Product Details Supplier Info More products

TLV Euro Engineering has revealed five steps that industrial businesses can take to improve their steam plant efficiency.

In many industries, steam plant now provides a crucial energy source, delivering reliable high-quality steam for the production process.

However, rising gas prices and a need to reduce CO2 emissions has led to an increasing focus on the efficiency of steam plant.

While there are many ways to improve efficiency they often involve considerable investment (for example, a wholesale change of steam traps), so before embarking on any large capital project, it is worth taking a closer look at the system itself by following five steps to improve efficiency.

Before you begin, however, it is a good idea to get an idea of the cost of steam generation.

All the calculations quoted here are based on a plant running 24/7 for 50 weeks a year, with a steam cost of GBP20.00.

For the best results, you need to attain the steam cost for your site.

Approximate steam costs can be calculated easily by taking the fuel costs and calorific value and applying a rough figure for boiler efficiency.

For a more accurate approach the amount of team generated, fuel costs, water costs, water treatment costs and also boiler maintenance costs can be taken into account.

First, a steam trap survey can easily identify leaking or faulty traps and provide significant potential savings.

For example, it is not unusual for a site with 100 steam traps to find 15-20 are leaking.

A leaking steam trap could be losing you up to GBP2,000 per year, so the potential annual loss – and therefore the potential saving – is in the region of GBP35,000.

Replacing the traps could provide payback in months rather than years.

The same survey will also identify blocked traps, which can significantly reduce process efficiency, affect steam quality and impact on the safety of the system.

In a recent example, TLV Euro Engineering was contracted to provide regular steam trap surveys using its Trapman TM5 testing equipment at all 13 UK-based BOCM Pauls animal feed sites.

To gain ISO14001 accreditation, each site needed to monitor energy usage to improve efficiency and reduce energy.

TLV was asked to carry out a steam survey to not only determine whether a trap is working correctly, but also accurately quantify the steam losses in traps that are leaking.

A total of 552 traps were tested of which 89 (16 per cent) were leaking, which was estimated to be costing BOCM Pauls GBP95,000 and 435 tonnes of CO2.

Second, as the cost of steam rises with the increase in energy prices, so does the value of condensate.

Calculating the value of condensate needs to take into account heat energy, water charges, the cost of water treatment and effluent charges.

Based on typical costs of GBP3.00 or GBP4.00 per tonne, a small steam-powered process discharging 1,000 litres of unrecovered condensate per hour would be costing approximately GBP24,000 per year.

In contrast, the savings made by the installation of an efficient condensate return system with associated pipe modifications, could result in a payback of less than six months.

Third, although the cost of insulation can be high, the potential savings can deliver a rapid return on investment and programmes are available to calculate the standing losses from un-lagged steam pipes.

All that is required to establish a realistic estimate is a simple site survey to identify the size of pipe and the steam pressure.

To quote an example of the benefits: 10m of un-lagged internal pipe; a steam pressure of 10barg; an ambient temperature of 20C; and a process running 24/7 can lose as much as GBP4,500 per year.

Fourth, a 1mm hole in your steam main could be costing GBP500 per year.

A 2in isolation valve with a leak from the steam could be costing GBP750 per year.

So, if you think highlighting steam leaks is obvious, walk around your steam system and take note of any leaks from valve stems, safety valves, flanges and unions.

You will probably be surprised how many you find.

Finally, steam metering itself will not directly save energy, but for good housekeeping it is an essential discipline.

Metering from the boiler house provides the most accurate steam consumption statistics for a typical working day, and can also be a useful troubleshooting tool.

For example, a rise in oil consumption without a corresponding rise in steam production can point to a problem with the boiler.

Potentially, there are thousands of pounds worth of savings to be made by following these five simple steps.

For the best results you may need the help of a steam specialist company, but elements of a preliminary audit can be carried out in-house.

Based on the findings, a programme of work can be identified to improve the system and realise some serious improvements.

Having brought your steam system up a level in terms of efficiency, it can become more difficult to find opportunities to save energy.

The next stage may be a larger project with a greater capital outlay, but there may be large savings to be made.

Venting large amounts of flash steam to atmosphere can be a considerable energy loss.

Recovering and using this steam can result in a significant saving.

If you have a process running at 1 to 1.5 barg, you may be able to utilise the flash steam for this application, but care needs to be taken to make sure that the requirement for the flash steam is in line with the flash being generated.

If you do not have a suitable use for the flash steam, there may be opportunities to use it to preheat boiler feedwater.

Alternatively, a steam compressor uses plant steam mixed with flash steam to generate steam at a more useful pressure.

Improved boiler operation can in turn show a marked improvement in efficiency.

Regular servicing and maintenance; correct blow-down; the use of modulating burners instead of traditional on/off burners; and sequencing systems for multiple steam and hot-water boiler installations can all help to maximise boiler efficiency.

In addition, variable-speed drives on the blower and an economiser to utilise waste heat in the flue gas can also help to increase the efficiency of the boiler.

Finally, look at the way steam is used around your site, as steam pressure and quality can have a significant bearing on the efficiency of particular processes.

TLV was founded about 50 years ago in Japan and is now a recognised global leader in steam engineering and still family owned. From its UK headquarters in Cheltenham, the company offers a wide range of steam engineering products supported by services such as consulting, site inspections and seminar training.

TLV (the name derives from ‘Trouble Less Valve’) has always strived to manufacture innovative, high-quality, long-lasting steam engineering products and systems and one of its early successes — the A3 steam trap — was awarded no less than seven patents. This steam-heating, condensate-cooling, double-jacketed, thermodynamic steam trap is unaffected by ambient conditions and offers an incredible 10 times the durability of previous products.

TLV now designs and manufactures a wide range of products and systems such as the award-winning CV-COS, an electro-pneumatic pressure-reducing valve with a convenient control function; and the Vacuumizer, a vacuum pressure steam heating and cooling system.

TLV has also revolutionised fluid control technology with the launch of its patented ‘Free Float’ steam traps, which, with only one moving part, guarantee long life and reliability.

View full profile