to the cathode compartment in order to maintain the proper caustic concentration. The amount of chlorine gas being produced can be increased or decreased, either manually through the human-machine interface panel or by data input to the logic controller, in order to maintain the desired rate of chlorine production. The data input can be generated by sensors in either or both the anode and cathode chambers, or can be generated by sensors within the water supply itself.
The apparatus as disclosed herein is designed to be safe, reliable, and require only a minimal amount of maintenance to operate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of the primary components of the chlorine generator system.

FIG. 2 is an expanded view of the electrolytic cell for a single cell system.

FIG. 3 is a view of the primary components of the main electrical control cabinet.

FIG. 4 is a first flow chart of a logic controller software program for the present invention in accordance with a preferred embodiment.

FIG. 5 is a second flow chart of a logic controller software program for the present invention in accordance with a preferred embodiment.

FIG. 6 is a third flow chart of a logic controller software program for the present invention in accordance with a preferred embodiment.

FIG. 7 is a fourth flow chart of a logic controller software program for the present invention in accordance with a preferred embodiment.

DESCRIPTION OF A PREFERRED EMBODIMENT

For the purposes of understanding the principles of the invention, reference will be made to illustrated embodiment, and specific language will be used to describe the same. It should be understood that no limitation of the scope of the invention is intended, and that further alterations, modifications, and applications of the principles of the invention as illustrated herein will be understood by one skilled in the art to which the invention relates, and without deviation from the scope of the present invention.
Referring now to FIG. 1, potable water 1 enters a mineral tank 2. The mineral tank 2 may be construction of polyglass or other suitable material, and the mineral tank 2 preferentially contains ion exchange resin beads which function to remove calcium and magnesium ions from the potable water 1. The output of the mineral tank 2 is mineral free potable water 3, which then flows to the brine tank 4 as well as the cathode tank 20 through the cathode tank 20 fill port 29. Flow to the cathode tank 20 through the cathode tank 20 fill port 29 is controlled by a solenoid valve 22, and monitored utilizing a flow rate sensor 21. The mineral free potable water 3 enters the brine tank 4 through fill port 5 and mixes with commonly available food grade salt or suitable substitute, producing saturated brine. As the brine solution is utilized by the system, make-up potable water 1 is added to the system.
The anode 14 and cathode 15 compartments comprise two substantially rectangular polyvinyl chloride tanks comprising an anode tank 13 and a cathode tank 20. It will be understood by those skilled in the art that other geometric shapes, sizes and suitable materials may be substituted for the construction of the anode tank 13 and the cathode tank 20. The anode tank 13 and the cathode tank 20 may be constructed in various sizes depending upon the application and volume of treated water desired; it will be understood by those skilled in the art that the present invention may be modified in dimensions and capacity without deviating from the scope of the invention so that the invention may be utilized in small, portable and self-contained form for private and/or home use up to larger, industrial and large population applications as well as adapting the present invention to the physical limitations of location of the device. Changes in the size of the constituent components to correspond to various geometric shapes and sizes of the anode tank 13 and the cathode tank 20 may be accomplished by increasing or decreasing the sizes of the ion-selective membrane 39, anode 14, cathode 15, mineral tank 2, and associated water flow components (piping, flow valves, etc.), and still be within the scope of the present invention.
In a preferred embodiment the anode tank 13 and cathode tank 20 are each thirty six inches high and thirteen inches wide, twenty inches long and are connected together by extended twenty four inch square flanges 40 and 41, which are connected together end to end by a mechanical fastening device such as bolts or clamps. The overall structure of the anode tank 13 and the cathode tank 20 is a substantially rectangular tank separated by the ion-selective membrane 39. The output and/or the performance of the cell, in the present configuration, is substantially unaffected by the horizontal or vertical length of the anode tank 13 and the cathode tank 20. The anode tank 13 and the cathode tank 20 may further comprise overflow outlets 11 and 18.
The top of each tank may further comprise removable plates 10 and 17, and withdrawal ports 25 and 26. The anode tank 13 has the positive lead of a low voltage direct current power supply 67, located in the main electrical control cabinet 27, electrically connected to the anode 14, with the anode 14 mounted at the mechanically fastened end of the anode tank 13 within the flange 40. The cathode tank 20 has the negative lead of a low voltage direct current power supply 67 electrically connected to the cathode 15, with the cathode 15 mounted at its mechanically fastened end within the flange 41. Each tank will also preferentially comprise overflow outlets 11 and 18.
The anode tank 13 further comprises the following components: a brine inlet 28, a drain valve 30, an overflow port 11, and a cooling tube 32 with a cooling water inlet port 33 and a cooling water outlet port 34. There may also be provided within the anode tank 13 a combination temperature/conductivity sensor 12 mounted in the anode tank 13. The brine inlet 28 provides brine solution from the brine tank 4; the flow of the brine solution to the brine inlet 28 is controlled via a brine pump 9, which serves to pump brine solution from the brine tank outlet 8, and the brine pump 9 is electrically connected to and controlled from the main electrical control cabinet 27. The temperature/conductivity sensor 12 determines the concentration of salt within the brine solution in the anode tank 13, causing the brine pump 9 to be switched on as necessary.
The cathode tank 20 may further comprise the following components: a makeup water inlet 29, a drain valve 31, an overflow port 18, and a cooling tube 35 with a cooling water inlet port 36 and a cooling water outlet port 37. There may also be provided within the cathode tank 20 a combination temperature/conductivity sensor 19 mounted within the cathode tank 20.
It will be understood that, for each tank, the combination temperature/ conductivity sensors 12 and 19 may constitute separate sensors, one each for temperature and one each for conductivity. Providing separate sensors in such a manner will not cause the design or operation of the invention to deviate from the scope and spirit of the invention.
Cooling water is supplied to the anode tank 13 and the cathode tank 20 from the source water 16, and pumped by the cooling pump 6. The cooling pump 6 is electrically connected to the main electrical control cabinet 27, and turned on and off in response to temperature changes within the anode tank 13 and the cathode tank 20 as detected by the combination temperature/ conductivity sensors 12 and 19.
The source water 16 flows to the venturi injector 42, while the flow rate sensor 7 monitors the flow rate of the source water 16 to the venturi injector 42. The flow rate sensor 7 is electrically connected to the main electrical control cabinet 27, and provides alarm feedback for the control system (FIG. 6). It will be understood by those skilled in the art that the source water 16 may be provided as pressurized or pumped from the source, or a suitable water pump may be utilized external to the present invention in order to provide flow of the source water 16.
The chlorine gas withdrawal port 25 is connected to the venturi injector 42; as source water 16 flows through the venturi injector 42, chlorine gas is drawn out of the anode tank 13 through the withdrawal port 25, and the chlorine gas is mixed into the source water 16. The resulting chlorinated water 44 is then supplied to the end user(s) or application. Hydrogen gas, which is formed in the cathode tank 20, is vented 26 to the atmosphere. A chlorine gas sensor 23 and a hydrogen gas sensor 38 monitor the main electrical control cabinet 27 and the immediate vicinity of the present invention; any accumulations above a threshold level are detected by the sensors and trigger an alarm cycle.
Referring now to FIG. 2, the configuration of the anode 14, the cathode 15, and the ion-selective membrane 39 is shown in more detail. Although other suitable equivalent materials may be utilized, the anode 14 is preferably comprised of a dimensionally stable titanium mesh screen welded to a copper bar coated in titanium. Although other suitable equivalent materials may be utilized, the cathode 15 is preferably comprised of a stainless steel mesh screen welded to a copper bar coated in stainless steel. The anode 14 and the cathode 15 are preferentially substantially the same diameter as the compartment to which they are mounted.
The anode 14 and the cathode 15 are preferentially mounted within the flanges 40 and 41 at a right angle to the cell walls, and are substantially in close proximity to each other with the ion-selective membrane 39 located between them. The two electrodes and the ion-selective membrane 39 are preferentially mounted so as to be parallel to each other, although it will be understood by those skilled in the art that other configurations may be utilized. Electrode and ion-selective membrane 39 spacing, in general, is well known to those skilled in the art. In a preferred embodiment, the anode 14 and the cathode 15 are positioned in close proximity to each other, and preferentially positioned in the range of 1.0 to 0.25 inches with the ion-selective membrane 39 centered between the anode 14 and cathode 15 electrodes.
The ion-selective membrane 39 is positioned between the anode 14 and the cathode 15 and an adhesive sealant is applied wherever the ion-selective membrane 39 touches the substantially square flange 40 in order to make a liquid tight seal between the anode tank 13 and the cathode tank 20. The ion-selective membrane 39 serves to prevent the flow of certain ions from one electrode to the other as described below.
