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Abridged Project Methodology

15th October 2013

Graham Mann

Current Situation

An assessment or audit of the waste water being generated is the most important starting point for any project.

This is split into two categories:

1.Discharge consents to ensure compliance is being achieved – typically flow, pH, oils and grease, solids, COD, phosphate, ammonia, heavy metals etc

2.Data regarding chargeable components – flow, solids and COD only for the MOGDEN formula

Typical charts can be seen on the next pages

Effluent Treatment

1. Physical

Filtration:

Traditional wedge wire screensminimum solid capture = 1 mm

Revolutionary Ogden Water FilSysminimum solid capture = 50 microns

Settlement:

Heavier material sinks to the bottom

Flotation:

Less dense material floats to the surface

Effluent Treatment

Ogden Water Ltd.

2. Chemical

An enhancement of physical separation.

Chemicals can be used to:

Increase the chances of capture by binding particles together

Increase the density of the particles through chemical binding

Use of chemical treatment to encourage binding of solids toair (micro bubbles) for enhanced flotation

(Dissolved Air Flotation)

Effluent Treatment

3. Biological

Simple forms of bacteria are used to eat the organic material present in the wastewater.

Through their metabolism, the organic material is transformed into cellular mass, which is no longer in solution but can be precipitated at the bottom of a settling tank.

The water exiting the system is therefore much cleaner.

Effluent Treatment

Reasons to treat:

Compliance

Cost saving

Water re-use

 

Example Effluent Treatment Projects

Physical – Filtration System plant:

1,200 m3/day of effluentCOD 1,500 mg/l Solids 2,000 mg/l. 

Budget £120,000. 

Chemical – Dissolved Air Flotation plant:

480 m3/day of effluentCOD 4,500 mg/l Solids 1,000 mg/l. 

Budget £80,000. 

 

Effluent Treatment

Biological – MBR plant with RO for water recovery:

400 m3/day of effluentCOD 2,500 mg/l Ammonia 200 mg/l. 

Budget £1m. 

Recovered water = 300m3/day

 If greater than 40% is recycled, there is access to grant funding and the possibility of enhanced Capital Allowance to be claimed.

 

Project Methodology and Work Schedule

24 hourly sampling and analysis programme

Laboratory test work – solids removal and effect on COD, pH correction

Budget quotation – funding available, timescales involved etc.

Full draft quotation

Visit to reference sites

Presentation, discussion meetings to finalise the quote

Design, build, install

Service, support and continuous improvement