Environmental, Safety and Sustainability Issues
Environmental, Safety and Sustainability Issues examines the impacts and controls of textile processing. The exam tests wastewater load, emissions, energy, chemical safety, machine guarding, PPE and circularity claims.
Core concepts
- Wastewater load = flow × concentration; COD and BOD measure organic load, not toxicity alone.
- Colour, salts and recalcitrant dyes need segregation and treatment; dilution is not treatment.
- Energy efficiency uses heat recovery, correct motor sizing and process optimization.
- Safety hierarchy: eliminate or substitute, use engineering controls, then administrative controls, with PPE last.
- Sustainability tools include life-cycle assessment, chemical inventory, water footprint and recycled-content traceability.
Worked example
A dyehouse discharges 1,000 m3/day with COD 800 mg/L. Load = 1,000 m3 × 800 g/m3 = 800,000 g/day = 800 kg COD/day. If flow is reduced to 700 m3/day at the same concentration, load falls to 560 kg/day. If concentration rises after segregation, load may not fall; always calculate mass load, not concentration alone.
Traps
- Reporting concentration as load.
- Assuming dilution meets discharge limits.
- Relying on PPE before engineering controls.
- Claiming recycled content without chain-of-custody evidence.