What is the process flow of the hydrated lime production line?

The hydrated lime production line is to crush the qualified hydrated lime blocks to a particle size of about 40mm by the jaw crusher, and send them to the hydrated lime storage tank silo through the bucket elevator. The digester performs preliminary digestion. When the hydrated lime completes the primary digestion, it enters into the Ⅱ-level digestion or the Ⅲ-level digester, so that the hydrated lime is completely digested and decomposed, and the qualified hydrated lime primary product is generated, and the digestibility reaches 98%. The design is divided into single-axis, double-axis and multi-axis models).

The digested and decomposed hydrated lime is then sent to the classifier by the semi-finished product screw conveyor, and the product impurities separation and fineness classification are completed by the powder classifier, and the final qualified product after the classification is completed. Warehouses are packaged separately. All polluted nodes of this production line are completed by pulse dust collectors, and the dust collection rate reaches 99.5%.

Hydrated lime production line equipment composition

15T installation site of Weinan Yaobai Cement Plant

Crushing System: Hammer Crusher

Conveying system: bucket elevator, conveyor

Digestion system: Qualified hydrated lime enters the digester for preliminary digestion. When the hydrated lime completes primary digestion, it enters into the secondary or tertiary digester to complete the digestion and decomposition of hydrated lime to generate qualified primary product of hydrated lime with a digestibility of 98%.

Slag discharge system: primary and secondary slag discharge, the slag discharge first discharges the impurities larger than 0.5cm in the semi-finished product, and then the secondary slag discharge discharges the components less than 0.5cm and sand and coal ash.

Dust removal system: Collect the dust generated by the equipment itself, without secondary pollution

Powder selection system: adopt closed circulating air to collect powder

Electric control system: The electric control system of the equipment adopts PLC centralized control, which is mainly used to complete data processing, parameter setting, and directly display the equipment operation status, product quality process control and equipment failure alarm through the computer screen.

Packaging system: including unmetered packaging

Process flow of hydrated lime production line

(1) Raw material storage and transportation

Limestone with a particle size of 10-50mm is transported to the factory area and stacked in the material yard, and the loader is used for the operation of the material yard. The materials with qualified particle size are loaded into the receiving chute set in the material yard by the loader, and the feeder is quantitatively fed under the receiving chute. The qualified particle size is weighed and sent to the top silo of the preheater by the large inclination conveyor. The powder under the sieve is sent to the yard by the 3# conveyor and is regularly transported by forklifts.

(2) Limestone calcination

Limestone calcination is composed of vertical preheater + rotary kiln + vertical cooler, the output is 100~800t/d. The incoming high-temperature flue gas preheats the material to above 1000 °C, so that the limestone is partially decomposed, and then pushed into the tail of the rotary kiln by the hydraulic push rod, and then unloaded into the cooler after being calcined at a high temperature in the rotary kiln, and blown into it by a fan. The cold air is used for cooling, and the material is cooled to below the ambient temperature +60 °C and discharged from the cooler. The air blown in by the cooler enters the rotary kiln as secondary air and participates in the combustion.

(3) Finished product transportation

After the finished lime is discharged from the cooler, it is transported to each finished lime storage by chain conveyor, bucket elevator and belt conveyor. The discharge valve under the lime silo is used to load the lime in the silo into a car or a tanker and then transport it out. Storage bins of different sizes are set up according to customer storage requirements.
The finished product silo adopts circular silo, 2 5~50mm finished product silo, 1 <5mm finished product silo, the capacity of each silo is about 800t;

(4) Flue gas treatment

The high temperature flue gas generated by the combustion of the rotary kiln, after the heat exchange with the limestone in the preheater, the temperature drops below 250 ℃, and then enters the cyclone dust collector for dust collection, and the large particles of dust are collected, and then enter the bag After dust removal, it is discharged into the atmosphere through a high temperature fan, and the dust concentration of the exhaust gas is less than 30mg/m3. A cold air control system is installed at the inlet of the dust collector to protect the dust collector.

The above is all about the production process of the hydrated lime production line. I hope it can be helpful to everyone. When operating the hydrated lime equipment, you must follow the correct technological process.