Wastewater treatment solutions

Presentation to Perilex Ltd

28th April 2010

Definition of the project

Treatment of effluent from Perilex production facility to enable discharge to the environment.

Main requirements:

Compliance with Environment Agency provisional consent BOD 10mg/L COD 125mg/L (UWWTD Requirement) Suspended Solids 20mg/L Ammonia 5mg/L

Feasible in terms of initial capital and ongoing operational costs

Effluent to be treatedDischarge volume from Perilex facility is 1500m3/day

Parameter Concentration

(mg/L)

COD 8500

BOD 3400

Ammonia 1

Suspended Solids

250

FOG 3000

Parameter Load

(kg/day)

COD 12750

BOD 5100

Ammonia 1.5

Suspended Solids

375

FOG 4500

• High COD Load

• High Fat Load

• Low Ammonia load

• Query nutrient availability

• Query treatability

Treatment options

Preliminary treatment only followed by discharge to sewer

Anaerobic Treatment Aerobic Treatment

Discharge to Sewer

Treat to a preliminary standard under UWWTD requirements and then discharge to sewer

Discharge cost without treatment £9000/day

Discharge cost with primary secondary stage £1200/day

25 year amortised cost of a two stage process £725/day

Anaerobic Treatment

Advantages Produces Biogas Minimises sludge

production

UASB System is High rate system Low Footprint

Anaerobic Treatment

UASB Secondary Aeration Stage

Final Settlement

Biogas

Anaerobic Treatment

Advantages Produces Biogas Minimises sludge

production

UASB System is High rate system Low Footprint

Disadvantages Treatment at elevated

temperatures Requires secondary

treatment stage Without CHP Biogas can’t

be utilised fully Unable to treat FOG and

not compatible with a DAF stage that treats FOG

Aerobic Treatment

Advantages Can cope with FOG

with a primary DAF stage

Complete solution although 2 stage

Capable of very good effluent quality

Easy to operate and control

Adaptable

Disadvantages Energy intensive Large sludge

production

Treatment solution

Primary treatment using Dissolved Air Flotation for FOG and COD Removal

Two stage activated sludge biological treatment Treatment of waste sludges using anaerobic

digestion Dewatering onsite and disposal of waste

sludges, potential to produce an enhanced treated product

Treatment solution

Discharge

Sludge for disposal

RAS LineRAS Line

DAF Unit High Rate ASPVolume 766m3

Diameter 14mDepth 5mAir 1960m3/h

Intermediate Settlement tankVolume 260m3

Diameter 11.5mSidewall Depth 2.5m

Final Settlement tankVolume 260m3

Diameter 11.5mSidewall Depth 2.5m

Low Rate ASPVolume 766m3

Diameter 14mDepth 5mAir 460m3/h

Sludge DigestionVolume 1020m3

Diameter 16mHeight 2.5m

Biogas productionVolume 1212m3/dNet Energy +18kW

DAF Compressor

Sludge consolidation tankVolume 170m3

Sludge Centrifuge

Treatment SolutionGeneral Arrangement

1

2

3

4

56

P-2

7

8

9

10

Key1 Inlet PS2 DAF Unit3 1ry ASP4 2ndry ASP5 Consolidation tank6 Digester7 Sludge Dewatering/Boiler House8 Blower House9 Flare Stack10 Outfall

Scale: 1:400

Operational Expenditure

Estimate weekly cost for Power £700 Sludge treatment £420 Sludge disposal £300 Maintenance costs £280 Staff costs £560

Annual Cost £117,500

Further work

Further work to examine the effluent nature Biodegradability Nutrient availability

Agree and finalise the treatment option Finalise operational and capital expenditure Examination of the costs benefits Potential to look into sewer disposal Examination at the NPC Examination of the sludge disposal strategy

Any Questions ??