Although other equivalents exist for the material comprising the ion-selective membrane 39, the ion-selective membrane 39 preferentially comprises a perfluorsulfonic acid cation exchange ion-selective membrane 39 that permits sodium ions to travel from the anode tank 13 to the cathode tank 20, but restricts the flow of negatively charged ions across the ion-selective membrane 39. A common material available for the construction of the ion-selective membrane 39 is a polytetrafluoroethylene fiber known as a Nafion N-324. This arrangement allows chloride ions to be substantially isolated within the anode tank 13, where they accumulate and concentrate to produce chlorine gas. The resulting chlorine gas effervesces out of the electrolyte solution due to its low density, and, as shown in FIG. 1, the chlorine gas is removed from the generator and added to the drinking water supply by negative air pressure produced when the source water 16 flows through the venturi injector 42. The resulting chlorinated water 44 can now be used for its intended application.
To increase the amount of chlorine to be produced for particular applications, the present invention may be ‘ganged’ or grouped together; the design disclosed herein is the preferred means of achieving large amounts of chlorine gas for treatment of large volumes of water. The rectangular shaped assemblage as described herein preferentially provides a design that serves to substantially foster the accumulation of the most concentrated brine (i.e. the brine with the highest salt concentration) at or near the bottom of the anode tank 13 and, therefore, in substantially constant contact with the electrode as the brine undergoing electrolysis is depleted and fresh brine is added. This design applies equally to the cathode 15 side of the cell, wherein the most concentrated caustic solution accumulates at or near the bottom of the cathode tank 20.
Referring now to FIG. 3, the main electrical control cabinet 27 comprises a group of common primary components: a direct current power supply 67, a logic controller 68, a human-machine interface panel 54, and a chlorine and hydrogen gas detector 69. The main electrical control cabinet 27 also preferentially comprises the following manual operator controls: a brine pump selector switch 59 which comprises three positions: manual, off, and automatic; a solenoid switch 60 which comprises three positions: manual, off, and automatic; a cooling pump selector switch 61 which comprises three positions: manual, off, and automatic; a brine tank selector switch 62 which comprises three positions: manual, off, and automatic; and a main disconnect switch 66. The main electrical control cabinet 27 serves to monitor and control the amount of chlorine gas produced by the generator. The logic controller 68 is programmable; commonly available commercial controllers are utilized in the present invention and are well known in the art. The logic controller 68 is electrically connected and provides control signal voltage to the system, and the logic controller 68 also receives feedback information from the sensors utilized to monitor system operation and safety concerns, such as gas leaks.
The control signal voltage to the brine pump 9 and the cooling pump 6 may be set at the brine pump selector switch 59 and the cooling pump selector switch 61, respectively. The flow rate sensors 7 and 21 (FIGS. 1 and 2), temperature and temperature/conductivity sensors 12 and 19 (FIGS. 1 and 2) provide feedback signals to the logic controller 68. The chlorine gas sensor 23 (FIGS. 1 and 2) and the hydrogen gas sensor 38 (FIGS. 1 and 2) provide detection signals to the chlorine and hydrogen gas detector 69.
A preferred method of operation includes the following procedures. Initial startup is accomplished by energizing the main disconnect switch 66 on the main electrical control cabinet 27. The solenoid switch 60 is turned to the “manual” operation position, and the cathode tank 20 is filled with mineral free potable water 3. The solenoid switch 60, in the “manual” operation position, provides uninterrupted power to the solenoid valve 22. Sodium hydroxide or other suitable equivalent is manually added generally in the flake form, (but other forms of sodium hydroxide may be utilized and still fall within the scope and spirit of the present invention) to the cathode tank 20, and the concentration of sodium hydroxide, as measured by a temperature/conductivity sensor 19 is monitored on the human-machine interface panel 54 until the monitor indicates a twelve percent concentration of sodium hydroxide.
The brine pump selector switch 59 is switched to manual in order to energize the brine pump 9; in the manual position, the brine pump selector switch 59 provides uninterrupted power to the brine pump 9. This causes the anode tank 13 to be filled with brine from the brine tank 4. Once the operator determines that the anode tank 13 is substantially full the brine pump selector switch 59 is switched to the automatic position. The brine concentration may be from fifteen percent to twenty five percent, and is preferentially maintained between nineteen and twenty percent. The brine concentration is monitored by the logic controller 68 via signal returns from the temperature/conductivity sensor 12; in the event that the brine concentration drops below nineteen percent as measured by the temperature/conductivity sensor 12, the logic controller 68 causes brine to be added to the anode tank 13 by energizing the brine pump 9 in order to maintain the brine concentration preferentially at or above twenty percent.
The amount of chlorine desired to be produced is controlled by the logic controller 68 based either on a preset value entered in the human-machine interface panel 54, or upon an input signal from a remote monitor. The amount of chlorine desired to be produced will vary from application to application, and may be adjusted as necessary by varying the preset value entered in the human-machine interface panel 54.
