"Unmasking Odour Neutralisers" - Industrial Odour Control Course - CASANZ. Presented by Victoria Zavras in Western Australia

3. Exhaust emissions usually contain
significant amounts of various
odorous components.
The perceived odour is due to the
effect of all compounds in the mixture
and depends upon the concentration
and odorous qualities of the
component compounds.

4. Therefore, it is logical that an odorous gas sample
be characterised in two ways.
1. Analytical expression, whereby
the components are identified and
their concentrations are measured
2. Sensory expression, where the
human response to the odorous
mix is measured.

5. GC/MS Analysis
reveals the composition
of the odorous mix but
will not be able to
determine the human
response.

6. Olfactometry reveals the
human response to a
particular odour mix but
cannot address its
chemistry.

8. There are a number of products on the market claiming that
odour emissions can be „neutralised‟ by the addition of certain
components into the air stream
Traditionally, these types of products are split into two
broad categories
Odour Masking
Neutralisers Agents

9. What do the suppliers of these products claim?
“we do not mask, we neutralise!”
“encapsulation & absorption”
“unique blend of essential oils”
“treat all odours with one spray!”
“CHEAP AS CHIPS! ”

10. Based on these vague and grandiose
claims, the facility operator would
mostly out of desperation due to
pressure from regulators and the
community purchase these products.
Is it any wonder, then, that Facility
Operators opt for the ‟QUICK FIX‟
and „cheap as chips‟ solution?

11. Quite a few dollars later, it
doesn‟t take long for the
operator to feel disappointment
and then anger that the “quick
fix” doesn‟t really work.
Herein a vicious cycle begins

12. What are these products
and how do we distinguish
between them?
Do they work, and if not,
why are they used with
such regularity?

14. Essential Oil Blend
Essential Oils, terpene &
emulsifier formulations
the products
Surfactant Induced
Absorption Technology
Various types of surfactants
& blends thereof (Odourless)
Surfactant Induced Absorption
Technology +
Essential Oil Blend
Formulation based on a
combination of the first two
above

15. Surfactant Induced
the products
Absorption Technology
(Site Specific Formulations –
fragranced & odourless)
Various types of surfactants
& blends thereof
Masking Agent
Aromatic oils, perfumes & fragrances
(mainly bubble-gum, musk, citrus and
rose types)

16. Laboratory
investigation
A simulated stack and odorous air generator was set
up at the ANSTO Laboratories at Lucas Heights. Air
samples were subsequently transported to the Centre
for Wastewater Treatment‟s Odour Research
Laboratory at the University of New South Wales.

17. Manifold inserted into „stack‟
– raw odour is then
Permeation Raw Odour challenged with sprayed Sample
Device „Stack‟ Collected products collection

18. Sample
is
collected
Odour generating
device (Permeation)
„Raw Odour‟ is pumped
into the „stack‟

19. Spray system is turned on and the
Sample nozzles spray the odour neutraliser
is
collected
Odour neutraliser is
introduced into the stack
5 mins after the Raw
Odour
Raw odour is introduced
into the stack

20. Synthetic Sewage Odours
78% Removal With Water alone
Olfactometry (ODU)
90% Removal With SIAT
(Odourless)
66% Removal With SIAT
+ Essential Oil Blend

21. Sulphur Dioxide – Initial
85% Reduction with water alone
95% Reduction with SIAT (Odourless)
Dynamic Olfactometry (ODU)
93% Reduction with SIAT &
Essential Oil Blend
87% Reduction with
Masking Agent

22. Sulphur Dioxide – 24 Hrs Later
25% Reduction of SO2 after 24 hrs in Tedlar bag
73% Reduction with Water alone
Dynamic Olfactometry (ODU)
95% Reduction with SIAT
95% Reduction with SIAT
+ Essential Oil Blend
78% Reduction
With Masking
Agent

23. Sulphur Dioxide – Comparison
SO2 Levels increased 25% 24 hrs
after treatment
SO2 Levels remained the same
24 Hrs after treatment
Dynamic Olfactometry (ODU)
SO2 Levels decreased 33%
24 Hrs after treatment
SO2 Levels
Increased
39% 24 Hrs
after
treatment

24. On-Site Investigations –
Sewage Treatment Plant –
Tuncurry, Forster
The misting system remained
off and a section of the inlet
works were covered - Raw
Odour samples were collected
Exposed inlet works – existing
misting system already using a
odour neutralising agent
The misting system was turned
off and Raw Odour samples were
collected

25. On-site: Sewage Treatment Plant
83% reduction with water alone
88% reduction with Essential Oil
Blend
Dynamic Olfactometry (ODU)
83%
Reduction
With SIAT &
Essential
Oil Blend
18%
Reduction
with
Masking
Agent

