Ultra Membrane filtration systems                                   Water flow rates & specifications | operating manual | prices |

Why

Ultra filtration will prevent bacteria including Legionella, Viruses , Fungi and parasites such as cryptosporidium entering your water supply.  If you want your water to be safe without having to remove dissolved minerals, then Ultra Filtration is the best choice.  UV and ozone do not remove cryptosporidium parasites (click here  for report) and only give a reduction of bacteria, viruses and fungi levels. Ultra filtration gives absolute filtration, and will absolutely remove everything in the water down to 0.01microns ( 0.00001 mm).

If you want a point of entry filtration system that will give you safe water from disease and infection, then Ultra Filtration, will give you this security.  It is not possible for UV to give you this level of protection.

Applications

• Whole house systems
• Hospitals
• Nursing homes
• Leisure Centers
• Swimming Pools
• Any public building

whole house water treatment

Our membrane filtration system will filter all of the influent water to your house at a rate of 460 litres per hour, larger units are available.  The membrane is self cleaning so there is very little that you need to do to keep the system running.  If you have an issue with bacteria and viruses in your water supply,  a UV disinfection unit will give a 10² to 10³ times reduction in the bacterial levels, however UV is not all that effective against a virus unless the irradiation dose is over 200mwatts/cm/sec.  UV is totally ineffective against cryptosporidium oocysts, and considering that this organism is responsible for 50% of all water born infections, this is a serious issue.

Membrane filtration gives absolute filtration down to 0.01 microns (30 nm nanometers), which provides a 10⁶ reduction in bacterial levels, 10³ reduction in virions and effectively 100% removal of cryptosporidium oocysts. Membrane system are not affected by the quality of the water.  For example if the solids load were to increase,  the worst that can happen is that the filter blocks and flowrates decrease until the unit back-washed. With UV,  the performance of the system is linked to the quality of the water.  If the iron content increases, or if there is any colour or solids in the water,  then the performance of a UV unit will decrease exponentially.

To summarize,  if you want you water supply to be safe and secure, the best and safest approach is to use a membrane system.  The equipment will be more expensive that a UVc system, however the running and maintenance costs will be a great deal lower. The Life Cycle cost saving with membranes against UV is approximately 12 months.  If you wish to use UV then our recommendation for ultimate security is to use our membrane system followed by UVc, the combination of membranes and UVc irradiation at 40mwatts/cm/sec will provide the best possible water quality security for your home.

For UVc systems click here

Size of a virion

The range of sizes shown by viruses, relative to those of other organisms and biomolecules

To put viral size into perspective, a medium sized virion next to a flea is roughly equivalent to a human next to a mountain twice the size of Mount Everest. Some filoviruses have a total length of up to 1400 nm, however their capsid diameters are only about 80 nm. The majority of viruses which have been studied have a capsid diameter between 10 and 300 nanometres. While most viruses are unable to be seen with a light microscope, some are as large or larger than the smallest bacteria and can be seen under high optical magnification. More commonly, both scanning and transmission electron microscopes are used to visualise virus particles.

A notable exception to the normal viral size range is the recently discovered mimivirus, with a diameter of 750 nm which is larger than a Mycoplasma bacterium.They also hold the record for the largest viral genome size, possessing about 1000 genes (some bacteria only possess 400) on a genome approximately 1.2 megabases in length. Their large genome also contains many genes which are conserved in both prokaryotic and eukaryotic genes. The discovery of the virus has led many scientists to reconsider the contDriedroversial boundavitreousry between living organisms and viruses, which are currently considered as mere mobile genetic elements.

Ultra-filtration units

close up show the membrane bundle

ultra-filtration membrane

close up of membrane filament show the 7 x bores

view of membrane wall

Electron micrographs of viruses

Norovirus. This RNA virus causes winter vomiting disease. It is often in the news as a cause of gastro-enteritis on cruise ships and in hospitals.	Caliciviruses are related to Noroviruses.	Torovirus. An enveloped RNA virus.	Coronaviruses are a group of viruses that have a halo, or crown-like (corona) appearance when viewed under a microscope.
Ebola Virus is a filamentous RNA virus.	Measles virus. This is called a thin section where the virus particle has been cut in two.	Respiratory Syncytial Virus (RSV). In this preparation the ribonucleoprotein can be seen as a herring bone pattern.	Parvovirus B19. Parvovirus B19 is a small DNA virus best known for causing a childhood exanthema called fifth disease or erythema infectiosum.
Human Papilloma Virus	Influenza virus	Transmission electron micrograph of Herpes virus an enveloped virus that looks like fried eggs by negative stain electron microscopy.	TEM micrograph of Poliovirus virions.

Dryden Aqua Ltd Butlerfield  Bonnyrigg  Edinburgh EH19 3JQ  Tel 018758 22222  Fax 018758 22229

Drinking Water Filtration Technology