Waste transfer stations were traditionally designed to bulk up and compress wastes in the most efficient way possible, so that they could be cost effectively transported to a landfill site in larger vehicles. This enabled the waste collection vehicles, which are designed for stop/start operation, but not long haul, to continue their collection runs after disposing of their loads. Therefore little thought was given in terms of space or logistics for resource recovery.
This has been changing as recycling has been developing and most new transfer station designs, especially in rural areas, have designated bins and areas for resource recovery activities for. Pricing policies enable residential and some small commercial customers to dispose of separated materials at reduced or zero cost. The price differences between segregated wastes and mixed waste disposal encourage customers to separate their wastes before arriving at the facility. The variety of solutions adopted by regional councils in NSW and elsewhere are outlined in references such as the Handbook for Design and Operation of Rural and Regional Transfer Stations published by the Department of Environment and Conservation (NSW)Error: Reference source not found
Many transfer stations are located on or within the boundaries of former landfills. If the constructed over an old landfill site, the design must also consider ground stability and differential settlement. Innovative design and construction considerations have been built into facilities located on former landfill sites to allow for ground movement, requirements for raising buildings and structures off ground-level and landfill gas vents.182
There is no standard for waste transfer station buildings. Design trends however are heading towards simplifying and standardising facilities. As an example, open and open-sided buildings are often preferred because they save costs on materials such as roller doors and there are fewer structures for vehicles to hit, reverse into or otherwise damage.
Modern transfer stations not only also include drop off facilities for a range of recyclable and recoverable materials but often a suite of waste-related features such as areas for customers to drop off hazardous materials such as e-waste and chemicals and potentially reusable materials such as timber, bricks, second hand toys, bric-a-brac, books and homewares, education and awareness centres and materials recovery facilities. In some cases, a contract is let for a second hand business to operate at the site with scavenging rights for the operator included in the contract.
Depending on the size of the transfer station, customers can deposit directly into bins or pits, or into a separate open area that is swept by a loader or other plant.
The most important part of a transfer station is the circulation pattern. This allows collection vehicles to move quickly and safely through and out of the facility.
Other important design elements include:
Having one or more queuing lanes before the weighbridge to accommodate traffic;
Electronic recording of exact type and quantity of materials disposed of;
Consistent application of fees by load weight;
Ability to set and change fees for different waste types;
Greater understanding of type and volume of materials deposited; and
Increased possibility to identify opportunities for improved resource recovery.
Hand-held data recording devices can also used as an alternative to a weighbridge at small sites to record waste quantities, types and fees and issue customers with receipts.184
Vertical Transfer Stations
In the 1980s, Netherlands-based NCH Hydraulic Systems developed a vertically operating waste transfer station. The system works by waste being deposited in the top of a vertical container. The weight of the materials deposited provides compaction. The main advantage of the system is that it saves space.
A number of vertical transfer stations are operating in the Netherlands, Australia, the Caribbean, Turkey, Chile, China and Malaysia, with capacities ranging from 350 to 7,000 tonnes per day. The Jingan District Waste Transfer Station in the centre of Shanghai is one of these and handles about 400 tonnes of waste per day. The world’s largest vertical transfer station is in Santiago de Chile. This transfer station handles 6,000 to 7,000 tonnes per day and up to 10,000 tonnes in peak-periods.185