Gas producer operation — causes of excessive clinker formation Excessive clinker formation in gas producers occurs primarily due to which factor(s)?

Introduction / Context:
In gas producers and fixed-bed gasifiers, clinker is the fused agglomerate of ash that obstructs airflow, disrupts bed permeability, and degrades gas quality. Understanding clinker causes helps operators select proper fuels and operating conditions.

Given Data / Assumptions:

• Ash composition and fusion temperature influence melting behavior.
• Fuel sizing (fines content) affects bed permeability and temperature distribution.
• Hot spots arise from maldistribution of air or erratic reactions.

Concept / Approach:
Clinker forms when ash softens or melts and then sinters into lumps. Low ash fusion temperatures mean melting occurs at typical bed temperatures. Excess fines increase resistance and create localized overheating. High gasification rates and hot spots accelerate ash softening and fusion.

Step-by-Step Solution:
Assess fuel properties: high ash and fines increase risk.Check ash fusion temperature: lower values promote early melting.Evaluate operation: hot spots and high rates drive local temperatures above ash softening points.Combine: all listed factors contribute significantly to clinker formation.

Verification / Alternative check:
Operational guidelines recommend controlled bed temperatures, proper sizing (screened coal), and choosing fuels with suitable ash fusion characteristics to reduce clinker.

Why Other Options Are Wrong:

• (a), (b), or (c) alone capture only part of the picture; clinker is often multifactorial.

Common Pitfalls:

• Ignoring ash chemistry; two fuels at the same ash percentage can behave very differently.
• Overlooking air distribution and grate conditions that create hot spots.

Final Answer:
All (a), (b) and (c)