Your Questions About Recycling

The Expert answers:

What is the question?

The Expert answers:

You’ve got a point – in future I’ll just leave it out in the rain!

The Expert answers:

It’s not reused. Most wastewater that goes to a wastewater treatment plant does not get pumped back into your house as fresh water. In fact, in the US, almost nowhere is this the case. Wastewater simply doesn’t get treated to high enough standards for that to be possible.

Water that comes into your home likely came from an aquifer or from a surface water source. Both of these do indeed recharge naturally, but if you are pulling water out of them faster than it can be replenished, then you could be setting yourself up for a very big problem. The total amount of water on earth does not change, but if a city of say 200,000 people gets their water from only one aquifer, and suddenly that aquifer runs dry, then you will have a public health disaster as all of these people suddenly no longer have running water.

Granted, this is an extreme scenario and has never actually happened. When a water source runs low, cities need to spend huge amounts of money and effort in securing an alternative source, and developing nations may not even have the resources for that. Fresh clean water is not an infinite resource in many places.

The Expert answers:

I’ve read both, and I am confused! I stopped rinsing years ago (though I don’t eat anything quite as odorous as cat food, so it’s less of a kitchen smell issue) after reading that this was not necessary for recycling, but I recently read the opposite, and now I’m not sure what to do. I think the best thing to do is to call your local public works office (or whoever runs your recycling program) and ask what they want.

If they do want rinsing (or if you just don’t want the smell of cat food), you could start collecting grey water in your house. Here is some information about that:

http://greywateraction.org/greywater-recycling

Basically, greywater is water that you wouldn’t drink but isn’t totally gross. I can’t see anything wrong, for example, with putting a bucket underneath the hose that brings rinse water out of your washing machine and using that water to rinse cans for recycling.

Thanks for giving me something to think about. By thinking about your problem, I now have an idea for myself, too.

The Expert answers:

In our University, we treat the waste water to recycle and use it again. This is true in many of our universities, like Rajagiri, St. John’s, etc.

The water is collected in a large tank and filtered and treated for reuse for washing and garden.

The steps for sewage treatment include separating the solid waste and burying it in large fields, so that the heat of decomposition destroys the common germs and organisms and the waste slowly decomposes, and later it is used for manure.

Many cities in India let the wastes flow out into the sea, but this has made the sea water full of black decaying matter and the beaches have become very dirty for the past two decades.

The Expert answers:

On Earth you can get away with “throwing stuff away” for a very long time, just because Earth is so big. But the more people there are per square meter, the more of a problem fouling the nest becomes. In space, on a tiny spaceship, it can be a catastrophe. You have two issues, water and everything else. You want the water and the rest of the waste as separated as possible, and you want as little loss and as much utility as possible. So you need to recycle, relentlessly.

The human body is an open system. Food comes in, waste goes out. One of the primary jobs of the lower G-I tract is to extract as much water as possible from the waste before it is ejected. Otherwise we’d dehydrate a lot faster. But such a system means we need a constant supply source. Fortunately, we live on Earth.

Earth is a closed system, but a very big one. Concentrated waste is shipped somewhere that it can become diluted by natural water and reprocessed by microorganisms, who can’t really tell it from dirt. Eventually the minerals reenter the food chain as fertilizer. Animal waste has been used as fertilizer for millennia. We don’t use human waste because of the possibility of spreading human diseases, but with proper sterilization, it would be safe.

A spaceship is a very small, closed system. Everything you dump overboard is no longer available for use. If you’re only staying for a week or you expect a supply ship to come by soon, it’s not a problem because your system isn’t closed. But if you are on a long haul voyage, everything counts. The water you drink will eventually end up being the water you drink again because the alternative is running out of water. So whatever combination of filters and treatments is necessary to make it happen will be there. Most Earthbound sewage treatment systems don’t do “Tertiary Treatment” because it’s expensive, but necessity is a great motivator. (And even secondary treatment produces what the industry calls “sludge”, which has to be disposed of and often ends up in remote forests where it can fertilize safely away from people.)

But some water is left in the waste because micro-organisms need it too. They break down the waste even further, separating toxins and nutrients, making it fit to grow plants in. We have a long, long way to go in developing this science for long space voyages but it is clearly possible.

