Classifications

• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/72—Treatment of water, waste water, or sewage by oxidation
  • C02F1/76—Treatment of water, waste water, or sewage by oxidation with halogens or compounds of halogens
  • C02F1/766—Treatment of water, waste water, or sewage by oxidation with halogens or compounds of halogens by means of halogens other than chlorine or of halogenated compounds containing halogen other than chlorine
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/50—Treatment of water, waste water, or sewage by addition or application of a germicide or by oligodynamic treatment
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/68—Treatment of water, waste water, or sewage by addition of specified substances, e.g. trace elements, for ameliorating potable water
  • C02F1/685—Devices for dosing the additives
  • C02F1/688—Devices in which the water progressively dissolves a solid compound
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
  • C02F2103/02—Non-contaminated water, e.g. for industrial water supply
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
  • C02F2103/02—Non-contaminated water, e.g. for industrial water supply
  • C02F2103/023—Water in cooling circuits
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2303/00—Specific treatment goals
  • C02F2303/04—Disinfection
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S210/00—Liquid purification or separation
  • Y10S210/931—Zebra mussel mitigation or treatment

Definitions

• This invention relates to the treatment of water by iodine species, particularly the disinfection of water for use as a drinking source for farm animals, in agriculture, fisheries, the food industry, fruit and vegetable, industrial water treatment systems and pharmaceutical industries.
• the invention also relates to the preservation of foodstuffs, particularly foodstuffs such as fish, meat, fish and meat products, and fruit and vegetables susceptible to bacterial spoilage, with iodinated ice.
• Iodine has been used for water disinfection on a large scale in the past. Iodine is used commonly also for its antibiotic (sensu stricto) effects against bacteria, viruses and cysts, as these three pathogens constitute the most common health risks in maintaining biologically safe water supplies. Traditionally, crystalline iodine is dissolved in water under static conditions by the addition of small amounts of KI, which greatly enhances the dissolution of the iodine.
• iodine is generally provided from an iodophor source or as an aqueous solution by the use of KI to aid the dissolution of iodine. Most treatments employ pHs lower or higher than about 9.
• iodine hydrolyzes in aqueous solutions to form hypoiodous acid, HOI, in amounts proportional to the pH of the solution, wherein above pH 8.5, iodine is present almost exclusively as HOI. Both dissolved I 2 and HOI possess antipathogenic properties. At pHs 5-7, iodine, as I 2 , exhibits antibacterial action and at higher pHs, e.g. 7-10, HOI is an efficient virucide.
• Chang (1) reports that above pH 8, HOI decomposes slowly to form iodide and iodate ions, especially in the presence of dissolved iodides. Neither iodides nor iodates have been found to be germicidal. Further, I " reacts with I 2 to form the highly coloured I 3 " ion, which is also ineffectual as a germicide.
• iodine may be generated upon dissolving the solid in organic liquids such as ethanol, acetone, diethyl ether, toluene, p-xylene, benzene and carbon disulphide.
• organic preparations of iodine may be generated by reacting appropriate organics with iodine, e.g., iodoform, methylene iodide.
• iodine e.g., iodoform, methylene iodide.
• PVP-iodines, iodoforms and povidone-iodine preparations are used as detergents and antiseptics.
• iodophors Most of these compounds exhibit germicidal action upon dilution in water, whereupon the iodine is hydrated and released into the water, usually as molecular iodine. Many biocidal, organic iodine compounds are commonly referred to as iodophors.
• iodine-bearing resins are made by attaching I 2 , tri-, penta- and hepta-iodide ions to quaternary ammonium, styrene-divinyl benzene, cross-linked anion- exchange resins. Upon elution with water, the polyiodides and iodine are released from the resin via anion-exchange mechanisms.
• Disinfection of drinking water for farm animals, particularly, chickens and pigs raised under confined conditions represents a major problem owing to the contamination of the water throughout the entire distribution systems by common bacteria present in animal feces, such as E coli, other fecal coliforms and fecal streptococci. Both pigs and chickens spread the bacteria found in manure from barn floors to drinking vessels, which, in turn, leads to back-contamination of the entire water distribution infrastructure network and allows infection to spread from barn to barn. Further, seasonal variations in source- water bacterial levels have been found to contribute to infection of livestock.
