Building on the success of Build-a-Bear (god knows how), I bring you the Build-a-Bag.
HDPE, and for that matter, LDPE, have been overlooked in the world of sustainablility. Now don't let the raw ingredients (oil or petroleum, in fact it takes almost two kilograms of petroleum to make one kilogram of HDPE) throw you off the trail. These magnificent beasts of burden can, over time, deliver more energy per kg than petrol. How? By being containment chambers for far more energetic processes. Energy density? Yeh, baby. Yeh!
They are, at least at atmospheric pressures and temperatures, chemicaly inert, unless you plan to introduce industrial solvents and strong oxidisors. Add to that very low porousity (for HDPE anyway) and you have yourself a veritable "elephant stomach", or "diet coke and menthos rocket". The principle is the same. Order now and get a very energy efficient Ultrasonic welder.
The point being, at low cost, these *stomachs* are widely available, even as a sequence of mutilated 2lt PET coke bottles, as containment chambers for beneficial reactions. Chemically unreactive, designed for pressures well above atmospheric, these form the basis of the Build-a-Bag model. Take free assembly instructions, add bacteria(waste) from apex herbivore, add acids (probably from a slain beasts stomach), leave in the sun, add water (or sugars and more acids), syphon of excess hydrocarbons (methane) for fuel, use waste as fertiliser. Feed crops to family, or market, or directly back into the "bio-reactor".
Added benefit, when the "factory" has reached its past sell by date, it has sequestered the hydrocarbons of 1.75 kgs of petrochemical it took to produce 1kg.-- 4whom, Sep 29 2008 huh?-- Voice, Sep 30 2008 Is 4whom related to Treon?-- Canuck, Sep 30 2008 what [Voice] said but more "?"s [edit] I've read it a few times and.... you want to make eco-recycling-demo kits for schoolkids out of old 2L soda bottles? cow patties sold separately I assume.-- FlyingToaster, Sep 30 2008 "Recycle old plastic bottles into biogas reactors"-- neelandan, Sep 30 2008 A few points of order:
The idea is to create bio-reactors from waste HDPE and LDPE.
The Build-a Bear reference is to the stores where you custom make your own bear from shop parts provided. They charge an enormous premium for a product from which "labour" has been subtracted. By providing the IC/IP, a place, and the inventory items, and subtracting final assembly they have created a business model cuts down on logistics and energy costs (well not really, but it could be)
It is not for school kids (although that is fantastic) but rather an "elephant (or other herbivore) stomach" in every village in remote rural areas. The advantage of owning just the stomach, is the reduced cost of locomotion and zero energy wasted to reproductive efforts. This energy will be recouped as gas, the reminants (almost said ruminants) to be used as fertiliser, for crops.
I used 2lt coke bottles as an example, but 5lt, 20lt, 100lt (and even 1000lt) HDPE containers would probably be more available and useful. In fact, in these countries bottling is still in glass, for which you pay and recieve back a deposit.
So you take waste plastic, create stomachs defined by the environment for that environment, if necessary use more than one chamber, all to a "recipe" supplied by Build-a-Bag. Final assembly takes place at the location of the goods or the village.
Not perfect, not earth shattering, but there.-- 4whom, Oct 01 2008 there is a there there? Is there a there in the house? Can i get a there up in here? Please elaborate on where we may find the there, in particular where the bear there or the bag there may be located relative to other theres bears and wheres.-- WcW, Oct 01 2008 Better. Now: What is a bio-reactor, and how does it work? What is a "bear", presuming that is not a quadroped that eats people? What is HDPE? What is LDPE? What kind of stomach can digest these materials? What does this have to do with bears? Whats IC and IP? Is there a real shop (brick and morter establishment) where one can build "bears"? What do elephants have to do with all of this? After HDPE and LDPE are digested, what remenents are you expecting? How does an environment define a stomach? How does an environment require a stomach?-- Voice, Oct 02 2008 [Voice], thank you for your continued patience.
