Patent ID: 9670075
Date: 2017-06-06
CPC Classifications: B01J,C02F

Claim:
1. A process to remove nitrates from nitrate contaminated water, which process comprises: passing the nitrate contaminated water through a bed of a strong acid cation exchange resin to remove cations from the nitrate contaminated water to produce an effluent; passing said effluent through a bed of a weak base anion exchange resin in order to reduce nitrate and other anions in said effluent to produce product water; collecting said product water which is lower in total dissolved solids, hardness and nitrates than said nitrate contaminated water; periodically regenerating the strong acid cation exchange resin; periodically regenerating the weak base anion exchange resin by passing a regenerant solution containing ammonia through the bed of said weak base anion exchange resin; rinsing the bed of weak base anion exchange resin after a step of passing the regenerant solution through the bed of weak base anion exchange resin by passing a portion of said product water through the bed of weak base anion exchange resin; collecting the portion of the process water that has passed through the bed of weak base anion exchange resin; mixing ammonia with the collected portion of product water that has passed through the bed of weak base anion exchange resin; and passing the collected portion of process water having ammonia mixed therewith through the bed of weak base anion exchange resin during a regeneration cycle.