vti rest of the ANOUNCEMENT

VIROTEC INTERNATIONAL LIMITED 2002-09-23 ASX-SIGNAL-G

HOMEX - Brisbane

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VIROSEWAGE(TM) TECHNOLOGY

The following information provides greater detail on the various
aspects of ViroSewage(TM) technology and provides examples of some of
the associated markets.


1) ODOUR ELIMINATION - EXISTING SEWAGE PLANTS

Older sewage treatment works are now much closer to urban centres
than when they were first built. Expanding cities and towns mean that
houses are located close to the original treatment works. Complaints
frequently refer to the unpleasant odour emanating from the open
basins where the wastewater is treated and to the odour released from
biosolids (treated sludge) stored at composting sites or sent to
landfill. In some crowded cities, governments have been forced to
replace all the conventional open tanks in sewage treatment works
with covered units to control the emission of foul air.

ViroSewage(TM) technology can be applied upstream of known odour
sources within a treatment facility, resulting in a reduction in the
biological production of organic and inorganic volatile sulphur
compounds that cause odour problems, virtually eliminating the
discharge of odour from these points to the atmosphere.

ViroSewage(TM) technology is a breakthrough in an industry that has
employed various unsuccessful means to control odour pollution,
including the addition to sewage of water, oxygen, lime, hydrogen
peroxide, biological additives, and the use of air phase odour
controls such as activated carbon adsorbers, biofilters and odour
neutralising agents.


2) ODOUR ELIMINATION - NEW SEWAGE PLANTS

In China all cities are required to establish wastewater treatment
facilities that process 45 per cent of sewage by 2005 and 60 per cent
by 2010. Since 1998, the Chinese government has invested 200 billion
yuan (24 billion U.S. dollars) annually in urban construction. The
United Nations Industrial Development Organization has promised to
allocate 30 billion U.S. dollars to help sewage treatment in major
Chinese cities in the next decade.

A facility employing ViroSewage(TM) technology should have no odour
pollution concerns.

As several major companies are currently competing to establish
treatment facilities in China, the Directors believe Virotec's
technology can significantly influence proximity considerations of
any proposed development and this could lead to a significant
reduction in capital outlay. Throughout the world, planning
authorities refuse planning permission on the grounds that the odour
nuisance from the proposed development will be detrimental to the
amenity of the area and subsequently, sewage treatment facilities are
required to be located a significant distance from urban centres.


3) INCREASED CAPACITY

In the US, a nationwide analysis revealed that between 1968 and 1996
the EPA provided $61.1 billion in Federal Construction Grants Program
funds to help fund new or upgrade existing publicly owned treatment
facilities to cope with increasing demand. The States, local
authorities and private sector made an even greater investment of
well over $200 billion. The survey also revealed the overall number
of people served by publicly owned treatment facilities increased
from 140.1 million in 1968 to 189.7 million in 1996 (a 35% increase)
and the number of people served by publicly owned treatment
facilities with secondary or greater levels of wastewater treatment
almost doubled from 85.9 million in 1968 to 164.8 million in 1996.

Throughout the world, local governments are being asked to play a
larger role in water resources financing to cope with rapidly
increasing hydraulic and organic loads on sewage treatment
facilities. For instance, in Australia, approximately 70% of the
population live in large metropolitan centres with the consequence
that large volumes of sludge are produced in a few centralised
locations.

ViroSewage(TM) technology stimulates faster particle-fluid separation
resulting in up to a 50% reduction in residence time in the final
clarifier. This has significant repercussions for treatment plants
operating at 100% capacity and facing costly upgrades. Potentially,
the ViroSewage(TM) process allows existing plants to significantly
increase current capacity without substantial increase in capital
expenditure.

Furthermore, ViroSewage(TM) technology almost eliminates the need for
costly flocculants.


4) PHOSPHATE MANAGEMENT

The total volume of treated water in North America is about 20
gallons per person per day, or 100 trillion gallons per year. It is
accepted worldwide that phosphorus needs to be removed from sewage
effluent before discharge, to prevent enhanced eutrophication
(especially blue green algae) particularly in shallow fresh water
bodies. However, quite often, the liquid effluent discharge pipes
from many municipal sewage treatment plants are "point sources" of
immense quantities of nutrients (nitrate and phosphate). EPA
regulatory authorities worldwide continually seek reductions in the
discharge of phosphorous nutrients from treated sewage effluent.

A further phase of the ViroSewage(TM) treatment reduces the soluble
inorganic phosphorous content in sewage effluent to the minimum
theoretical solubility limit for phosphate precipitates. In turn, up
to 85% of the phosphate nutrient is transferred to the VST enriched
biosolids in a remarkably stable form, where it remains stable even
in anoxic conditions. Unlike normal biosolids, phosphate enriched VST
biosolids can potentially be used to improve soils whose pH is even
less than 5.5

ViroSewage(TM) technology, when tested at a conventional sewage
treatment plant, improved the traditional poor rate of phosphorous
removal from the effluent stream from approximately 10% - 30% to over
99%.

In a Biological Nutrient Removal sewage treatment plant, phosphate
removal is highly dependent on both the incoming phosphate loading
and the current plant operating conditions. Disruption to the BNR
process may result from large variation in hydraulic flow, material
overload, chemical or toxic shock, all of which generally result in
excessive phosphate discharge.

ViroSewage(TM) technology at a BNR plant, not only ensures the
removal of over 99% of phosphorous from the effluent stream, it
allows the BNR process to concentrate exclusively on the removal of
nitrogen, considerably improving the efficiency of the BNR process
and effectively reducing manpower hours needed for critical ongoing
BNR management.


