sign in a cave in Laos

27 July 2012

Lime kilns in Perak, Malaysia

Last week I had an interesting visit to some old fashioned lime kilns in Perak, Malaysia. The kilns are used to make quick lime.

Quick lime is produced by heating limestone. Today most companies use state-of-the-art high tech modern lime kilns to make the quick lime. However in Perak there are still some old fashioned, cottage industry type lime kilns.

Limestone is CaCO3. Quick lime or burnt lime is calcium oxide (CaO). It is white, alkaline and crystalline. It is made by the thermal decomposition of limestone in a lime kiln. It needs to be heated above 825°C .

CaCO3 + heat = CaO + CO2

In the Bercham area, north of Ipoh in Perak, Malaysia, there are still working lime kilns. There are 2 rows of kilns.
The open area in front of the kilns housed the logs for burning, quick lime stones and bags of the finished product, the quick lime.

There are 3 kilns in a row. A short tunnel leads via a low access arch to a circular brick lined kiln. The brick work was amazing. Such orderly patterns. The fire bricks looked smaller than normal house bricks.

The shafts seem almost circular. The arch in the second kiln was made of red bricks.

Men carefully stack the limestone at the bottom of the kiln, building up the domed layers, which gradually slope in, with a timber centre. Once the layers meet in the middle they can then throw down more limestone from the top.
Air has to pass freely to provide combustion and the layers need to maintain their shape throughout the burning process to avoid collapse. Wood is used to produce the heat. Excessive temperatures product unreactive "dead burned" lime. Extra wood could be fed in through the access tunnel. Lumps of CaO fall to the bottom.
The arch in the third kiln -


The process is quite slow -
5-6 days to stack the kiln
1 week to burn
3 days to cool
remove the lime on the next day.

We went up to the top to see the loading area.
This photo is looking straight down -
Piles of limestone waiting to be used
and reject quicklime that has not burnt properly

UPDATES
These kilns stopped working sometime in 2013.

See blog on more lime kilns in Perak, at Gunung Panjang. These kilns have been abandoned for some time.

© Liz Price No reproduction without permission

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6 comments:

  1. You look like a Greek Kore...:-)
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  2. Very interesting!
    Do they load the kilns from the top or through the entrance tunnel?
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  3. They start loading from the bottom, building up the layers which gradually slope in, till they meet in the middle, then when they've reached a certain height, they add the rest of the stones from the top.
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  4. My relative lives in Bercham Garden. I didn't know anything about this. What is it for anyway ?
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  5. To make lime, which is used in a lot of industries , for building and engineering materials , waste water treatment, etc.
    ReplyDelete

3 comments:

  1. Liz,
    I remember i ask you about the Japanese Carbide chimney of Malim Nawar a long2 time ago
    and i didn't know you have a blog.
    Perak still have many secrets to discover,
    can you pint point some landmark nearby so that i can find this place?

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  2. Maybe that was on my Multiply site, which has now closed down. I have a cave blog and also a non cave blog !
    Kilns are off the road from Bercham to Tj Rambutan. Do you use Google Earth?

    ReplyDelete