These are general statements, which refer to the entire Hybrid
Toilet System range
1. HOW DOES THE SYSTEM WORK?
2. IS THIS SYSTEM LIKE A DRY COMPOSTING
3. CAN GREY WATER BE ADDED TO THE UNIT?
4. WHAT WILL HAPPEN IF THE SYSTEM IS UNUSED?
5. DETAILED SYSTEM DESCRIPTION
6. CAN ANYONE TOUCH THE WASTE OR CAN ANYTHING
7. WHAT WOULD HAPPEN IF THE UNIT WAS FLOODED?
8. DO THE UNITS SMELL?
9. CAN THE TOILET BE INSTALLED IN A NEW
OR EXISTING DWELLING?
10. HOW DO I REMOVE RUBBISH FROM THE
11. CAN I COMPLETELY BURY THE TANKS?
12. CAN THE SYSTEM BE INSTALLED ABOVE
13. HOW DO I SIZE A UNIT?
14. HOW MUCH SLUDGE IS GENERATED BY ONE
15. HOW IS THE SLUDGE REMOVED FROM THE
16. DO I NEED A PLUMBER TO INSTALL THE
17. CAN ADDITIVES BE INTRODUCED TO THE
SYSTEM TO IMPROVE THE DIGESTION PROCESS?
18. CAN THE HYBRID TOILET SYSTEM HANDLE
19. HOW WILL THE HYBRID UNIT HANDLE HIGH
20. WHAT WILL HAPPEN IF THE SYSTEM IS
1. HOW DOES THE SYSTEM
Simple system description.
In simple terms the system consists of a MicroFlushing or
a non-flushing, drop toilet, feeding directly into a primary
treatment tank filled with water, which then delivers via
displacement, clarified effluent to the secondary treatment
unit. On completion of treatment the effluent is then dispersed
to ground via a gravel bed.
2. IS THIS SYSTEM
LIKE A DRY COMPOSTING TOILET?
No, this is a wet system.
Upon installation the tanks are totally filled with water.
The constant addition of waste to the system will result in
a flow of treated effluent through and out of the system by
displacement. If 10 litres went in, approx. 10 litres will
be displaced through the unit.
3. CAN GREY WATER
BE ADDED TO THE UNIT?
No, additional waste water.
The addition of extra loading from other sources into the
hybrid unit is not recommended. The system is designed to
operate around the volumes generated by the population using
the system as a toilet only. Waste from hand washing facilities
may be introduced at the effluent exit point of the unit.
This would require an extension of the gravel bed to cope
with the extra volume of water generated. This would be subject
to approval by your local authority.
4. WHAT WILL HAPPEN
IF THE SYSTEM IS UNUSED?
Dependent upon certain environmental conditions a certain
percentage of water could be evaporated out of the system.
In periods of very low or no use, the level of evaporation
may exceed the incoming volume.
Should the unit sit unused for a period of, for example three
months, the liquid volume in the unit would drop. The amount
of evaporation that will occur is entirely dependent upon
the climatic conditions. Once the unit is in service again,
the liquid level in the primary tank will rise until the tank
is full and then flow through to fill the secondary tank over
time, displacing well treated effluent into the gravel bed.
If the unit was unused for even longer periods, some water
could be added to the system but would not be required unless
the water level was extremely low. It is not necessary for
the unit to always be entirely full, because treatment will
still occur while there is waste to be digested. After a long
no use period the system will restart upon the introduction
of fresh waste.
5. DETAILED SYSTEM
Primary Tank (refer general
The process begins when the waste drops down the dropper tube
into the primary tank. Due to the very small volumes entering
the primary tank the detention time in the system is as long
as 83 days or longer dependent upon usage.
This extended period of detention allows for very effective
breakdown of the solids and very efficient settling and clarification
to occur. The remaining undigested solids settle out to the
bottom of the unit to form the sludge layer. As use continues,
the sludge volume will increase until it begins to impact
on the detention time of the effluent.
Dependent upon usage, it will normally be years for this
level to be reached. This volume requirement and sludge level
is established and controlled through the use of a sludge
gauge, which is supplied with the unit. The management of
the sludge is discussed in more detail in subsequent paragraphs.
As in a normal septic tank this sludge is acted on and broken
down by anaerobic bacteria.
Another benefit of the long detention time is the containment
of parasites in the primary sludge. Parasitic eggs have a
settling rate in a column of water and these settling rates
have been established by studies conducted by the World Bank.
The detention time in the primary tank is long enough to capture
the majority of these parasites thus creating a very efficient
barrier against re-infestation.
The effluent that has entered from the primary tank is now
directed along a very specific flow path. The design of the
flow path is such that it eliminates the possibility of short-circuiting.
The majority of the secondary tank and its in-built baffling
system is filled with a polyethylene media which supplies
an extremely high surface area to volume ratio.
