Some raw feed waters contain suspended particulate material. This material is commonly sand, iron oxides, clay or elemental sulfur. Introduction of such materials into the membrane system can cause the development of excessive system differential pressure (dP), or even complete blockage of the brine channels with the resultant reduction of permeate flow. It can also cause physical damage to the membranes themselves. This usually results in a decrease of permeate quality and reduction of membrane life. Cartridge filtration is normally a simple and cost-effective way to reduce the amount of particulate matter reaching the membrane surface.
Membranes are loaded from the feed end of the pressure vessel. To better understand the installation procedure, the following definitions are helpful:
Much of the environmental discussion of the new millennium has been centered on an individual’s carbon footprint. From running the shower to the continuous flow of the faucet as you brush your teeth, we have all heard statistics regarding how much water we use. Similar to our carbon footprint, we can estimate our individual water footprint.
Whether commercial or residential, the modern world is currently seeing an increase in water reclamation practices. Reclaimed water, perhaps better described as "recycled water," is wastewater that has been filtered and treated for reuse, thereby limiting the need for fresh water use. This practice has increased in popularity over recent years. GAO reported 36 states as using reclaimed water in 2013, compared to just 23 states in 2003.
An important part of operating membrane systems is accurate data collection on a daily basis. The data will help predict normal maintenance schedules and will help determine the cause of any system upsets. Comprehensive data is very useful in determining when the membranes need to be chemically cleaned, or eventually replaced. It also alerts the operator to changes taking place such as fouling, leaking “O” rings etc.
There exists a potential for calcium, barium, strontium, fluoride and silica compounds to precipitate in the concentrate or brine channels of the reverse osmosis membranes. Precipitation occurs when the solubility limits of these various salts and silica is exceeded.