Proceedings

UK Lessons learned

Sizing in the UK is different

• 95%ile compliance spot samples
• Large transition from dry to wet weather conditions / underloading on Bio-P
• Larger Influent Buffers for smaller sites (Originally 30% of reactor – now typically same size) N-1 – not required in Europe – (N-1+??)
  Instrumentation
• Initial designs – heavy on instruments – gave wrong impression & added cost/complexity
• Current designs streamlined
  Sludge Return Liquors
• Balancing liquors can optimise design
  Chemical requirements – can operate chemical free but now recommend it as seat belt and for future-proofing. Tertiary Treatment – Often not needed. Final effluent typically comparable to long sludge age ASP when designing UV