5) HEAVY METAL IMMOBILISATION

The EU estimates 67% of European biosolids in the short term, and 83%
in the long term, fail to comply with limit values on heavy metals or
organic compounds in sludge or in soil. Without the ability to comply
with the stricter restrictions that are currently being imposed, it
has been estimated that local authorities may have to bear a cost of
up to 60% for the cost of switching from land-spreading to
incineration of biosolids.

In the USA, the EPA has recently proposed strict guidelines for the
disposal of biosolids in landfills, depending on the proximity of the
landfill to pristine groundwater which is an irreplaceable source of
drinking water. Leachate problems can arise from zinc, copper, lead
and even cadmium found in biosolids produced in large cities.

ViroSewage(TM) technology can be used to immobilize heavy metals in
biosolids so that stringent standards for leachability of heavy
metals are met.


6) RECYCLED BIOSOLIDS

Local governments make the decision whether to incinerate biosolids,
bury them in a landfill, dump them in oceans or recycle them as a
fertilizer. In Sydney, Australia, for example, large volumes of
sludge will continue to be produced in the coastal suburbs while the
nearest suitable land-fill sites could be as much as 100km away. In
fact, just over half the world's population - around 3.2 billion
people - occupy a coastal strip 200 kilometres wide (120 miles),
representing only 10 per cent of the earth's land surface. When
biosolids are successfully recycled, they can be applied as
fertilizer to sustainably improve and maintain productive soils and
stimulate plant growth.

In the USA, only biosolids that meet the most stringent standards
spelled out in the U.S. Environmental Protection Agency Federal and
state rules can be approved for use as a fertilizer. Since 1992, when
a ban on ocean dumping was instituted, applying biosolids to land has
reduced the amount of sewage sludge that would otherwise need to be
buried in landfills or incinerated. About 60 percent of sewage sludge
produced is converted for land application. In 1998 the quantity of
sludge generated in the US was estimated to be approximately 7.5
million dry tons per year.

In Europe, the total amount of sludge produced in the fifteen EU
Member States is predicted to increase from 6.6 million tonnes of dry
matter in 1992 to at least 9.4 million tonnes in 2005. Most experts,
particularly from the European Union, consider some form of
land-spreading as the most sustainable way. The EU expects the
proportion of sludge used for agriculture and soil conditioning to
have increased by 73% by 2005, to 53 % of the total produced.

In response to environmental concerns, more and more local
governments are selecting alternatives for their biosolids that will
do the most for organics recycling and beneficial reuse. Many local
governments are choosing composting to produce a value-added product
that is saleable in multiple markets. Composting is primarily the
acceleration of natural biodegradation.

The elevated temperatures of the controlled aeration, which is
produced by the microbial action, significantly reduces pathogens and
breaks down the composting mass until a stabilized product is
produced.

Traditionally, the natural biological action creates a temperature
rise ranging from 55C to 65C and the reaction temperature in the pile
must be at least 55deg.C for three weeks to achieve efficient
pasteurization. ViroSewage(TM) technology results in the temperature
rising as high as 85deg.C while reducing the possibility of
spontaneous combustion and eliminating 100% of pathogens, generally
within 24 hours of reaching this temperature.

ViroSewage(TM) technology also results in a 65% reduction in time
required for the composting stabilization process enabling faster
turnover and significantly reducing the size of the composting
facility.

Biosolids composting also requires the addition of a bulking agent to
provide air space and to make the mixture permeable. Typical bulking
agents include green mulch, wood chips, shredded bark, sawdust,
shredded paper other materials. ViroSewage(TM) technology results in
a 40% reduction in the required volume of the bulking agent and,
again this contributes to a large reduction in the size of the
composting facility.

ViroSewage(TM) technology not only contributes to faster composting,
it also vastly improves the quality of the end products for market
which range from a superior composted product, a first class soil
conditioner and even a retail potting mix.

Traditionally, all facilities handling biosolids produce odours and
frequently composting facilities are forced to operate at reduced
capacity due to objectionable odour issues. In the US several of the
large composting facilities have designed and engineered expensive
air scrubbers to reduce emissions. ViroSewage(TM) technology
eliminates offensive odour pollution.

Composting facilities also require drainage systems and a "pond" to
catch runoff to eliminate chances of non-point source pollution from
noxious leachate. ViroSewage(TM) technology significantly reduces
leachate run off.

It is becoming increasingly obvious that composted biosolids have
enormous reuse potential. In the US, products from composted
biosolids are used on some of the most high-profile lawns and gardens
in the country; including, the White House, Mount Vernon, the
Governor's Mansion in Annapolis, Maryland and the celebrated Orioles
Park at Camden Yards in Baltimore. When Tiger Woods and the rest of
the 1997 U.S. Open Tour strode the fairways at Congressional Country
Club in Potomac, MD, they were walking on grass fed with a composted
by-product. In Australia, composted by-products are also used on
public sites such as parks, golf courses, lawns and home gardens.

In conclusion, ViroSewage(TM) technology is a breakthrough technology
that compliments and optimises all the material flows and processes
associated with sewage treatment including final disposal.


For further information please contact Virotec International,
+ 617 5530 8014 or [email protected]


VIROTEC INTERNATIONAL LTD
ABN 81 004 801 398
PO BOX 188
SANCTUARY COVE QLD 4212
AUSTRALIA
www.virotec.com