Why do we recycle paper?

August 11, 2008 5:27 PM

Why do we recycle paper?

I totally understand the recycling of glass and plastic and all that. But I need to understand why we recycle paper. Doesn't it - quite literally - grow on trees? If we discard it and bury it in the ground, doesn't it break down? Why do we need an industrial process - which seems infinitely more ugly and harmful - to get rid of a naturally occurring substance?

The smarter part of me thinks the answer might be in the ink and the printing process, and the cynical side of me thinks we've been lied to by people who have some kind of interest served by building big recycling facilities, rather than exploring bio-safe inks. But there must be something I'm missing here ... isn't there? Is there some factor I'm not factoring in?

I've watched both Al Gore and Penn & Teller; I've read propaganda on both sides of the issue. Logical explanations (and corresponding links) are earnestly welcomed.

posted by jbickers to science & nature (29 comments total)

Because we use paper faster than trees grow. Because chopping down trees has serious environmental impacts to local wildlife.
posted by dirtynumbangelboy at 5:31 PM on August 11, 2008 [2 favorites]

Making paper is a very polluting process, more so than the recycling of paper, and paper takes up a lot of space in landfills.
posted by Foam Pants at 5:33 PM on August 11, 2008 [2 favorites]

If we discard it and bury it in the ground, doesn't it break down?

Just a quick note: items discarded in modern landfills generally do not break down. These days, landfills are completely sealed to prevent leaching of contaminants into the groundwater and soil. They're essentially huge plastic sacks, and once they're filled with garbage, they're done for good.

Paper can be burned or composted rather than landfilled, however.
posted by mr_roboto at 5:35 PM on August 11, 2008

From Carnegie-Mellon's Green Practices (first hit on google for "why recycle paper"):

1 ton of paper recycled saves:
17 trees
275 pounds of sulphur
350 lbs of limestone
9,000 lbs of steam
60,000 gal of water
225 kilowatt hours
3.3 cubic yards of landfill space
posted by scody at 5:35 PM on August 11, 2008 [7 favorites]

Because we use paper faster than trees grow.

This simply isn't true.
posted by mr_roboto at 5:39 PM on August 11, 2008

You haven't cracked the wikis, yet?

Paper Pollution
Paper Recycling
posted by cowbellemoo at 5:45 PM on August 11, 2008 [1 favorite]

On the ink topic, soy inks are some of the most common inks used (almost all newspapers, for instance). They're many times greener than petroleum based inks, though aren't totally green because the pigments and additives are similar or the same as those used in oil inks.
posted by pedantic at 5:47 PM on August 11, 2008

This simply isn't true.

Ermmm.. actually it is. If it weren't true, we wouldn't be doing new logging for paper.
posted by dirtynumbangelboy at 5:58 PM on August 11, 2008

"I totally understand the recycling of glass..."

If you understand glass recycling, then you should certainly be able to wrap your mind around recycling papers. Glass is a non-toxic substance that doesn't leach into groundwater when it is buried, and it eventually turns back into it's original substance. While some will debate that we're running out of trees, few will debate that we're running out of sand. In addition, glass is heavy, so it takes more fuel to transport it to MRFs.

Coincidentally, I'm considering starting a curbside recycling business in my town and have been surprised to learn that many curbside recycling companies don't accept glass because, comparatively, the cost/impact ratio is just too high compared to other materials.
posted by stuboo at 6:00 PM on August 11, 2008

what always worries me, and perhaps what you're implying, is that it seems like a good idea to bury paper (especially if mr_robot is right) because it's transferring CO2 from the atmosphere.

from this report (table 1) it seems that energy "costs" about 2 pounds of CO2 per kwh.

scody says that recycling saves 225kwh of energy. that's about 450lb, or 1/4 a ton of CO2.

so, if you didn't recycle, you would stick that ton of paper in the ground. since it comes from trees that's effectively moving a ton of CO2 from the air and sticking it in the ground (i am ignoring water, but it turns out photosynthesis is pretty efficient: you generate C6H12O6 from 6xCO2; that's 6x12+12+6x16=180 from 6x(12+2x16)=264; the hydrocarbon in a tree is actually concentrated CO2, and we're using the dry paper weight, which is going to be lower in water than wood in a tree).

so yeah, it does seem like the argument from CO2 alone is against recycling.

