Field of invention

The present invention relates to a process for preparing drinking water for live animals by electrochemically activating aqueous salt solutions. More specifically, the invention relates to a process of producing an additive to regular water obtained from wells at a farm site, where the additive is an anolyte that has been produced by electrolysis of aqueous sodium chloride in a membrane reactor. The invention also provides a method of using water containing specific amounts of free available chlorine as drinking water for live animals.

Technical background

Electrolysis processes of aqueous alkali chloride solutions for producing chlorine, hydrogen and alkali metal hydroxides are well-known in the art. One such process is disclosed in US 4,108,742, wherein the electrolysis is carried out in a cell that has been divided into cathode and anode chambers by a cation exchange membrane. As one objective of the technology of US

4,108,742 is to produce chlorine gas, the electrolysis reaction is run at a low pH.

Electrochemical activation or electro-activation of dilute salt solutions in water has been the subject matter of several prior patents and publications. The prior art commonly discloses the use of electrochemical activation to produce an anolyte solution and a catholyte solution. Those who are engaged in the art will appreciate that an anolyte solution has a positive oxidation-reduction potential (ORP) or redox potential, which is oxidizing and has microbiocidal properties. The catholyte solution, on the other hand, has a negative ORP, has dispersive and surface active properties and can be used as a reducing agent.

Salts used in the prior art almost exclusively refer to sodium chloride (NaCI) and in most prior art applications chloride-based salts are used in a diluted form. However, there are various applications in which anolyte or catholyte are used in an undiluted form, but in many of these applications a major disadvantage of chloride-based or chloride-derived activated solutions is that they are corrosive to the materials with which they come into contact. This is particularly intolerable in medical applications where the solutions typically could be used for cold sterilization of medical instruments.

One such sterilization technology is disclosed in GB, A, 1 ,428,920. According to this document, a bacteria-laden surface is disinfected by applying a solution of hypochlorous acid generated by electrolyzing an aqueous solution of NaCI at a pH within the range of 6 - 7. Another similar disinfection method is described in WO99/20129. An animal product is exposed to an

electrochemically activated, anion-containing aqueous solution. As a consequence, potentially harmful and/or destroying microorganisms are killed and the shelf life of the animal product is prolonged.

It should be kept in mind that object of the technology disclosed in GB

1 ,428,920 as well as WO99/20129 is sterilization and thus to kill all microorganisms around. When carrying out such processes, presence of chlorine gas is not considered to be a serious drawback and substantial amounts of chlorine are indeed released. It has generally been considered to be much more important to achieve a high degree of sterilization than to protect the close environment from high doses of chlorine. When breeding domestic animals such as cows, pigs and poultry, it is important to consider contamination of potentially harmful microorganisms. Typically, the environment in cowsheds, barns, pigsties and poultry-houses is very rich in microorganisms. Water is continuously provided. Both animal feed and drinking water vessels may be contaminated. Such contamination of pathogenic microorganisms could lead to health problems for the animals. Furthermore, water from local wells is often used as drinking water for such animals and often without any further treatment. It is a known fact that the quality and composition of such water is not constant but varies with time. It is also important to consider that domestic animals need a functional and beneficial microflora in their alimentary channel as well as a safe environment essentially free from toxic substances such as chlorine. Especially ruminants such as cattle, sheep and horses are highly dependent on a beneficial and stable microflora in their stomachs and intestines in order to be able to digest their natural feed. Addition of conventional antibiotic substances to fodder and drinking water leads to several problems. Firstly, there is a high risk for development of microbial resistance to such antibiotic substances. Secondly, antibiotic substances may cause allergy. Consequently, presence of antibiotic substances in meat, eggs and other food products may lead to allergic and anaphylactic reactions in humans and other animals eating these products. Presence of high amounts of chlorine gas in drinking water could also harm the domestic animals due to loss of beneficial microorganisms in the alimentary channel and toxic side effects.

Accordingly, there is a need for a technology for reducing microorganisms in water and fodder in animal shelters such as cowsheds, barns, pigsties and poultry-houses, which does not harm the normal microflora of domestic animals, such as cows, sheep, pigs and poultry and which does not involve using toxic or antibiotic substances potentially causing undesired toxic effects, microbial resistance and allergy problems.