This all seems distasteful to contemplate because we are not used to seeing such a compact re-use cycle. But the cycle has to be small enough and efficient enough to fit into the system or the system won’t work. A lot of planning and ingenuity will need to go into designing a long term, self-contained space system. Decisions about safety, efficiency and practicality have to be made. (The astronauts may have to go vegetarian because meat production is very inefficient.) And there are other issues, like recycling carbon dioxide back into free oxygen. (Closed system, remember?) So, even though we don’t quite have the technology to practically do all this, we have a general idea of what needs to be done. And necessity, as always, will drive invention, whether in the tiny closed system of a spaceship, or a big one like Earth.

The Expert answers:

Recycling is the reprocessing of materials into new products. Recycling prevents useful material resources being wasted, reduces the consumption of raw materials and reduces energy usage, and hence greenhouse gas emissions, compared to virgin production.[1] Recycling is a key concept of modern waste management and is the third component of the waste hierarchy.

Recyclable materials, also called “recyclables” or “recyclates”, may originate from a wide range of sources including the home and industry. They include glass, paper, aluminium, asphalt, iron, textiles and plastics. Biodegradable waste, such as food waste or garden waste, is also recyclable with the assistance of microorganisms through composting or anaerobic digestion.

Recyclates need to be sorted and separated into material types. Contamination of the recylates with other materials must be prevented to increase the recyclates value and facilitate easier reprocessing for the ultimate recycling facility. This sorting can be performed either by the producer of the waste or within semi or fully-automated materials recovery facilities.

There are two common household methods of helping increase recycling. Firstly kerbside collection (US: curbside collection) is where consumers leave presorted materials for recycling at the front of their property, typically in boxes or sacks to be collected by a recycling vehicle. Alternatively, with a “bring system”, the householder may take the materials to recycling banks or civic amenity centres where recyclates are placed into recycling bins based on the type of material.

Recycling does not include reuse where items retain their existing form for other purposes without the need for reprocessing.

Benefits-

One of the main benefits of recycling comes from reducing the amount of new material required. In theory, recycling allows a material to be continually reused for the same purpose, and in many cases this theory holds true, most notably in the recycling of metals and glass.

Since less raw material is required, recycling creates further benefits for materials where cost of the initial extraction or production is high—either economically, socially or environmentally. The recycling of aluminium, for example, saves 95% of the CO2 emissions—an environmentally harmful greenhouse gas—compared to refining new metal.

Concerns about limited resources such as raw materials and land space for disposal of waste have increased the importance of recycling. However maximum environmental benefit is gained by reducing the amount of waste produced, and reusing items in their current form, for example refilling bottles. All recycling techniques consume energy, for transportation and processing, and some also use considerable amounts of water. Both of these resources have an environmental impact which is why campaigners use the slogan “Reduce, Reuse, Recycle” to indicate the preferred order for waste management in the waste hierarchy.

Drawbacks-

There may also be drawbacks with the collection methods associated with recycling. Increasing collections of separated wastes adds to vehicle movements and the production of carbon dioxide. This may be negated however by centralized facilities such as some advanced material recovery facilities of mechanical biological treatment systems for the separation of mixed wastes.

Perverse consequences from mercury recycling have been cited recently by the Wall Street Journal (April 20, 2006). The article traces mercury recovered from USA recycling programs into sales of mercury for alluvial mining activities in Brazil. During the autumn of 2006, the EU banned the export of liquid mercury (Europe has no mercury mining, only recovery from recycling). A full life cycle analysis prior to institution of recycling programs may reduce the risk of unintended environmental consequences..

The Expert answers:

Some of the attempts TOO recycle water may impair the environment- law of unintended consequences when one looks at the Orange County plan. Not everything can be removed from the waste water- and to pump an aquifir full of pharmeceutical residue is just asking for trouble.

When Waste news covered this about 2 years ago, they did not hide the fact in the publication that there may be problems. Http://www.wastenews.com

The real issue is water can be recycled- how much are you willing to pay for it right now? Many areas are already using desalinization systems to remove salt from brackish water sources, but it is not cheap. Similar technology would be used with other less than perfect water sources. .

The Expert answers:

Most tertiary wastewater treatment facilities can get wastewater down to drinking water standards. The big problem is that the pharmaceuticals people take (birth control meds, epilepsy meds, ritalin, etc.) goes through this process and show up in the finished product. These residual medicines are generally not tested.

California was one of the first states to try this – injecting treated wastwater back into the aquifer above southern california communities. Check out the story of “Water Factory 21”.

In summary, wastewater can be treated to drinking water standards, if the facility tests for all the necessary constituents that might cause human health problems. The bacteria and virus, etc. Can be removed easily as well as most metals. It is the anthropogenic (man made) chemicals that get flushed down the drain that is the big question.