By Alex Mitchell, business development manager, Envac Dubai LLC
Imagine a city without waste collection trucks. We all want to live in a nice environment, but how many times have you been woken up in the early hours of the morning by the noise of these trucks? Or are you irritated by how fast they drive through your neighbourhood and the smell they leave behind them?
Believe it or not, it is possible to create a city where they become almost obsolete, a city with less noise, less traffic and less pollution. This is especially important because, by 2050, cities are expected to house approximately 70% of the human population, creating ever greater challenges to the way we manage waste.
Much of the comfort we take for granted today is supported by utilities that operate out of sight and often underground. Our potable water, cooking gas, district cooling, telecommunications, electricity and sewerage removal is mostly provided by a network of underground pipes and cables.
Solid waste management, however, has remained relatively unchanged and the disposal of waste on land still prevails in most of the world. Waste collection hasn’t changed much either apart from the horse and cart being replaced by fossil fueled trucks. Traditional waste collection requires bins that take up space and are unsightly, is labour intensive, unhygienic, increasingly costly and, most importantly, unsustainable as trucks travel millions of kilometres each day.
A holistic solution to waste management
One solution to all of these issues is the implementation of Pneumatic Waste Collection Systems (PWCS). Since the 1960s, PWCS have been collecting solid waste via networks of underground or overground pipes connecting inlet points at one end and collection stations at the other end. The system uses air to transport the waste at speeds of up to 70km/h through the network to a central collection station located up to 3km away from the farthest inlet.
Upon arrival at the collection station, waste is either temporarily stored prior to its removal for disposal and/or recovery or it is treated. Dry recyclables can be mechanically segregated ready for sale into the secondary materials market or food waste can be treated to produce compost and water. All of this can be achieved with minimal manual handling and within a fully sealed and hygienic system.
Reduced traffic issues
In areas where pneumatic waste collection systems operate, waste truck related traffic decreases by up to 90% with a corresponding reduction in emissions. For example, in a typical residential district with 3,500 apartments, waste collection trucks only need to spend 180 hours per year collecting waste from the Pneumatic Waste Collection Station. If the same development used traditional waste collection the trucks would spend almost 3,800 hours collecting waste from all the buildings, a huge difference. The reduction in truck movements makes neighbourhood streets safer and reduces the amount of emissions generated by these trucks.
It’s a reality
Envac, a Swedish company, is the global leader and inventor of PWCS. Founded in 1961 Envac operates over 1,000 systems in 30 countries and over 40 of these systems are in operation in the Middle East and India (ME&I). Envac installed the first PWCS in ME&I in Saudi Arabia in the 1970s and these systems are still in operation today.
Envac works to support the development of smart cities through embedding technologies that can be applied in large-scale developments, apartments, hospitals, commercial buildings, airports etc. The systems can significantly reduce labour costs long-term, reduce carbon emissions and eliminate a number of potential risks associated with increased waste levels and growing demands on this industry.
In the UAE, Envac’s longest running systems are at Jumeirah Beach Residence (JBR). Two separate systems have been in operation since 2007 and collect a combined total of 35 tons of solid waste each day from 36 residential towers, four hotels and over 100 restaurants.
The decision to implement Envac's PWCS at JBR saved the developer time, space and costs related to the manual collection of waste. Envac proved its flexibility by adding extra inlet capacity in 2011 to accommodate waste generated from additional commercial areas thatwere not anticipated when the initial design for JBR was undertaken. Four high capacity inlets were added that allowed these commercial units to access the PWCS without any need to expand the pipe network or collection stations.
Envac’s system continues to adapt to the ongoing changes at JBR as the development strives to maintain its position as one of the top attractions in Dubai (see box below).
As the disposal of waste becomes more costly, Envac is working with existing and future clients to design PWCS that maximises the source segregation and onsite treatment of waste in order to reduce landfill disposal and costs. The costs of handling waste will continue to increase as cities develop badly needed waste infrastructure. It is imperative that developments address the management of waste as early as possible within their designs and focus on implementing holistic waste management systems that turn rubbish into a resource.
Since 2007, the PWCS in JBR has: