Alfa Laval Exhibition bus tour

The Alfa Laval UK and Ireland Roadshow, its European exhibition vehicle, started out on the latest tour from their Camberley base last week, and is now in Cork. It returns to the UK with the first stop in Scotland, on 1st September. Main activity in the Camberley factory is the cleaning, refurbishment and repair of the various designs of Alfa Laval plate heat exchangers, plus production and refurbishment of their decanter centrifuges and other separation systems. Heat exchangers now represent 57% of their business, with separators and decanter centrifuges another 22% – but both are large and heavy equipment, so the exhibition vehicle showed smaller units and models, with the main displays concentrating on the fluid handling part of their business. This division represents 11% of sales, and is currently focused on hygienic fluid handling equipment, used in the production of beverages, dairy products, foodstuffs, pharmaceuticals and personal care products.

Supplying equipment to the dairy industry since the 1930s, Alfa Laval fluid handling covers pumps, valves, tank cleaning and mixing equipment and installation fittings to move fluids cleanly, efficiently and gently: many dairies, breweries and pharma plants totally rely on their products, as the range has been expanded to service all the requirements of these customers. The stories on Processingtalk give a good sample across the range: the Optilobe sanitary pump, and their sanitary valve range fitted with the ThinkTop control and monitoring system were well displayed on the Exhibition vehicle, with samples of their tank fittings and cleaning heads.

On a technical note, many of the valve position sensors, such as those used by the ThinkTop, appear to use Hall effect magnetic field sensors. These are typically used in pairs, to allow measurement of the relative strength of the field in two orthogonal directions. This avoids the problems inherent with the large temperature variation of the sensor output, and avoids any aging of the magnet strength in the moving element, by measurement of the ratio of the two fields, effectively monitoring the angle of the magnetic field. The magnets used in the valve stem, or even in a PTFE float in a variable area flowmeter are very small, often constructed from a ceramic material, and potted in place within the sensor itself.

Electrical Arc Flash hazards in the UK

Over the last few months TAS Engineering Consultants have been conducting a UK survey on the safety hazard of Electrical Arc Flash, in terms of risk awareness, assessment and the protection offered to plant personnel. Electrical discharges and contact with electricity resulted in 11 fatalities and 465 injuries in the UK in 2006/7, according to the HSE, so this is an area where hazard and risk assessment is needed. The TAS results are now published*, and of the respondents, 48%, almost half, had not conducted any risk assessment, which is a requirement of the UK regulations (Electricity at Work Regulations 1989). Not surprisingly perhaps, a key driver in conducting a risk assessment was experience of, or knowledge of, an arc flash incident. More training and awareness is needed, and TAS are taking the best approach they can on this topic by sharing best practice, providing in-house training when requested, and creating an Online Networking Site, where best practice can be shared: this also carries a presentation describing the Arc Flash Hazard and shows the results of some incidents.

The TAS summary of their findings is as follows:

The majority of serious injuries and fatalities from electrical incidents can be attributed to electrical arc blast and its associated effects.

Published figures from the H.S.E website state that in 2006 – 2007 there were 11 fatalities and 465 serious injuries as a result of contact with electricity or electrical discharge.

This research was conducted between May and July 2008, with the respondent job titles as: * Electrical Engineers.

* Responsible Engineers.

* Engineering Managers and Directors.

* Environmental, Health Safety and Compliance Managers.

* Corporate Health and Safety Advisors.

* Safety and Operations Directors.

The reason for conducting this research project was due to the fact that there currently appears to be no definitive, single reference point as to the state of the UK industry opinion, activities and future plans relating to the Electrical Arc Flash Hazard.

The key aim was to share best practice relating to the potentially fatal Electrical Arc Flash Hazard with the UK’s professional engineering and safety management community.

The main findings are that training and awareness is required.

59% of respondents identified their future intentions relating to the Arc Flash Hazard is to ‘learn more and put a plan together’.

Therefore, a sustainable and proactive awareness campaign in connection with this potentially fatal hazard needs to be developed on a national basis via service provider professionals, PPE Manufacturers / distributors, publishers, professional membership associations and conference producers.

PPE (Personal Protective Equipment) appears to be the initial and primary choice activity of all respondents, to protect their workers from an incident.

The decision for this could fall into three catagories:.

1) As a cost issue – driven by budget restrictions or purchasing departments.

2) Respondents appear to see PPE as a quicker and easier solution to the problem of protecting staff from an electrical arc flash incident.