Summary of the invention

A first object of the present invention is to solve the above mentioned problems by providing a method of using water having a pH within the range of 6.0 - 7.0, said water containing an anolyte fraction obtained by electrolysis of an aqueous solution of sodium chloride, said water having a free available chlorine (FAC) content within the range of 0.10 - 0.60 ppm, as drinking water for domestic animals kept indoors for maintaining and/or improving their growth. A second object of the present invention is to provide a method for preparing drinking water for domestic animals kept indoors, for example in a barn, a cowshed, pigsty and/or a poultry-house, comprising the steps of:

a) providing incoming water and, monitoring the pH thereof as basic waterflow pH;

b) dividing said incoming water into one basic water flow and one process water flow;

c) adding sodium chloride, to said process water flow;

d) conveying said process water flow containing sodium chloride to a through flow electrochemical reactor having a cathode chamber and an anode chamber separated by a membrane, and where each chamber contains an electrode, wherein the process water flow is first transported through said cathode chamber and subsequently through said anode chamber;

e) when transporting said process water through said chambers,

simultaneously applying a voltage over the electrochemical reactor and leading an electrical current through said membrane resulting in formation of an anolyte fraction in the anode chamber and a catholyte fraction in the cathode chamber;

f) injecting anolyte formed in step e) into said basic water flow, thereby obtaining drinking water for domestic animals kept indoors,

wherein:

pH is determined for the basic water flow and oxidation reduction potential (ORP) is determined for the resulting water flow being formed after injecting anolyte into said basic water flow, which data regarding basic water flow pH and ORP is used to control injection of anolyte in step f) in such a way that the free available chlorine (FAC) content of the resulting water is in the range of 0.10 - 0.60 ppm.

A third object of the invention is to provide a system for controlling addition of anolyte produced by electrolyzing an aqueous solution of sodium chloride, said anolyte being added to a basic water flow, said system comprising

an ORP sensor;

a first pH sensor; a water flow sensor;

an injection means;

a memory means; and

a control and calculation means,

wherein

said ORP sensor is set up to measure ORP in the basic water flow after injection of anolyte and to send ORP data to said control and calculation means;

said pH sensor is set up to measure pH in the basic water flow and to send pH data to said control and calculation means;

said water flow sensor is set up to measure flow value of the basic water flow and to send flow value data to said control and calculation means; said injection means is set up to inject anolyte into the basic water flow in response to signals from said control and calculation means;

said memory means contains data regarding free available chlorine in an anolyte produced by electrolyzing an aqueous solution of sodium chloride as a function of pH and ORP and said memory means is set up to such data to said control and calculation means; and in that

said control and calculation means is set up to receive ORP data from said ORP sensor, pH data from said pH sensor, and flow value data from said flow sensor, and in that said control and calculation means is set up to determine how much anolyte that has to be added in order to obtain a free available chlorine (FAC) content of the resulting water within the range of 0.10 - 0.60 ppm.

Detailed description of the invention

The present invention is based on the discovery that domestic animals, such as cattle, sheep, pigs and poultry, could be harmed if they are exposed to unnecessarily high amounts of chlorine gas. In fact, ruminants such as cattle and sheep are extra sensitive because their food digestion process is highly dependent on a beneficial and stable microflora in their stomach

compartments and intestines. Loss of that microflora in addition to other toxic effects of chlorine could be fatal for a ruminant but it could also harm other domestic animals such as pigs and poultry.

In order to take care of the above mentioned problem with undesired microbial growth in drinking water, anolyte preparations have been used as disinfecting agents. In case the pH of the water is within the range of 6.0 - 7.0, chlorine in an anolyte is mostly present as hypochloric acid and not as chlorine gas. Furthermore, hypochloric acid is not stable at alkaline and acid pH and it is therefore beneficial to maintain a pH within the range of 6.0 - 7.0 in case high amount of hypochloric acid is desired.

Domestic animals at farms are often given water from local wells, lakes, rivers or streams. Typically, such water is not pretreated before giving it to the animals and its composition and pH may therefore vary with time. In case an anolyte would be added to such water without any further consideration, the resulting chlorine content could be far too high for the animals and they could be severely, if not fatally, harmed.

The first object of the present invention is to provide water having a pH within the range of 6.0 - 7.0, and where said water contains an anolyte fraction obtained by electrolysis of an aqueous solution of sodium chloride, and where it has a free available chlorine (FAC) content within the range of 0.10 - 0.60 ppm, as drinking water for domestic animals kept indoors for maintaining and/or improving their growth. Regarding ruminants such as cattle and sheep, it is preferred that the FAC content is within 0.14 - 0.40 ppm. Regarding other animals, such as pigs and poultry, it is preferred that the FAC content is within 0.4 - 0.6 ppm. FAC values below 0.10 ppm do not have a sufficient effect against undesired microbial growth and FAC values above 0.60 ppm may harm the animals.

