An excerpt from the Brundtland Report “Our Common Future”, states:
‘Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.’
At H.I.Fraser, we take environmental awareness seriously and hence have actively targeted ways to support the building industry in supplying environmentally aware solutions for black and grey water collection, reuse and discharge. The range of our products and services covers the following domains:
Evac designs, manufactures and markets environmentally friendly waste and wastewater collection and treatment solutions for the building and marine industries worldwide. Evac offers a total wastewater management system for building and marine applications. Current technology and continued innovation is the cornerstone for EVAC’s international business and market-leading position.
The vacuum system is independent of gravity where the sewage is transported by air pressure instead of water and gravity. Water is used only for rinsing the bowl, not for transporting the waste. A vacuum system can also lift the waste vertically.
The Evac wastewater handling solution is a closed system, which consists of vacuum toilets, vacuum interface units, vacuum piping, vacuum collection tanks and wastewater treatment plants. The solution is based on vacuum, not gravity, which makes it possible to flush the waste horizontally or even vertically into overhead piping and if required, also around obstacles. The Evac solution is environmentally friendly. With low water
use – up to 80 % less than used in traditional toilets – it reduces sewage volumes and thus meets the requirement of small environmental footprint. The grey waters, originating from washbasins and being flushed through the Evac wastewater handling system, are clean enough to be used for irrigation or toilet flushing.
Because of their versatility and low water use the Evac applications can be implemented in numerous areas:
Supermarkets
Railway stations,
Airports,
Schools and universities,
Hospitals etc
Heritage Listed buildings,
High-rise Office towers
Shopping Centres
Exhibition Centres,
Prisons, etc.
The Evac solution minimizes the use of fresh water for toilet flushes. At the same time it offers you ultimate freedom of piping design. Additionally, the reuse of grey water contributes to a smaller water footprint at your building. The Evac vacuum toilet uses only 1.2 liters per flush as opposed to 6 -7 liters for the conventional toilet. This equates to a dramatic reduction in water consumption, savings in water rates and also a reduction in the amount of sewage produced. The Evac solution additionally makes it possible to recycle grey water for reuse as toilet flushing.
During each flush the Evac solution consumes 60 liters of air allowing the removal of viruses, bacteria and odors from the bowl and simultaneously enhances hygiene and personal comfort in the sanitary facilities. Each Evac solution forms a closed loop and this is particularly important in certain organizations, e.g. hospitals, research facilities and prisons, where the waste must be contained or is considered high-risk.
As conventional toilet consumes seven litres of water every time it is flushed the Evac toilet uses just over one litre of water per flush.
Evac gives the building designer complete freedom from the restrictions of gravity fed pumping. Bathrooms and toilets do not need to be tied into a services core but can be located where they best suit the design.
Evac system offers space planning freedom. In speculative buildings, a prospective tenant will often wish to plan the space available in a building to suit its business operation. The Evac system gives him/her the extra capability. Final decisions on the floor plan can be delayed leaving maximum room to manoeuvre and giving the client maximum flexibility to plan space.
One of the main benefits of installing an Evac system is the real cost savings that can be made. The time required to design and install an Evac system is significantly shorter than the time needed for traditional gravity systems. This reduces on site costs and helps meet construction deadlines.
Evac’s vacuum toilets are significantly cleaner than conventional toilets, which permit bacteria and odours to
enter the atmosphere. The Evac toilets enhance both hygiene and personal comfort within washrooms by using up to 60 litres of air with each flush, removing viruses, bacteria and odours from the bowl. By encouraging the cycle of air, washrooms will stay ventilated and fresh. Every Evac vacuum system is a closed loop that is kept under a vacuum at all times, which makes it impossible for pests to live and breed in the drainage, and securely contains all and any waste. This is imperative – especially in facilities with a high risk of contamination such as hospitals, prisons and research facilities.
A building’s water consumption is dependent on a number of factors: the size, the type, the function, and the installed drainage system. The following examples concern a building with 100 toilets and an average of three flushes an hour per toilet.
Special Low Flush Gravity Toilets
· Water consumption: 6 litres/flush
· 100 toilets x 3 flushes/hour x 6 litres/flush = 1800 litres/hour
Evac’s Vacuum Toilets
· Water consumption: 1.2 litres/flush
· 100 toilets x 3 flushes/hour x 1.2 litres/flush = 360 litres/hour
Total amount of saved water: 1440 litres/hour → 80%
Evac’s vacuum system dramatically reduces water consumption by 80% per hour.
Since Evac’s vacuum toilets are purely pneumatic, no electrical connections are required. The whole system is operated by a Vacuum Collection Unit, which creates and maintains the vacuum, and is the only part of the system that consumes energy.
· A vacuum toilet uses 60 litres of air per flush at an operating pressure of -0.5 bar
· 100 toilets x 3 flushes/hour x 60 litres/flush = 18,000 litres/hour (at one atm)
· 18,000 litres/hour → 18 cubic metres/hour
· 18 cubic metres/hour x 2 (for operating at -0.5 bar) = 36m3 cubic metres
· A 100 cubic metres/hour range vacuum pump is rated at 2.2 kilowatts
The pump’s operating time is 21.6 minutes per hour consuming only 0.792 kilowatts
Data collected from various projects give us an average power consumption of 1 kilowatt hour. The system’s design, operating conditions, control panel and discharge function of the Vacuum Collection Unit has been taken into account. If the system is used less frequently, the hourly power consumption will drop accordingly.