May 2019

analyser being used and its application, consider changing parts such as tubing, measurement cells and seals and diaphragms on a yearly or bi-annual basis. Recommended frequency Given the diverse range of parameters that are measured in water and waste treatment processes, it is difficult to set a universal rule when it comes to setting the frequency of maintenance checks. In most cases, it is possible to create a maintenance routine by monitoring the nature of past breakdowns with any issues that have been recorded, such as fouling, abrasion or measurement variations. By using these as a guideline, it will then be possible to create a maintenance routine that can help to safeguard against future occurrences. In addition, information from the device manufacturer should also be taken into account in order to further optimise performance. Consider the lifecycle Another factor that can affect the way that an analyser is maintained is where it sits in its lifecycle. This should take into account the model, age and make of the analyser. Models that are at the start of their product lifecycle will be well-supported, with ready spares availability. This may differ for models from older product ranges, where spares and the expertise to service them may not be as readily available. Dealing with reputable manufacturers can help to minimise this, as they are more likely to be able to support older products or else to recommend a suitable upgrade path with an alternative replacement. The important role played by continuous water quality analysers in safeguarding the quality of both potable and treated waste water makes it critical to ensure they are kept in top working order. With water quality analysers being very much on the front line of every water treatment process, the need to ensure they are kept in good working order is of paramount importance in order to avoid any penalties arising from a failure. Following the steps outlined in this article will provide a useful starting point for helping to design an effective maintenance strategy and prolong the life of continuous water analysers. reagents, with potential failures arising if the reagents are not fitted properly, if tubing is blocked or restricted or if the reagent lines were not properly primed. Failure of a routine calibration can also be symptomatic of issues within the analyser, such as blocked tubes and valves, leaking seals or contamination of the reference standard. Check the sensor It is worth checking analyser systems that are in direct contact with the process, as sensors can become obstructed or damaged as they often bear the brunt of any adverse conditions. In waste water treatment processes in particular, sensors can quickly become fouled by the build-up of organic matter or subjected to abrasion by sediment. The accuracy of electrochemical sensors used in dissolved oxygen monitoring applications, for example, can quickly become impaired due to fouling of the sensor membrane. Replacement of components Follow the manufacturer’s recommendations regarding the replacement of any key components. Depending on the type of 36 | Plant & Works Engineering www.pwemag.co.uk May 2019 Energy, the Environment & Water Focus on: Water & Waste Management xpertise... e ol tronc umidity H e aintenanc M e & Servic umidifiers H diabatic A ehumidifiers D umidifiers H team S onment. vir the ideal en eate to cr ... o solutions.c .humidity www a onsult & c ye e surv FREE sit • ojects pro t alue dds v A • up al back echnic tull F • a o suit all applic tt quipmen E • Design & support • .uk tion tions c eir atce dir hguorht % 0 9op t e uvaS .gniol co co e |68501 84821 0T: coe@sela s |ku. inloo ceivatropav g s tos y cgrenn e i g o u.co.niol co k gnilooe ccapf s t ous oserte she tka egdelwong knidael-yrtsudnf i s orae 15 y We t T: 01284 810586 | ecocooling.co.uk . .