New Purified Water System
System consisted of a Dual Softener, UV Lights, Ozone Generator and Ozone Destructor, Reverse Osmosis, one 8K Tank and a 6K Tank, a Dual Mixed Bed and a Microza Skid. The challenge was not only to validate the entire system, but also to obtain the optimum parameters at which to run system in order to obtain quality product at the USP and EP level requirements. In order to comply, a series of adjustments had to be made to the design of the purified water system as well.
The first challenge was in terms of the design; the control logic had to be made from scratch. A PLC was installed in order to control pumps at which desired water flow was obtained without compromising water quality.
Additionally, the alarms and control systems of the softener and mixed bed in terms of regeneration, had to be programmed.
During an engineering study it was found that a 40 micron filter skid created a problem in terms of water flow, since it clogged up quickly, creating a problem in water quality. Larger 40 micron filters were installed which resolved the problem. During the engineering study it was also found that Resistivity / Conductivity was too high, creating a problem for the product to be flushed with the purified water. Later it was discovered that it was not the water but the methods used to measure resistivity / conductivity. Therefore, in order to eliminate the problem completely, an online conductivity meter was installed and calibrated. A Gage R&R was performed on such measuring system also.
After all problems were satisfactorily resolved, the PWS was then validated. First an Installation Qualification (IQ) was performed and then an Operational / Process Qualification (OPQ). During IQ, all installed equipment was verified according to manufacturing specs, all instruments that required calibration were verified, all utilities were verified, all preventive maintenance and spare part lists were written and verified against manufacturing requirements. During OQ all alarms, controls and eventful operations were verified. End water quality was also verified to make sure system was capable of providing the quality of water needed at different stages of the system before continuing to the PQ. During the PQ only the end water quality was verified during 3 consecutive weeks in order to make sure system was capable of providing reproducing water quality repeatedly.
An additional engineering study was performed in order to optimize the ozone generator to improve water quality without compromising RO membranes, which could be damaged by too much ozone in water. Therefore ozone amount was increased without going over the quality limit and tested against water quality desired.
All water quality tests were performed by a qualified laboratory and all tests data and analysis were performed by experts. All tests deviations were investigated through a Corrective Action Preventive Action analysis (CAPA) which utilized 6 sigma concepts to resolve all deviations.
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