A bio-reactor is a biomass reactor, or stomach. Breaking down biomass (usually plant material) into sugars, fats, water, gas, and cellulose fibres (usually containing trace elements of nitrogen (nitrates/nitites), carbon, sellenium, phosphates, etc.) Gas to be used as fuel, the rest as fertiliser.
HDPE and LDPE are High Density Polyethylene and Low Density Polyethylene, as well as the implied PET (Polyethylene Terephthalate). These form the stomach, or reaction chamber.
IC and IP are Intellectual Capital, Intellectual Property. These terms are usually interchangeable.
Yes, there is a real shop where you can "build" teddy bears, at a premium price.
Elephants follows on from [django]'s Elephant Dung Tracker. The suggestion here being instead of following animals around or modifying behaviour, just duplicate the stomach in your local area.
The HDPE and LDPE are not digested they are the stomach wall (or teddy bear to be stuffed). The contents to place in the biomass reactor are plants from the surrounding environment. This makes it locally specific. Different herbivores are more prevalent in the environments of their foodstuff (different stuffings for your bear). To make a catch all biomass reactor might not perform as well on leafy jungle foilage as on savannah grass. So use local materials to produce the insides of a stomach *suited* to your local environment.
So building a teddy bear (stomach) suited to you (your flora, supplied by you with your labour) by supplying only knowledge (IP) and basic (would have been waste) materials.
Zero points for brevity...-- 4whom, Oct 02 2008 Bun, but how are you going to make it cost effective? And this will be much more easily understood if you replace the word "bear" with "biomass reactor."-- Voice, Oct 02 2008 yeah, sorry, I don't see it as being particularly useful outside of kids' science class or DIY demos, mostly because it'd be more economical *and* bio-friendly to use a permanent (set of) container(s), and find a way to use the plastic as anaerobic biomass.-- FlyingToaster, Oct 02 2008 is it strange i would rather use an elephant's poo than my own, as fertiliser?-- williamsmatt, Oct 02 2008 not really, I'd rather use elephant's poo than yours as fertilizer, too.-- FlyingToaster, Oct 03 2008 You're far more likely to catch a human disease from human poo than elephant poo.-- BunsenHoneydew, Oct 05 2008 and with elephant poo you could probably train dung beetles to get it for you.-- FlyingToaster, Oct 05 2008 I was going to write a "Build-a-Bog" but outhouse tents are baked, apparently.-- Spacecoyote, Oct 06 2008 +-- danman, Apr 20 2009 Since this has been bumped, by the obviously well meaning [danman] (in some bizarre "quid pro quo" I assume). I feel obligated to re-iterate this point. Rural african villages have low penetration to *any* form of fuel. Whether fossil, electrical, solar, wind, etc. However, they drink cooldrink/beer/other from 2lt and 5lt PET bottles. These bottles and their "grown-up" brethren (200lt - 1000lt) have two characteristics which are important. In the absence of industrial solvents and high temperatures, HDPE, LDPE and PET are, for all intents and porpoises, inert, and can withstand pressures of several atmospheres. They can therefore act as stomachs (biomass re-action chambers), (in accordance with a Build-a-bag recipe) to produce methane (in fact any of the simple x-anes and residual waste). The gas, butane/propane/methane can be used as a fuel, and the waste as fertiliser. Don't look at the finger, or you will miss all the gastro-intestinal glory.-- 4whom, Apr 20 2009 Dan the man's a [4whom] fan.-- theleopard, Apr 21 2009 Have gas powered motor bikes that run on these bottles. Instead of a gas tank you have a couple of these bottles (full with methane) to run your bike on.-- pashute, Nov 15 2012 huh?-- popbottle, Jul 16 2014 " Is 4whom related to Treon? — Canuck, Sep 30 2008 "
What [Canuck] said...-- normzone, Jul 16 2014 random, halfbakery