Question

The primary treatment methods in meat industry effluent treatments reduce ______.

• A. Fat upto 70%, susepended solids upto 25% and BOD upto 10%
• B. Fat upto 50%, susepended solids upto 95% and BOD upto 65%
• C. Fat upto 90%, susepended solids upto 65% and BOD upto 35%
• D. Fat upto 80%, susepended solids upto 45% and BOD upto 55%

Hint:

Primary treatment is physical separation. Since fats readily float, they are highly removed (90%), while dissolved organic molecules causing high BOD require biological secondary treatment.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Effluent treatment in food processing industries is divided into primary (physical/mechanical), secondary (biological), and tertiary (chemical/polishing) treatment steps.

Step 2: Detailed Explanation:
Meat industry wastewater contains extremely high loads of biodegradable organic matter, suspended solids (SS), and fats, oils, and grease (FOG).
Primary treatment typically utilizes physical screens, grease traps, grit chambers, and Dissolved Air Flotation (DAF) units.
- Because fats and grease float easily, these mechanical separation methods are highly efficient, removing up to 90% of fat.
- Gravity settling and screening remove a significant portion of insoluble organic particulate matter, reducing suspended solids by up to 65%.
- By removing these solids and fats, the organic load is partially reduced, lowering the BOD by up to 35% before the effluent enters biological treatment.

Step 3: Final Answer:
Primary treatment in the meat industry reduces fats by up to 90%, suspended solids by up to 65%, and BOD by up to 35%.