• CHLORINE highly unstable with respect to composition of individual batch lots causes fatality if dosage exceeds 10 - 12 ppm gases off at higher temperatures to generate toxic aerosols - reacts with naturally occurring acids to form toxic by-products, for example, tri- halomethanes very sensitive to changes in pH and temperature and is only effective in narrow pH and temperature ranges moderately-to-highly corrosive depending on its concentration and chemical specification to damage distribution equipment and requires special handling requires careful pre-mixing, before distribution to livestock very high maintenance costs for distribution system, and liberates free chlorine gas upon exposure to most metals.
• IODOPHORS high levels of phosphoric acid in most commercially available products causes burning of avian digestive tract which results in weight loss and/or fatality, as well as damage to metals and rubber seals within the distribution networks much more expensive than chlorine products owing to preparation and shipping costs - sensitive to exposure to light and also photo-degradable biologically active only when mixed with water, if permitted to remain in prolonged storage, undiluted iodophor may develop infection by Pseudomonas spp.
• the invention provides in its broadest aspect a method for producing bacteria-free iodine species-containing drinking water for farm animals under continuous dynamic water flow, comprising
• iodine-species as used in this specification is meant, collectively, dissolved molecular iodine and hypoiodous acid species present within the pH range 5-8.
• the ppm concentrations herein refer to the concentrations of these species determined as free molecular iodine.
• iodinated-ice in this specification and claims means a mixture of ice containing iodinated species, optionally, with acceptable amounts of water as to not cause total melting of the ice to permit any temperature increase.
• the iodinated ice is potassium iodide free.
• the iodinated ice of use in the practice of the present invention is made most preferably by dissolution of USP grade, flake crystalline iodine into water without the presence of potassium iodide or other solubilizing compounds.
• the method as hereinabove defined comprises
• the first water flow runs from and is subsequently returned after passing through the iodination system to the second (main) water flow as to constitute a loop network.
• the first flow constitutes a water feed line not led off the main flow wherein feed water to an iodine generator is fed from a distinct water source, having a first flow rate controlled by an independent valve. After passing through the iodine generator assembly it is blended with the main flow as hereinabove defined.
• the invention provides a dynamic water flow process for providing bacterium-free, iodine species-containing drinking water for livestock at constant, safe, efficacious bacterial levels.
• the process of the invention provides a means of maintaining the constant iodine species levels in the drinking water by adding the selected amount of saturated iodine species solution to the main flow at desired flow rates, wherein the saturated solution levels in the iodine generator are set by the selected temperature of the saturated solution. This is preferably achieved by measurement of the temperature of the iodinated solution and subsequent of the temperature to the desired pre-selected valve by heating means, in consequence of instructions from a central control system.
• the method as hereinabove defined further comprises a dynamic method further comprising (a) measuring the temperature of said first water flow by temperature measuring sensing means to determine the temperature of said first water flow; and (b) raising the temperature of said first water flow by said heating means in consequence of said temperature measurement to heat said first water flow to said pre-determined temperature.
• the method thus can readily provide a continuous dynamic flow of iodine species- containing drinking water having any desired concentration of 1-15 ppm., preferably 2-5 ppm. Volumes ranging up to 50 1. per minute can be readily provided with two iodine canisters linked in series in the generator assembly, providing up to 1 1. per minute depending on the water temperatures selected.
• the invention provides an apparatus for producing bacterium-free, iodine species-containing drinking water for farm animals under dynamic water flow comprising
• the apparatus further comprises an apparatus as hereinabove defined further comprising
• heating means for heating said first water flow; and (h) control means for receiving said temperature measurement and instructing said heating means to heat said first water flow to said pre-selected temperature in consequence of said temperature measurement
• the mixing means comprises an iodine generator having a housing containing the crystalline iodine.
• the iodine generator assembly has a plurality of individual generators, preferably two, linked in series. Each of the individual canisters preferably has means for heating the water passing therethrough, with the final canister having a temperature sensing probe which is connected to a central control.
• Table 1 shows the efficacy of elemental iodine against E coli and other enteropathogenic organisms commonly associated with livestock. E coli is effectively killed by 1-10 ppm. The Canadian government has approved the use of up to 14 ppm of
• iodine for the disinfection of drinking water for livestock.