3) Understanding of an Arc Flash Incident – it’s causes, and the correct procedure to mitigate the risk.

4) Some confusion currently reigns as American standards make the use of PPE mandatory – PPE should be the LAST line of defence to an arc blast in the UK.

Therefore it is in their professional interest of PPE manufacturers and distributors to make clients and prospects aware of the need to conduct an arc flash study and related systems updates prior to calculating their PPE thermal value requirements to protect their workforce.

Arc Flash Risk Assessment Studies:.

* Almost half (48%) of all respondents have not conducted an electrical arc flash assessment on their current systems (58% if the ‘don’t know’ responses are included).

* Of the 33% of the respondents who have conducted an ‘Arc Flash Risk Assessment’ over the last five years, the key drivers for doing so were – in order:.

* Compliance to UK regulations ( Electricity at Work Regulations 1989).

* USA Head Office / Safety Directive.

* In response to an incident – their own or knowledge from another company.

UPDATING OF SYSTEMS RECORDS.

Respondents appear to place the updating of their systems records as a low priority when addressing a possible arc flash incident – this should be placed as a high priority.

The advised route for Engineering and Safety Professionals to protect electrical workers from an incident is:.

* Conduct a thorough Site Survey.

* Conduct Fault Level Study Calculations and Fault Clearance Times to IEC 60909.

* Identify all Protection Gradings.

* Update all Distribution System records.

* Conduct an Arc Flash Assessment to IEEE 1584 standards – by utilising specific arc calculations software, which will identify calculated levels of flame retardant cal.cm2 PPE equipment required.

* Conduct an assessment before contacting PPE manufacturer / distributor.

* Conduct a Switchgear Risk Assessment to HSG 230 guidance.

* Label and Identify Equipment.

* Contact PPE Distributors / Manufacturers to selected products against the cal.cm2 criteria published in the Arc Flash Study report.

* Develop training and awareness of the Electrical Arc Flash Hazard for staff / operators.

For new build and re-designs of Electrical Switch Gear – it is recommended that remote switching is the chosen option – in order to take the operator away from the possibility of an electrical burn at HV.

TAS OFFERING SOLUTIONS.

As a result and in response to the key findings section 9 – ” Learn more about it and put a plan together for 2008″, TAS Engineering is offering solutions to the UK market in four ways.

1) Findings Update Presentations.

To Share Best Practice, offering the presentation of this research document findings, plus an engineering management analysis and summary of the TAS most recent x 15 Arc Flash projects (across numerous sectors) to companies, conference producers and professional associations.

2) In House Training / Awareness Courses.

An Arc Flash Awareness Course is needed – for all operatives, safety and general management who need to understand the causes, effects and impact of an Arc Flash incident.

Engineering the Risk Out – a technical understanding and guidance course for Electrical Engineers who are looking to conduct their own in house arc flash risk assessments.

3) Online Networking Site.

http://www.electricalsafetyforum.co.uk and http://www.arcflashforum.co.uk.

For peer to peer networking and sharing Best Practice.

4) Electrical Engineers Forum.

Small regional road show / networking forums, with supplier and peer presentations, plus mainly facilitated discussions about the attendee’s current electrical safety issues.

The full article is available on http://www.tas.co.uk/news-pressreleases-story.asp?id=36.

Torque measurement in process plants

Tony Ingham from Sensor Technology reviews torque measurement applications in process plant, and suggests that while meaningful measurements on process fluids and mixtures by process engineers are difficult, torque measurements on the mixers, pumps and conveyors can be used to deduce the state of the process fluid or mixture. An increase in torque on a mixer drive may suggest that a mixture has thickened up as expected, or alternatively that a seal or bearing is failing: either way this is vital information for the process control operator to capture and assess. This introduces the other aspect of torque measurement: because you are actually measuring plant performance, you get to see how the machinery is holding up. Tony provides examples of where torque transducers, easily applied to machinery shafts, are producing useful plant condition feedback – with Charles Austen pumps, in curry processing, in nuclear plant gearboxes and industrial washing machines. TorqSense transducers are also being applied in a food and plastics industry research project at the University of Bradford, to develop a mixing system that monitors the progress of the mix.

Tony Ingham’s review is as follows:

With most machines driven through a rotating shaft, torque monitoring can identify problems before they become critical: Tony Ingham of Sensor Technology explains some of the available techniques….

