Shetland Heat Energy & Power
The Challenge
The Lerwick Energy Recovery Plant had long struggled with significant slag buildup in the central boiler core – from top to bottom – making it extremely difficult to clean during planned shutdowns.
The cleaning of the boiler center core was performed manually with an air lance and long scraping tools. The cleaning team spent 15 hours to complete each cleaning.
The team was already familiar with Aerovit, as the Aerovit Soot Blower solution had been installed in another part of the facility.
They decided to ask for a possible solution to reduce the hours spent on cleaning and how to improve the efficiency of the boiler.
The Solution
The solution chosen for cleaning Lerwick Energy Recovery Plant was the manual version of the Aerovit SC-Jet Shower Cleaning solution.
By lowering down the nozzle head into the boiler core once a week, the water jets are sprayed onto the hot center core walls to ensure efficient deposit removal.
The laminar water jets maintain their shape and strength over long distances, which ensures minimal turbulence and water dispersion. Upon contact with the hot surfaces, the large water droplets expand instantly by 1,700 times, transitioning from liquid to gaseous form in accordance with the natural laws of physics.
Statement from Lerwick Energy Recovery Plant
Stuart Paton, Plant Engineering Manager:
“….we managed to clean in 30 minutes, the previous shutdown there was about 15 hours of work to clear the centre core build up which was from top to bottom full of slag, so the results so far have been very impressive.
We are saving time, the work is much safer and the negative pressure in the system is better as it is not choked up.”
How does Aerovit SC-Jet Shower Cleaning work?
The Aerovit SC-Jet Shower Cleaning solution is an online system capable of operating effectively at high temperatures. At the Lerwick Energy Recovery plant the cleaning is performed by lowering the SC-Jet nozzle head down into the boiler passes.
Then an optimal quantity of water is precisely sprayed onto the hot center core walls, effectively removing the deposits. This process ensures efficient performance and is executed with precision.
The large droplets penetrate the micro-openings in the fouling and rips off the fouling without requiring additional power or pressure.
Read more about the Aerovit SC-Jet Shower Cleaning solution here.
The result
Reduced cleaning time
At Lerwick Energy Recovery Plant, after installation of the Aerovit SC-Jet Shower Cleaning solution, time spent on cleaning was reduced from 15 hours to 30 minutes.
Improved work safety
With the implementation of Aerovit SC-Jet hower Cleaning, the work at the plant has
become much safer.
Improvements in the negative pressure in the system
There have been impressive improvements in the negative pressure in the system and it is not choked up like before.
Overview
The Lerwick Energy Recovery Plant is placed on the Shetland Islands and provides heat to the Lerwick District heating network. At the Energy Recovery Plant, the fuel used is a mix of combustible household and industrial waste which cannot be recycled.
The waste-to-energy boiler is a 7 MW boiler which were brought into operation in 1999.
Download the case story
Discover how we helped Shetland Heat Energy & Power to reduce time spent on cleaning and improve system pressure.