• the LD 50 of iodine in chickens is about 625 ppm. We have demonstrated that chickens could safely consume residual iodine at concentrations of about 2 ppm.
• the system of the invention is capable of delivering pre-selected variable amounts of iodine in the very useful 1 to 15 ppm range which enables the method of the invention to be adjusted according to seasonal and other unforeseen changes in bacterial levels in the farm water distribution network.
• the present invention overcomes the bacterial problem in inherent drinking water for livestock by providing a metered amount of iodine species to the water distribution network such that: (a) the level of iodine is sufficiently high to kill the bacteria without being so high as to kill livestock, and (b) by provide the metering of the biocidally- effective levels of iodine in a safe, controlled and consistent manner.
• the present invention further provides an improved general disinfectant produced by a method as hereinabove defined for use in the following duties.
• the process and apparatus as hereinabove defined may be used to continuously produce iodine species-containing aqueous solutions of preferably up to 300 ppm iodine, for subsequent dilution to lower concentrations, generally, less than 20 ppm and preferably 2 - 10 ppm.
• the diluted solutions may be used for the following purposes, either as liquid or as frozen or partially-frozen iodine species-containing ice/water, optionally including brine compositions.
• Such diluted compositions may be used as a general disinfectant, as metered dosages of iodine, for example, for duties such as, - surface disinfectant in food processing, medical environments, dental offices; equipment disinfectant in food processing, medical environments, dental offices; hand wash in food processing, medical environments, dental offices; foot bath in processing industries; conveyor belts; - industrial/commercial cooling tower water to adequately disinfect the cooling water prior to discharge or reuse; carcass wash equipment for meat, poultry and fish with no iodine uptake into the flesh in the food processing industry, to enhance the shelf life of fresh food; fruit and vegetable wash equipment whereby the disinfection of fruits and vegetables prior to shipping for local or export markets is necessary in most countries around the world; close loop water recirculation systems in vehicle and other equipment for the transportation of live marine animals and fish and in aquaculture.
• the iodine species-containing solutions of the invention are provided in controllable specific dosages for both micro-nutrient and disinfection needs; water chemistry adjusters and post filters to supply microbially safe iodine-free drinking water and to deliver safe drinking water through disinfection and concurrently deliver iodine as a human micro-nutrient to combat Iodine Deficiency Disorder presently affecting millions of people, globally.
• iodine may, optionally, be used on a large scale in conjunction with chlorine to create a dual halogen effect for disinfecting drinking water; deliver specific metered dosages of iodine through a watering system to be used as a soil disinfectant, herbicide and to enrich iodine deficient soil, to address vegetable iodine uptake as well as microbial control in the soil; - specific metered dosages of iodine to aerosol spraying systems for misting livestock during warm weather and fruits and vegetables during transportation and presentation; to provide metered dosages of pure, elemental iodine in the manufacture of pharmaceuticals; - as an essential iodine additive to most commercial feeds to eliminate the associated costs of the carrier molecule for the iodides as presently used; for use as iodine containing disinfectant in industrial process water in cooling canals for canned fruits and vegetables and the movement of fish by means of water canals throughout a processing plant or a final rinse in a fresh fruit or vegetable wash canal; io
• Present vehicles of delivery for iodine to humans is iodized salt and for livestock animals and fish it is added to their feed as a form of iodide by the spraying or irrigation of plant for them to retain the iodine and pass it on through the food chain in iodine deficient areas of the world.
• fish In the case of fish it can be put in feed and or added to the water supply.
• the system can deliver required metered dosages for human consumption, added to livestock feed during preparation and in the water for marine life; as an egg wash wherein the movement of commercial eggs often requires disinfection of the egg, and in the case of fish a disinfectant during hatching to reduce mortality.
• the system of the invention can provide metered specific dosages of iodine to water supplies feeding all types of ice machines. Different dosages and different ice types are required in the various ice applications. There is no significant iodine uptake by fish fillets in contact with iodinated ice or the resultant melt water; - in sewage and waste water treatment.
• the invention provides iodine species-containing water prepared according to the invention as hereinabove defined for use in the aforesaid applications.
