DE10029082A1 - Noble metals employed for water sterilization are pre-activated prior to insertion in remote water supply - Google Patents

Abstract

A multi-stage process uses activated noble metals contained within e.g. a gauze to render water suitable for household drinking and non-drinking purposes and to prevent its recontamination.

Description

Microbiologically contaminated drinking water can be too heavy to drink Lead diseases. To prevent this, drinking water is through appropriate physical-chemical processes prepared. To one Ensuring sustainable protection against recontamination will treated drinking water e.g. B. added chlorine.

Do you leave drinking water for a long time or do you prepare it available from the utilities through the public grid provided drinking water by activated carbon filtering or by reverse Osmosis at the point of use to improve taste or for further Reduction of unwanted ingredients afterwards, then this goes Protection against recontamination by removing the water Chlorine lost. So it is known that the predominantly in domestic Area used filter systems for drinking water aftertreatment inside germinate in such a short time that z. B. the guideline values of drinking water server order clearly exceeded and this water out microbiological reasons unsuitable for human consumption is not. The same applies to drinking water filled in tanks (e.g. mobile homes le) or for humidifiers and air conditioners, where often inside strong germs can be observed within a few days.

These germs are absorbed when drinking or evaporate with the released water. In the latter case, this can lead to the so-called Lead humidifier fever. One sets biocides as protection against germs Active ingredients too, then when drinking or breathing added. This can lead to serious illnesses.  

In closed systems such as those filled in water beds Due to the onset of microbiological activity, water becomes a Gas evolution is observed, which is a regular exchange of the Water required.

Hot water tanks or simple ones are also critical Under table boilers, in which due to the increased temperature who can develop dangerous bacterial loads.

Hygienically perfect drinking water is one of the most urgent Developing country problems. Those used in the "First World" Technologies for drinking water disinfection are expensive and must be kept up to date serviced and checked. The elaborate control, measurement and Control technology can only be mastered by qualified specialists. These systems can only be operated cost-effectively as a central system what an appropriate infrastructure requires. This advance There are no settlements in the "Third World".

For the above areas of application, simple, maintenance-free, self-regulating systems are developed that are inexpensive can be operated decentrally, i.e. directly at the point of use. she must also be maintenance-free for a long period of time (years) Ensure reliable disinfection of drinking and industrial water.

The invention described here is based on the problem that a safe use of the usually used for the disinfection of drinking water technologies is only guaranteed if a continuous The relevant operating parameters are monitored simultaneously ensure permanent support by qualified specialists steady and you have a functioning infrastructure - pipeline network - features. These conditions are especially in the third world and not or only partially given in the domestic area. The high Costs and / or the lack of qualified personnel speak here on the other hand.  

Due to the problems outlined above, drinking water in large parts of the so-called "Third World" is significantly microbially contaminated. The photochemical (UV disinfection) or chemical processes based on silver mainly used for aftertreatment systems in the domestic area ("First World") have the following disadvantages:

• 1. No depot effect - UV light.
• 2. Uncontrolled release and thus exceeding the Silberio limit value - coated activated carbon, ion exchange.
• 3. Expensive and cumbersome - adding tablets or drops (Silver compounds).

These problems are solved with the method formulated in claims 1-3. This process is based on the chemical etching of elemental silver surfaces with the aim of removing existing passivation layers (see Figure 1). Solid bodies, wires, wools made of silver, interwoven silver wires or silver blended fabrics or supports coated with silver are suitable as the base material.

In a second step, the etched, that is, the activated surface is rinsed off and then conditioned. The conditioning is carried out by immersing in a salt solution, whereby the etched surface is converted into a defined chemical state (see Figure 1).

This chemically defined surface is self-regulating because it is able to correspond with the silver ions released into the drinking water (see Figure 2). This ensures that the amount of silver released

• 1. sufficient to ensure reliable disinfection,
• 2. A sufficient deposit effect is achieved and
• 3. Safe the prescribed maximum amounts of free silver ions be undercut.

The silver ions detached from the surface are replenished from the core of the base material (see Figure 2). This ensures that there is always enough active silver ion on the surface.

A silver surface treated according to claims 1-3 is thus:

• 1. Self-regulating - interaction of the surface with the loosened Silver ions.
• 2. Self-renewal - interaction of the surface with the Base material.

It is therefore possible to reliably supply drinking water with little effort sterilize or protect against recontamination. Through the Conditioning is achieved so that on the one hand the guide values are observed and on the other hand enough silver ions are released to to ensure sustainable protection. About the crowd and that The ratio »silver in the core / conditioned surface« can be Control the absolute amount of silver ions depending on the water quality. The amount of material used determines the tool life, which is clear is over a year. Through self-regulation and renewal the use of measurement, control and regulation technology can be dispensed with.

The materials treated according to claims 1-3 can be introduced into the water cycle at any point. The material itself is either in separate cartridges, which are integrated into the line using standard connection technologies, or it is located directly in the filters or in the tanks (see Figures 3a-c). Depending on the intended use, silver wire, silver wool or a plastic fabric woven with silver wire is preferably used as the base material.

PRACTICE TESTS I. Activated carbon filter Untersuchungsobkekt

Pressed activated carbon, silver wool treated according to patent claims 1-3, silver wool was in the product water collecting channel ( Fig. 2b), test after a 4-week service life, tests carried out by test users. The stagnation water in the extraction line and, after the preliminary run, filtered water were examined. Test results [Hygiene Institute Tübingen, laboratory no .: 3528/9, 3531/2, 13.07. 1995 and test report dated July 26, 1995]:

test result

The guidelines are adhered to. By the Verkei Protection against contamination was prevented, as usual, from germs spreading over the Intake line could penetrate and colonize the filter.