The generation of chlorine gas is begun at this point by energizing the start push button 64, and the logic controller 68 applies a positive voltage to the anode 14 and a negative voltage to the cathode 15. It will be understood that the voltage applied to and the current across the anode 14 and the cathode 15 may vary depending upon the application and the desired rate of chlorine gas generation, and deviation from the preferred conditions herein will not exceed the scope of the invention as disclosed herein. Experimental use has shown that, under the preferred conditions set forth herein, approximately sixteen amperes of electrical current across the anode 14 and the cathode 15 produces approximately one pound of chlorine in a twenty four hour period.
Chlorine gas generated by the present invention is drawn from the withdrawal port 25 by operation of the venturi injector 42. During operation of the device, the logic controller 68 monitors the flow rate sensor 7. If the source water 16 flow decreases below an acceptable minimum or ceases altogether, the decrease or loss of flow is detected by the flow rate sensor 7, the logic controller 68 causes the process of chlorine generation to stop, and the logic controller 68 causes an alarm light 52 and buzzer 53 located on the main electrical control cabinet 27 to activate, warning the operator that the source water 16 flow has fallen below a desired minimum or has stopped.
The logic controller 68 also monitors the temperature of the anode tank 13 via the temperature/conductivity sensor 12, and the temperature of the cathode tank 20 via the temperature/conductivity sensor 19. It will be understood by those skilled in the art that the present invention may generate a desired amount of chlorine gas at a range of operating temperatures within the anode tank 13 and the cathode tank 20. Under the preferred conditions set forth herein, the temperature of the anode tank 13 and the cathode tank 20 are preferentially maintained between one hundred ten and one hundred fifteen degrees Fahrenheit. The logic controller 68 cycles the cooling pump 6 on and off as required to maintain the desired temperature range. In the event that the temperature meets or exceeds one hundred twenty degrees Fahrenheit, the logic controller 68 causes the process to stop by stopping operation of the cooling pump 6, and causes an alarm light 52 and buzzer 53 located on the main electrical control cabinet 27 to activate, warning the operator that the temperature has exceeded operating parameters. Should a temperature differential between the anode tank 13 and the cathode tank 20 be desired, or should a temperature differential between the temperature of the source water 16 and that supplied to the anode tank 13 and/or the cathode tank 20 be desired, it will be understood by those skilled in the art that commonly understood means for heating or cooling the source water 16 may be provided for.
If the hydrogen gas sensor 38 or the chlorine gas sensor 23 detects a preset maximum amount of either gas, the chlorine and hydrogen gas detector 69 located in the main electrical control cabinet 27, sends a signal to the logic controller 68. The logic controller 68 causes the chlorine generation process to stop and causes an alarm light 52 and buzzer 53 located on the main electrical control cabinet 27 to activate, warning the operator of the presence of the gases. For safety reasons, the detection limits for chlorine and hydrogen gas are preferentially set at a minimum or zero level.
The logic controller 68 monitors the output of the direct current power supply 67 and preferentially causes an increase or decrease of the direct current power supply 67 to the anode 14 and the cathode 15 in order to maintain the desired rate of chlorine production.
During operation of the device, sodium hydroxide production in the cathode tank 20 is monitored by the temperature/conductivity sensor 19, and as sodium hydroxide concentration exceeds a desired concentration, the logic controller 68 causes water to be added to the cathode tank 20 via the solenoid valve 22 in order to maintain the concentration of the sodium hydroxide at the desired level. Experimental use has shown that, under the preferred conditions set forth herein, the sodium hydroxide concentration is preferentially maintained at approximately twelve percent. Also during operation of the device, hydrogen gas is generated within in the cathode tank 20. Because hydrogen gas is less dense than air and there is a small positive pressure within the cathode tank 20, hydrogen gas generated during operation of the device is vented out through a withdrawal port 26. A flow rate sensor 21 creates a signal that is sent to the logic controller 68; this signal is utilized by the logic controller 68 in calculating the amount of chlorine gas being produced. The logic controller 68 uses a custom software program FIG. 5 in order to have total operational control of the chlorine gas generator.
