Waste management scientists perform life cycle analyses in order to understand the complex process behind manufacturing a product – from design to disposal. Reporter Andrea Vasquez learns more from environmental consultant Jeffrey Morris via Google Hangout.
The best ways to reduce, reuse and recycle
When it comes to waste management, there's a lot of misinformation to sift through.
To get to the truth, scientists perform life-cycle analyses.
The LCAs follow the entire chain of events, from the manufacturing of a product to its disposal.
Reporter Andrea Vasquez learned more from environmental consultant Jeffrey Morris via Google Hangout.
Jeff, thanks so much for being with us.
Oh, glad to be here.
Can you tell us about these life-cycle analyses and how they're performed and what you're really looking at?
So, we have to look at all those stages of the life cycle of a product and, at each stage, evaluate what the emissions are, the environmental impacts.
So we look at, you know, greenhouse-gas emissions, criteria-air-pollutant emissions, toxic emissions, carcinogenic emissions, things that affect ecosystems, all that.
And then we have to figure out a way to roll all that up into indicators of environmental impact.
Carbon-dioxide equivalence is an indicator for climate-change impact.
And we have those kinds of indicators for other environmental impacts, like human respiratory disease or human toxicity or human carcinogenicity, also, ecosystems toxicity, nitrification of waterways, acidification of the air, and trying to start the develop ways to have indicators of habitat impact.
That's much harder, but people are working on that.
So, after we finish with a product, we have a choice.
Sometimes, it's throwing something away that's gonna end up either in a landfill or, in some places, in an incinerator.
Can you explain some of the pros and cons of landfills and incinerators for our trash?
When you get to the bury-or-burn statement, it depends on what the composition of the material is that's going into the incinerator or the landfill.
If you had all food waste, then it would probably be better to burn it, because, in a landfill, you would have to have a methane -- a landfill-gas-capture efficiency that's very high, like up in the 89%, to make carbon emissions from the landfill lower than the carbon emissions from the incinerator, which releases all the carbon, but in the form CO2, which is less of an impact than methane.
But food waste is really the exception.
If you're talking about wood as the other end of the biogenic-material spectrum, then you only need to capture about 10% of the landfill gases for your carbon profile or footprint of the landfill to be better than the incinerator.
So, in general, for the mixed garbage that you talk about putting into the landfill or the incinerator, even though you're producing electricity, that offset or that benefit is not great enough to offset the air emissions from the incinerator, because you're basically burning everything.
And even though you have a good pollution-control system, you still produce more emissions than if you landfilled that garbage with a decent landfill-gas-capture rate.
So, that's the kind of thing that you have to be aware of.
And if you're gonna build new facilities, like a new landfill or a new cell at a landfill versus a new incinerator, then, when you take into account the costs of those two and what you can do in terms of capturing the emissions, I think the landfill's probably better.
When we talk about these facilities, these landfills, and incinerators that are designed to efficiently capture and produce energy from that trash, how many of the existing facilities that we have -- landfills and incinerators -- would meet those standards?
The smaller landfills -- you might have an issue there, in terms of whether they're capturing the landfill gases and whether they're lined underneath to capture the leachate.
With the newer ones, they're required to have landfill-gas-capture systems and to be lined underneath so that the leachate doesn't percolate out.
Incinerators are required to mean the clean-air standards, so they should be doing a pretty good job.
So, what's our best option?
Our best option is not to dispose of it but, you know, to get the materials recycled, because we -- You save from, oh, 20% to 90% of the energy when you recycle material versus making a product out of virgin materials, you know, all the oil wells or the coal mines or the iron-ore mines, oxide mines, or the whatever you have to do to extract raw materials and refining them.
You avoid that when you recycle.
So, you save from 25% to to 95% of the energy that you would ordinarily expend if you made those products out of virgin content, instead of recycled content.
And then, environmentally, if you look at the climate impacts, you save from 50% to 90% of the greenhouse-gas emissions if you make your products out of recycled materials.
So, these are valuable resources and shouldn't go to the landfill or the incinerator.
They should be recycled.
So, I mean, I think it's a devil's bargain to talk about, you know, is it better to recycle or burn?
It's better to do neither and to set up your solid-waste-management system so that you can avoid disposing of things and, instead, reuse and recycle and reduce their use.
Right. And cut down on what's actually making it to that landfill or incinerator or --
Thank you for breaking it down for us and thanks for being with us.
Oh, you're welcome.
I hope that this has been informative for your viewers.