Information regarding determination of FAC values, as well as tables of FAC as a function of pH and ORP (oxidation reduction potential) can be found in Technical Bulletin No. 24, issued by Aquarius Technologies Pty. Ltd. (AU) (http://www.aquariustech.com.au/pdfs/tech- builetins/Undrstnd Qx Bio QRP.pdf)

As herein disclosed, the terms "anolyte" and "catholyte" respectively, relates to fractions obtained in the chambers of an electrochemical flow reactor. The anolyte is produced in the anode chamber and the catholyte in the cathode chamber. The chambers of such an electrochemical flow reactor are typically separated by a membrane, such as a ceramic membrane. The second objective of the present invention is to provide a method for preparing drinking water for domestic animals kept indoors, for example in a barn, a cowshed, pigsty and/or a poultry-house. The method comprises the steps of:

a) providing incoming water and monitoring the pH thereof as basic water flow pH;

b) dividing said incoming water into one basic water flow and one process water flow;

c) adding sodium chloride, to said process water flow;

d) conveying said process water flow containing sodium chloride to a through flow electrochemical reactor having a cathode chamber and an anode chamber separated by a membrane, and where each chamber contains an electrode, wherein the process water flow is first transported through said cathode chamber and subsequently through said anode chamber;

e) when carrying out step d) simultaneously applying a voltage over the electrochemical reactor and leading an electrical current through said membrane resulting in formation of an anolyte in the anode chamber and a catholyte in the cathode chamber;

f) injecting anolyte formed in step e) into said basic water flow, thereby obtaining drinking water for domestic animals kept indoors,

wherein:

pH is determined for the basic water flow and oxidation reduction potential (ORP) is determined for the resulting water flow being formed after injecting anolyte into said basic water flow, which data regarding basic water flow pH and ORP is used to control injection of anolyte in step f) in such a way that the free available chlorine (FAC) content of the resulting water is in the range of 0.10 - 0.60 ppm. It is preferred to produce a resulting water having a FAC content of 0.14 - 0.40 ppm regarding ruminants and 0.4 - 0.6 ppm regarding poultry and pigs.

It is preferred that the addition of sodium chloride in step c) is controlled based on information about the electrical current through the membrane of the chemical reactor.

The term "incoming water" relates to any kind of water that is available at a typical farm site.

The electrochemical reaction of the aqueous sodium chloride solution results in formation of an anolyte containing a high amount of hypochloric acid. A high voltage and a high original concentration of sodium chloride leads to a higher concentration of hypochloric acid. As is suggested above, hypochloric acid is not stable over a longer time period but decomposes back to a chloride salt over time. It is therefore advantageous to use the anolyte quite soon after it has been produced.

It is preferred that ions selected from the group of Fe ²⁺ , Fe ³⁺ , Mn ²⁺ and Ca ²⁺ , and optionally humus particles, are removed from the process water flow by suitable filters. It is preferred to adjust pH of the basic water flow to a value within the range of 6.0 - 7.0, and monitor the adjusted pH as basic water flow pH.

It is also preferred that catholyte is injected into the basic water flow at specific times. The catholyte fraction has a high content of anti-oxidants and it is believed that it stimulates the immune system of domestic animals.

Typically, the catholyte fraction could be added at times when the animals are used to feed. Then, they drink much more than otherwise and hence, water is consumed so fast that there is not time for microbial contaminations to form. The third objective of the present invention is to provide a system for controlling addition of anolyte produced by electrolyzing an aqueous solution of sodium chloride, said anolyte being added to a basic water flow, said system comprising

an ORP sensor;

a first pH sensor;

a water flow sensor;

an injection means;

a memory means; and

a control and calculation means,

wherein

said ORP sensor is set up to measure ORP in the basic water flow after injection of anolyte and to send ORP data to said control and calculation means;

said pH sensor is set up to measure pH in the basic water flow and to send pH data to said control and calculation means;

said water flow sensor is set up to measure flow value of the basic water flow and to send flow value data to said control and calculation means; said injection means is set up to inject anolyte into the basic water flow in response to signals from said control and calculation means;

