Where Instrumentation meets TOTEX

December 4th, 2014

AMP 6 is set to be the Asset Management Period where the Water Companies are challenged to make the industry run more efficiently, it is set to be the period where the Capital Solution is not thought of as the first thing to build but a more holistic approach is taken and all options are considered. In short, it is the start of a big change to the Water Industry to operate differently, smarter, more efficiently than it has done in the past.
This is where there is an opportunity for instrumentation to form a part of the solution and this was the focus of the recent Sensors for Water Interest Group Workshop on “instrumentation for TOTEX Efficiencies in Wastewater.” The subject of the presentations centred around three main themes.
•    Producing energy and protecting the assets that are part of the energy production process.
•    Reducing the energy that is used using instrumentation as the basis of control systems.
•    The use of control system to provide better operational control of the treatment works.

The theme around producing the energy starts with the operational control of the treatment works and we saw there was a fascinating presentation about the desludging of primary tanks to get the maximum benefit from the sludge, the main indigenous energy source on site, to the right state for the downstream processes. This continued with presentations on protecting digesters by the analysis of inhibitory substances and protecting the Combined Heat & Power engines by the measurement of Siloxanes, in particular the benefits of the technologies were highlighted showing some startling savings that can be made if instrumentation is used to either protect the process or optimise the way the industry operates.

Taking a holistic approach maximising the products that the industry can take from the wastewater treatment plants including energy & biosolids is going to be a fundamental growth area in the Water Industry. The measurement of the product, something the industry has not necessarily been very good at. is vital to maximising the outputs from this particular area of the business.

The second theme was something that the industry has got very good at and that has been the reduction of the energy that the industry uses. The particular presentation at the workshop was around the use of organic load control to minimise the aeration that is used in the Activated Sludge Process. There are in fact many suppliers who can provide either organic load control or nitrification control and there are gains to be made considering the figure that is usually touted is between 50-70% of the wastewater power consumption. What I felt was missing here is some of the fundamental basics such as Sludge Age control which should come hand in hand with any of these energy reduction techniques and has the additional benefit of managing sludge stocks. The instrumentation is present, the control systems are there and have been implemented by at least some of the Water & Sewerage Companies as the economics are plain for all to see.

The last theme was the use of Control Systems for better operational control of at least part if not the entire treatment works. In fact most of these systems can actually be classed as Advanced Process Control Systems using either instrumental or multivariate techniques to imply the operational state of the treatment works. In this not only can the economic efficiency of the consumables on the treatment works be reduced they can also be tracked and the amount of potential “savings” or “losses” be used to highlight the implications of a way of operation. The fundamental basis for this is of course instrumentation & control.

During the day there were numerous discussions amongst the gathered audience and the main themes that were raised included the understanding of TOTEX and the swing from Capital to Operational Solutions with the bias towards building capital solutions now disappearing and a level playing field being set. This should hopefully allow the greater use of instrumentation to inform decision making and ways of working in the Water Industry moving forward.

The other main issue that was discussed was the need for focused business case centred ways of presenting the benefits of the use of instrumentation and the better use of the data that it produces, the subject of a future SWIG Workshop coming up next April.

At the end of the day it was clear that just in the areas that were discussed on the day, which didn’t include the benefits of instrumentation in the wastewater network, that there was significant benefits that instrumentation can deliver to the Water Industry as we move into AMP 6.

By Oliver Grievson, Anglian Water & Director of SWIG, for WWT January 2015.