This media has been designed specifically for this process
and has a high void space design to prevent clogging. Loadings
entering the secondary system are well below the anti-clogging
maximums for gravel bed wetlands. It is designed to easily
cater for the loading delivered from the primary tank with
a high built in safety margin. This is of extreme importance,
so as to ensure absolute minimum maintenance, if at all.
Secondary Tank Flow Documentation
Another feature of this area is the unique flow path that
the effluent must follow. Upon entering the secondary tank,
the effluent is introduced into a series of descending, ascending
and circular flow paths. The effluent must also travel through
the extremely intricate flow path created by the plastic media,
which guarantees maximum diffusion and mixing. This intricate
and very specific flow path ensures that the effluent is in
maximum contact with the bio-film at all times. This large
contact area and long contact time allows for attacking of
the remaining pathogens in the system by the bio-film bacteria.
As the effluent flows up and down through these zones it
is also subjected to aerobic, facultative, and anaerobic treatment
zones on four separate occasions which will also contribute
to the kill rate of the pathogens. When the treated effluent
completes this process it then exits the system and is sent
to ground via a gravel bed. Because of the very small volumes
of liquid and the quality of the effluent exiting the unit
there is minimal impact on the surrounding environment. This
then completes the treatment process.
6. CAN ANYONE TOUCH
THE WASTE OR CAN ANYTHING GET IN?
No, this is a closed system.
At no stage during the process is the effluent exposed to
human contact. The system is sealed with the only access being
the waste delivery point and the vent. The system is designed
to function in a high water table area with the secondary
tank outlet above ground level. The system is not designed
to be buried, as this would allow entry of unwanted extra
water into the treatment zone. The closed system also prevents
clogging from occurring by plant root intrusion, excessive
algae growth, and insect infestation.
7. WHAT WOULD HAPPEN
IF THE UNIT WAS FLOODED?
Should the unit become inundated by water the air space of
the tanks will completely fill. As the flood waters recede
below the outlet point and presuming the unit is still intact,
the extra liquid will drain out and the unit would be immediately
8. DO THE UNITS SMELL?
The MicroFlush unit has an inbuilt 5mm deep waterseal created
by a counterweighted Stainless Steel flap.
This effectively stops any air flow coming back into the toilet
bowl. A rotary ventilator is installed on the vent pipe to
create a small negative pressure.
The NonFlush unit is also a closed system that allows for
very specific control of air movement. Fresh air is continuously
drawn down the toilet opening ensuring that any odor generated
is expelled out the vent pipe. Remote applications are supplied
with a solar panel, 12 volt fan and battery backup arrangement.
For installations in domestic dwellings, we supply a small
low voltage fan which is designed for continuous operation.
This could be either mains powered or solar with battery back
Strong odor emanating from the vent pipe is an indicator of
an imbalance in the system. See the information on additives
in section 18.
9. CAN THE TOILET
BE INSTALLED IN A NEW OR EXISTING DWELLING?
As long as there is sufficient height under the floor of the
building the unit can be retrofitted to an existing building.
For actual height requirements, please contact your nearest
agent and ask for General
Arrangement Drawings for the system size your require.
Excavation depth and width requirements will also be needed
for correct assembly of the unit.
For new dwellings, please contact your nearest agent
for General Arrangement Drawings for the appropriate
10. HOW DO I REMOVE
RUBBISH FROM THE SYSTEM?
Access is provided in both the primary and the secondary tanks.
The main access points are in the primary tank. These hatches
are where the removal of the sludge takes place and removal
of any foreign objects that have been placed in the unit.
Flooding of the primary tank, due to a blockage is nearly
impossible due to the design of the outlet junction and baffle.
See drawings for details.
The MicroFlush option limits the introduction of foreign waste
into the units.
11. CAN I COMPLETELY
BURY THE TANKS?
No, refer to tank installation.
We do not recommend burial of the tanks to a greater depth
than shown on the general arrangement drawings. Burial of
the tanks will allow intrusion of ground water into the unit.
Consult the manufacturer for special circumstances.
12. CAN THE SYSTEM
BE INSTALLED ABOVE GROUND?
The primary tank may be placed on top of the ground or elevated
on a platform, but as shown the secondary tank must be installed
lower than the primary tank to allow for gravitational flow
to occur from tank to tank.
13. How do I size
When sizing a hybrid toilet unit refer primarily to the Hybrid
Unit size calculator
This is the most accurate method of calculating unit sizing. All
unit sizing should be done in conjunction with trained Hybrid
Toilet Representatives. The average person is not qualified
to size waste treatment units. Each individual site
must be assessed on its on merits looking closely at
the circumstances that surround that particular site only.
There is no such thing as a generic sized unit.
Never under any circumstances take a yearly average figure
and size the unit based on that information alone.
Things to consider.
