Question

Below is the manufacturing line for cement industry. Determine at which steps, sample quality tests should be placed. State your reason. quarrying limestone crushing limestone raw mill storage and prehomogenization of raw material mining iron ore sand cement process-technology filter preheating pulverized coal clinker storage pulverized coal raw meal homogenization kiln secondary additives calcination-burning raw meal to clinker cooling cement storage cement dispatch bags cement mills bulk bulk bulk/bags

Answer 1

For quality test samples are taken at some time interval like every hour at following steps as follows:

1. Raw material quality test (Placed after quarrying limestone step)

2. After crushing limestones(Placed before storage and prehomozination of raw material)

3. After raw mill(Placed before filter)

4.Before preheating

5.While preheating(Before kiln)

6.Before clinker storage(After cooling )

7.After cement mill (Before packaging)

8.After storage (Before cement bag dispatch)

There are two method dry and wet testing method.This procedure uses X-ray in combination with QCX and QCS blending expert software and this method is short and precise. In addition, the plant has different types of XRF machines which are able to give accurate measurement, detect and control any instrument deviation.Wet method / Chemical method testing this procedure is used in the chemical analysis of cement,freelime, clinker and the remaining raw materials using chemicals and it is also categorized as volumetric and gravimetric.This is process is used for raw material, finished and semifinished products.

Below are available equipment and devices to test & control chemical and physical properties of cement, clinker, raw mix, Coal ,and raw materials.

• XRF machine: to measure elemental chemical analysis within the raw material.
• Differential calorimeter: to measure the exothermic heat value of cement liberated up on hydration in of cement.
• Le-chatlier apparatus: To test and control the physical property of cement soundness which is potential danger of concrete expansion and crack.
• Bomb calorimeter: to measure the gross calorific value /heat value of coal or any other type of fuel.
• Bending and comprehensive machine: to test and control the physical property of cement strength so as to meet the standards.
• Blain apparatus: to test and control the physical properties of cement fineness during finish milling.
• Vicat apparatus: to test and control the physical properties of cement setting time which plays vital role for workability.