DEVICES IN PRODUCTION
LIME KILN
DEVICES IN PRODUCTION
Purpose
The Lime kiln is designed for limestone burning and products are: the lime and exhaust
gases containing carbon dioxide. Limestone burning takes place in completely enclosed kiln
shaft. The whole process control of limestone burning such as; temperature measurements
in various zones of the kiln, exhaust gas temperature measurement, temperature measurements of extracted lime make the process of limestone burning completely safe. Lime itself
and and its dust are non-combustible and are inexplosive products.
Description of operation
The raw product for lime burning is limestone containing CaCO3. Under the influence of heat
the limestone decomposes to lime and carbon dioxide: CaCO3 + 43,3 Cal CaO + CO2.
Heat is generated thanks to the combustion of coke, which is feed to the furnace together
with limestone. Kiln charge is feed from the top and air by blowing nozzle from the bottom.
The raw product is heated up over the firing zone by hot exhaust gases. This area forms a
heating zone. In the part of the shaft, below the firing zone, the lime is cooled in a stream of
injected air. This area forms a cooling zone. Burnt limestone- lime- discharged from the bottom of the kiln.
The mechanisms installed on the furnace are used for:
• feed charging
• kiln discharging
• flue draft
The performance of all mechanisms is managed by the control system. Skip of the inclined
conveyor is loaded by mix; stone-coke. Payload is discharged on a top of the kiln to the hopper of upper closure. After appropriate activation of mechanisms of the upper closure the
feed falls to shaft of the kiln. Automatic charging of the kiln continues until a command- kiln
full.
After the time required for burning of single charge of limestone the automatic switching on
of the vibratory feeders takes place.
Lime is discharged to under the kiln lime tank and than by lime discharging system is directed outside. Entire flue gas-saturated gas- is drawn and transported in closed ducting of
controlled pressure to the sugar juice purification station
DEVICES IN PRODUCTION
Technical features
TYPE
Working capacity of the kiln
Working height of shaft
Outer diameter of refractory lining
Total height of kiln
Weight of steel part of the kiln
Weight of refractory lining
Power installed
Temperature of drawn exhaust gas
Temperature of discharged lime
Temperature of shell
Shaft type, pressurized, on the steel skirt
200 m³
25 m
4620 mm
42,6 m
135 ton
290 ton
75 kW
60 – 120 o C
max 60 o C
max 50 o C
250 m³
25 m
4870 mm
45,7 m
160 ton
302 ton
105 kW
60 – 120 o C
max 60 o C
max 50 o C
Guaranteed operational parameters of the kiln
200 m³ Lime kiln
Nominal CaO output – 110 t/day
Maximum CaO output – 135 t/day
Minimum CO2 content in the kiln gas – 32%
Lime milk Ca(OH)2 – 20 ÷ 25 Be
Coke consumption – 7,5% per limestone
Noise level not higher than – 55 dB
250 m³ Lime kiln
Nominal CaO output – 120 t/day
Maximum CaO output – 160 t/day
Minimum CO2 content in the kiln gas– 32%
Lime milk Ca(OH)2 – 20 ÷ 25 Be
Coke consumption – 7,5% per limestone
Noise level not higher than – 55 dB
Above specified parameters are applicable for the limestone of 80÷120 mm granulation and
min. 96% of CaCO3 contents, MgCO3 max. 1,5% and SiO2 max 1%, contents of Al2O3 + Fe2O3
max. 1% and NaCl max. 0,1%, as well as 40 - 70 mm coke granulation and of 29000 KJ/kg /
7000 kcal/kg/ calorific value, max. – 5% ash contents, – 1% sulfur.
DEVICES IN PRODUCTION
ŚWIDNICKA FABRYKA URZĄDZEŃ PRZEMYSŁOWYCH ŚFUP Sp. z o.o.
ul. Wincentego Witosa 4, 58-100 Świdnica, Poland
tel. +48 74 64 99 100, fax +48 74 640 20 01, e-mail: [email protected], www.sfup.pl