In comminution theory, which empirical law states that the crushing energy is proportional to the new surface area created during size reduction?

Introduction / Context:Energy–size reduction relationships help estimate power requirements and select suitable grinders. Three classic laws—Rittinger, Kick, and Bond—apply in different size ranges and fragmentation regimes.

Given Data / Assumptions:

• The question asks specifically for energy proportional to new surface area.
• Applies best to fine grinding where surface area increase is large.

Concept / Approach:Rittinger’s law: E ∝ ΔA (increase in surface area). Kick’s law: E ∝ ln(d1/d2). Bond’s law: E ∝ (1/√d2 − 1/√d1). Thus, only Rittinger directly ties energy to new surface created, matching systems where fracturing creates many fines.

Step-by-Step Solution:Identify law with energy–surface proportionality.Match to Rittinger’s statement.Select Rittinger’s law.

Verification / Alternative check:Fine grinding design commonly references Rittinger for micronization contexts, validating the selection.

Why Other Options Are Wrong:Taggart’s rule: screening/misc. correlations, not energy law.Fick’s law: diffusion, unrelated to grinding energy.Kick/Bond: different functional forms, not directly to surface area.

Common Pitfalls:Confusing Bond’s widely used work index with Rittinger’s fine-grinding emphasis.

Final Answer:Rittinger’s law