Abstract
A new innovative idea, which has been filed for patent, is simply utilizing waste water, which is RO membrane reject, in the process of regenerating a softener unit. This unit's product, soft water, is utilized instead of raw water in cooling towers since it has a lower hardness than raw water, resulting in a lower usage of water in the cooling system. The principle of softener units is based on ion-to-ion exchange between the hardness material, which is mainly calcium and magnesium, and sodium. After utilizing the softener unit, the resins will be saturated with hardness materials; hence, a regeneration process would be required to make the unit available again for operation. The new innovative procedure involves replacing the raw water in the regeneration process with RO reject. Theoretically, one of the challenges that the idea encountered was the high concentration of hardness materials in the RO reject. The analysis showed that the performance of the regeneration process when utilizing RO reject will not be affected. Based on the theoretical evaluation, a six-month trial was conducted, and it was concluded that the idea was successful. The quantifiable benefit of applying such an innovative idea is a reduction in the overall utilization of raw water in the regeneration process by 40%, which is 15 million gallons of fresh water per year, which corresponds to a dollar value of $150,000 per annum.
