Point of Entry (POE) Water Filtration
Your last line of defence in trapping debris regularly and keeping it out of your house’s point of entry is your filter. Because of this, it is very important to use the right filter and operate it as cleanly as possible. Every filter type has its advantages and disadvantages. Which type is best for you depends on your willingness to maintain your filter and its equipment as well as on the clarity you desire and your environmental concerns.
What is a Micron?
Microns are a measurement of one-millionth of a metre. Human hair is roughly 70 microns in diameter. Filters vary in their ability, depending on filter area, water pressure, and the size of particles they can capture. This ability is based on micron size. To trap particles 15-40 microns wide, a filter would require a micron size of 5 microns.
Below is a breakdown of the different types of whole house filters and their benefits:
Sand Filtration System
A sand filter (SF) is a large container of sand that traps dirt and debris as water flows through it. There are two types of sand filters used for the whole-house point of entry. The most common is the high-rate sand filter, which uses sand as the filter medium. The other is a rapid-rate sand filter and uses layers of rock and gravel for support on top of the layer of sand. When water passes through the sand bed, dirt and debris are trapped by the sand grains. Zeobrite may also be used to enhance its cleaning power. It’s a sand filter with 20-grade silica sand that captures particles as small as 20-30 microns.
Advantages:
Sand filters are considered to be the easiest to maintain and operate as well as low maintenance requirements. They may be backwashed when the pressure reads 10 psi over the normal operating level. Various floating particles, deferrisation, demagnisation and ammonia can be removed. A filter media that lasts 5 to 10 years with proper water chemistry is possible with proper water chemistry.
Disadvantages:
However, SF is not very effective against viruses. It will trap algae and bacteria in the longer run. Extra costs can be incurred by treating the disposed water. The filters can clog with slow sand filtration and fine dust in water which is too small to be removed.
Cartridge Filtration
System
Ultrafiltration
Ultrafiltration (UF) is a pressure-driven barrier to suspended solids, bacteria, viruses, endotoxins and other pathogens to produce water with very high purity and low silt density. Ultrafiltration is not fundamentally different from reverse osmosis, microfiltration or nanofiltration, except in terms of the size of the molecules it retains. The pore size in a UF membrane is mainly responsible for determining the type and size of contaminants removed. The smallest particles of any filter are removed, down to 0.01 microns.
Advantages
Ultrafiltration can effectively remove most particles, pyrogens, microorganisms, and colloids above their rated size. It produces the highest quality water for the least amount of energy and it’s regenerable.
Disadvantages
UF is for POU not practical for POE purposes. There are no bacteria or viruses to remove the municipal chlorinated water source. POE of entry is supposed to focus on turbidity. It Will not remove dissolved inorganics.