Referring now to FIG. 4, a first flow chart of a logic controller 68 software program for the present invention is shown. Once the system is started by the operator, the sensing and logic controller 68 runs a series of checks for satisfactory operational parameters these checks include: a determination of anode tank liquid level 71, cathode tank liquid level 73, chlorine gas detection 74, hydrogen gas detection 75, anode tank electrolyte temperature 76, and cathode tank electrolyte temperature 77. In each case, if the sensor and logic controller 68 detects one or more deviations from a desired value or range, the sensor and logic controller 68 triggers an alarm and performs a system shutdown 72. If the sensor and logic controller 68 determines that all those parameters are within operational limits, the sensing and logic controller 68 then continues testing 86 (FIG. 6) operational parameters for: heat sink one temperature 79, heat sink two temperature 80, heat sink three temperature 81, enclosure temperature 82, and venturi injector flow rate 83. In each case, if the sensor and logic controller 68 detects one or more deviations from a desired value or range, the sensor and logic controller 68 triggers an alarm and performs a system shutdown 72. Once the system parameters are tested, the sensor and logic controller 68 begins system start 84. A system stop 85 may still be performed either manually by the operator or as a result of another fault, error, power loss, parameter deviation, etc.
Once a system start 84 has been cleared for startup 86 by the sensor and logic controller 68 and/or the operator, the system prompts the operator (referring now to FIG. 6) to provide a chlorine set point 87. The chlorine set point 87 will be determined by the operator based upon the operational chlorine output desired; i.e., the chlorine set point 87 is based upon parameters well understood by those skilled in the art for determining desired chlorine treatment concentrations in light of flow rate, water volume, ambient pressure and temperature and the like. The chlorine set point 87 may be increased 88 or decreased 89 by the operator through human interface devices. Once the chlorine set point 87 has been entered, the sensor and logic controller 68 electrically signals the power controller 91 to provide 92 direct current (DC) power at the desired voltage and current to the anode 14 and cathode 15. The sensor and logic controller 68 monitors 93 the anode tank 13 electrolyte concentration via the anode tank 13 temperature/conductivity sensor 12 to determine if the anode tank 13 electrolyte concentration falls below a desired operational minimum. In accordance with the embodiment disclosed herein, the anode tank 13 electrolyte concentration preferably should not fall below 21% by volume. Should the sensor and logic controller 68 determine that the anode tank 13 electrolyte concentration has fallen below a desired operational minimum, the sensor and logic controller 68 signals 94 to add brine solution to the anode tank 13 by energizing the brine pump 9. Once the sensor and logic controller 68 determines that the anode tank 13 electrolyte concentration is at or above the desired concentration, the system continues 95 to monitor and adjust system parameters to keep the chlorine gas generation within the desired operational limits.
The sensor and logic controller 68 provides anode tank 13 electrolyte temperature monitoring 96 via the anode tank 13 temperature/conductivity sensor 12. In accordance with the embodiment disclosed herein, the anode tank 13 temperature should not rise above one hundred fourteen degrees Fahrenheit. Should the sensor and logic controller 68 determine that the anode tank 13 electrolyte temperature has risen above a desired operational maximum, the sensor and logic controller 68 turns on 97 the cooling system, providing cooling water circulation by energizing the cooling pump 6, until the anode tank 13 electrolyte temperature is within operational limits, at which point the sensor and logic controller 68 de-energizes the cooling pump 6; however, the sensor and logic controller 68 also monitors 101 the cathode tank 20 temperature, and should the cathode tank 20 electrolyte temperature exceed a desired operational maximum, the sensor and logic controller 68 will turn on 102 the cooling system. In accordance with the embodiment disclosed herein, the cathode tank 20 temperature should not rise above one hundred fourteen degrees Fahrenheit. Although the preferred embodiment disclosed herein provides a cooling system that simultaneously provides cooling water flow through the anode tank 13 and the cathode tank 20 via a closed system, it will be understood that a cooling system may be provided for that cools the anode tank 13 and the cathode tank 20 individually without deviation from the scope and intention of this invention.
The sensor and logic controller 68 also monitors 98 the cathode tank 20 electrolyte concentration via the cathode tank 20 temperature and temperature/conductivity sensor 19. Should the sensor and logic controller 68 determine that the cathode tank 20 electrolyte concentration has exceeded the desired operational maximum, the sensor and logic controller 68 energizes the solenoid valve 22 to allow mineral free potable water 3 to flow into the cathode tank 20. The amount of chlorine gas produced is determined 100 by the system.
It will be obvious to those skilled in the art that there are variations of design and configuration of the present invention that will still fall within the scope and spirit of the invention as disclosed herein. For example, the electrolysis apparatus may further comprise sources of addition of brine for electrolysis, additional or modified cooling sources, various known mechanical devices and other methods for the removal of gases, and standard equipment well known in the art of designing, constructing and operating standard electrolysis structures.

