Question

__________ is used to prepare granules from slip.

• A. Spray dryer
• B. Infrared moisture balance
• C. Filter press
• D. Pug mill

Hint:

Spray dryer converts ceramic slip into dry, free-flowing granules suitable for pressing.

Answer 1

The Correct Option is A

Concept: In ceramic processing, slip is a suspension of ceramic raw materials in water. To convert this liquid slip into free-flowing granules or powder, a drying process is required. Spray drying is one of the most commonly used methods for preparing granules from ceramic slip.

Step 1: Understand what slip means.
A ceramic slip is a liquid mixture containing fine ceramic particles and water. \[ \text{Slip} = \text{Ceramic powder} + \text{Water} + \text{Additives} \]

Step 2: In many ceramic forming processes, especially pressing, the material should not remain in liquid slip form. It should be converted into granules because granules:
• flow easily,
• fill moulds uniformly,
• compact properly during pressing,
• give better green strength.

Step 3: A spray dryer converts ceramic slip into granules.
In a spray dryer, the slip is sprayed as fine droplets into a hot air chamber. \[ \text{Slip droplets} + \text{Hot air} \rightarrow \text{Dry granules} \]

Step 4: Water evaporates quickly from the droplets, and dry spherical granules are obtained.

Step 5: Now check the other options.
• Infrared moisture balance is used to measure moisture content.
• Filter press is used to remove water and form filter cake.
• Pug mill is used for mixing and de-airing plastic clay mass. Therefore, the equipment used to prepare granules from slip is: \[ \boxed{\text{Spray dryer}} \]