Solid waste pre-treatment in municipal wastewater engineering: Which ONE statement about screenings handling is NOT correct?

Introduction / Context:
Screenings handling is one of the first steps in municipal wastewater treatment. Coarse materials such as rags, plastics, and debris are intercepted by bar screens and must be handled and disposed of safely. This question tests your understanding of terminology and standard disposal practices for screenings in environmental engineering.

Given Data / Assumptions:

• We are dealing with screenings from preliminary treatment.
• Standard options for disposal include incineration, burial, and controlled dumping depending on local regulations.
• Composting is a biological process applied primarily to suitable organic solids (e.g., primary sludge, biosolids), not to mixed screenings which often contain inerts and plastics.

Concept / Approach:
Identify which statement conflicts with accepted terminology and practice. The key distinction is between incineration (thermal oxidation/burning) and composting (aerobic biological stabilization). Screenings are unsuitable for composting because of their heterogeneity and contamination; if burned, the correct term is incineration.

Step-by-Step Solution:
1) Recognize that materials caught on screens are called screenings. This is standard terminology.2) Typical disposal options for screenings include incineration, burial in sanitary landfills, or controlled dumping where permitted. These are accepted practices.3) Burning screenings is a thermal process. The correct term for burning is incineration.4) Composting refers to controlled aerobic biodegradation of putrescible organics. Mixed screenings are generally not composted.5) Therefore, the statement equating burning with composting is incorrect.

Verification / Alternative check:
Cross-check terminology used for sludge (which can be composted) versus screenings (usually disposed or incinerated). The mismatch confirms the incorrect statement.

Why Other Options Are Wrong:
Option A: Correct definition of screenings.Option B: Correct list of common disposal routes.Option C: Correct term—burning equals incineration.Option E: Accurate context—screenings removal is indeed an initial unit operation.

Common Pitfalls:

• Confusing composting (biological) with incineration (thermal).
• Assuming all solids from a plant can be composted; screenings composition makes them unsuitable.
• Overlooking regulatory requirements for handling screenings safely.

Final Answer:
The process of burning screenings is known as composting.