Le recycling debate

[applepie]

Penn and Teller: Bullshit! Recycling - Google Video

note fairly long video and bits of it are totally irrelevant.

I had been having discussions with my friend about recycling materials etc and she sent me this.

errr....to be honest, some parts of it was interesting, but it really avoided alot of key questions. not having to deal with extraction (with is assocaited destruction and env. impacts)

not convinced about the landfill part either, we worked on designing some of the things they discussed but back then (almost a decade now i guess?) it was not feasible (economically) to extract useful methane gas. then again technology goes in leaps and bounds. plus its difficult to build long term structures on it depending on the amount and type of waste underneath.

however, i do agree to a certain extent regarding the recycling of certain plastics, nor does it touch on the recyclying of potentially hazardous wastes (pesticides, herbicides, etc)

personally, I had no idea that such a poorly presented program is actually quite popular in the states. very brash and idiotic speech and presentation style.

but does raze some interesting questions, which are similar to my view thoughts regarding occasionally misguided environmental concern.

[Dangerous Dan]

I didnt have to time to watch the video as im doing some work (well obviously not at this minute, but I do have a pen tucked behind my ear to trick myself into thinking I am), Anyway regarding the methan extraction I know there is a project running in Newton Abbott where it is converted into electricity. I am currently involved in a project at Uni and we are designing a sustainable sports centre on/near a landfill site and we are looking at powering it through methane extraction - that much free energy makes sense.

Dan

[David M]

you can use the methane gas for electricity generation useing modified deisel engines to drive genarators

landfill gas

[applepie]

cheers,

back then it was possible but without subsidies, it was not economically viable in comparison to simply burning it in a flare stack which is still widely done.

gas collection as well had a considerable wear and tear on the pipes used, which not major but did require more maintenance than thought.

furthermore, gas extraction also led to the contamination of air which major downside was slowing down the anaerobic bacteria (due to oxygen) in the landfill site. in short the landfill site had to be deep and big enough.

plus the studies back then were flawed, the emissions estimations were too high (sometimes 3 - 5 times higher than actual!!). the estimates were used in the design phase, wasnt until the americans had done proper studies did corrected values arrived. (well I am assuming industry are using them)

therefore, secondary pollution control systems had to be designed which put the costs quite high.

I do not know the current capital costs of setting up a LFGE now (probably plummetting down now with micro-turbines etc), but I would still guess that it is not viable without subsidies for smaller landfill sites.

plus i would also guess, that the actual cost per unit of electricity generated via landfill gas is slightly higher than that from natural gas. however, this does not take into account the possible/alleged lower emissions. and theres the law that says X% has to come from renewables and are guaranteed a minimum price anyway.

I am pretty sure they solved all the technical problems for large landfill sites (which were quite easy IMO) but not sure about smaller landfills.

[Richard Mason]

The last two Councils I worked at here in Tas extract landfill gas and put it through a generator; I'm pretty sure it's an internal combustion enineer rather than a turbine. The power is sold to Aurora, the local electricity supplier. It's competitive as our power generation in Tasmania is 90% Hydro, which is quite expensive, compared with the coal fired plants on the mainland where they mine coal in opencuts, in seams 30M thick, and drop it on a conveyor straight to the furnace.

The last of those Councils achieved a 90% reduction in its corporate greenhouse emissions by converting methane to CO2, methane being 20x stronger as a greenhouse gas, than CO2.

As for municipal waste recycling, I'm involved in this day to day, we have a separate collection of glass, plastics, metals, paper/cardboard and I can tell you that in this part of the world, it just doesn't stack up. It costs 30% more to run the service than what we get for the recovered materials.

Personally,. I don't believe that this is sustainable; after all, in this day and age money can be considered an equivalent to energy; if it takes more energy to recycle the stuff than it does to mine the raw materials, manufacture and transport the materials, what's the point. Sure, there's the issue of landfill space, but it will still be cheaper for us to bury the stuff.

In Europe, North America and Asaia, which have awesome landfills, I think it's possible that at some piont in the future, it ,maybe possible that they could be mined; after all the garbage isn't going anywhere and much of the higher value stuff will still be there in hundreds of years, conveniently close to centres of population and energy generation/transmission/transport links etc.

An analogy for this is gold production. I used to live in Ballarat (Victoria) which was the scene of one of histories biggest gold rushes, back in the 1850s. Initially, the miners concentrated on alluvial gold, before tracing it back to it's point of origin and mining it from gold reefs, deep underground. Once this easily gold was worked out, mining virtually died out.

The gold processors have realised in recent years, that the gold missed by the old timers is still present in mullock, the huge layer of mine waste which blankets most of the city. The old extraction techniques were quite primitive and in some areas, this mullock contains higher gold concentrations than some of the ore bodies being worked in other parts of the world.

[applepie]

does that incl. the recycling of paper?

I was under the impression that recycling paper is generally much more energy and resource efficient. espeically with office paper and cardboard.

the use of fast growing trees puts an additional environmental strain on the land. this is often not taken into account since its long term and hard to quantify.

same goes for aluminium, which also reduces the high electricity cost of Al extraction from ore without having to have a massive mine etc. however, the current recyclying process is rather inefficient IMO where a significant percentage of it is landfilled and the cost of energy is higher than it should/could be.

i agree with plastics, where most of the times its just not cost effective. and the use of the recycled material is generally unsuited in comparison to virgin material, if i recall only around 10% can be mixed into virgin material to make plastic new bottles. usually just grinded into shreds.

however, it also depends on economies of scale, the more percentage recycled, the costs per unit recycling should go down in theory (with the exception of certain items).