The last decade has seen major advances in Information Technology which, together with improved instrumentation, have allowed a wide range of industrial process control parameters to be measured, monitored, logged, trended and accessed remotely. Whilst this technology has been embraced enthusiastically by many production facilities, it is taking much longer for IT to be accepted in the water treatment field. Part of the reason for this is that water treatment is still considered, by many plant engineers, to be rather arcane. It's all very well to be able to log and trend data but, unless you know how to interpret those trends and when to take action, the availability of the information is not of any great benefit. Now ELGA Process Water has introduced AquatrendTM - a plant monitoring service that puts a water treatment expert on the customer's team, helping plant engineers to get to grips with myths and realities of water treatment.
The way AquatrendTM works is as follows. Firstly ELGA Process Water's treatment specialists work with the customer's plant engineering team to carry out a detailed audit of the water treatment plant, comparing current performance with the original design and future requirements. Then the team identifies and agrees a set of Key Performance Indicators (KPIs) which will be monitored. The KPIs will vary from one site to another depending on what the water treatment plant is used for, but typical KPIs include raw water quality, treated water quality, treated water volume output, wastewater per unit of treated water, resin regeneration or membrane cleaning frequency and so on. For each KPI the team will set a normal or target value, an early warning level and an action level. For example, an ion exchange deioniser may initially produce 1000m3 of treated water between regenerations. As the anion resin deteriorates with age this volumetric output will fall. An Early Warning of resin deterioration may be when the output falls to, say 800m3. At this stage the customer might buy a replacement charge of anion resin which will be fitted when output falls to the Action Level of, maybe, 700m3. But output between regenerations is also affected by raw water quality, so a 20% increase in TDS would reduce the output to the Early Warning level even if the resin is in perfect condition. Organic fouling can also affect capacity. This is why it is so important to have the ELGA Process Water expert on the team - who will be able to identify real resin deterioration from apparent deterioration due to outside influences.
Monitoring can take a variety of forms depending on the customer's preference: electronic data logging, traditional Log Sheets or Statistical Process Control (SPC) Charts for the customer to collect data. If the customer has electronic Data Acquisition or Datalogging facilities then ELGA Process Water can monitor the plant remotely, using telephone or Internet access. However the information is collected, it is reviewed by an ELGA Process Water specialist who reports regularly on trends and provides simple explanations of technical issues and clear recommendations of actions required. There is a "traffic light" reporting system for KPI values - green for Normal, amber for Early Warning and red for Action Required. Depending on the level of service selected, the regular Review reports can be supplemented by regular AquatrendTM review meetings. At the highest level of AquatrendTM service, ELGA Process Water will take over the complete management of the water treatment plant.
Already more than 10 major production sites have signed up for AquatrendTM monitoring services including RWE npower with a paper based data collection system, and both Scottish & Southern Energy and Corus with on-line data collection.
