ASK Piearcey

Odour Control Systems – One of UK’s Largest Sewage OCUs

A.S.K. Piearcey Ltd were engaged by their exclusive waste-water treatment partners Plasticon UK, to carry out the process design and flow balancing of  a flag ship odour control plant situated on the South Coast.

The system handles up to 250,000 m3/hr of odorous air from the main plant and there 2 further satellite systems handling approximately 3000 m3/hr each.

ASKP Ltd provided the process design based on a concept from the main process consultant. The system comprised venturi scrubbing for dryer off-gas solids removal and acid scrubbing for ammonia removal. This was followed by caustic-hypochlorite scrubbing and final carbon adsorber polishing.

Venturi Separator Sump

Venturi Separator Sump


The venturi system handled up to 19100 m3/hr of dryer off-gas but had 2 modes of operation with automatically varied flow control set point and alarm level adjustment. The venturi throat could be varied by means of an adjustable throat plunger and worked on a constant overflow of final effluent from the separator vessel (above).

Acid Scrubber

Acid Scrubber

The Acid scrubbers handle around 47,000 m3/hr of the high odour (from direct coupled extracts) and are there primarily to remove ammonia and some of the amine present.

Hypo-Caustic Scrubbers

Hypo-Caustic Scrubbers

The Hypo-Caustic Scrubbers handle the entire air flow at 250,000 m3/hr and can temporarily handle this with just 2 of the 3 duty scrubbers in operation


Carbon loading unit

Carbon loading unit

The 3 carbon units held around 125 tonnes of copper oxide impregnated carbon to fine tune the odour control performance of the system. Each had to be loaded with a specially built carbon loading system (above).

The air was conveyed from the various field extract points via a vast network of ducting.

Field Process  Odour Extract

Field Process Odour Extract

3m diameter Combined Exhaust to Stack

3m diameter Combined Exhaust to Stack


The ducting was fabricated up to 3m internal diameter to meet the agreed velocity consents.

Carbon adsorber units, also containing copper oxide impregnated carbon were used for odour control in satellite pumping stations.

The system below shows a system with duty standby extract fans and local control panel.

Odour Control Unit at Satellite Pumping Station

Odour Control Unit at Satellite Pumping Station

The Entire project value was circa £6.5 million. ASKP also assisted with HAZOP, HAZChem and commissioning. We provided Detailed Design, Operational instructions, Control Philosophy, commissioning schedule and training for the entire odour control system.

Fan Pressure Testing by ASKP Ltd

Fan Pressure Testing by ASKP Ltd











Rendering Odour Control

A.S.K. Piearcey Ltd were engaged by PDM (John Knights) to look at a means of improving the existing odour control at their Silvertown Facility in London.

The project was carried out in 2 stages:

Stage 1 a site visit to inspect the current system and gather the relevant design information. Which included a proposed additional test regime carried out by PDM.

Stage 2 a conceptual process design to provide a system capable of handling around 8000 m3/hr of concentrated odours which worked with the existing boiler incineration route to provide constant, seamless and reliable odour control.

The design is currently being procured for another PDM site in Nuneaton, for a larger air flow.

Our design was adapted and constructed in a very short period of time to provide an odour control safeguard in time for the London Olympics. The system was a great success, dramatically reducing the number of odour complaints, even with the additional footfall during the summer months. The design is an acid scrubber followed by a carbon adsorber (with specially impregnated, activated carbon).

The original design also included a venturi pre-scrubber for fat removal but this was not deemed necessary for the adapted design.


The design is currently being procured for another PDM site in Nuneaton, for a larger air flow.

Sewage Odour Control Pilot Trials in Spain

A.S.K. Piearcey (ASKPL) have assisted Cover manufacturing specialists JSF Hidraulica (JSF) of Madrid in developing their odour control portfolio in Spain.

After some preliminary design work by ASKPL, JSF have built and tested a pilot system (below) consisting of a bio-filter and a Carbon polisher.

JSF have tried a number of different media in the vessels to find an optimum for sewage odour control.


JSF are leaders in the aluminium structures, solid tank covers (below) and floating
tank covers market place. Odour control was a natural progression from their
various tank covering projects and they had received a number of enquiries to
provide odour abatement with their covers. They decided that a pilot trial was
an effective and economic means of developing track
record and confidence in the approach suggested by ourselves.


After extensive pilot trials involving various media they have developed a system
(with design assistance from ASKPL), which
can be used to handle the majority of the sewage odour control applications that
they come across. The bio-filter was entirely constructed from
aluminium and lined with a chemical resistant liner.


Measurements of air flow, H2S  inlet and outlet as well as temperature and irrigation were made and data-logged where practical.

The pilot trial, in Fuengirola  (south coast of Spain) was so successful that the plant manager is seeking to replace the existing scrubbers with the bio-filter approach.

JSF have since secured 2 large orders involving bio-filters and carbon adsorbers with design assistance from ASKPL.

H2S detector 1

Industrial VOC Abatement
May 26, 2011, 12:40 pm
Filed under: Case Studies | Tags: , , , ,

Industrial VOC Abatement

ASK Piearcey designed a range of split bed rect-annular carbon adsorbers for the adsorption of methyl chloride on a coating process.

The equipment was manufactured to our designs by EIS Ltd

ASK Piearcey were asked to investigate the possible release of VOCs from a printing process. Smoke testing and flow measurement from ASK Piearcey demonstrated clearly that there were no fugitive emissions from the process. By investigating the prime VOC sources in the process ASKP Ltd were able to advise the client regarding minor extract philosophy changes to improve stack emissions, which were found to be compliant

VOC Abatement

VOC Abatement

ASK Piearcey were asked to provide designs for movable carbon adsorbers to assist in the removal of VOCS from combined vent and breather sources, some of which ere already treated via a scrubber. Modifications to the scrubber operation involving re-use of another waste water stream improved the scrubber performance and hence allowed for an improvement in design carbon bed life. The units are due to replace existing static adsorbers and will provide for easier carbon change and reduction in on site, associated hazards.

The project was under taken with Transvac Ltd who built the original scrubber.

Industrial Odour Control
May 26, 2011, 12:35 pm
Filed under: Case Studies | Tags: , , , , ,

Industrial Odour Control

ASK Piearcey  designed the adsorbers for the removal of odour generated by the baking of pet food treats.

The adsorbers were then fabricated by the customer with ASK Piearcey Ltd assisting with the sourcing of the carbon. ASK Piearcey  also assisted the customer with the choice of pre-filter to remove the oil aerosol present in the off-gas.



ASK Piearcey were asked to investigate the odorous releases from a high temperature autoclave sterilisation process. Tests were conducted for hydrogen sulphide and ammonia and then a full scale abatement system was designed to handle the fume and other extracts.

For more information on industrial odour control please call us on 01909 518 837 or 07877 456 718 and ask for Andrew.

Sewage Odour Control

Sewage Odour Control

ASK Piearcey designed and commissioned this odour control system consisting of a pumice stone biofilter and copper oxide impregnated carbon unit.

The manufacture and installation is by Odour Services Ltd. The system treats around 70ppm of Hydrogen sulphide with 150ppm peaks lasting several hours.

For further information on Sewage odour call Andrew  on 01909 518 837.

Sewage Odour Control

ASK Piearcey field testing for gas flow and H2S

ASK Piearcey Ltd were asked to provide commissioning schedules and carry out the commissioning/flow balancing of this odour control system in the North West of England. The system extracts from various sources around site and uses a caustic/hypochlorite scrubber followed by carbon adsorption (with humidity control) to handle the odorous emissions. The system was a turnkey project manufactured and installed by Plasticon U.K Ltd.