Pumice is a granular naturally occurring product  that is a suitable alternative solution to peat/heather, wood chips or shells for the treatment of odours emanating from the various industrial processes,, sewage and industrial effluents.  The typical use of pumice for each of the various applications is shown in the table below.

Odour and Offgas  Treatment Applications

Treatment / Odour  Type	Hydrogen Sulphide	Mercaptans	VOCs
Biological Odour Control	Biomass Support	Biomass Support	-
OffGasTreatment			Biomass Support

Applications – Process Descriptions

1. Odour Control in Sewage Treatment Works

The treatment of domestic sewage requires initial screening for the    removal of heavy and large suspended solids followed by primary settlement and some form of biological treatment and a further settlement stage. In larger works subsequent treatment of the main flows include tertiary treatment to further reduce the suspended solids and ammonia concentrations and  a process to enable the sludges to be disposed of in a sustainable and safe manner.

Each of these processes can give rise to harmful odours that generally comprise hydrogen sulphide and mercaptans ( sulphurous organic products) that require treatment to make them acceptable for atmospheric discharge.

Odour treatment processes rely on wet chemical scrubbing, dry scrubbing or biological treatment with the latter becoming the more popular and cost effective solution.

Pumice as supplied by Techfil(Europe)Ltd is rapidly replacing the previously used biomass support systems of peat/heather, wood chips  or mussel shells. Not participating in the biological process, the pumice is not “consumed” in the manner of the alternatives and gives a much longer life ( typically greater than 15 years) yet does not blind and retains its original low presuuer drop and hence low running costs.

Performance is as good as the older alternatives and running/ whole life costs are significantly reduced..

 

Advantages include:

• Low capital and installation costs

• Low pressure drop during the life of the plant

• Allows high bed depths and therefore small surface areas

• Low empty bed contact times

• Good removal performance

• Tolerance to variable and shock loads

• Not seriously affected by extremes of temperature

• Suitable for hydrogen sulphide and mercaptans alike

• Equally suitable for industrial applications and VOC control

 

Physical Characteristics

Grades	TN	TP	TQ	TW
Applications	Biomass Support	Biomass Support	Biomass Support	Biomass support
Typical Properties
Size - mm	10 - 14	15 - 25	20 - 30	30 - 50
Silica Content – SiO2 %	70.9	71.75	71.75	71.75
Bulk Density – kg/cu.m	700	650	650	600
Hardness – Mohs	6	6	6	6

Further Information and Technical Support

For further information and case studies please contact us at: info@techfil.co.uk