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20 December 2009
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All waste will have to be managed correctly.
Although this slide illustrates how household waste is managed in a
non-EU country, the photographs could have been taken in Germany, Sweden
or most other EU countries. They were taken in Romanel-sur-Lausanne, a
village where I used to live, with a population of about 3,000 souls.
The waste "stockade" is only one of three or four similar, in strategic
spots around the village. The way this worked is that householders were
expected to sort out their rubbish. Twice a week, there was a
door-to-door collection of household waste (scrap food and anything that
was un-recyclable). In some Communes, this had to be placed in special
bags with a printed vignette, as a means of perceiving the collection
tax; this encouraged householders to minimise their waste because the
more bags you fill, the more it costs. Once every three months, there
was a collection of bulky objects (furniture, bicycles, non-electrical
appliances etc.), a separate collection of electrical appliances, except
refrigerators and freezers. The last-named were collected regularly, on
demand, but they had a special tax imposed on them, for destruction
without liberating any ozone-depleting chemicals. All the recyclable
material was taken to the "stockade", by the householders. The last
image shows the village "voirie", where hazardous materials could
be taken to be disposed of. Not shown is a composting site, where garden
refuse could be taken, to produce a fine compost for the villagers' use.
This may seem a costly exercise, but the village authorities actually
sold all the recyclable waste, which paid for all the costs involved in
maintaining the stockades, collecting the filled bins (about once per
week) and so on (you can see that the ground of the "stockade" is paved
and kept clean).
Incidentally, the twice-weekly household refuse collection goes
straight to a special incinerator which serves the whole of the Lausanne
region (about 150,000 population), the heat from which is used to
generate about 10 per cent of the region's electricity requirements and
to provide heating and hot water to a large University hospital complex.
(See essay on
Renewable Energy.) This is also a paying proposition and, above all,
it reduces the landfill volume by about 90 percent. Scrap wood is also
sent to the incinerator, whether it be from forest management, building
and demolition sites or broken furniture from the quarterly bulky
objects collection.
Many landfills are a total disgrace and do not conform to
regulations. There is often no control of the way they are managed or
the waste that goes into them. EU regulations are very strict in that
they have to be constructed in a manner that can be safely capped and
with separate landfills for hazardous, non-hazardous (domestic) and
inert wastes. However, the volume of landfilled waste must be reduced
progressively to 35 per cent of the current levels over a number of
years. This implies maximum recycling and incineration. Greece was fined
€20,000 per day for about a year because of a single
non-compliant landfill on one of the islands, with both industrial
(hazardous) and domestic waste being deposited in the same landfill.
It is interesting that the UK taxes the use of landfills, over and
above operators' charges, at the rate of £15/tonne (figure valid from 1
April 2004). This must surely be a good incentive to minimise landfill
use. On the other hand, it may incite illicit dumping elsewhere, which
is dangerous.
The easiest way of reducing the volume of waste is by recycling as
much as possible. One polypropylene bag given to you in a supermarket
may weigh only 5 g, but if you count the millions that are consumed
every week, the annual tonnage is large. This could be cut down
significantly without any inconvenience to the consumer. The first
action is to motivate consumers to empty them carefully and then sort
them into reusable (clean, untorn) ones and others, which can be used
for waste paper basket liners or similar or, if they are totally
unusable, placed in a pile for sending to a recycling bin. A few only,
dirty ones, may end up in the dustbin. The next time you go shopping,
take your good ones with you and use them, instead of new ones; each bag
should, on an average, be good for three to four trips to the
supermarket. The supermarkets themselves can make new ones available
only on request; better still, they can charge, say, 5 cents each for
them as an incentive towards recycling. If they make them tougher, so
that they can make at least a dozen journeys, it would be worthwhile to
charge more, say 15 cents. An even better alternative would be to have
empty cartons (also reusable) available: this is common practice in
Europe and avoids the need for bags altogether. One UK supermarket chain
sold robust plastic boxes (I think for £5) which were estimated to be
good for several hundred trips. They fitted into the trolley, so that
the purchases could be placed straight in them at the check-out, and
made packing the boot of the car almost instantaneous (and faster
check-outs). This is just one simple way that everyone can do, with no
inconvenience.
Recycling plastics is a problem because there are so many different
types which should not be mixed. Many items have a two to four letter
code adjacent to a recyclable sign, indicating the type of plastic it is
(non-exhaustive list):
|
Symbol
|
No. |
|
Plastic (trade names in
italics)
|
|
PE
|
7 |
|
Polyethylene, Polythene
|
|
HDPE
|
2 |
|
High-density polyethylene
|
|
LDPE
|
4 |
|
Low-density polyethylene
|
|
PVC
|
3 |
|
Polyvinyl chloride
|
|
PP
|
5 |
|
Polypropylene
|
|
PS
|
6 |
|
Polystyrene
|
|
PET
|
1 |
|
Polyethylene teraphthalate Terylene
|
|
PC
|
7 |
|
Polycarbonate Makrolon
|
|
PMMA
|
7 |
|
Polymethyl methylacrylate Perspex, Plexiglass
|
|
PTFE
|
7 |
|
Polytetrafluoroethylene Teflon,
Fluon
|
Wherever possible, the ideal would be to keep each type of plastic
separate.
