CLIENT: 
Affinity Water
  • €2M Design & Build Contract
  • Plant Capacity: 11.5 Ml/day
  • Constructed and commissioned within 6 months
  • Levels of iron reduced from 1.2 mg/l to less than 0.02 mg/l
CHALLENGE: 

The Contract required the design and construction of a media filtration plant to specifically remove Iron and Manganese from the raw water extracted from 3 boreholes.

The old plant comprised biological filters which were not able to remove the iron and manganese down to acceptable limits. Primarily the manganese was of sufficient presence in the treated water that it was precipitating out in the networks, coating the mains and causing general maintenance problems.

ANSWER: 

The incoming levels of manganese average 0.045mg/l and the new plant removes it down to less than 0.02 mg/l. Similarly with the iron, the new plant removes the levels from 1.2 mg/l down to less than 0.02 mg/l, Final turbidity is also reduced down to less than 0.2 NTU. The new filtration plant ties into existing plant and re-uses modified existing plant under this contract to achieve these standards. Sophisticated controls were also installed to ensure fully automatic running of the new and existing plant. Daily plant throughput is 11.5MLD. The Plant was constructed and commissioned within 6 months.

PROCESS SUMMARY: 
  • Cascade Aeration
  • Sand Filtration
  • Backwash Pumps,  Pipework & Valves
  • Filter Control System
  • Supernatant Pumping
  • Washwater Pumping & Lamellae clarification
  • Chemical Storage & Dosing
  • Instrumentation & Controls
  • Flow Sampling & Monitoring
  • SCADA
STANDARDS: 
  • Average raw water ≤ 0.2 NTU with a maximum turbidity of 1 NTU.
  • Filter water quality not to exceed 0.2 NTU on a 95% ile basis.
  • Filter water quality not to exceed 20 μg/l Fe on a 95% ile basis.
  • Filter water quality not to exceed 5 μg/l Mn on a 95% ile basis

© Response Group 2013

Main Office: Response Group, Railway Road, Charleville, County Cork, Ireland