perhaps costs in transport and distribution are higher? or the energy needed to dig that limestone out of the ground? but shouldn't that already be included in the numbers scody gave? wouldn't they have included those in the total energy savings? or perhaps we're really running out of room for landfills (i assume that's more a case of nimbyism)?
posted by not sure this is a good idea at 6:26 PM on August 11, 2008

ps of course, burning paper makes absolutely no sense. recycling is clearly better than that.
posted by not sure this is a good idea at 6:29 PM on August 11, 2008

Making paper is a very polluting process, more so than the recycling of paper

Actually, it's the same thing. Paper recycling means breaking existing paper down to pulp form, which then becomes the stock that makes new paper.

By the way, I worked in paper mills for about 15 years and some grades of paper we made had faux dirt added to the pulp, simply to make the recycled paper look more recycled.
posted by davebush at 6:29 PM on August 11, 2008 [4 favorites]

I think the links cowbellemoo provides answer your question. Briefly, the process is tree-to-pulp-to-paper. By recycle paper, you save the first step, which is energy intensive, uses lots of fresh water, and apparently chemically polluting as well. You don't usually see the tree-to-pulp plants because these typically locate near tree and water sources. They are big and dirty and hidden away in sparsely populated area.

Recycle, in general, is saving energy by doing things smarter. It takes energy to purify and turn one thing to another. Tree isn't a pure source of pulp (which is cellulose), so it takes a lot of energy, pure water and pure chemicals to turn tree to pulp. Once you have that pulp, turning it to paper is a less energy-intensive process. Cleaning printed paper back to pulp take less energy also. If the printed paper is thrown away, we lost all that energy investment and have to start from scratch again. Of course, I overlook the energy it takes to grow a tree in the first place, if we want to have a renewable pulp source.
posted by curiousZ at 6:29 PM on August 11, 2008

there's also the social aspect, of course. even if it doesn't do much good, recycling helps avoids the political costs of finding new landfills while making politicians look "caring and responsible". CO2 in the atmosphere is a "big problem we can't see or fix" while "dirty dumps" is something that voters see and worry about. and if people think they're doing something positive by recycling they're really not going to want to question that. so there's quite a socio-political snowball.

on preview: curiousZ - the question is "what problem we are trying to solve?". if it's minimising energy use then fine - recycle. but minimizing energy use is perhaps only good because it reduces global warming. in that case, recycling is bad because for every ton of paper recycled you get more CO2 in the atmosphere than you would have got if you had used trees instead (assuming it's buited and not burnt, and that trees are replaced).

now you can argue that those assumptions are poor - but in that case perhaps the emphasis should be on trying to solve those issues, rather than on recycling itself.
posted by not sure this is a good idea at 6:39 PM on August 11, 2008

But most recycled paper is still very white. Do they really have to bleach recycled paper as much as raw pulp?
posted by Foam Pants at 6:42 PM on August 11, 2008

Foam Pants, even if they did re-bleach recycled paper, that's not really much of an issue environmentally. Most paper is bleached using hydrogen peroxide, which though a fantastic oxidizing agent, and thus great bleach, is not much of a pollutant, as it breaks down very quickly if not contained.
posted by valkyryn at 6:56 PM on August 11, 2008

From what I've read, the only thing worth recycling is aluminum. Costs much less to recycle than extract. Still toss some glass and plastic in the bin though.

Possibly unrelated, but there's a made-for-TV movie called Manufactured Landscapes that focuses on China, the manufacturing, and all the waste we generate. It puts some things into perspective.
posted by hungrysquirrels at 7:33 PM on August 11, 2008

If it weren't true, we wouldn't be doing new logging for paper.

[citation needed]
posted by zsazsa at 7:37 PM on August 11, 2008

Your characterization of this as replacing a natural process with an industrial one is inaccurate. Making paper out of trees is a massively industrial process (and a nasty one, as anyone who has ever spent significant time in a paper mill town well knows) because trees aren't made of paper, they're made of wood, and wood is very solidly held together by a tough little organic glue called lignin, which you have to chemically get rid of before you can use all that cellulose to make paper with.

