Trade Effluent by asafwewe


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									Trade Effluent

             David Bailey
      Business Services Manager
Trade Effluent Legislation
• Mainly Water Industry Act 1991, and sewerage
  undertaker responsible for enforcement

• Special Category Effluents have to be referred to
  Environment Agency

• IPPC Permits issued by EA can also restrict wastewater
Definition of Trade Effluent
• Any liquid, either with or without particles of matter in
  suspension which is wholly or partly produced in the
  course of a trade or industry carried on at trade

• Water Act 2003 – Secretary of State has additional
  powers to deem liquids to be / not be trade effluent
Trade Effluents
•   Industrial processes - yes
•   Commercial laundry / launderette - yes
•   Commercial swimming pool - yes
•   Food manufacturing sites - yes
•   Hotels, pubs, restaurants, canteens, take aways - no
•   Landfill leachates - no
•   Site drainage - maybe
Permission to discharge
• Trade Effluent discharge can only be legally made with
  Consent of sewerage undertaker
• Application is made by serving a Trade Effluent Notice
• Permission can be unconditional or refused but this is
• Normally discharges Consented with appropriate quality
  / quantity conditions
• Criminal Offence to breach Consent conditions
Trade Effluent Consent Conditions
•   Nature, composition & temperature of effluent
•   Maximum daily volume and flow rate
•   Time of day and receiving sewer
•   Elimination or diminution of specified constituents
•   Provision of monitoring & testing equipment
•   Keeping of records
•   Additional powers to specify treatment - Water Act 2003
Varying Consent conditions
• At any time by mutual agreement with customer

• Unilaterally by SU after two years by issuing a Direction

• Earlier variation by SU within two years is possible but
  may result in claim for compensation if circumstances
  could reasonably have been foreseen
Simple and Pragmatic legislation
• Customer has right of appeal to Ofwat if Consent has
  been refused
• Or if Consent conditions considered to be unreasonable
• Or if variation by Direction is unreasonable
• Promotes cooperative approach
• Ensure sound technical basis for limits or changes
Severn Trent’s approach
  • 3000 Trade Effluents treated at 250 sewage works
  • Major element of our business but as elsewhere long-
    term decline in quantities discharged
     – Reduced importance of manufacturing in UK
       (especially engineering and textiles)
     – Tighter environmental standards
     – Modern production processes
     – Improved environmental management
Consent Conditions set to prevent
•   Hydraulic overload and overflow
•   Sewer damage (blockage and corrosion)
•   Fires and explosions
•   Nuisance or danger to health
•   Toxic effects at receiving sewage works
•   Overloading of sewage works
•   Unacceptable environmental residues
Monitoring Trade Effluent Quality
• Mixture of Standard limits and individual calculations
• Results in limits which are very site specific
• 15000 samples and inspections per year for control and
  charging purposes
• Agree fixed strength where this is appropriate
• Frequency and type of sampling used reflects the risk
  and scale of discharge
• Sewer surveillance in problem areas
Measuring Trade Effluent Volume
• Agreed volumes where appropriate
• Effluent Volumes typically calculated from water supply
  meter readings, or internal water meters on supply to
  effluent producing process
• Larger discharges - positive effluent flow measurement
  using V notch, flume, magflow or venturi meter
• Very site specific with high reliance on customer
  equipment and data
Enforcement Action
• 50 formal samples per year
   – Unresolved problems with consent compliance
   – Following serious incidents
   – Where bad practise may be occurring
• 10 prosecutions / formal cautions per year
• Note – can be trade effluent discharges to foul sewer or
  other problems with Surface Water Sewers
TE Charges – Mogden Formula
•   R up to 49,999 m3 = 19.01 p/m3
•   R ,50,000 to 249.999 m3 = 16.94 p/m3
•   R 250,000 and over = 13.6 p/m3
•   V = 17.23 p/m3
•   B = 29.34 p/Kg COD
•   S = 22.38 p/Kg Suspended Solids
Other Charges
• Additional charge where equipment has been installed
  to remove a residual
• Strong ammonia wastes
• Charges for colour removal from textile effluents
• Charges to cover the cost of providing new or extra
  capacity where appropriate
Effluent Treatment
• Non-ferrous metal removal by neutralisation and
• Simple physical treatment for oil & grease or suspended
  solids removal
• Colour removal by coagulation
• Use of biological or other pre-treatment methods (e.g.
  DAF) is rare
• Typically installed to resolve capacity restrictions rather
  than to reduce discharge costs
Keeping costs under control
• Monitor your water consumption
• Check rinse efficiencies and carry-over rates
• Monitor product and raw material wastage
• Investigate separation of strong wastes for off-site
• Consider pre-treatment to reduce COD and Suspended
• Look at options for re-using effluent or wastes

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