Continental Chimney Company: Liner Information
Do smokestacks need to be lined with refractory Bricks?
When do industrial chimneys need a liner?
An industrial chimney liner is a necessary part of every plant or boiler smokestack.
Well maintained liners are designed to protect industrial Chimneys from harmful chemicals and acids that
weaken the outside shell of a brick, concrete, or steel chimney.
Additionally, liners are used to protect your chimney shell from high temperature as well as rapid changes in tempreature.
The reason we say “well maintained” above is because liners sometimes require maintenance or rebuilding.
Though liners are better able to withstand heat and acidic conditions, they are the most fragile part of your chimney.
Therefore, it is necessary to understand the need to regurarlly inspect and maintain a chimney liner to protect the chimney windshield.
Neglected liners have even have been known to collapse.
And there have even been cases where collapsed Liners have brought down an entire smokestacks.
What are the different kinds of brick liner systems used in industrial smokestacks?
Below are some lining systems we inspect, intall, and maintain in industrial chimneys.
Refractory Brick Linings:
Refractory brick liners are designed to withstand high temperatures.
Historically, they have been the first choice in protecting the windshield of industrial brick, concrete, and steel chimneys.
Note the exsamples to the right, where is a photos of refractory brick in a new chimney, and the old standard 4”
refractory bricks in a refinery chimney ready for retirement.
Gunite Flash Coat Refractory Liners:
Gunite Flash Coat liners are often used in industrial radial brick chimneys in what is called a flash coat liner.
Because chimney bricks are very hard and smooth which gives them acid resistance, Gunite flash coats do not adhere well to the
brickwork, holding on mainly to joints in the brickwork after cleaning and joint preperation.
Yet in spite of these problems, some of these flash coat liners have been known to last many years.
Heavy Gunite Refractory Liners:
A typically 3 to 4 inch heavy gunite liner inside a brick chimney can be used to add stability to the chimney.
However, the main purpose of a gunite liner is to protect the shell of an industrial chimney.
Before a heavy gunite liner is installed, the inside of the chimney must be cleaned and anchors attached to hold the
gunite in place. Below is a photo of a very heavy gunite liner that was inside a steel chimney that is being repaired.
Borosilicate Block Linings:
Below is an excerpt from Borosilicate Glass Block Linings at Work in Wet FGD Chimneys By Bruce Luke,
Henkel Technologies and Albert DeKreij, Hadek Protective Systems; From Power Engineering https://www.power-eng.com/news/borosilicate-glass-block-linings-at-work-in-wet-fgd-chimneys/#gref
Many multi-flue chimneys have been constructed using borosilicate block lined steel flues. If desired, the lining can be installed on ground level, before the flue is erected.
Engineers have developed a new chimney to maximize the benefit of this composite technology. The design incorporates the borosilicate glass block lining system directly bonded to the concrete windshield, eliminating the need for a traditional internal independent flue. The design offers the chimney builder and utility owner a potentially cost-effective solution, as well as favorable scheduling advantages.
Borosilicate glass block linings were originally used in the early 1980s when FGD technology was first being added to coal-fired power plants. At that time, most chimney liners were constructed of chemical resistant brick. The primary corrosion protection concerns were horizontal duct sections from the scrubber, as well as bypass ductwork.
Chimneys with brick flues are often severely attacked when placed into FGD service. A borosilicate block lining system can be installed inside a brick flue to prevent deterioration.
Chimney designers evaluated a number of lining types with varying degrees of success. One system used in these early tests was a borosilicate glass block lining, employing a combination of a flexible adhesive/membrane layer and a thick (typically 1.5 inch to 2 inch) lightweight closed cell acid proof borosilicate block, to provide full chemical and thermal protection.
Full height chimney linings using this system were first performed in the mid 1980s—typically to address corrosion problems with existing structures. Over time, the performance of the borosilicate glass block lining system showed it to be a long-term solution. From these early applications, this technology evolved to large scale use today.
Borosilicate glass block lining systems can be used in three applications: construction of new concrete chimneys with steel flues, retrofit modification of chimneys with brick flues and construction of new concrete chimneys without internal flues (new chimney design).
The borosilicate block system is economically favorable as an internal lining for steel chimney flues. The system provides outstanding corrosion protection and it eliminates the need for external insulation. It is suitable for a wide range of operating conditions—wet gas service, reheat and FGD bypass. It also offers several specific technical advantages including minimizing condensate formation, fire resistance and earthquake zone suitability.
The photo below is a borosilicate block system project. As you can see, the blocks are glued to the inside of the concrete, or in this case brick chimney.
Vinyl Ester Resin Linings:
Fiberglass Reinforced Fiberglass Reinforced Polymer Composites have a history of being used in Coal Fired Power Plants.
They are also used in a variety of other applications as well, such as scrubbers, tanks, pipes, ducts.
Qualified Liner Engineering And technicians
Continental Chimney Company has crew members with years of experience with smokestack liners.
For this type of work we do not use rope access techniques.
Typically we use a motorized scaffold is used in smokestacks to access the work areas.
Please give us an oprotuty to discuss with you inspection, repair and lining solutions for your factory, hospital or power plant today.