Say ‘process control’ and most people automatically think of monster-sized central computers running barely-fathomable SCADA software in a control room that would not be out of place at Cape Canaveral.

But out on the plant floor, there may be literally thousands of simple sensors and switches, collecting data and feeding it back to the Beamoth.

These sensors are tracking every little change in the plant operating parameters, which are indicative of either the state the materials being worked or of the state of the machinery itself.

For instance an increase in torque on a mixer drive may suggest that a mixture has thickened up as expected, or alternatively that a seal or bearing is failing: either way this is vital information for the central computer to capture and assess.

Ultimately, process engineers want to transform material from one state to another, and to monitor variables indicative of the various stages of the process.

Some parameters can be measured directly and simply – temperature for example.

Others are more difficult to measure, so an often-used technique is to measure a related parameter (typically one related to the plant or machinery rather then the process material) and interpolate from this.

Significantly many types of process plant – mixers, pumps, conveyors – are motor driven, and measuring the motor output characteristics will often provide process information.

For instance, the torque of a motor could suggest the quantity, speed or viscosity of the process material being worked.

Obviously, measuring the processing efficiency is the primary concern of the production engineers, but torque measurement has a second, equally important function.

Because you are actually measuring plant performance, you get to see how the machinery is holding up.

Knowing what to look for will give you early warning of breakdowns, allowing you to schedule pre-emptive maintenance.

For a continuous process where downtime can cost thousands of pounds an hour in lost production, this can be critical – ultimately the difference between a health profit and a catastrophic loss.

This all sounds very useful, and actually measuring torque can be very simple.

Not so long ago torque sensors required a fairly complicated and fragile array of slip rings connected to the rotating drive shaft of the machine under test.

But now TorqSense provides a digital, non-contact means for taking the readings.

In use, a couple of ‘pads’ are fixed to the shaft of the sensor and a digital TorqSense electronics module unit mounted close by.

The TorqSense then starts monitoring torque, and feeding it as a data signal to the SCADA control system.

PRINCIPLES.

The ‘pads’ contain in fact tiny piezoelectric acoustic wave combs.

The spacing of these combs are designed to open or close under the torque being applied to the drive shaft.

The greater the applied torque, the more the distortion.

The digital TorqSense unit then emits a low powered radio frequency signal towards the combs, which are reflected back to the TorqSense unit.

The reflected signal returns as a changed frequency, the change being proportional to the distortion of the combs, and thus to the applied torque on the drive shaft.

The physical phenomenon which deforms the combs is the result of a Surface Acoustic Wave (SAW), a property first noted in 1885 by gentleman-scientist Lord John William Strutt Rayleigh.

He postulated many possible uses for SAWs, but was unable to realise any practical use for his theories.

It was not until the 1920s that SAWs were shown to be generated by the moving edges of earthquakes and avalanches, the recording of which using low frequency vibration monitors forms the basis of modern seismology and volcanology.

By mid 20th century scientists were creating SAW devices in laboratories and developing new ideas for their use.

As the century closed Sensor Technology were using the phenomenon to develop a new method of digital torque measurement and monitoring, the non-contact nature of which promised to be very attractive to working engineers.

APPLICATIONS.

Charles Austen Pumps (CAP) has recently upgraded its test facilities with Surface Acoustic Wave (SAW) TorqSense equipment from Sensor Technology.

Charles Austen Pumps manufactures pumps individually designed to meet specific customer requirements that cannot be satisfied by off-the-shelf units.

Much of its work comes down to optimising drive dynamics to produce the desired characteristics, be it a smooth flow in a critical medical situation, ultra low noise for pumps in home and office installations, or the guaranteed extra long life of pump in inaccessible locations.

The cyclic nature typical of many pumps operations tends to induce torsional oscillations in the drive shaft, which can have a significant adverse effect on performance if unchecked.

CAP has recently built a new test station based on the Sensor Technology TorqSense sensors, and this is proving its worth time and time again.

Advantages of SAW techniques include a broader signal bandwidth than other analogue based technologies and elimination of electronic interference.

As CAP found, it often also proves far lower cost, simpler to use, is more reliable and has a wider operating range than contact alternatives.

CURRYING FLAVOUR.

Real time process control for food manufacture involves characterising the flow and mixability of highly non-Newtonian fluids.

TorqSense transducers are monitoring the constantly changing flow characteristics of materials as diverse as tomato ketchup, chocolate, pasta sauce and chicken tikka massala, as they are mixed.

