Industrial wastewater sources: Effluents discharged from electroplating shops, blast furnaces, and coal mining operations are primarily characterized by which type of contaminants?

Introduction / Context:
Correctly identifying dominant contaminant classes in industrial wastewater guides selection of treatment processes. Some sources discharge mainly organics (e.g., food processing), while others release metals, acids, alkalis, and suspended minerals typical of inorganic pollution.

Given Data / Assumptions:

• Electroplating effluents often contain heavy metals (Cr, Ni, Cu, Zn) and cyanides/acids.
• Blast furnace water can carry suspended inorganics, scale, oil traces, and dissolved inorganic species from gas cleaning.
• Coal mining drainage frequently includes suspended solids and acid mine drainage with sulphates, iron, and other inorganic ions.

Concept / Approach:
These sectors are dominated by inorganic contaminants: metals, mineral acids/alkalis, and mineral particulates. While oils or organics may be present in trace amounts (e.g., lubricants), the defining treatment challenge is precipitation/neutralization for metals and pH, plus solids removal. Radioactivity is not characteristic for these sources under normal conditions.

Step-by-Step Solution:
Match each industry to pollutant profile: electroplating → metals; blast furnace → inorganics/solids; mining → acid mine drainage.Identify the common class: predominantly inorganic.Select “inorganic.”

Verification / Alternative check:
Treatment trains typically include pH adjustment, chemical precipitation, coagulation–flocculation, and sedimentation/filtration, all aimed at inorganic removal, confirming the dominant class.

Why Other Options Are Wrong:
Organic: Not the dominant load; biodegradation is secondary here.Radioactive: Not typical of these industries.None of these: Incorrect because “inorganic” is clearly applicable.

Common Pitfalls:

• Overgeneralizing from industries with high organic load to metallurgical sectors.
• Neglecting the need for stringent metals compliance before discharge.

Final Answer:
inorganic