PET drinks and mineral water bottles are a special case. They cannot
be reused for hygienic reasons. The caps and rings should be discarded
with PVC, PP or PE, according to their markings and the bottle flattened
as far as is possible. They can then be chopped up and melted for making
clothing fibres, ropes and other quality items. Unfortunately, the
supply exceeds the demand so, inevitably, the remainder are preferably
incinerated. However, a Japanese company has recently announced that
they have found a way of breaking the plastic down, back into its
original chemical components, meaning that new bottles can safely be
made from old. It is too early to say whether this process will be
viable.
In some European countries, a cash deposit is placed on bottles, to
ensure they are returned, rather than simply thrown away.
Aluminium (or aluminum for our Transatlantic friends) is the most
profitable material for recycling, whether from drinks cans, foil, pie
cases, machining swarf etc. Extraordinarily, scrap aluminium is even
quoted on the London Metal Exchange. Why should this be? Mainly because
the electrolytic smelting of aluminium from ore requires massive
quantities of energy, whereas the remelting of scrap requires only a few
percent of it. There is no excuse to throw away even dirty or painted
aluminium, as organic material is gasified in a pre-heating phase and
the gas is used to perform the same preheating!
Just think of the tons of newspapers (and bureaucratic
paperasserie issued by governments!) that are read once and then
thrown away, not to mention cardboard used for packing. This is all
recyclable. In fact, there is a mandatory obligation to recycle up to 45
percent of all packing materials (non-paper, as well as paper) under EU
directives. Why should this valuable material be simply thrown away and
lost for ever in a landfill (probably emitting methane into the
bargain).
This is defined as any waste material that could damage the
environment. This includes products like used hydrocarbons, car
batteries, dry batteries, accumulators, paint, all chemicals, heavy
metals, solvents and many others. The handling of hazardous waste
requires skill in identifying the nature of the product and the safe
disposal. Let us take a car battery as a typical example. To start with,
lead is a highly toxic metal and all lead compounds must never be
allowed to enter into nature. Apart from the obvious immediate danger,
there is also a (very small) risk of underground drinking water sources
being contaminated. The outer case is usually some form of plastic and
it can be recycled after emptying and cleaning. The liquid inside is
dilute sulfuric acid with some solubilised lead sulfate. This has to be
neutralised with caustic soda: a small (harmless) excess of soda to a pH
of 7.5 will cause all the lead salts to precipitate as lead hydroxide
and they can be filtered out and recycled. If the sodium sulfate
solution is acceptable for disposal, as is, then this can be done,
otherwise it will have to be concentrated by an ion exchange mechanism
or in evaporation beds, drummed and landfilled in a licensed site for
chemicals. There will be solid sediments at the bottom of the battery,
consisting mainly of lead salts and oxides and particles of flaked-off
lead. These have to be recovered. The plates consist of a lead framework
with lead oxide paste inserts. The metallic lead can be recovered for
recycling by melting it and the oxides skimmed off. All the lead salts
and oxides from these processes form an extremely rich lead ore that can
be smelted into metallic lead for re-use. The dross from this process
must be skimmed, drummed and landfilled, still as hazardous waste.
Finally, the separators, a porous plastic, can be incinerated in a
suitable installation which will recover the sequestered lead in the
ash. It is obvious that these processes cannot be done by just anybody,
and an expensive infrastructure is required. This includes the licensed
landfill, which must be totally sealed in a lined concrete structure
with extensive waste water treatment for all the run-off. On no account
should rain water falling on the landfill be permitted to escape into
the ground. Similar restrictions apply to all other hazardous waste. If
it is combustible, it should be used as a fuel additive in appropriate
installations, such as cement kilns equipped with flue gas scrubbers and
precipitators (never in installations without these).
This is a special consideration and I have devoted a whole
essay on
this problem.
This is a particular case, because all old refrigerators, freezers,
chillers and air-conditioners contain CFCs (ozone-depleting
gases) in the cold circuit and in the foam insulation. More modern
ones may contain HCFCs (also ozone-depleting) or HFCs (greenhouse
gases). They are therefore all polluting if not recycled correctly.
International regulations are very strict on this matter: it is illegal
to dispose of this equipment except through a means whereby the
polluting gases can be fully recovered for recycling or destruction.
This is usually done by placing the item in a crusher which is fully
enclosed in a gas-tight compartment, so that all the gas can be
withdrawn and collected from both the compressor circuit and the foam
insulation. Perhaps better, another way is to cut the pipework with a
special tool with a gas-tight surround to extract the gas, then
dismantle the foam, which is then pulverised in a vacuum container to
extract the gas from it. This method has the advantage of easier
recycling of all the parts at a lower capital cost, but does require
more labour.
Some countries charge a recycling tax on all cold equipment, as it
costs a typical €50 (USD 60) to correctly recycle a household fridge.
Some countries have had problems providing a sufficient number of
qualified recycling facilities for refrigeration equipment. In the UK,
for example, there is a mountainous backlog of equipment awaiting
destruction. One
report has stated that illicit destruction has taken place by
throwing many old fridges over a bridge into the Clyde, in Glasgow,
certainly easier and cheaper than legal recycling, but not good for the
ozone layer. However, it is believed that this case may have been a
criminal scam.
It is illegal to ship refrigeration equipment containing CFCs to
other countries.
The EU has strict directives in force governing the disposal of cars
and other road vehicles. All fluids, batteries, tyres and sources of
heavy metals must be removed before recycling the metal. Of course, the
removed materials must also be recycled or destroyed correctly. This has
yet to be implemented in Cyprus.
Many countries have a long and painful way, both for the country and
the individual, before they can pretend to even approach the standards
that are in force in the EU and other Western countries. It will require
a radical change of mindset before many persons realise that waste is a
serious matter.
Waste News
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