Many manufactured foods are presented in a sauce or as what physicists could describe as a neo-liquid and can be produced in a process-type environment.

But to date real time control has been virtually impossible due to the non-uniform nature of the food, which may contain particulates, fibres, vegetables, meat, nuts, raisins, biscuits etc.

To achieve real time control the TorqSense has to be able to detect the changes with sufficient sensitivity, yet be robust enough for general industrial abuse.

Of course it must not compromise hygiene standards and regimes either.

TorqSense has been found to meet all these requirements and is being used by a number of food processors.

Often the key requirement is to mix sufficiently to achieve a uniform dish, but not to waste time and energy by over-mixing.

This can be done by monitoring the applied torque on the mixer shaft, as it will move to a steady state (within the characteristics of the given recipe) once fluid uniformity is achieved.

GEARBOXES.

Nuclear Precision gearboxes supplied to the nuclear industry have to be guaranteed to never fail prematurely, so testing them off-line is a vital function for Centa Transmissions.

A test rig has been developed in which a motor drives the test unit against a load created by an industrial disc brake.

The test runs initially for three hours at the full working load, and is then increased to 300 percent load for another hour.

At the heart of the rig is a TorqSense that constantly monitors the torque in the gearbox, generating a performance profile that can be compared with the ideal performance standard.

The duty the gearboxes are destined for, takes place in an environment where reliability has to be 100%.

They are used in completely automated scoop mechanisms that collect small amounts of ‘high-activity liquor’ from the reactor cooling systems.

This is sealed into thick-walled ceramic flasks for long-term storage until the radioactivity has decayed to safe levels.

This is at the very core of the nuclear plant where a component or system breakdown would mean shutting down all operations for months, automated/unmanned removal of the faulty parts, sealing into a secure flask and automated installation of a replacement.

The cost would be millions of pounds – at the very least.

To avoid this everything has to be lifetime guaranteed to demanding criteria.

MIXING.

A TorqSense is helping analyse the mixing properties of various recipes in a project that could slash development costs in the food and plastics industry, and help nanotechnology advances in the pharmaceuticals world.

Research and development is being carried out at the University of Bradford to develop a miniature mixer (5-25 grams batch) that incorporates a set of integral instruments to monitor the properties of materials as they are being mixed.

The instruments work in real time during the mixing process and their output is captured to a PC for analysis.

Software is being written so that the analysis can be performed simultaneously with the mixing and perhaps even used to interactively control the mixer itself.

One of the key parameters to be measured is the torque of the mixing element, as this will become constant once mixing is complete.

This is measured by a TorqSense non-contact sensor that offers the development team the great advantage of not requiring complex and delicate slip rings, making the mixer easier to build (and rebuild between trials) and far more robust in operation.

The Mini Mixer development and validation is the result of a three year EPSRC sponsored programme of research.

The results of this research are expected to have a major impact on formulation of viscous mixes and scale-up of extruders.

Traditionally recipes for formulating say specific coloured plastics for consumer products are developed in 25 to 50kg batches, mixed in an industrial scale twin screw compounder.

Several batches may be required before the recipe is finalised, so the cost and time involved can be considerable.

Clearly the development of a smaller mixer is advantageous, but the laboratory device must be able to duplicate mixing in the larger scale and guide design and operation of large machines and that is what the research programme has achieved.

That fact that the technology will transfer to the plastic industry and other soft solid sectors means it is likely to rapidly recoup development costs.

WASHING GOES GREEN.

High performance torque measurement is helping to improve the energy efficiency of industrial (and domestic) washing machines.

Process plant manufactures are redesigning their machines to reduce power consumption.

In horizontal axis washers (front loaders in domestic parlance), the load, i.e the wet laundry, is lifted on one side of the axis and falls on the other side.

This is a dynamic, where regenerative energy recovery is very attractive if it can be practically achieved.

A test rig has been built which subjects washing machine systems to extensive tests using an industry standard inverter to simulate the various washing cycles etc.

A critical element of the programme was the ability to make continuous accurate torque measurements, and for this TorqSense is ideal.

The time saving in setting the transducer, compared to installing a slip ring based sensor, over a big project is measurable and significant.

By measuring the torque change the exact moment when to switch the drive from power to regeneration and make the most of the potential energy released by the falling load could be defined.

Given that the motor could be rotating at up to 1500rpm, this called for very accurate data collection and equally responsive control programmes.

This technique has proved so worthwhile that it is planned to build into the next generation washing machines.

