Hello Everyone
We are facing low pH (9.0~9.2) problem in our both boilers CBD samples since past month. We have one Auxiliary boiler operating at 50~70 ton/hr and one HRSG at 92ton/hr both producing steam at pressure of 39 Kg/cm2 (both boilers are water tube). Demineralized water is being used as fresh make up along with condensate return from Urea and DAP plants as boiler feed water after passing from tray type Deaerator. Amine treatment (ammonia solution) to control pH and Tri-sodium phosphate is being used as scale inhibiter. All other parameters remained normal along with pH of Demin. Water (7.0~7.5), condensate returns (10.1~10.2) and steam produced in boilers (10.1~10.2). There is not any leakage reported from process plants and all four types of condensate returns are none contaminated. Can anyone tell the possible cause and proposed solution of this problem? Thanks in advance.