DE102011106120A1 - Operating activated charcoal, sand, egg, multilayer filter and/or membrane unit, comprises installing semiconductor-coated metal foil before activated charcoal, sand, egg, multilayer filter and/or membrane unit, and irradiating metal foil - Google Patents

Abstract

Operating activated charcoal-, sand-, egg-, multilayer filter- and/or membrane unit, comprises installing a semiconductor-coated metal foil before the activated charcoal-, sand-, egg-, multilayer filter- and/or membrane unit such that supply water is contacted with the semiconductor-coated metal foil before entering into the activated charcoal-, sand-, egg-, multilayer filter- and/or membrane unit, and irradiating the metal foil for 4-20 hours per day with light in the visible wavelength region. An independent claim is also included for using a solid metal catalyst comprising chromium (15-35%), iron and nickel (not > 60%), tramp elements e.g. manganese, molybdenum, copper, silicon and carbon (not > 15%), for operating activated charcoal-, sand-, egg-, multilayer filter- and/or membrane unit.

Description

The invention relates to a method for operating activated carbon and / or sand and / or single and / or multi-layer filter units and / or membrane units. Membrane units are understood to mean systems with a wide variety of membranes and / or membrane modules, for example microfiltration, nanofiltration, ultrafiltration, reverse osmosis, electrodeionization etc.

By the DE 10 2008 036 369 A1 For example, a method of eliminating biofilms in water-bearing or containment systems has become known by incorporating a full metal catalyst which has previously been thermally treated for a period of 5 to 60 minutes under an oxygen-containing atmosphere at a temperature of 500 to 1000 ° C into the aquifer or water Containing system is introduced and the thus pretreated catalyst is exposed to a light source. Preferred applications are swimming pools and microbiologically low-loaded cooling towers.

The DE 10 2007 042 685 A1 relates to a process for the treatment of water in water circuits of swimming pools, especially in the pool area, in the purification of filters or in the renovation of shower systems by microbially charged water after leaving a filter stage with hydrogen peroxide presettable concentration is added, the mixture then by a catalyst Thereafter, the water is treated with chlorine and / or sodium hypochlorite and / or chlorine dioxide and / or other chlorine-containing disinfectants or hydrogen peroxide and / or with UV radiation, and the water thus treated either in the pelvic area and / or in the inlet introduced to the filter and / or used for flushing water pipes and / or shower systems. This prior art has the disadvantage that hydrogen peroxide is required as an additional chemical, which may lead to the following problems: undesired interaction with chlorine, increased risk potential and costs for chemical and dosing technology.

The invention has for its object to provide an alternative method for operating activated carbon and / or sand and / or single and / or multi-layer filter units and / or membrane units. The task is further to clean the addressed filter and / or membrane units without the use of chemicals and to keep permanently free of unwanted microbiological deposits (fouling).

This object is achieved in that before the activated carbon and / or sand and / or single and / or multi-layer filter unit and / or membrane unit a semiconductor-coated metal foil is installed so that the feed water before entering the activated carbon and / or sand - And / or single and / or multi-layer filter unit and / or membrane unit in contact with the semiconductor-coated metal foil occurs, and that the metal foil for a period of at least 4 and max. Irradiated with light in the visible wavelength range for 20 hours daily.

Advantageous developments of the method according to the invention can be found in the dependent claims.

Notwithstanding the prior art can be dispensed with by the subject invention on the addition of chemicals such as hydrogen peroxide. The respective filter and / or membrane unit can thus be cleaned without chemicals and kept permanently free of microbiological deposits (fouling). This applies to filter units and membrane units in a wide variety of areas, in particular drinking water, swimming pool water, process water, cooling water treatment and the treatment of water for irrigation and humidification.

It is advantageous if the metal foil produced from the main components iron, chromium and nickel, while the semiconductor layer of oxides, respectively mixed oxides, of these elements is formed. Remaining constituents may be, for example: molybdenum, manganese, copper, silicon and carbon.

According to a further aspect of the invention, the metal foil is irradiated daily with light in the visible wavelength range for at least four hours, but at most for 20 hours.

It is advantageous if the metal foil is irradiated with LED.

In addition, it is proposed that in the DE 10 2008 036 369 described full metal catalyst for the inventive method for operating activated carbon and / or sand and / or single and / or multi-layer filter units and / or membrane units to use.

As an example, for the treatment of 0.5 to 50 m ³ / h water depending on the water quality required: 0.1-1 m ² catalyst film in activated carbon and gravel filters up to 1 m ² filter area (corresponding to a filter speed of 0.5 -50 m / h) and at membrane units of 5-5000 m ² (corresponding to a flux of 0.1 to 10,000 L / m ² h.