With industrial sized loads energy savings of 20-30 per cent could be achievable.

Water treatment systems for power stations

A review of the water purification needed for boiler feedwater has been published by Elga Process Water. The history of power generation in particular is inextricably linked with the development of water purification technology, and vice versa. However, the UK privatisation of power generation has meant a much greater awareness of economic factors, notably the need to maximise the utilisation of assets – so that currently the make-up water treatment plants are generally designed to just meet the normal operating demand of the station: they have become smaller and, instead of custom designed systems, most CCGT stations for example use standard, lower cost “packaged plant”. Elga Process Water has stepped in here to provide a further service, because many of these site installed units may not have adequate purification capacity during periods of high demand, such as commissioning and steam blowing. A temporary reverse osmosis or ion exchange plant in a mobile hired unit from Elga can provide that capacity and is a highly cost-effective option.

The review is as follows.

Back in the 1960s, the then nationalised power generation industry drove boiler pressures, in what were mostly huge, coal fired power stations, ever upwards in an attempt to improve thermodynamic efficiency.

Over the next fifty years on, privatisation and the advent of cheap N Sea gas changed the face of power generation, introducing smaller, high efficiency, combined cycle gas turbine stations.

The history of power generation is inextricably linked with the development of water purification technology, and the changes in the water treatment industry over that half century have been profound.

Thermodynamic efficiency depends on the temperature difference around the cycle, so a higher turbine inlet steam temperature will give better results.

A higher steam temperature means a higher steam pressure, hence the trend towards very high pressure and even supercritical boilers.

Unfortunately, as the boiler pressure increases so maintaining steam purity becomes a problem.

The density of water decreases with increasing temperature and the density of steam increases until, at the critical point (221bar pressure corresponding to a boiling point of 374C), they are the same.

Consequently, as the pressure and temperature increase, phase separation by gravity becomes more difficult and any impurities in the boiler water are likely to be carried over into the steam.

For this reason alone, power station chemists have always sought ultimate purity for their boiler feed water.

The challenge for water treatment engineers was to achieve this purity level, which they did by developing make-up water and condensate treatment plant capable of achieving conductivity less than 0.1uS/cm.

The process route that was developed was ion exchange demineralisation, using a two stage process comprising separate cation and anion exchange resin units, regenerated in reverse flow, followed by mixed bed polishing using cation and anion exchange resins mixed together in the same vessel.

This is still the most widely used scheme for producing power station boiler make-up water.

A bigger problem was that of silica.

Silica is anathema to power station chemists: at pressures over about 40bar it volatilises, passes over with the steam and sublimes from the vapour phase forming a solid deposit on any relatively cool surface.

If the cool surface happens to be the turbine blades the resulting solid deposit can have catastrophic effects on the turbine balance.

The solubility of silica in water increases with increasing temperature and pressure, so the higher the pressure the greater the risk of silica deposition.

Silica dissolves in water forming weakly ionised silicic acid which, in alkaline conditions, dissociates to form silicates: SiO2 + H2O gives H2SiO3, giving H+ + HSiO3- and 2H+ + SiO3–.

Because it is very weakly ionised, the silicate ion is difficult to remove from water and it was not until the development of high basicity Type 1 anion exchange resins that low silica residuals could be guaranteed.

The make-up water treatment plants were large, custom engineered systems generally designed with sufficient capacity to cover for loss of condensate.

This, of course, meant that they were under-utilised for most of the time.

Before the 1980s, power stations generally took their water from municipal supplies but increasing costs and the desire to have independent strategic supplies meant that, many stations adopted their own private water supplies.

This led to the installation of a number of schemes using reverse osmosis.

The process had been developed during the 1960s and 1970s for desalination that is producing drinking water from high TDS brackish and sea water.

Operating pressures were high and the membranes costly.

By the mid 1980s, membrane prices and operating pressures were both falling, and reverse osmosis had become competitive with ion exchange as a first stage demineralisation process at raw water TDS concentrations of about 400mg/l, with the advantage that the process also removed organic matter.

It also produced permeate that could be fed directly to a mixed bed unit, provided that the mixed bed was suitably designed which was not always the case.

Demineralised water from a two stage cation-anion exchange system typically has a pH of about 8.5 and contains about 0.1mg/l of sodium and 0.01mg/l of silica.

The anion load to the mixed bed polishing unit is, therefore, much lower than the cation load, which means that the pH at the exhaustion front of the resin bed is alkaline and, as was noted above, silicate ions remain in solution.

