How to improve gas turbine uptime with gas turbine cleaning

The more efficient your gas turbine is, the greater your financial profit. So, if someone said there was an easy way to improve the efficiency and uptime of your gas turbine, you’d want to pay attention.

Amazingly, cleaning the compressor can improve the efficiency, reliability, and possible uptime of your gas turbine. And the best part is that it’s easy and cost-effective, too.

How does fouling affect efficiency and uptime?

Under normal use, the internal blades of gas turbine compressors become coated with foulants. Salt, hydrocarbons, wax, and all manner of microscopic impurities inevitably enter via the air and, under high pressure and temperature, become fused to the compressor’s surfaces.

The presence of these foulants causes several problems:

• Interrupted airflow
• Reduced air mass flow
• Erosion
• Corrosion
• Higher emissions
• Blocked hot-section cooling passages
• Eventual failure of the compressor

Foulants stop air and gas flowing through the compressor as they should, leading to less efficient combustion. This means less output and more emissions than you could achieve with a clean, efficient system.

Eventually, if left unchecked, the compressor will stop working altogether, leading to expensive downtime to carry out emergency cleaning and repairs.

How does cleaning improve gas turbine efficiency and uptime?

Keeping your gas turbine compressor clean avoids all the problems above. Efficient airflow is maintained, gas combustion is optimized, and unnecessary downtime is avoided.

There are, however, different options when it comes to cleaning, and each has its merits.

What are the different cleaning options?

There are three main options when it comes to gas turbine compressor cleaning:

On-line washing

This method involves spraying atomized detergent and/or water into the compressor via specialized nozzles during normal turbine operation. There is no need to shut down the turbine, and there is no impact on workload.

Off-line crank washing

As the name suggests, this cleaning method is carried out when the turbine is offline and sufficiently cooled. Using the same equipment as online cleaning, wash fluid is injected into the compressor while the turbine slowly turns. This cleaning method is more effective than online cleaning but does require shutting down the turbine, which is time-consuming and costly in terms of lost profit.

Off-line hand washing

The final cleaning method is manually cleaning the internal surfaces of the compressor while the turbine is shut down. This allows for a thorough, clean, and up-close visual inspection of the equipment.

Which is the best gas turbine compressor cleaning method?

While the different cleaning methods vary in their thoroughness, they are each important and should all be used within a cleaning strategy. It is difficult to pick the ‘best’ method, as they support one another to maintain an efficient compressor and avoid unscheduled downtime.

How to develop a gas turbine cleaning strategy

Online washes are perfect for regular cleaning, e.g., every week or even every day, and minimize the need for downtime. They keep fouling in check without impacting performance while they are being carried out. However, they can’t get rid of some really stubborn residues. That’s where the offline washes come in.

Off-line crank washing or hand washing should be carried out during any scheduled downtime to make the most of the opportunity to give the compressor a good clean.

There is no single cleaning schedule that will work for all sites: there are too many variables. Different physical locations have a huge impact on the level and types of fouling and will require a different combination/frequency of on and off-line washes. You will learn when thorough cleans are required by noting a drop in efficiency or physically seeing fouling. This knowledge can help inform your cleaning schedule.

Do I need fitted cleaning nozzles?

The short answer is ‘yes’. Specialized fitted compressor cleaning nozzles:

• Facilitate on-line and off-line washes with the same equipment, minimizing foulants and maintaining an efficient gas turbine compressor.
• Enabling online cleans allows for minimal downtime that would otherwise be necessary for cleaning.
• Inject cleaning fluid at a specific, measured droplet size optimized for cleaning (without causing damage).
• Utilize a specialized spray pattern for a thorough, reliable clean.

While you don’t technically need cleaning nozzles to run a gas turbine, without them, you are wholly reliant on off-line hand washing to maintain your compressor, which is less convenient and more costly than the alternatives.

Fortunately, cleaning nozzles can be retrofitted in most cases.

What detergent should I use?

Choosing the correct cleaning chemical will make a huge difference to the cleanliness of your compressor. It’s essential to use a specialized product to avoid potentially causing more harm than good and to ensure the best results possible.

In our industry-leading FYREWASH® range of detergents, we offer a full range of products for different situations. Whether your priority is tackling heavy fouling, minimal environmental impact or you require a low-foaming product, there is the perfect detergent for every situation.

We are here to help you choose the right product for your specific site.

Is turbine cleaning worth the cost?

Even with purchasing detergent and installing any necessary equipment, maintaining a thorough, regular gas turbine compressor cleaning schedule saves significantly more money than it costs.

By making combustion more efficient and avoiding unscheduled downtime, many customers easily recoup their expenses multiple times while also extending the lifespan of their equipment.

Get in touch

We hope you’ve gained some ideas on how to improve your turbine’s efficiency and uptime through cleaning and are here to help if you’ve got any questions. With over 40 years’ experience is this specific part of the industry, we love helping customers improve their systems and are happy to lend our expertise. Please get in touch to find out more.