What a waste (Day 124)

Green recycling binA few years ago the ‘waste’ business was estimated to be worth around GBP 272 billion (EUR 300 billion Euros or USD 410 billion).

The study also estimated that the world was producing at least four billion metric tons of waste a year – equivalent to world production of grain and steel combined.

These figures didn’t include construction, mining, agricultural and forestry wastes – suggesting that the real figure is much larger.

They are huge numbers and will grow as our population increases and we get better at recycling and managing our waste.

The data was published in a 451-page report, called From Waste to Resource – an abstract of world waste survey 2009′, by Catherine Gaillochet, a legal expert specialising in environmental law, under the direction of Philippe Chalminat at Paris-Dauphine University.

One of our challenges is to find a use for all the waste we produce, especially for our energy needs. At present, globally, we don’t have enough facilities and there are technical issues to resolve.

A UK Government report in 2008 highlighted some of the issues. It said: “While recycling and energy markets for clean, virgin wood have been growing
in recent years, waste wood has been a largely overlooked resource.

“This is in part due to it often arising as part of a mixed waste stream, with limited
availability of facilities for its segregation, and also a result of its predominantly
contaminated nature, which often makes recycling impractical.

“With around ten million tonnes of waste wood being produced in the UK each year, most of which goes to landfill, this is a great missed opportunity.”

There is still clearly a need for more innovation in how we use our waste and I was interested to read a story last week about how ‘plant waste’, albeit indirectly, is being used to help energy production.

Researchers at UTSA and the Southwest Research Institute (SwRI) have determined that biochar, a substance produced from plant matter, is a safe, effective and inexpensive method to treat flowback water following hydraulic fracturing, or fracking.

Flowback water treatment is a critical sustainability issue for the oil and gas industry.

One to five million gallons of water mixed with sand and chemicals are required for the fracking of each well. Once the water is used, the flowback, or wastewater, must be treated to remove hazardous chemicals before it is stored, reused or disposed, which can be a costly endeavor.

CharcoalBiochar is a stable charcoal-like solid that attracts and retains water. It can absorb impurities such as hydrocarbons, organics, biocides and certain inorganic metal ions.

It is made from materials such as wood chips, paper, leaves, soybean oil, corn oil and other forms of agricultural waste heated to high temperatures in an oxygen-deprived environment.

Currently, biochar is used commercially to improve soil quality by helping soils retain nutrients and water

However, using biochar could help oil and gas companies save money and responsibly treat flowback water for reuse. This is particularly important in areas where water resources are scarce.

One of the research team includes senior research engineer in the SwRI Chemistry and Chemical Engineering Division Maoqi Feng.

He says: “This project extensively studied the adsorption capacity of different biochar for potential inorganic ions and organic contaminants. The adsorption capacity data is very useful for designing of large scale adsorption beds for flowback water treatment.”

The research team developed the preparation method, tested the process and collected data that shows the exact type of biochar that filters out the specific chemicals oil and gas companies add to the water during the fracking process. Some of the these chemicals, such as calcium chloride and magnesium chloride, are known to be harmful to the environment.

All of these interesting developments, involving chemical engineers, are contributing to a more sustainable planet. Commercially too, it shows how chemical engineering can make valuable products from what was once perceived to be worthless waste.

2 thoughts on “What a waste (Day 124)

  1. Sounds good but what do you do with contaminated biochar?

    It would be great if the contaminated biochar could still be used to improve soils since the contaminants within it could be slowly broken down and in small quantities may be useful nutrients.

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