Anion regeneration with NaOH: cap a = 0.5 eq/L.Cation regeneration with HCl: cap c = 1.0 eq/L.Residual CO 2 after degasifier = 0.25 meq/L HCO 3 = 2.9 meq/L - a degasifier is recommended.Using the 10 point procedure described above. This calculation is obviously only approximate, as we have taken in point 8 an estimated operating capacity for both resins, not taking into account several parameters that, in reality, affect this capacity: regeneration level, exact water composition, temperature, selected endpoint, etc. If they are too low, reduce the running time t. If the specific flow rates calculated from the resin volumes V c and V a are too high, increase the running time t. For a compact plant with minimum investment cost, use a specific flow rate around 30 to 35 h -1. The specific flow rate in h -1 (often expressed in bed volumes per hour BV/h) is equal to the flow rate in m 3/h divided by the resin volume in m 3. At the end of this calculation, we must make sure that the specific flow rate of both resin columns is compatible with the general recommendations of the resin producer.
The resin volume V required (in litres) is equal to the ionic load divided by the operating capacity :.SAC: cap c = 0.8 eq/L with H 2SO 4 regeneration SAC: cap c = 1.0 eq/L with HCl regeneration or.Consider the approximate operating capaciy of the resins as follows:.Calculate the ionic load per cycle in eq (concentration in meq/L times throughput in m 3):.Using the flow rate f in m 3/h calculate the throughput Q :.Decide about a reasonable running time t in hours between regenerations.Calculate the anion concentration C a : it containsĬl -, SO 4 =, NO 3 -, SiO 2, HCO 3 - or residual CO 2 after degasser if any.
If the bicarbonate content is greater than 0.6 to 1.0 meq/L a degasifier may be justified Here is the procedure for a simple demineralisation plant: