Sewage tech lets companies sort profit from Dubai poo

By Jonathan Frewin
Business reporter, BBC News, Dubai

image captionFilthy lucre: Over the last five years Dubai has used technology to transform how it deals with the contents of the region's toilets

Mohammed Abdulaziz Al Awadhi is a man passionate about human waste.

He's been involved in Dubai's sewage treatment for a quarter of a century, and is now director of Dubai's sewage treatment plants.

In a crisp, white, immaculately clean dishdasha, or full length robe, he cuts a slightly incongruous figure at the city's Jebel Ali sewage treatment plant.

Around three-quarters of the waste processed there arrives through Dubai's network of sewers.

But still, around a quarter arrives in giant orange tankers, coming from labourer accommodation, mostly on the outskirts of the city.

image captionWood, plastics and other solids are removed from the sewage

It's the start of a process that turns out a number of by-products, including refined water that is used for agriculture and horticulture.

Where there's muck

Mr Al Awadhi says this is the only way the city can afford to keep parks and green spaces growing so vibrantly.

"Potable water in this part of the world is a commodity which is produced and desalinated and the cost to the government is roughly two dollars per cubic metre," he says.

"Compare that to waste water which is produced from our sewage treatment plant which is costing about half a dollar per cubic metre."

image captionOnce the solids are removed the liquid sewage undergoes a series of biological and mechanical purifying processes

"This water makes it economically feasible to ensure that we have such a wide spread of horticulture and agriculture in the city."

media captionWATCH: The BBC's Jonathan Frewin visits Dubai’s Jebel Ali sewage treatment plant

Of course human waste contains quite a lot of nutrients, and once waste water has had plastics, wood and other solids removed, it goes through a range of biological and mechanical processes that keep the treatment plant - amazingly - virtually odour-free.

"Due to the sudden rapid growth of the city, the issues were with the tankers being queued in the long queues, some locations they had to wait up to 40 hours," says Mr Al Awadhi.

"Apart from that because the plant was overloaded, the final product was not meeting exactly the design requirements. And it was discomfort to the public."

image captionRespect the queue: Just five years ago Dubai had only one sewage treatment plant, leaving tankers waiting outside for up to 40 hours

But the economic slowdown, which reduced sewage production, combined with fast-tracking construction of the Jebel Ali sewage treatment plant, meant the city finally had a sewage treatment system that could overcome those challenges.

Smell of success

But it's not just about centralised sewage treatment in this part of the world.

image captionSewage has created a home for dragonflies and wildlife

On the outskirts of the city sits a desert jungle where brightly coloured dragonflies mingle with rare birds. This is the Al Barari residential community of about two hundred homes which has its very own sewage treatment works.

The output from that is mixed with water from the government plants, and then put through a further process to ensure the water in extensive waterways around the development doesn't get clogged up with algae.

"It's a sustainable development. I think the vision of the developers was to have a closed loop for their water cycle they wanted to be able to use in their greenery," says Concorde Corodex's director of business development, Mohanned Awad.

"Having a system that's portable and mobile was also important, they wanted to minimise both the footprint and the installation time."

image captionThis development of just 200 homes has its own sewage treatment works, which feeds the garden water system

Concorde Corodex is a local company but has been experiencing success exporting its products across the entire region.

"We've exported into basically all regions of the Middle East, North Africa, we have systems in Nigeria, Ghana; we were asked by the United Nations to deliver systems in Sudan," says Mr Awad.

"We have systems in Oman, Yemen. Basically, any area which is a residential area that usually has a septic system or a rural area will look towards a packaged system as a solution to treat their sewage, just because of ease of installation, and ease of operation," he says.

"The science behind these systems is usually in the biology, but the mechanical components are actually very simple to operate and can be done by simple mechanical operators."

Pure science

It's possible to process the water to even higher levels for other uses.

"There's other technologies we've used... called MBR or membrane bioreactor technology, that will actually treat water to a potable state," says Mr Awad.

image captionProcessed sewage sludge is made into fertiliser and sold

"We're not suggesting you drink it, there's actually a lot of applications for ultra purified water, processed water for cooling, water for processes in industrial areas. The applications are really varied, and the technology does exist to treat water to very high levels."

Back at the main sewage treatment plant, there's another by-product which might come as a surprise.

Sludge that was separated from the incoming water gets baked and dried using methane gas which is yet another by-product of the treatment process.

Granules then get bagged and sold to gardeners all across the city as a fertiliser of human origin; a bargain, perhaps, at $2.50 for 25kg.

And clearly demonstrating that in the end, very little to do with waste water in this part of the world, actually goes to waste.