Original Written By Demi Moore Trump’s mid-east trip is capturing international curiosity and arousing regional intension in Arabian Peninsula. One of the outcomes of USA president’s visit is Qatar was isolated by Uncle Sam’s Arabian allies, amid aviation and diplomatic blocking, except Iran. Though Qatar denied all the allegations to funding radical Islamist, it didn’t make […]
Filter paper is a semi-permeable paper barrier placed perpendicular to a liquid or air flow. It is used to separate fine substances from liquids or air. Filter paper comes in various porosities and grades depending on the applications it is meant for. The important parameters are wet strength, porosity, particle retention, flow rate, compatibility, efficiency […]
Selecting the correct filter paper in laboratory science is dependent upon the requirements involved in the use of the paper. These requirements will determine what type of particle retention and paper grade will be needed. Porosity and flow-rate are two factors that determine the particle retention of a paper. Particle retention is measured in relation […]
Backwashing of the filters is the single most important operation in the maintenance of the filters. If the filter is not backwashed effectively, problems may occur that may be impossible to correct without totally replacing the filter media. These problems could be caused by improper backwashing procedures: Mud Balls Mud balls are formed by the […]
When a filter is subjected to rapid changes in flow rate, the turbidity of the effluent may be affected, and the dirtier the filter media, the greater the effect. When a plant flow changes, the filter flow also has to change to produce the water needed. If an increase is necessary, the flow should, if […]
There are three major types of filter problems. They can be caused by chemical treatment before the filter, control of filter flow rate, and backwashing of filters. Chemical Addition Before Filter Coagulation and flocculation stages of the water treatment must be monitored continuously. Adjustments in the amount of coagulant added must be made frequently to […]
When water passes through a filter, the floc sometimes is torn apart into smaller particles that penetrate deeply into the filter media, causing premature turbidity breakthrough. This requires more frequent filter backwashing of the filter and large volumes of backwash water to be able to remove the floc that has penetrated deeply into the filter […]
When filtration is started after backwash, the filtered water should be wasted until the turbidity in the effluent meets standards. Depending on the type of filter, this may last from two to 20 minutes. This wasting is needed as some suspended material remains in the filter media following the backwash. The media needs to become […]
Proper back washing is a very important step in the operation of a filter. If the filter is not backwashed completely, it will eventually develop operational problems. If a filter is to operate efficiently, it must be cleaned before the next filter run. Treated water is used for the backwash cycle, and is generally taken from elevated storage tanks […]
A UK-based team of researchers has created a graphene-based sieve capable of removing salt from seawater. The sought-after development could aid the millions of people without ready access to clean drinking water. The promising graphene oxide sieve could be highly efficient at filtering salts, and will now be tested against existing desalination membranes. It has […]