• the invention provides a method of preserving without bacterial spoilage and reducing the risk of bacterial contamination during the storage and/or transfer of foodstuff, comprising treating said foodstuff or the locus of said foodstuff with an anti-pathogenically effective amount of iodinated ice.
• the iodinated water can be frozen at controlled rates with standard ice-making machines.
• iodinated ice varies with the concentration of iodine over a range of iodine concentrations, from 10 ppm to about 240 ppm, employing a gradual freezing process, as expected, given the preference of iodine to remain in the aqueous phase as long as possible, the iodine concentration increases visibly within any given resultant cube of ice towards the centre of the cube, i.e., via the mechanism of fractional crystallization.
• a two-phase system evolves at all concentrations, except ⁇ 5 ppm.
• the overall aim of using iodinated water-ice according to the invention is to enhance the preservation of foodstuffs both by eliminating existing pathogens in the water to be frozen, and/or to kill pathogens already present on the foodstuff. It is not intended that the invention process disinfects foodstuffs via the invention process throughout the main body of the foodstuff, as this would require the uptake of iodine by the pre- harvested food resource.
• the main object is to prevent subsequent contamination and minimize pathogenic spoilage. Pathogens already present within the foodstuff are herein referred to as being "internal”, whereas pathogens contaminating the foodstuff during or after processing are referred to as being "external".
• the invention is of particular value in controlling bacteria, and in particular surficial bacteria which may be spread from lot to lot, e.g., fish to fish, during food processing procedures, or by careless handling after processing.
• bacteria normally resident in the gut of a fish and which should never reach humans under "normal" processing conditions may be spread to the exposed surfaces of the fish fillet during entrail removal.
• FIG. 1 represents a schematic flow diagram of a method and apparatus according to the invention
• Figs. 2, 3 and 4 represent schematic flow diagrams of alternative methods and apparatus according to the invention
• the same numerals denote like parts and dotted lines denote electrical connections.
• the apparatus distribution network and method embodied therein is shown generally as 2 and comprises a water feed conduit 8, which feeds inlet water through a shut-off valve 10 to a preconditioner 12.
• the incoming water is, typically, an untreated artesian source, hereinafter referred to as the "main flow" which enters the system at, typically, ambient temperature, e.g. 4 - 18°C.
• network 2 is designed to also accept water at other temperatures of between 0° - 40°C.
• Preconditioner 12 is a preferred optional feature and contingent upon the quality and chemistry of the source water and may include pre-filters, water softeners or pH adjustor media.
• Incoming main flow water after leaving preconditions 12 is preferably in the 6 - 8 pH range.
• Conduit 16 has an inner diameter approximately 1/4 to 1/8 that of main line 14 owing to the lower relative flow rates required through conduit 16. Conduit 16 and the network downstream is described hereinafter.
• the network is designed to accept incoming water pressures of between 40 psi and 100 psi such that at a minimum operating condition more than 2 1. per minute passes through main line 14 and such that the absolute pressure drop across a flow-restrictor disk 20 across line 14 will be about 2 psi.
• Flow-restrictor disk 20 is a round, 1.5 mm inch thick slice of PVC plastic which has been machined to fit into a modified plastic union. Disk 20 itself has an opening in its centre of about 6 mm., such that a pressure drop of about 2 psi is generated across the disk orifice as water passed through it.
• flow- restrictor disk 20 is a pre-set flow switch 22, which is self-activated when the flow in main line 14 exceeds 2 1. per minute.
• the preferred maximum attainable flow rate through main line 14 is about 50/1 per minute, and the minimum flow rate is slightly greater than 2 1. per minute.
• Flow switch 22, upon experiencing flow rates greater than 2 1. per minute generates an internal electrical impulse which is transmitted to a dual-action electrical solenoid valve 24, present at the back end of the iodine generator assembly described hereinbelow.
• solenoid 24 When solenoid 24 receives an impulse that the flow rate exceeds 2 1 per minute, it opens and allows saturated iodine liquor generated as hereinafter described to flow into main line flow conduit 14.
• the control system for the metering of saturated iodine solution into main line 14 is discussed hereinbelow. If the flow rate does not exceed 2 1.
• flow switch 22 does not generate the electrical impulse required to open solenoid valve 24, and solenoid 24 will remain closed. In this manner, at flow rates less than 2 1. per minute, no iodine solution passes into main line 14.