Claims

1. An improved apparatus for the generation of chlorine by means of an electrolysis unit, the improvement comprising:

An electrolytic cell comprising an anode portion and a cathode portion, the anode portion containing an anode and the cathode portion containing a cathode;

Means for separating the anode portion of the electrolytic cell from the cathode portion of the electrolytic cell;

Means for providing brine solution to the anode portion of the electrolytic cell;

Means for providing make-up water to the cathode portion of the electrolytic cell;

Means for removing chlorine gas from the electrolytic cell;

Means for removing hydrogen gas from the electrolytic cell;

Measuring means to measure temperature and conductivity within the electrolytic cell; and

Controlling means for controlling operation of the electrolytic cell.

2. The apparatus of claim 1 wherein the apparatus further comprises means for cooling the electrolytic cell.

3. The apparatus of claim 1 wherein the measuring means comprises one or more combination temperature/conductivity sensors.

4. The apparatus of claim 1 wherein the electrolytic cell is comprised of an anode tank and a cathode tank, the means for separating the anode portion from the cathode portion is an ion-selective membrane, and the anode and cathode are located adjacent to the ion-selective membrane.

5. The apparatus of claim 4 wherein the anode tank and the cathode tank each further comprise a drain valve and an overflow port.

6. The apparatus of claim 1 wherein the means for providing brine solution to the anode portion of the electrolytic cell comprises a brine tank with supply water input and brine water output, the brine water output connected to the anode portion of the electrolytic cell through a brine water pump and a brine solution feedline, and the brine water pump is electrically controlled by the controlling means.

7. The apparatus of claim 1 wherein the means for providing make-up water to the cathode portion of the electrolytic cell comprises a mineral tank, a flow rate sensor, a solenoid valve and a make-up water feedline connected to the cathode portion of the electrolytic cell.

8. The apparatus of claim 1 wherein the means for removing chlorine gas from the electrolytic cell further comprises water supply chlorine gas introduction means.

9. The apparatus of claim 8 wherein the water supply chlorine gas introduction means comprises in-line gas injection means.

10. The apparatus of claim 10 wherein the anode and cathode are located parallel to and within a range of 1.0 to 0.25 inches from the ion-selective membrane.

11. The apparatus of claim 1 wherein the means for removing hydrogen gas from the electrolytic cell comprises means to vent hydrogen gas to the atmosphere.

12. The apparatus of claim 1 wherein the controlling means for controlling operation of the electrolytic cell is comprised of a main electrical control cabinet, the main electrical control cabinet comprising a programmable logic controller, a low voltage direct current power device, an alternating current power supply, and a human interface means electrically connected to the logic controller.

13. The apparatus of claim 13 wherein the controlling means provides voltage across an anode and a cathode located within the electrolytic cell.

14. The apparatus of claim 4 wherein the ion-selective membrane is disposed in said connecting means between said anode tank and said cathode tank, the ion-selective membrane separating the anode tank interior from the cathode tank interior.

15. The apparatus of claim 1 further comprising cooling means disposed within the anode portion and the cathode portion, the cooling means comprising a water cooling system comprising cooling water feedlines within the electrolytic cell and means for supplying the cooling system with cooling water from a water source.

