Bin day is approaching and you’re about to tip a pile of bubble wrap, shredded paper, plastic food trays, and cling film into your recycling wheelie bin.

Stop right there!

Richard Brown, the operations manager at Suez Recycling and Recovery UK at West Sleekburn, and Sheila Johnson, Northumberland County Council’s senior waste management officer, will be shaking their heads with disapproval.

And understandably.

Everything we put in our black recycling wheelie bins in Tynedale ends up at the plant. But all the above items cannot be recycled there and should instead be put in with the general rubbish. This will then get incinerated at an energy from waste facility at Stockton which produces electricity – a better option than landfill.

On a tour of the facility, it is only too evident how many of us are getting it wrong and that means the clever system of sorting the waste out into its various components has to work even harder.

Throughout the plant, there are bins and chutes marked as ‘residue’, where everything that should never have arrived in the first place goes.

And much of the sorting is done by hand, as well as a series of infrared sorters which can be programmed to pick out different materials, like newsprint. Magnets collect steel cans and non ferrous magnets the aluminium cans.

And a huge rotating cylinder, called a trommel, with different sized holes in it, sieves items into different sizes, before lighter items are sucked away by through an air tunnel.

The plant is run from a central control room where a computer monitors each section to ensure everything runs smoothly.

And it would run even more efficiently if non-recyclable rubbish didn’t get put in with the mix.

Cardboard, newspapers, magazines, food and drink cans and aerosols are all welcome, but when it comes to plastic, that scourge of the planet, things become a bit trickier.

Sheila explained that plastic made from material called HDPE and PET – basically plastic bottles – were highly recyclable with a good market value.

But low grade plastic, like carrier bags, food trays, plant pots and yogurt pots were no use.

“With yogurt pots, the market is virtually non-existent,” she said. “The energy it would take to recycle a yogurt pot has no environmental benefit.”

Plastic bottles, on the other hand, get turned into pellets which can be melted and injection moulded to create new products. The plastic can also be used to make jumpers and fleeces (think polyester).

An acid test to try at home, said Sheila, was to squash the plastic. If it bounces back like a food tray or a crisp packet, it’s no good.

But there’s an even worse ‘non-target material’, that turns up at West Sleekburn – food waste.

And when this is discovered, the whole load has to be discarded. More unsavoury items that cause contamination are the bags of dog faeces and even dead pets.

The result is 20 per cent of everything that arrives has to be sent to Stockton for incineration.

As Richard put it: “Every fifth wagon that turns up here might as well go past my gate.”

Nevertheless, the plant still manages to recycle 44,000 tonnes of waste every year, 20,000 tonnes of it from Northumberland.

And change is on the horizon with a new Resources and Waste Strategy (WRAP) which aims. among things, to make manufacturers pf plastic pay more for the recycling process.

There’s also a hierarchy, said Sheila, to tackle the environmental impacts of our rubbish, which we can help with at home.

The best option is ‘reduce’– by buying fruit and veg loose rather than wrapped in plastic. Next comes ‘reuse’ – making use of old containers or give away things to charity. ‘Recycle’ comes third in the list, followed by energy from waste where electricity is produced by burning waste. At the bottom of the table is landfill.

Mountains of cans, paper, card and squashed plastic at the end of the line at West Sleekburn show what already is being done, so when you next buy a can of drink, make sure it doesn’t end up with the normal rubbish.

“Aluminium is high value,” explained Sheila. “Every can saves a square metre of rain forest because you are not digging up the rain forest to get the minerals to make a new one.”