• Flow switch 22 can be set to accept any desired flow rate, and need not be restricted to 2 1 per minute.
• the purpose of having solenoid valve 24 in this particular location within the system is to prevent the leakage of any iodine into the main flow in the event the above mentioned flow condition criteria are not met, i.e. in the event that the flow within the main line does not exceed 2 1 per minute.
• solenoid valve 24 is such that, if power to the solenoid itself fails, or if the flow switch malfunctions, it will shut completely and, thus, cut off any iodine from reaching the main flow.
• a solenoid here is the best way to insure absolute control of allowing or disallowing iodine to flow from the iodine generation loop into the main flow, and therefore provides a useful safety feature, required to prevent the accidental over dosage of iodine in the event of a power failure or other related system failure.
• a check valve or solenoid Whether present in this particular configuration, or as a nonelectrical device it is desirable to place a check valve or solenoid at this location within an embodiment of the present invention.
• untreated source water is still allowed to flow to the livestock at the terminal end of conduit 14.
• Flow switch 22 only controls solenoid valve 24 and does not effect the flow of water through conduit 14.
• valve 26 After passing through filter 18, water in conduit 16 flows through an adjustable needle valve 26 which can be adjusted manually to deliver a selected variable amount of water over a given time period to iodine generator assembly 15. Typically, valve 26 is adjusted such that about 100 ml to 300 ml per minute is delivered into assembly 15 to produce an equal amount of saturated iodine liquor to be subsequently delivered into main flow 14 through solenoid valve 24. Thus, needle valve 26 controls the gross quantity of saturated iodine liquor produced within iodine generator assembly 15 and is adjusted according to the specific needs of each user, but is capable of delivering up to about 10 ppm to 12 ppm in the embodiment herein described.
• Carbon filter cartridge 28 has a PVC housing 29 and a heating element 30a, which serves, initially, to warm the incoming water before it reaches iodine reservoirs 36, 37. Heating element 30a is wound around carbon filter cartridge 28 such that the temperature of the element never reaches a temperature high enough to damage any of the plastic components it touches. The temperature of heating element 30a is regulated by a central temperature controller 32 by means of an electrical connection 31.
• Conduit 16 continues between carbon filter cartridge 28 and a first iodine generator 36 after first passing through a PVC-diaphragm one-way check valve 34, which permits flow of water through conduit 16 in the downstream direction only. Conduit 16 continues to a second iodine generator 37.
• iodine generators 36 and 38 are linked in series and each comprises a PVC canister containing crystalline iodine water-entry and liquor-exit holes (not shown) and housing 41a and 41b, respectively.
• Heating elements 30b and 30c are present in the respective housings of iodine generator 36 and 38 to further warm the water during its passage through the iodine generator 15 assembly. Heating elements 30b and 30c are also regulated by central temperature controller 32.
• iodine concentrate After passage through generator 36, the resultant iodine aqueous solution is referred to as "iodine concentrate" and proceeds through conduit 16 to second iodine generator 38 after first flowing through a sight glass 40, which comprises a clear, pressure-resistant tube and water-tight fittings, through which the concentrate may be viewed for the purpose of determining required recharge of first iodine generator 36.
• sight glass 40 When sight glass 40 reveals clear, colorless water, a new iodine recharge is placed in the housing of first iodine generator 36.
• Heating element 30c is present in second iodine generator 38 in order to further raise the temperature of the iodine concentrate to a pre-selected level.
• the temperature of the iodine concentrate is directly measured by a thermocouple 42 inserted into housing 41b and the reading sent to central temperature controller 32.
• central temperature controller 32 allows more or less current to reach each of the heating elements 30a, b, c such that the temperature of the saturated iodine concentrate leaving generator 38 at a pre-selected, desired value to provide a constant resultant concentration of outgoing "saturated iodine liquor".
• Central temperature controller 32 is capable of being programmed to accept a wide range of temperature set points, as would be determined for each application.
• the housings are made of iodine resistant PVC, as are the iodine recharges or holders. Water is, preferably, made to flow through the iodine charges from bottom to top to insure maximum dissolution rates of the iodine.