16. The improvement of claim 4 wherein the anode tank and the cathode tank can have different geometric shapes.

17. The apparatus of claim 1 wherein the separation means is comprised of a polytetrafluoroethylene fiber ion-selective membrane.

18. An apparatus for producing an output solution having a predetermined level of available free chlorine comprising:

A main electrical control cabinet comprising a logic controller, a low voltage direct current power device, an alternating current power supply, and human interface means electrically connected to the logic controller;

An anode tank containing an anode and a cathode tank containing a cathode, the anode tank and cathode tank further comprising flanges connecting the interior portion of the anode tank with interior portion of the cathode tank;

An ion-selective membrane located within the junction of the anode tank flange and the cathode tank flange, the anode tank and cathode tank containing one or more temperature sensors located within the anode tank and the cathode tank, the anode tanks and cathode tank containing one or more conductivity sensors located within the anode tank and cathode tank;

A brine tank, brine solution feed line connected to the brine tank and the anode tank, and a brine pump disposed within the brine feed line;

A make-up water supply comprising a mineral tank, flow rate sensor, solenoid valve and make-up water feedline connected to the cathode tank;

A low voltage direct current device electrically connected to the anode and the cathode;

A potable water source comprising a source water input, a chlorinated water output, a potable water pump electrically connected to the alternating current power supply, logic controller and a venturi valve for injecting gas removed from the anode tank into a water supply;

Means for removing chlorine gas from said anode tank, the means for removing chlorine gas connected to a venturi valve disposed within the potable water supply tubes;

Means for removing hydrogen gas from said cathode tank;

A drain valve located proximally to the bottom of the anode tank and a drain valve located proximally to the bottom of the cathode tank;

Overflow discharge means located in the anode tank and overflow discharge means located in the cathode tank;

Cooling means comprising a cooling tube running into and out of the interior of the anode tank and cathode tank, a cooling water pump, one or more cooling tubes located in the interior of the anode tank and the cathode tank, and cooling tube return connected to the potable water source;

A logic controller electrically connected to the low voltage direct current device, the one or more temperature sensors, the one or more conductivity sensors, the brine pump, the flow rate sensor, the solenoid valve, and the cooling water pump;

A hydrogen gas sensor electrically connected to the logic controller;

A chlorine gas sensor electrically connected to the logic controller.

19. The apparatus of claim 18 wherein the anode and the cathode are located proximal to and substantially parallel to the ion-selective membrane.

20. An method for producing an output solution having a predetermined level of available free chlorine, the method comprising:

Providing a main electrical control cabinet comprising a logic controller, a low voltage direct current power device, an alternating current power supply, and human interface means electrically connected to the logic controller;

Providing an anode tank containing an anode and a cathode tank containing a cathode, the anode tank and cathode tank further comprising flanges connecting the interior portion of the anode tank with interior portion of the cathode tank;

A brine tank, brine feed line connected to the brine tank and the anode tank, and a brine pump disposed within the brine feed line;

Means for removing hydrogen gas from said cathode tank;

A hydrogen gas sensor electrically connected to the logic controller;

A chlorine gas sensor electrically connected to the logic controller.

21. The method of claim 20 wherein the anode and the cathode are located proximally and substantially parallel to the ion-selective membrane.

22. A method of producing chlorinated water, the method including the steps of:

Causing a brine tank to filled with a brine solution;

Causing an anode tank to be filled with brine solution from the brine tank;

Causing a cathode tank to be filled with a caustic solution;

Providing a main electrical control cabinet, the main electrical control cabinet comprising a logic controller, a low voltage direct current power device, an alternating current power supply, and human interface means electrically connected to the logic controller;

Entering desired chlorine generation parameters into the human interface means;

Causing a voltage to be applied to an anode located within the anode tank;

Causing a voltage to be applied to a cathode located within the cathode tank;

Monitoring the brine concentration in the anode tank;

Monitoring the sodium hydroxide concentration in the cathode tank;

Withdrawing chlorine gas from the anode tank and injecting the withdrawn chlorine gas into a water supply;

Withdrawing hydrogen gas from the cathode tank;

Providing a cooling means within the anode tank and the cathode tank;

Monitoring the temperature of the brine solution in the anode tank;

Monitoring the temperature of the caustic solution in the cathode tank;

Monitoring the flow rate of supply water to be chlorinated; and

Varying the voltage applied to the anode and voltage applied to the cathode.