Not all filters can remove all types of impurities. Some filters can remove some specific type of impurities from water. But more severe the impurities more costly will be the filters. As a result the overall cost of filters also gets increased. In addition to this, the maintenance requirement of the filters is another point of concern. If any filter is required to be maintained many times a year those type of filter is generally ignored.
But above all the Contaminant Removal Efficiency(CRE) is the most significant aspect of a filter which also encourages and enforces the procurement of filters with the highest CRE. But if it is costly then we generally prefer to purchase a cheaper one compromising the CRE.
Again this consideration can affect the quality of treated water and its use for drinking water. A simple impurity if not removed can cause a massive impact on the overall health..
What is the solution?
Compare the filters with respect to the four main factors as given below :
2)Maintenence Requirement and Cost
3)Cost of Procurement and lastly
4)Type of Filters.
Now by type of filter, it does not implies only one filter. of different types.
It can be one filter or an arrangement of many filters of the same or different types.
However, your job is to select the best one.
Sometimes we get carried out by the very low cost of a filter and compromises quality and consequently the health of us. But if we can implement an unbiased system of decision making then the selection is expected to be non-partial and an optimal one.
That is why at this point of decision making the MCDM techniques can be used which can ensure an objective selection of the best filter arrangements.
The above four((CRE, Cost, Maintenance, and Type of Filter) can be considered as Criteria, and filters or groups of filters which are available for procurement can be selected as the alternatives.
Now using Analytical Hierarchy Process or PROMETHEE or any other MCDM techniques one can select the best alternative and then purchase that filter/set of filters.
Founding and Honorary Editor Water and Energy Journal Publishers
Innovate for Sustainability
and Author of Lecture Notes on MCDM(Indian Link)/Global Link