II. Reverse osmosis systems Untersuchungsobkekt

House osmosis system, with tank, contaminated during operation. The osmosis water produced was unsuitable for human consumption (Dr. Weßling laboratory, test report 523429 / pr). After introducing the protection against germs (as shown in Fig. 2c), the bacteriological findings met the requirements of the Drinking Water Ordinance (test report 524151). Execution by test users.

In the case of osmosis water, the silver concentration is higher than due to the system with city water filtered only via activated carbon (e.g. test report from February 12, 1996, Aquaterr Umweltanalytik GmbH). The values are e.g. T. about the general limit of 0.01 mg / l but still below the limit value of 0.08 mg / l for drinking water treated with silver. The silver If desired, concentration can be interposed "Modulators" to the values as given in Example 1 reduce.

The test user equipped several osmosis systems, which continuously z. B. controlled by health authorities. Until At the time of application, i.e. after more than 4 years of use, was at none of the monitored systems observed a drop in effectiveness. During this time, no maintenance work or even a material was found exchange instead.

Thus, the practical tests show that with these according to the patent claims 1-3 treated materials a reliable long-term protection against Contamination in drinking water systems etc. can be built up. equal In time the results prove that using these materials is not just one Protection against recontamination can be built up, but also bacteriolo highly contaminated water is easy to disinfect and the requirement changes to the Drinking Water Ordinance, also with regard to pollution of the drinking water with silver ions. So this can Process also for drinking water treatment bacteriologically contaminated Surface water, wells etc. can be used.  

The advantageous implementation of the method can be seen from the demonstrate the example below.

I. USE OF SURFACE-TREATED SILVER / PLASTIC FABRIC OR SILVER WOOLS IN HOUSE PLANTS FOR POST-AFTER ACTION OF TOWN WATER

Activated carbon filters or so-called reverse osmosis systems for domestic use remove the chlorine used to protect against reverse heating. This means that the filters are quickly populated by microorganisms, which lead to a strong bacteriological load on the drinking water. To prevent this, a silver / plastic fabric treated according to the patent claims can be wrapped around the filter membrane (reverse osmosis) or the filter block (pressed activated carbon blocks), which prevents direct settling of the filter media ( Fig. 3a). Alternatively, a silver wool treated according to the patent claims can be introduced into the collecting pipe of the product water (reverse rosmose, activated carbon - both pressed blocks and granulate) ( Fig. 3b). Water treated in this way is germ-free and protected against recontamination due to the dissolved silver ions. If, in principle, the aftertreated water has to be temporarily stored (storage tank), then a cartridge loaded with silver wool or silver / plastic fabric can also be inserted ( Fig. 3c).

Depending on the initial load and the general situation, the possibilities can be combined. As a rule, however, one of the three options is sufficient to ensure adequate protection in city water aftertreatment systems or in well water. In systems without the tank in particular Figures 3 variants b shown are used a, while in systems with tank preferably, the variant shown in Figure 3c or their combina tion is used.

II. USE OF SURFACE-TREATED SILVER / PLASTIC FABRIC OR SILVER WOOL IN HUMIDIFIERS, TANKSY STEMEN OR IN CLOSED SYSTEMS

In air humidifiers, hot water tanks or under-table boilers, water tanks (camping) or in water beds, a strong increase in microbiology is observed over time. This leads to health hazards (humidifiers, water tanks etc.) or to an increased need for maintenance (replacement of water in water beds because gas bubbles form due to microbiological activities). This can be prevented by using a silver / synthetic fabric treated according to the patent claims or by using a corresponding silver wool ( Fig. 4). The silver-based materials can either be introduced directly or in water-permeable housings. With appropriate humidifier types, the silver / plastic fabric can also be placed directly on the filter mats.

III. USE OF SURFACE-TREATED SILVER / PLASTIC FABRIC OR SILVER WOOL FOR DECENTRAL DRINKING WATER DISINFECTION - "THIRD WORLD"

Hygienically perfect drinking water is only available to a limited extent in the Third World. In view of the lack of infrastructure, simple, decentralized drinking water treatment must be made available. For this, silver / plastic fabrics or silver wool treated according to the claims can be used advantageously. In the simplest case, the silver / plastic fabric or the silver wool is placed in the storage container - water container - and the containers are then filled with the well or river water that has been drawn ( Fig. 5).

If rainwater is collected in cisterns, a corresponding amount of silver / plastic fabric or silver wool can be introduced into the cistern or into the outlet (if available) ( Fig. 5).

Drinking water disinfection with silver / plastic fabrics or silver wool treated according to the patent claims can be combined with other technologies. So this technology together with a water pump and a simple filter system such. For example, a combination of sand and activated carbon filters represents a complete, easy-to-use water treatment system. Depending on the technical conditions, further combinations can be implemented ( Figure 5).

Claims (3)

1. Process for disinfection and prevention of recontamination of drinking and industrial water by activated precious metals, characterized in that the necessary or sufficient activity to develop the disinfecting effect is set by a multi-stage pretreatment. 2. The method according to claim 1, characterized in that due to the activity setting on the control, measuring and dosing units directions can be dispensed with. 3. The method according to claims 1 and 2, characterized in that the materials used last for several years without additional Allow maintenance work.