Water filtering device
A water filtering device suitable for locally, under atmospheric pressure, purifying contaminated water, and which comprises a container that is provided with an inlet opening and an outlet opening, which container is provided with at least: a preliminary filtration element for the removal of particles, if present, of a particle size more than 10 micrometers; a filtration element provided with activated charcoal; and an ultrafiltration element.
1. A water filtering device comprising a container that is provided with an inlet opening and an outlet opening, which container is provided with at least:
a hydrophilic preliminary filtration element for removal of particles, if present, of a particle size more than 10 micrometers;
a filtration element provided with activated charcoal; and
an ultrafiltration element; and
wherein the preliminary filtration element and the filtration element comprising the activated charcoal are combined into a sandwich structure; and
wherein the water filtering device purifies water under atmospheric pressure.
2. A water filtering device according to claim 1 , wherein the preliminary filtration element is a flat asymmetrical filter having a non-uniform pore size distribution, which is positioned in such a way that when in use, the water stream flows from large to small pores.
3. A water filtering device according to claim 1 , wherein the preliminary filtration element has a thickness ranging from 1-10 micrometers.
4. A water filtering device according to claim 1 , wherein the preliminary filtration element is comprised of a composite of hydrophilic materials.
5. A water filtering device according to claim 1 , wherein the water filtration element comprising the activated charcoal is composed of a layer of activated charcoal on a carrier material.
6. A water filtering device according to claim 1 , wherein the ultrafiltration element comprises a filter housing provided with an inlet and an outlet connection in which a bundle of capillary ultrafiltration membranes is provided, which are open at a first end and closed at another end, and which at the first end are set in a membrane holder that seals off the gap between the capillary ultrafiltration membranes and the filter housing, the capillary ultrafiltration membranes having an asymmetrical pore structure, such that the pore structure is gradually reduced in the stream direction of the liquid stream through the membrane wall.
7. A water filtering device according to claim 6 , wherein the ultrafiltration membranes are permanently hydrophilic.
8. A water filtering device according to claim 1 , wherein the outlet opening of the water filtering device is connected with a storage reservoir.