• the saturated iodine liquor flows through conduit 16 and solenoid valve 24, provided that the flow rate through conduit 14 criterion described hereinabove is met. It is blended back into main line conduit 14 at iodine injection port 44. As such, the "iodinated main flow” now flows through conduit 14, past a shut-off valve 46 and into a water distribution network shown generally as 50 in a given poultry or swine barn, where it is then consumed by the livestock from whichever type of drinker the farm uses. Any excess water passing through the network may be run off to drain.
• Artesian water is fed through inlet conduit 8 past shut-off valve 10 through preconditioner 12 at a flow rate of not less than 2 1. per minute and not more than about 50 1. per minute preferably on average about 10 1. per minute at a pH 6 - 8, temperature 4 - 6°C and pressure of 60 psi.
• Main flow water passes through conduit 14 where some of the main flow is diverted to iodine generator assembly 15 through conduit 16 at a flow rate of about 200 ml/minute. The rest of the main flow flows through flow restrictor disk 20 such that an absolute pressure drop of about 2 psi is generated across flow restrictor disk 20.
• Flow restrictor 20 governs the rate of flow of diverted main flow which ultimately reaches iodine generator assembly 15.
• the main flow now proceeds through flow switch 22, such that, at a pre-set flow rate exceeding 2 1 per minute, the flow switch 22 generates an electrical impulse which is fed to dual action solenoid valve 24.
• Such an impulse is continuous and causes solenoid valve 24 to open and remain so, as long as the flow rate is maintained above 2 1 per minute.
• the rest of the main flow continues through conduit 14 uninterrupted until iodine liquor is blended back into the main flow at iodine species liquor injection port 44.
• the diverted flow derived from conduit 14 passes into conduit 16 owing to the pressure drop induced by flow restrictor disk 20 and passes through filter 18 to remove any large particulate matter before flowing through adjustable needle valve 26.
• Controller 32 is pre-set to a given temperature, such that, by the time the iodine liquor emerges from the final iodine generator 38 it has achieved the same temperature as the pre-set set point programmed into the central temperature controller 32, for example, 28°C.
• Filtered water passes through one-way PVC-diaphragm check valve 34, which prevents back-flow of any iodine concentrate or liquor generated downstream, and enters first iodine generator 36, where it is heated by second heading element 30b to a temperature of about 20°C before passing through the actual crystalline iodine held within generator 36.
• Elemental iodine in generator 36 has a mass of about 1.0 kg, and is present as USP-Grade, solid flakes.
• the iodine species concentrate has a concentration of about 200-240 ppm at this stage.
• the iodine concentrate After leaving first iodine generator 36, the iodine concentrate passes through sight glass 38 and enters second iodine generator 38, where it is heated to the pre-set temperature of about 28°C before passing through an additional 1.0 kg of crystalline iodine held in iodine generator 38 wherein the resultant iodine liquor has a concentration of about 280-320 ppm.
• Thermocouple 42 senses the temperature of the iodine concentrate and the resultant signal is sent to controller 32, which in turn determines if the temperature of the iodine concentrate is at the pre-set set point, and causes the heating elements 30a, b, c to put out more heat if the temperature is too low, or to cycle on-and- off to maintain the status quo; at no time does controller 32 cause the concentrate to exceed the pre-set set point value.
• iodine liquor concentrate is blended back through conduit 16 into the main flow at iodine injection port 44 at an appropriate rate as determined by adjustable needle valve 26 as to generate sufficient aqueous iodine species for the production of a pre-selected final concentration of about 2 ppm to 3 ppm of free iodine in the blended main flow.
• the blended main flow proceeds past shut-off valve 46 through conduit 14 and is allowed to flow into various drinking vessels of farm water distribution network 50 to be consumed by livestock, particularly, chickens and pigs, such that a free residual of iodine is present to the end of the water distribution network of drinkers. This ensures disinfection along the entire distribution network and that the livestock can consume the desired level of iodine.
• the solubility of crystalline iodine in water is directly proportional to the temperature of the water. To achieve the desired pre-selected level of iodine species concentration, accurate temperature control and flow rates of the water leaving the iodine generator assembly is required.
• thermocouple temperature sensor is most preferably located within the final iodine generator.