By comparison, reverse osmosis permeate typically contains sodium and chloride ions plus silica and dissolved carbon dioxide.

The anion load to the polishing mixed bed is higher than the cation load and, unless a significant excess of anion exchange resin is provided in the mix, the pH at the exhaustion front is acidic resulting in the potential for precipitation of insoluble, colloidal silica.

More recently the move to combined cycle gas turbine power stations has led to a reduction in boiler pressures to, typically, around 60 – 80bar, and the steam rates are considerably lower than those of traditional steam turbine stations.

Consequently the water treatment plants have become smaller and, instead of custom designed systems, most CCGT stations use “packaged plant”.

These are standard products and, although cheaper in capital cost than bespoke units, may not always have the design features required to meet power station standards.

Many standard two-bed deionisation plants, for example, have similar volumes of cation and anion exchange resin.

Depending on the water analysis this may mean that the anion resin bed becomes exhausted before the cation, and this can result in increased silica leakage at the end of the run, placing a high load onto the polishing mixed bed and putting steam purity at risk.

Privatisation of power generation has meant a much greater awareness of economic factors, notably the need to maximise utilisation of assets.

One result of this is that make-up water treatment plants are generally designed to just meet the normal operating demand of the station.

Consequently they may not be adequate during periods of high demand such as commissioning and steam blowing.

But this is not a criticism.

In fact it has been instrumental in one of the biggest changes in the approach to water treatment over the last twenty years: mobile plant.

The periods of high demand are normally planned, predictable and of short duration.

Hiring in a temporary, trailer-mounted, mobile demineralisation plant is a very cost effective solution for these occasions.

When Siemens Power Generation was commissioning the new E.ON 44MW biomass fired power station in Lockerbie the installed make-up water treatment plant did not have sufficient capacity for steam blowing the SST-800 steam turbine so, in August Elga Process Water supplied Aquamove MODI trailers to provide the additional make-up water needed.

Pre-commission flushing of the Air Cooled Condensers (ACC) was also supported by a novel Elga Process Water MOFI mobile filtration and polishing ion exchange plant.

Ordinarily, ACCs are “flushed to drain” for up to 24 hours, generating huge effluent volumes and wasting vast amounts of irrecoverable energy, before operating in a recycle mode.

The novel Elga approach using a closed-loop filtration and ion exchange polishing system at full flow (140 m3/h at 85C), provided very substantial energy and effluent disposal cost savings in addition to overcoming other logistical issues.

Temporary treatment plant can be rented to cover planned maintenance of make-up water treatment systems, for example resin or membrane changes, and can also be used to handle short term variations in raw water quality.

Such changes are becoming more frequent in mains water supplies as water suppliers switch between sources in order to meet their own distribution needs.

Typically this might mean a change from a surface water source with low TDS to a hard and alkaline groundwater source.

This can, obviously, have major repercussions on the capacity of an ion exchange plant.

A temporary reverse osmosis or ion exchange plant can restore that capacity and, once the raw water quality is back to normal, the mobile unit is returned to the supplier, making it a highly cost-effective option.

Elga Process Water has a range of Aquamove MORO mobile reverse osmosis units and MODI ion exchange systems.

These mobile plants are self contained units installed in standard 40′ insulated trailers with heating, lighting and all necessary safety equipment.

All that is required on site is a connection to the water supply.

The ion exchange units are not regenerated on site: once they are exhausted, the complete trailer is returned to the central regeneration facility, which means zero discharge on site and no problems of handling or disposal of regenerant chemicals.

Pre-treatment, if required, is usually provided in a separate MOFI pressure vessels that can be can be charged with a wide variety of filtration, ion exchange, adsorption or conditioning media.

The simplicity of the concept makes it very versatile, with process options to suit almost any application.

The water purification industry has responded to the changing demands of power station steam raising plant over the last fifty years by developing new technologies and new ways of applying existing technologies.

Capital cost is, currently, one of the main factors affecting the choice of equipment, but cost effective solutions depend on engineering expertise and an in-depth understanding of both the water quality requirements and the performance of water purification technologies under all conditions if generation efficiency is not to be compromised.

Elga Process Water brings together the expertise of three companies – Wm Boby, Permutit and Dewplan – which have served the modern power generation industry for over half a century and which, between them, were responsible for many of the advances in ion exchange technology including air hold down and split flow regeneration, HiPol and SCION short cycle.