Soot Glorious Soot!

Since man first started to burn fossil fuels, soot and ash have always been troublesome by-products. With the advent of Victoria Age Britain came a new soot removal system called the ‘climbing boys’. These were young boys who were small enough to climb up chimneys of large houses and clean them from the inside. These poor unfortunates were greatly abused by their notorious employers and as a result suffered from deformed joints, broken bones, burns and various types of cancers as well as sometimes chocking to death by inhaling soot. It was not until 1840 that parliament passed a law forbidding anyone under the age of 21 to sweep chimneys. More information on chimney sweeps can be found on Wikipedia.

The introduction of innovative technologies, such as central heating systems, saw the rapid decline in the use of older, more primitive household soot removal systems such as using either retractable soot cleaners with a circular brush at the tip or sucking the soot down into a cotton baghouse filter, located in the grate. Those employed within ‘Industrial Victorian Britain’ faired no better. Although most did not have to physically climb up the inside of large factory chimneys, nevertheless the huge emissions of soot from such chimneys blighted the lives of the factory workers who lived in cramped terrace housing close by their place of work. They seldom saw the sun and blue skies, instead permanent sooty smog hung over the towns, resulting in the guarantee of an early grave. In the English county of Lancashire alone in 1830 there were some 560 cotton mills, employing 110,000 people, 35,000 of them children who all worked a 14 hour day.

Within the power generation industry, old technologies such as sootblowers are giving way to cleaner, more efficient innovative technologies such as sonic cleaners.

The soot blower can be one of three types – long or short retractable or rotary, fixed position. The cleaning media is usually a mixture of steam and compressed air which seeks to ‘blast off’ the hard deposits which have built up on the boiler tubes, usually an 8 hour shift cycle. The main three problems associated with this older soot/ask removal system are:

1. It relies on high pressure - erosion of the tubes is common which results in loss of boiler performance and high repair costs.


2. This steam/air jet can only reach the area of boiler tube surface directly exposed to the sootblower, allowing soot/ash to still build up and sinter on the non-exposed surfaces.


3. The soot blowers themselves, especially the long retractable type, carry a high maintenance cost.

The innovative solution to preventing soot/ash from building up on all hot boiler tube surfaces whether within the furnace area or later within the superheater or economizer sections is the sonic horn. A sonic horn uses audiosonic sound waves at selected frequencies to prevent the soot/ash from building up on the entire surface of the boiler tubes and without causing any structural damage whatsoever.

So just as innovative technologies moved us from old fashioned soot removal methods within Victorian Britain and in the home, so the same innovative technologies are replacing older systems to improve the overall efficiency of power generation plants worldwide. Read more on power plant cleaning.

Picture shows a sonic horn installed on a boiler to prevent soot/ash build-up.