27. Foundry (Ferrous)
Cooling Line
To nozzles Stack
Cherry picker was used
Control
unit & to reach exit of stack
pump
Sampling point
3 #1.5 nozzles
installed in stack
Solution tank
700 mm stack diameter
Fan
Cooling mould(s) Odour control application device

28. Foundry (Ferrous)
8.5% Reduction with Essential Oil
3.2%
Blend
Reduction
with
Masking
60.6% Reduction Agent
with SIAT &
Essential Oil Blend
99.3%
97.9%
Reduction
Reduction
with Site
with SIAT
Specific SIAT

29. Poultry Shed
1. Windbreak erected around
exhaust fans (Side View)
Row of atomising nozzles
Dust & odour
3. Top View
Exhaust
2. Exhaust fans
Dust & odour Nozzles
2a. Removal
windbreak wall
Sampling point

30. Poultry Shed
62% Reduction with 1.8%
Essential Oil Blend Reduction
with
79% Reduction Masking
with SIAT Agent
73& Reduction
with SIAT +
Essential Oil
Blend
97.8%
Reduction
with Site
Specific
Formula

31. Tyre Manufacturing

32. Tyre Manufacturing
Emissions from Stack
Sampling Port
Treatment
Samples sent to Laboratory

33. Tyre Manufacturing
22% Reduction with Essential Oil Blends
62% Reduction with SIAT
65%
Reduction
with SIAT & 2%
Essential Oil Reduction
Blend with
81% Masking
Reduction Agent
with SS.
SIAT

34. Rubber Products Manufacturing
Raw Odour Sampling Raw Odour Challenged with
Odour Neutralisers

35. Rubber Products Manufacturing

X
X

37. Application Equipment
Compressed Air System

38. Application Equipment
High Pressure System >1000 psi

39. Application Equipment
Low Pressure System 250 psi

40. Choice of application equipment and nozzle is integral
to the performance of the odour neutralising agent
Application of odour neutralisers should be limited to
atomisation. Odour Neutralising agents fail to
perform in the liquid phase, and in most instances will
not work in scrubbers.

42. Outcome:
Masking Agents are not suitable for use in industrial odour
control applications at any time.
Masking Agents have little or no effect on complex odour
mixtures. Olfactometry revealed that masking agents to do
not have an “additive” effect on the malodour being
challenged.
Masking Agents are ideal for low level, simple and
transient odours – such as in a hotel lobby or lavatory
Masking Agents consistently
failed to perform in “real-life”.

43. Outcome:
Essential Oil Blends have succeeded in some instances but
their effects are highly inconsistent
“Essential Oil Blends” may assist in the reduction of
odours in some instances.
Essential Oil Blends so not show any consistency in
removal efficiency and their application can best be
described as “luck of the draw”
Some Essential Oil Blends have resulted in a significant
reduction on sewage odours – provided the odours are from
domestic sewage

44. The bulk of “odour neutralisers” assessed over the
years have a high concentration of essential oils.
The SIAT products have some low concentration
oils which contain functional groups and surface
active agents

45. Some companies professing to be
“odour control specialists” and
''environmentally friendly'' are using
essential oils as a “technology” to treat
malodours. Our research has revealed
that the use of essential oils is not very
environmentally friendly when you
consider that trees need to be chopped
down, squeezing out the oil and using
this oil to reduce odours at an industrial
site.

46. Although the results showed some reduction and
some success when using Essential Oil Blends, it may
finally be about time to move away from these types of
products. For example, if we look at rosemary oil, the
chemical make up includes components such as
geraniol, citronella and pine. Different batches of oils
from different parts of the world have these components
at different concentrations. There is no consistency in
the raw product being used by formulators.

47. The research suggests that a cleaner more
scientific approach is via the use of aroma and
nature identical chemistries and surfactant
based technology.
The components in the mix seem to be reliable
and there was no evidence to suggest that
application of such products „mask‟ the
malodour.
This is very heartening and requires further
study.

48. 17 years of research into these
products have revealed the
following:
The difference between odour neutralising
agents and masking agents lies in the FACT
that some Odour Neutralising Agents do work –
albeit inconsistently depending on the odour
source
Masking Agents are NOT Odour Neutralising
Agents and can best be described as „creative
perfumes‟.

49. 17 years of research into these
products have revealed the
following:
Odour Neutralising Agents can safely be considered in
any odour control application – BUT should be the last on
the operator‟s list
Odour Neutralising Agents are not suitable as a stand
alone treatment for industrial odour control applications.
There is no such thing as “broad-spectrum” or a “cure-
all” odour neutralising agent.

50. The only “cure-all” odour
control product