The following examples describe the process according to the invention for operating activated carbon and / or sand and / or single and / or multi-layer filter units and / or membrane units:

example 1

In a swimming pool with a water volume of 75 m ³ , a water volume flow of 70 m ³ / h and a water temperature of 36 ° C, the water treatment is carried out in the following order:
The pool water flows into a treatment plant, in this example consisting of an ozone plant with an ozone input of at most 1 g / m ³ , in this example an activated carbon layer as a filter unit with a height of 0.15 m and a cross section of 2.5 m × 2 , 5 m (corresponding to 6.25 m ² and a filter speed of 12 m / h) and an average grain size of 0.8 to 1.0 mm and a filter gravel layer with a height of 1.0 m, a cross section of 6.25 m ² and an average grain size of 0.71 to 1.25 mm. Subsequently, the pool water is passed through a pH regulation path and a chlorination, which according to a chlorine content in the pool DIN 19643 ensures that the bath water is finally returned to the pool.

Despite this treatment, an undesirably high microbiological burden was observed in the course of the treatment plant.

Then, between the ozone plant and the activated carbon layer 0.6 m ^{2 of} a semiconductor-coated metal foil consisting of about 30 wt .-% chromium, iron and nickel and about 10% of other elements, in particular Mo, Cu, Mn, Si and C. introduced in the metal and the oxides or mixed oxides of the metals in the semiconductor layer, in the form of films having a thickness of about 20 microns and irradiated for 15 hours daily with an LED with a power consumption of 4.5 W.

At a microbiological initial load well above the upper guideline according to DIN 19643 the microbiological burden dropped to zero cfu / ml within 5 weeks.

Although the example includes an ozone plant, the same is not necessary for the operation of the respective filter unit and / or membrane unit per se. Ozone thus does not constitute an essential element for the execution of the subject invention, as well as other of the filter unit and / or membrane unit possibly upstream or downstream disinfection and / or oxidation plants.

Example 2:

In a plant for the production of up to 20 m ³ / h boiler feed water for power plant operation was after ultrafiltration and before the first stage of a reverse osmosis system 0.15 m ^{2 of} a semiconductor-coated metal foil, each consisting of about 30 wt .-% chromium, iron and nickel and about 10% of other elements, in particular Mo, Cu, Mn, Si and C in the metal and the oxides or mixed oxides of these elements in the semiconductor layer, introduced in the form of films having a thickness of about 20 microns and for 12 h irradiated daily with a 2.5 W LED.

The biocide treatment (150 ppm DBNPA) previously used instead of the semiconductor-coated metal foil was decommissioned.

Compared to the previous biocide treatment, the permeate throughput in the first reverse osmosis system increased by approx. 10% to almost 23 m ³ / h from 20 m ³ / h, whereby the pressure loss remained stable at approx. 1.5 bar. In the subsequent second reverse osmosis system, the permeate throughput of 14 m ³ / h rose by about 5% to over 15 m ³ / h, the pressure loss decreased by about 10% from 0.65 bar to just under 0.6 bar.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008036369 A1 [0002]
• DE 102007042685 A [0003]
• DE 102008036369 [0011]

Cited non-patent literature

• DIN 19643 [0014]
• DIN 19643 [0017]

Claims (7)

A method for operating activated carbon and / or sand and / or egg and / or multi-layer filter units and / or membrane units, characterized in that before the activated carbon and / or sand and / or single and / or multi-layer filter unit and / or Membrane unit is installed a semiconductor-coated metal foil so that the feed water before entering the activated carbon and / or sand and / or single and / or multi-layer filter unit and / or membrane unit in contact with the semiconductor-coated metal foil occurs, and that the metal foil for a Period of at least 4 and max. Irradiated with light in the visible wavelength range for 20 hours daily. A method according to claim 1, characterized in that the metal foil of the main components iron, chromium and nickel and secondary components, in particular molybdenum, copper, manganese, silicon and carbon, produced and the semiconductor layer is formed on the metal foil of oxides, respectively mixed oxides of these elements , A method according to claim 1 or 2, characterized in that the metal foil is irradiated with LED. Method according to one of claims 1 to 3, characterized in that the respective activated carbon and / or sand and / or single and / or multi-layer filter unit and / or membrane unit upstream or downstream of a disinfection and / or oxidation plant, wherein the semiconductor-coated metal foil is always installed in front of the respective filter and / or membrane unit. Use of a full metal catalyst of the following chemical composition (in% by weight): Cr 15-35% Fe + Ni minute 60% wherein the proportion by weight of accompanying elements, for example Mn, Mo, Cu, Si, C in total does not exceed 15%, for operating activated carbon and / or sand and / or single and / or multi-layer filter units and / or membrane units. Use according to claim 5, wherein the all-metal catalyst comprises accompanying elements individually or in combination (in% by weight) of the following elements. Mn up to 5% Not a word up to 10% Cu up to 5% Si up to 1% C up to 1%. Use according to claim 5 or 6, wherein the catalyst is present as a sheet or foil.