MANUFACTURE OF LIME Flashcards
What are the main steps involved in the manufacture of lime?
Collection of Limestone: Gathering raw limestone material.
Calcination: Heating the limestone in a kiln to produce quicklime (CaO).
Slaking: Adding water to quicklime to produce slaked lime (Ca(OH)₂).
Collection
Lime stones of required quality are collected Lime stones of purer variety should be used for production of quick lime
Calcination
The fuel required for calcination of limestone consist of charcoal, firewood, coal or coal ashes
Burning of limestone achieve in either clamp or kilns
What is a clamp in the manufacture of lime?
A clamp is a temporary structure used for burning limestone.
How are limestone and fuel arranged in a clamp?
If the fuel is wood, limestone and fuel are placed in alternate layers.
If the fuel is coal or charcoal, limestone and fuel are mixed together and placed in heap form.
Is a clamp suitable for large-scale lime production?
No, it is used for small-scale production.
: What is an intermittent kiln?
An intermittent kiln has a non-continuous supply of heat.
intermittent flame kiln
Intermittent kiln alternate layer of limestone and fuel are arranged
DIRECT LIMSTONE FUEL CONTACT
Intermittent flare kiln
Intermittent kiln in which fuel is placed below arch
flare kilns producing better-quality lime.
NO CONTACT WITH FUEL
Continuous Kiln:
Offers continuous heat supply, where limestone and fuel are fed from the top. It includes continuous flame kilns and continuous flare kilns, with a daily capacity of 4m³ and a fuel requirement of 60 N per 1 kN of limestone.
Slaking Methods:
Slaking to Paste: Quicklime is spread in a basin, and water is added to form a paste, slaking completed in 10 minutes.
Slaking to Powder: Quicklime is broken into smaller pieces, immersed in water, and then crumbles into powder.