Paper, on the other hand, is made of paper and hence it's considerably easier to make into paper, although you can question the net energy issues at least within the confines of the plant because plants burn a lot of waste and lignin for energy when they're processing from timber. But putting aside energy gains from coproducts recycling is a energy saver as an intrinsic process, absolutely no question. It also reduces air emissions, saves a ton of water and uses less chemicals (generally requires less bleaching).

Paper recycling is increasing (in fact acceptable products to recycle have increased in many areas) because there is a market for the stuff. In general nobody is forcing anybody to use recycled paper as a feedstock. The era of easily available exploitable timber that doesn't require significant management to renew is pretty much over and the price of wood has gone up dramatically over the last decades. It is one of the pressures that has really hurt the magazine and newspaper industries, beyond the cultural shifts of the internet. Recycled paper stock is getting sold and turned into new paper because it is an economical proposition, and it's only going to get more so.

Penn and Teller's Bullshit pieces are hit and miss because they frequently don't have any expertise or special insight into their topics and they have ideological axes to grind that predispose them to certain interpretations. Their treatment of recycling was a piece of shit based on embarrassingly poor and incomplete research. Recycled paper is a vital component of the paper economy. It will take a long time but I suspect we will get to the point in this century where making paper from new wood can't be economically justified at all and it will all be recycled and alternative feedstocks.
posted by nanojath at 8:57 PM on August 11, 2008 [6 favorites]

I looked at a few government sites, states and provinces mostly, and, while there weren't any actual percentages shown, the overall impression I got was that most paper is still bleached and, to some degree, processed with chlorine compounds. There were a number of sites devoted to urging people to use chlorine-free paper and tips on how to find it. If most pulp was bleached with hydrogen peroxide, why would it be so hard to find?

Another thing that turned up in all that reading was the amount of the tree that is discarded when going from tree to usable pulp. A page from California quoted the percentage of waste at 50% of the tree. Now, reading something else on the processing of recycled paper said that the main waste problem of recycling paper was fiber lost in the manufacturing process but sounded like a minimal amount. So, if 100 lbs of tree ends up as 50 lbs of paper and 50 lbs of waste and is then is recycled into 40 lbs of paper and 10 lbs of waste, you have less waste than starting fresh both times.

I suppose with narrow % like this, you could make an argument against all the trouble but it still sounds like a good thing to me.
posted by Foam Pants at 9:54 PM on August 11, 2008

Industrial forestry is not a pretty process and it surely isn't natural. It takes quite a bit of energy to harvest the trees, process them, haul them (often a very long way) to the mill, chip them, and pulp them. Harvesting also causes significant direct environmental damage. Our forests are not an infinite resource from which we can take as much as we want with no consequences.

not sure this is a good idea: How much energy do you think is embodied in the following?
17 trees (which must be harvested, processed, hauled, chipped, and pulped)
275 pounds of sulphur (usually a petroproduct)
350 lbs of limestone (which must be quarried, crushed, and transported)
9,000 lbs of steam (you need to burn a lot of something, usually wood, to make this)

I can assure you that it is quite a bit more than just 225kwh (the steam alone takes more energy than that).
posted by ssg at 10:38 PM on August 11, 2008

It is worth recycling anything? Put all the energy-savings issues aside for a minute. Make your own personal landfill on your property by fencing off a big area. No property? Use a sidewalk or alleyway. Be sure to dig around and bury your trash as it builds up.

Every time you empty the trash, put it in your personal landfill. Do this for five years or ten years and then dig around. How much of your waste is just plain gone? How big is your pile?

Recycling is about being responsible in a way that isn't obvious. If the landfill were right in your face every day, you'd be motivated to keep that pile as small as possible by recycling anything you could. Recycling would be a completely self-rewarding act because it would get your refuse out of your face and into someone else's face. Your landfill stays small and might not grow too large too quickly. You'd buy products that generated less waste simply to reduce your own personal eyesore.

But with all landfills far away and out of sight, it's easy to forget what you are responsible for and what you can do to make things much, much better. Screw energy savings - what reduces your personal landfill should be your motivation.

Try keeping all your trash with you for just a few months and then ask why recycling paper and everything else is smart.
posted by loosemouth at 3:17 AM on August 12, 2008 [1 favorite]

"the only thing worth recycling is aluminum"

Googling this expression seems to mainly turn up people who are citing the Penn and Teller recycling show as their authority so it has clearly been influential. TV show producers are not too great at citing their sources - but in this case a 1989 paper called "Eight Great Myths of Recycling" (pdf) appeared to be a key source. You might find this refutation of the sources used in the program useful however.

