Water filter

Worldwide everybody desires pure drinking water. Pure water is obtainable and literally all around us if we want to convcrt the ocean waters with their dissolved salts. Areas such as the Middle East, where fresh water is very scarce, ocean salt water has been filtered by different techniques for the past many decades. PVC and/or RP piping is used to direct the flow of the salt and filter water.

Todate conventional converting systems are wasteful energywise and costwise. Plastic membranes are being used in systems that could go into large-scale water recovery systems from the sea. There is the process called reverse osmosis (RO) where water is separated from a concentrated solution of a salt by a semi-permeable membrane. As an example the DuPont Permasep permeators (Figs. 4.58 and 4.59) has pressure that drives the pure water into the solution for dilution. The driving force is the concentration gradient and it is in the form of a pressure that is related to the difference in the vapor pressure of the water and the vapor pressure of the solution at the temperature at which the process takes place. By applying a pressure greater than the osmotic pressure to a solution, the direction of flow of the water is reversed and pure water is removed from the solution.

These permeators come in different product types that are used

: Water filter through system (Courtesy of DuPont)

Ann-Telescoping Device

Tncot Pro Waier Colli Chann<

Feed Ch¡ Spact

Product

Ann-Telescoping Device

Tncot Pro Waier Colli Chann<

Feed Ch¡ Spact

Product

Bnne Seal Carrier

according to the type of water to be treated. There is seawater and brackish water. Brackish water is lower in salinity than normal salt water and higher in salinity than freshwater, ranging from 0.5 to 30 parts salt per 1000 parts water located between sea water and fresh water.

Different recyclable scrap plastics (PE, PP, etc.) can be made in what is usually called plasdc lumber that is take off from wood lumber. To increase their mechanical properties short glass fibers (as low as 3wt%) are added to the recycled plasdc resulting in doubling strength. Most are extruded into boards and other shapes. Another process used is injecdon molding. Fabricated products compete with wood lumber on land and particularly in the water (fresh, brackish water, and saltwater). Uses includes bridge decks, boat docks, pallets, outdoor furniture, and so on. Compared to wood advantages exist such as being relatively maintenance-free for at least half a century, as opposed to 15 years for treated wood and 5 years for untreated wood. Todate the major disadvantage has been cost. Extensive use is made in applying plastics in wood to improve their structural and decorative properties (compreg,

Plastic lumber are now available in stores such as Home Depot Inc., USA Plastic Lumber Co. (Boca Raton, Fl), Loewes, and Menard who

0 0

Post a comment