Don’t waste sewage – it’s a resource

The way we treat sewage needs to undergo a revolution on the same scale as we have seen attitudes change to household rubbish and industrial waste.

That was the core message of an event hosted by consultants Aqua Enviro this week.

While the value of most other resources is widely recognised, we tend to have a devil-may-care attitude to water consumption in the UK, perhaps in part due to the climate.

The current wastewater treatment regime does almost exactly what it says on the tin – it wastes water.

Aqua Enviro’s Dr Nigel Horan told delegates at Thursday’s event that while technology may have moved on, there has been no real change in the way we look at sewage for generations.

We need to look at sewage as a resource, rather than a waste product to be simply got rid of, he said.

“[The system] was put in place in Victorian times and had a function – to get solids off the street because people were dropping down dead from diseases,” he said.

“We’ve done that quite effectively but we’ve not had much in the way of innovation for the past hundred years.”

He argued that water companies were not just throwing money away, they were paying to throw money away.

More water metering, widespread use of sludge in energy-from-waste generation and the extraction of marketable chemicals would all help realise the true value of wastewater, he said.

A case in point is phosphorus, he said, a chemical found in abundance in raw effluent with a market demand is on the doorstep.

“Fertiliser manufacturers in this country can only meet about 40% of the demand each year because they don’t have the phosphorous,” he said.

“There’s enough phosphorous in wastewater to meet the whole of the demand.”

The industry needs transforming, he said, and we need to tap into the resources that are currently being horribly wasted.

Sam Bond

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