• desired temperature tolerances are so fine that if the sensor is placed in any other location in the water flow, the concentration of iodine is lower than ideal because the water within the generators warms up by several degrees in consequence of the ambient heat acting on the generators and given that water within the generators flows at relatively low flow rates
• the temperature within the barn environment is subject to relatively large fluctuations based on the season and the heat produced by the livestock themselves, such that the ambient temperature within the barn might reach 27° to 30°C in the summer and to less than 10°C in the winter.
• One preferred embodiment of the present invention uses a manually controlled needle valve to adjust the amount of iodine concentrate added to the main flow, which needle valve has a preset setting related to the desired pre-set and constant temperature of the iodine concentrate leaving the generator assembly.
• a preferred aspect of the present invention provides a method which effectively eliminates temperature as a difficult-to-control variable, by maintaining the temperature of the iodine concentrate constant at a pre-selected value.
• This is preferably effected by the use of heating elements inserted directly into the generator or assembly.
• water emerging from the generator assembly is at a constant temperature of, say, about 28°C. Therefore, the concentration of iodine is maintained constant and at a saturated level, regardless of the temperature of either incoming main water flow or of temperature fluctuations within the barn/installation environment itself.
• use of a thermocouple inserted in the generator assembly to monitor the temperature of the iodine concentrate, and to control the heaters using a feedback loop embedded in the central temperature controller provides the desired control.
• the central temperature controller is a commercially available device distributed by Watlow Ltd. and comprises a plastic body housing several computer components programmed to accept ranges of set point values and PID control loops.
• the controller is equipped with fail-safe features, including the ability to lock-out any unwanted adjustment, such that inadvertant changes are impossible to make
• a preferred embodiment of the invention involves the flow of a portion of the main water into the minor secondary line originating from the main line via hydraulically coupling the two lines, i.e. by causing a pressure drop to exist at some point between the places where the secondary line departs the main line and the place where the secondary line rejoins the main line from the main line itself, some water is made to flow into the secondary line in a controlled fashion, such that the rate of flow is proportional to the pressure drop induced across the coupling and to the size of any restricting aperture, therefore, which exits within the main line to cause the pressure drop.
• the pressure drop and subsequent flow rates depend upon the relative diameters of the main and secondary lines, respectively.
• a "shunt" ball valve having internal seal-rings can control the amount of back-pressure generated within the main line to control the amount of water able to flow through the iodine generators.
• a pressure drop of about 2 psi is generally required to achieve the hydraulic coupling of the iodine generators to the main line, i.e. at pressure drops across the main line of less than 2 psi, no appreciable iodine is generated.
• the valve aperture in the "shunt valve” used to effect the pressure drop is subject to expansion and contraction owing to temperature changes of both the surrounding atmosphere and the water in the main line. These physical changes in the apertures may cause small but significant changes in the pressure drop across the shunt valve, and therefore change the amount of iodine produced by the iodine generators.
• a union formed of a plastics material to hold a machined shunt disk having a specific aperture width, determined by trial and error, to produce the desired pressure drop significantly reduces variable pressure drops across the system.
• a PVC- diaphragm check value is inserted preferably between the main flow and iodine generator assembly.
• an electrical dual-action solenoid activated by a flow switch incorporated into the main-line flow is able to effectively stop migration of iodine into the main line under conditions of no- flow, because it acts under the influence of a signal from the flow switch to be either fully open, regardless of back pressure (the minimum flow criterion notwithstanding) or to be fully closed. Therefore seepage of iodine by diffusion is not an issue, as with the PVC-diaphragm check valve alone.
• a plurality of iodine cartridges most preferably two canisters in the generator assembly are used.
• the length of the iodine cartridge and the mass of iodine contained therein is generally important for the ready generation of saturated iodine liquor at the selected temperature levels.
• a particle/chemical removal filter is installed ahead of the crystals, such that the flow-restriction characteristics of the filter has minimal effect on the pressure drops across the iodine generator.
• Two iodine generators are preferably used instead of one, because in only using one generator, a risk exists of not generating sufficiently high concentrations of iodine in the liquor.
• the first generator serves to provide the bulk of the iodine concentrate, whereas the second iodine generator provides any small increment of iodine needed to achieve saturation of the liquor, as well as serving as a backup for the first generator as the iodine in the first generator is consumed.
