Soften the ion exchange resin is introduced
water treatment resin is divided into cationic resin and anion resin, and subdivided into sodium cation resin and hydrogen, sodium calcium and magnesium ion exchange resin will water into sodium ions, make water become soft. Hydrogen type resin is calcium and magnesium ion exchange water into hydrogen ions to soften water. Anion resin containing hydroxyl ions are replaceable, can exchange the acid radical ion in water, at the same time using anion resin type and hydrogen cation resin can be water to pure water.
ion exchange in the water treatment industry is the ion in the water and ions on ion exchange resin, such as charge mole amount of reaction.
physical properties of ion exchange resin particle size and the physical properties and performance of its work has very big effect.
ion exchange resin, resin particle size is usually made of small particles of bead, the size of it is also very important. Resin particles is XiZhe, reaction speed is bigger, but by fine particles of liquid resistance is bigger, need a higher working pressure; Especially high concentrated sugar solution viscosity, this effect is more prominent. Therefore, the size of resin particles should choose appropriate. If resin particle size in 0. 2mm( About 70 mesh) The following, can significantly increase fluid through resistance, reduce the flow and production capacity. Eyes on the screen to keep stock to 90% particle can pass its corresponding to the screen hole diameter, known as the 'effective particle size of the resin. The effective particle size of most common resin products at 0. 4 to 0. Between 6 mm.
resin particles uniform whether expressed in uniformity coefficient. It is in the determination of the effective particle size of the resin to keep stock for 40% particles, the screen hole diameter and the corresponding effective diameter ratio. As a kind of resin ( IR- 120). The effective diameter of 0. 4 to 0. 6 mm, it's in 20 mesh, 30 mesh and retained particles respectively on 40 mesh: 18. 3%, 41. 1% and 31. To calculate much uniformity coefficient is 3%, to 2. 0.
c, the density of resin
resin in the dry density is called the true density. Wet resin per unit volume ( Even the space between particles) As the weight of the apparent density. The density of the resin and its degree of crosslinking and the nature of the relevant exchange group. Usually, the crosslinking degree of high density of the resin is higher, the density of strongly acidic or alkaline resin is higher than the weak acid and weak base of rendering, while the density of macroreticular resin is low.
d, resin expansion degree of
ion exchange resin containing a large number of hydrophilic group, contact with water or swell. When the ion resin transformation, such as cationic resin from H + to Na +, Yin resin by Cl - To OH - , because of ionic diameter increase and expand, increase the volume of resin. Usually, the expansion of the low crosslinking degree of the resin degree is bigger. Must be taken into account in design of ion exchange device, dilatation of the resin, to adapt to the production run when the resin volume changes of the ion resin conversion.
e, durability of resin
when resin particles using the change such as transfer, friction, expansion and contraction, after long-term use will have a small amount of loss and breakage, so the resin has high mechanical strength and wear resistance. Usually, low crosslinking degree of the resin is easy to fracture, but more mainly depends on the durability of the resin crosslinking structure of the homogeneous degree and intensity. Such as macroporous resin, has the high crosslinking degree, stable structure, ability and regeneration.
6 cation resin this kind of resin contains a large number of strongly acidic groups, such as sulfonic group - SO3H, easy to dissociation of H +, in aqueous solution is strongly acidic. Resin after dissociation, ontology of negatively charged groups, such as SO3 - , can adsorption in combination with other cations in the solution. The two reaction of cation exchange resin of the H + and solution. Dissociation ability is very strong, strong acidic resin in acidic or alkaline solution can dissociation and ion exchange. Resin in use after a period of time, must carry on the regeneration process, use chemicals in the opposite direction of the ion exchange reaction, the functional groups of the resin reply to the original state, to use again. The regeneration of the cationic resin was conducted with acid treatment, released by adsorption of cationic resin at this time, then combined with H + and restore the original composition.
so we choose resin also want to choose according to water quality and water requirements, so as to get twice the result with half the effort.