Without some form of cleaning, deposits of calcium carbonate and metal ions will build up on the quartz sleeves of the UV lamps in a ballast water treatment system. This will impair treatment, since less of the UV light produced by the lamps will be able to pass through.
Mechanical wiping is an alternative to CIP, but wipers are ineffective against the build-up of metal ions, which must be removed with a low-pH fluid. Nor do they clean the UV sensor within the reactor, which measures the UV transmittance. If the sensor and quartz sleeves are dirty, the system may use more power than necessary or be otherwise poorly controlled.
Any form of mechanical cleaning – including manual cleaning – will also lead to sleeve scratches. Eventually, these too will degrade the treatment performance.
Simply put, tests have shown that CIP has a valuable role in maintaining the biological disinfection performance of a ballast water treatment system. In a UV-based system, the effects are noticeable after a single cleaning operation. Moreover, by reducing energy use and maximizing the lifetime of the quartz sleeves, CIP has a long-term role in keeping operating costs down.