• the incoming water flows from the bottom of the cartridge through to the top in contrast to commercial cartridges, which operate in an opposite manner. This modification enhances the dissolution of the crystalline iodine and allows the production of an iodine-saturated concentrate on a consistent basis, without having to worry about consistency of batch lots of chemicals, as is the case with using iodophors or hypochlorite solutions.
• FIG. 2 shows an alternative embodiment wherein water is fed to line 16 from external water line 8a, through shut-off valve 10a.
• Figs. 3 and 4 are analogous to Figs. 1 and 2 but wherein water fed through conduit 16 is pre-heated to a pre-determined temperature prior to entering the iodine generator assembly 15, by means of water heater 9.
• this shows an off-shoot conduit 60 having a flow control valve 62 and which feeds diluted iodine species-containing water to a fish pond or other aquatic farm holding system 64.
• conduit 60 As an off-shoot from conduit 60 is a side conduit 66 leading to a holding tank 68 from which the iodinated water is fed through valve 70 for transportation for use in duties as a disinfectant or iodine nutritional source as hereinabove described, e.g. a container 72 holding an ice/iodinated water slurry 74 to preserve fish 76.
• a container 72 holding an ice/iodinated water slurry 74 to preserve fish 76.
• the present iodinated ice invention provides two main practical embodiments, viz. (a) iodinated ice as a reservoir for iodine for disinfection in the short term, e.g trawler cargo holds, and in the longer term, e.g. for foodstuff preservation during transport/awaiting sale; and (b) using iodine for pre-consumption disinfection of water to be used as ice with an intention of using the ice per se as a disinfectant agent.
• These two embodiments although subtly different are distinct in that - 1. the concentration of iodine required for each application is different;
• the pH adjustment mechanism, degree and timing of pH adjustment of water to be iodinated and subsequently frozen vary depending upon whether only the water to be frozen needs to be disinfected before use and not retain sufficient iodine so as to be biocidal, as in case (b) hereinabove, or whether the ice per se is intended to release iodine at biocidally significant concentrations and pHs, i.e., the ice itself must be frozen such that it retains the iodine at a given pH;
• the mechanism and rates of freezing is, preferably, carefully controlled in case (a) above, and not necessarily so for case "b", owing to the possible loss of iodine due to gassing off or re-precipitation from solution at surrounding ambient temperatures;
• “regular wash” means that the wash water ice was surface water at the harvesting location.
• “regular ice” means ice made from potable fresh water with the ice-making equipment at a local fish plant.
• Iodinated wash water of about 10 ppm was made by contacting an iodine crystals- containing chamber to a water supply on the trawler.
• Iodinated ice (5 ppm) was made from the iodinated water by the aforementioned ice-making equipment. The fish were kept in ice for 19 days and sampled at intervals for the purposes of microbiological, chemical and sensory (raw and cooked) analyses.
• Aerobic plate counts revealed that the use of iodinated ice had an effect on bacterial numbers.
• Significantly lower plate counts were observed when APC's of fish stored in iodinated ice were compared to those offish stored in regular ice, as follows: (i) RI was significantly lower than RR up to and including day 10 of the experiment; (ii) II was significantly lower than RR up to and including day 12 of the experiment; (iii) II was significantly lower than IR up to and including day 14 of the experiment; (iv) An overall trend of significantly lower counts for treatment RI versus treatment -R was observed for up to and including day 17 of the experiment, although differences were not significant on days 3 and 12. (v) Over the first 12 - 14 days, the APC's for RR fish on any given day ere not observed on II fish until 4 - 5 days later.

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• Chemical & Material Sciences (AREA)
• Environmental & Geological Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Hydrology & Water Resources (AREA)
• Engineering & Computer Science (AREA)
• Water Supply & Treatment (AREA)
• Organic Chemistry (AREA)
• Medicinal Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)
• Food Preservation Except Freezing, Refrigeration, And Drying (AREA)
• Apparatus For Disinfection Or Sterilisation (AREA)
• Treatment Of Water By Oxidation Or Reduction (AREA)
• Farming Of Fish And Shellfish (AREA)

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• 1998
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  • 1998-05-29 CN CN98805718A patent/CN1126718C/zh not_active Expired - Fee Related
  • 1998-05-29 JP JP50117499A patent/JP2002504851A/ja not_active Ceased
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• 2000
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