Factors that must be considered when sizing a unit is the
type of the clientele using the unit, the type of use of the
system (eg. day use area, camping area and combined use),
fluctuations in loading and temperature. The travel distance
from staging points has a bearing on use rates as well.
Growth rate Allowance.
Something that mostly is forgotten about or is not considered
is the growth rate that may occur on the unit loading. Hybrid
Toilet units properly installed will last for decades. Some
areas like the World Heritage area of Fraser Island in Queensland are
undergoing growth rates of around 5% per year. When this
is calculated out over time the effect can be substantial.
It may be appropriate to allow for say 10 years of growth
and plan for additional systems or upgrades as you approach
that length of time.
Capped Visitor numbers.
Where circumstances allow it is ideal if visitor numbers can
be capped. Controlled visitor numbers allow for more accurate
Size calculations to occur. If this is the case then there
is no need to build in percentage growth figures. Capped visitor
numbers allow planning of minimal impact on the site.
The utilisation of door counter systems allows the tracking
of unit usage rates. These figures can be recorded on data
bases and analysed against unit performance.
All the above points have potentially a significant bearing
on the units performance. It is prudent to allow for
around 25% extra capacity when calculating a rating.
The Hybrid Calculator does this automatically. This
gives an allowance for unknowns.
Unit size driver.
If you have a particular period of the year where visitor
numbers peak for a couple of months, work on these figures
only and discount the remainder.
This is particularly important as under sizing the unit capacity
at the beginning can create long-term management and environmental
Large short duration spikes measured in a couple of days only
will have little effect. It does become significant when
the loading stretches out past this period.
Ideally with a little forward planning Porta Loos or the
like should be brought in to carry significant spikes for
once off events.
Decisions on unit sizing based on cost alone initially
may seem prudent, but in the longer term the cost of an under
capacity system will far outweigh the presumed initial cost
14. HOW MUCH SLUDGE
IS GENERATED BY ONE PERSON?
This is dependent on diet, cultural considerations, temperature,
and many unknowns; hence fecal volumes may vary. The introduction
of Biological additives will assist in controlling sludge
15. HOW IS THE SLUDGE
REMOVED FROM THE UNIT?
Guidelines for sludge removal and disposal.
There are two options available for the removal of sludge
and they are subject to local Authority and or the controlling
Authority's approval. Generally, if access can be gained by
a licensed waste removal contractor, sludge should be removed
in this manner. If this is not possible due to remoteness
of location or accessibility, consult your Approving Authority
for their recommendation on sludge disposal.
In all cases the relevant approvals must be sought prior
to the installation of the Hybrid Toilet System. Removal of
waste by other than licensed persons in some states may be
16. DO I NEED A
PLUMBER TO INSTALL THE UNIT?
Installation should be carried out by and under the supervision
of licensed persons. If a licenced person is not available
please consult with your agent.
17. CAN ADDITIVES
BE INTRODUCED TO THE SYSTEM TO IMPROVE THE DIGESTION PROCESS?
Investigation has shown that the addition of products such
as Bio Magic and Bio Magic (available from your nearest Tradelink
store) are beneficial.
These products offer benefits in terms of odour control,
cleaning of the water column and long term control of sludge
volumes. A small amount of these products used as part of
the general cleaning process will assist in balancing the
biological process of the system.
Lysofos has also been used with success.
18. CAN THE HYBRID
TOILET SYSTEM HANDLE AN OVERLOAD?
Yes, overload situations.
A major criterion of the systems design, is that the unit
must be able to accept fluctuating loadings, both hydraulic
and organic. The environment in which some of the units will
operate can be subject to highly variable loadings. For example,
National Parks which can receive substantially higher visitations
over weekends and holiday periods.
The exceptionally long detention time enables the system
to buffer the high loads. However there is a point where effluent
quality and system performance will begin to diminish. There
is no substitute for correct unit sizing in the beginning.
19. HOW WILL THE
HYBRID UNIT HANDLE HIGH HYDRAULIC LOADINGS?
Unlike septic systems, which will deliver very high hydraulic
loadings in an overload situation, the hydraulic loadings
on the Hybrid Units are very small by comparison under the
Unlike compost systems that rely on quite controlled moisture
levels the Hybrid unit is designed for high liquid loadings.
Being a wet system high liquid loadings are not of great significance.
20. WHAT WILL HAPPEN
IF THE SYSTEM IS OVERLOADED CONTINUOUSLY?
Extreme overload situations.
Major overloading for long periods and continuous overloading
will result in three main problems.
- There will be a significant reduction in effluent quality.
- There will be a major buildup of floating material on
the surface of the primary tank resulting in waste backing
up into the dropper tube.
- There will be strong odour emanating from the unit.
In light of the above it should be clear that careful consideration
needs to be given to the sizing of the unit in the design
stages to ensure that all the benefits of the Hybrid Toilet
System can be fully appreciated.