said memory means contains data regarding free available chlorine in an anolyte produced by electrolyzing an aqueous solution of sodium chloride as a function of pH and ORP and said memory means is set up to such data to said control and calculation means; and wherein

said control and calculation means is set up to receive ORP data from said ORP sensor, pH data from said pH sensor, and flow value data from said flow sensor, and in that said control and calculation means is set up to determine how much anolyte that has to be added in order to obtain a free available chlorine (FAC) content of the resulting water within the range of 0.10 - 0.60 ppm. It is preferred that the system comprises a second pH sensor for monitoring pH of the anolyte. The sensor is set up to transfer the information to the control and calculation means. All components of the system are standard components which should be well- known to the skilled person. Accordingly, the ORP sensor is typically a set of electrodes such as a reference electrode and a measuring electrode that is used to measure the oxidation reduction potential of an aqueous sample. It is referred to Technical Bulletin No. 24 from Aquarius Technologies Pty. Ltd., above. Likewise, any electrode capable of measuring pH of an aqueous sample could be used. Furthermore, the injection means and water flow sensor are also standard components. The memory means and the control & and calculation means constitute parts of a computer system set up to calculate how much anolyte that has to be added in order to obtain a resulting water having the desired characteristics.

The invention will now be described with reference to the enclosed figure, wherein:

Figure 1 discloses a sketch of the process according to a preferred

embodiment of the second object of the present invention.

As already mentioned, the present invention relates to a method for preparing drinking water for domestic animals based on local incoming water. The incoming water typically originates from a well but may also originate from a river, lake or another water source. Referring to figure 1 and according to a preferred embodiment of the present invention, incoming water flow 1 at a farm site is conveyed through pH sensor 6, which continuously sends pH data to control and calculation means 56, to a branch point 8. At that point, the incoming water flow is divided into a basic water flow and a process water flow. The process water flow is lead through humus/particle filter 2 and a filter 4 absorbing ions, such as Ca ²⁺ , Fe ²⁺ , Fe ³⁺ and Mn ²⁺ . Filter 4 is typically composed in response to a chemical analysis of the incoming water. The process water is then transported to another branch point 10, where a small portion of the water flow is lead through magnet valve 12 to sodium chloride tank 14, wherein sodium chloride is added manually. The amount of saline in sodium chloride tank 14 is monitored by level sensor means 16, which controls magnet valve 12. When the saline level in tank 14 falls under a predetermined level, level sensor means 16 sends signals to magnet valve 12 so that the valve 12 is opened. Saline is pumped off from sodium chloride tank 14 by dosage pump 20. The remaining portion of the process water flow is forwarded by pressure regulation means 18 to branch point 22, where it is reunited with saline from dosage pump 20. The united process water is then forwarded to electrochemical reactor 42, wherein it is pumped into cathode chamber 28 . The cathode chamber is separated from anode chamber 26 by a ceramic membrane 24 and an electric current is lead through the

membrane. The current is measured by current measurement means 30 which in turn controls dosage pump 20. A higher current results in more saline transported by dosage pump 20. The flow out from cathode chamber 28 is controlled by valve means 32. The produced catholyte may be forwarded to tank 36 in case it is interesting to produce the catholyte fraction. However, the catholyte fraction is normally forwarded to anolyte chamber 26. After leaving the anolyte chamber 26, the produced anolyte is collected in tank 34. Both anolyte tank 38 and catholyte tank 36 are connected to injector means 48, which in turn is controlled by control and calculation means 56. Injection means 48 injects anolyte (and at specific times only catholyte) through branch point 50 into the basic water flow. Most of the basic water flow from branch point 8 is lead through branch point 50 before reaching water flow sensor means 58. Water flow sensor means 58 is connected to control and calculation means 56 and continuously monitors the basic water flow. Subsequently, the basic water flow is lead through an ORP sensor 52 which also is connected with control and calculation means 56 and continuously monitors ORP of the basic water flow. When the basic water flow has passed through ORP sensor 52, it is forwarded 54 to animals as drinking water.

Accordingly, control and calculation means 56 continuously receives signals from pH sensor 6, water flow sensor 58, and ORP sensor 52. Using calibration data stored in memory means 60, control and calculation means 56 controls injection means 48 in such a way that free available chlorine (FAC) in the outgoing drinking water 54 is within the range 0.1 - 0.6 ppm.

It is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the

accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not for limitation.