Efficiency is the name of the game when it comes to gas turbines; you want to optimise your equipment for maximum output. However, if any part of the system becomes dirty, airflow is reduced and efficiency plummets.
Fortunately, maintaining a clean turbine is not that difficult; you just need to understand the dirt you’re dealing with and get the right equipment in place. So, let’s look at the different parts of a gas turbine and how to keep them spick and span…
Parts of a gas turbine
Let’s recap the basic structure of a gas turbine:
- Compressor, which raises the pressure of a fuel gas/air mix
- Combustion chamber
- Expansion turbine
- Auxiliary elements i.e. rotor, filter, bearings etc.
There is potential for any/all of these parts to become fouled, interrupting airflow and reducing efficiency. Even minor contamination has an impact that should not be underestimated.
How does dirt get into gas turbines?
You may be surprised to learn of all the many ways foulants can enter and adhere to the different parts of a gas turbine. Here are just a few examples:
- Airborne foulants e.g. pollution, pollen, salt entering the gas turbine compressor
- Hydrocarbons: a deposit of liquid/oil which attracts particles
- Lubricants
- Residual cleaning products which have not been properly removed
- Salt water causing rust and corroding the blades
- Internal erosion creating its own loose ‘dust’ which further dirties and damages the gas turbine
Once foulants are present, they immediately start causing problems.
What will happen if I ignore contaminants?
Some level of fouling is inevitable but that doesn’t mean you can ignore it. Leaving contaminants to build up within a gas turbine has many effects, some more drastic than others:
- Any contamination will interrupt airflow through the system.
- One knock-on effect is incomplete fuel combustion leading to dirtier exhaust fumes which are terrible for the environment (and your CO2 emissions targets).
- Another knock-on effect is the necessity to burn more gas… and we all know how expensive gas is. Nobody wants to waste this precious resource, let alone eat into their profit in the process.
- As the fouled system becomes dirtier and dirtier, delicate turbine compressor blades and other inner workings become damaged and corroded.
- Eventually, parts of the turbine will cease working altogether and you will face unscheduled shutdowns and costly repairs/replacements.
How do I clean each part of the turbine?
Fortunately, most foulants can be removed from a gas turbine, restoring efficiency and extending the life of the whole system.
Cleaning chemicals
Correct cleaning chemical selection allows the user to target specific foulants and/or remain mindful of environmental considerations. E.g. The FYREWASH® range of cleaning chemicals includes products which are designed for heavy fouling in industrial areas and others which are specifically biodegradable and perfect for offshore use.
Offline washing
When the gas turbine is shut down, the compressor can be cleaned with detergent and deionised water by injecting the cleaning solution into the compressor.
Online washing
It is also possible (and sensible) to carry out regular online washing of the gas turbine compressor. This process is carried out during normal operation by injecting atomised cleaning solution followed by rinsing.
Hand cleaning
Fyrewash 2ipes can be manually used on smaller parts of the compressor during an offline wash.
Where do I start?
The task of introducing or improving cleaning measures can seem daunting, but we’re here to help. At Rochem, we have been in the gas turbine compressor cleaning business for over 40 years. We help customers understand the kinds of contaminants they’re facing and the level of fouling already present. By doing this we can suggest what equipment and specialist cleaning chemicals are best for them.
Our equipment and cleaning chemicals are ideal for both offline and online gas turbine compressor cleaning. We can help in the selection, installation and staff training, ensuring every customer is competent and confident as they reap the rewards of effective, cost-efficient cleaning products.
So, where do you start? Just give us a call!
Get in touch
Our knowledgeable and professional team are here to answer all your questions and discuss how we can help at your gas turbine site. If you want to tackle contaminants, boost efficiency and protect your profits, please get in touch to find out more.