It looks like some of the movement towards recycling was kicked off by wishful thinking and political expediency back in the 70s. That should not be taken to mean that the practices continue to fail to hold water today.
posted by rongorongo at 3:21 AM on August 12, 2008

Hang on... since when aren't forests a finite resource?

Yes, the huge thousand year old forests aren't going to reappear in a hurry but isn't paper just as successfully made from the farmed/managed forests where one harvested is replaced by one planted?

When you plant a tree it (hopefully) grows and sucks carbon dioxide out of the air.

Can we compare the net loss/gain of carbon in growing, transporting and processing and then burying to the loss/gain of transporting and reprocessing? It seems like a rather more relevant comparison...
posted by twine42 at 3:23 AM on August 12, 2008

It is worth recycling anything? Put all the energy-savings issues aside for a minute. Make your own personal landfill on your property by fencing off a big area. No property? Use a sidewalk or alleyway. Be sure to dig around and bury your trash as it builds up.

Every time you empty the trash, put it in your personal landfill. Do this for five years or ten years and then dig around. How much of your waste is just plain gone? How big is your pile?

This is one of the things that prompted my question. Isn't paper compost-able, just like coffee grounds? Wouldn't it be more responsible to ask people to compost their paper, rather than waiting for the big truck to pull up and haul it away?
posted by jbickers at 3:49 AM on August 12, 2008

Isn't paper compost-able, just like coffee grounds? Wouldn't it be more responsible to ask people to compost their paper, rather than waiting for the big truck to pull up and haul it away?

From what I understand about composting -- it's a fairly carefully-controlled process, where it doesn't work if you put too much or too little of one of the elements in.

And as for paper, I don't know about you, but the junk mail I get ALONE would overwhelm a compost pile pretty quickly (and that is WITH my already having contacted all the "stop junk mail" services and the like). We just have too much paper to deal with.
posted by EmpressCallipygos at 4:45 AM on August 12, 2008

davebush writes "Actually, it's the same thing. Paper recycling means breaking existing paper down to pulp form, which then becomes the stock that makes new paper. "

Not quite, trees are made of wood which if further removed from paper than paper is.

hungrysquirrels writes "From what I've read, the only thing worth recycling is aluminum. Costs much less to recycle than extract. Still toss some glass and plastic in the bin though. "

Most if not all metals are worth recycling. Steel being the poster child along with lead and copper.
posted by Mitheral at 5:56 AM on August 12, 2008

Isn't paper compost-able, just like coffee grounds? Wouldn't it be more responsible to ask people to compost their paper, rather than waiting for the big truck to pull up and haul it away?

Whilst paper is compost-able somebody making compost on any reasonable scale needs to get recipe right (like this) in order to get the required chemical balance of carbon, nitrogen and oxygen for the process to work and to end up with something that will really help plants to grow. If were to try composting my considerable output of paper waste at home I would suddenly need to add large quantities of other ingredients to make the mixture work; a commercial operator would face the same problem. Finally note that the composting process itself releases C02.
posted by rongorongo at 6:22 AM on August 12, 2008

Wouldn't it be more responsible to ask people to compost their paper, rather than waiting for the big truck to pull up and haul it away?

Several things: a significant portion of the paper waste stream that is recyclable composts poorly, depending on its treatment and composition. Further, asking people to start composting is a significantly different proposition than asking them to recycle. Pretty much anyone in any situation can participate in curbside recycling. The same is not true of composting. Relatively few people compost even the easy stuff, vegetable and lawn waste and so forth. I do, and I certainly would not want to add paper to the mix. If you stopped recycling paper most of it would end up in the landfill or incinerated, as it did before recycling.

And again, the industrial production of paper from trees is neither a natural nor benign process, so you're not just talking about one commercial transportation and industrial production process, you're talking about comparing two different processes. They have to send big trucks around to pick up the trees, you know, as well as all the logging machinery, chain saws, etc.

And paper isn't the only things the trucks are picking up. Once you've created a collection system, even if aluminum, say, is the clear winner from a cost, energy and environmental perspective, why not collect multiple products at that point?
posted by nanojath at 11:23 AM on August 12, 2008