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November 17, 2009

water problem in central asia : is there a solution?


With the arrival of summer, the problem
of water for irrigation is becomes increasingly urgent in the Central Asian
republics. With their considerable cultivated lands, Uzbekistan and Kazakhstan
are looking at a substantial water shortage this summer. By producing
electricity this past winter, Kyrgyzstan delivered considerable amounts of
water to Uzbekistan and Kazakhstan in non-irrigation season from its
reservoirs. That, in turn, results in a shortage of water in dry summer
months. As this problem affects the lives of millions of people, regional
cooperation is needed on the use of this scarce resource in the most rational
and mutually beneficial way.

In Soviet times, water posed no problem.
The upstream states, Kyrgyzstan and Tajikistan, were collecting water in
autumn and winter in large reservoirs and delivering it to Uzbekistan and
Kazakhstan in the irrigation period. Downstream states, in their turn,
provided upstream republics with coal, electricity and other energy resources.
Thus, for 68 billion cubic meters of water collected and delivered to
Uzbekistan and Kazakhstan during 1986-1991, Kyrgyzstan received large
quantities of coal, lubricants, and natural gas. By contrast, 78.125 billion
cubic meters of water were similarly released between 1992 and 1997, but the
downstream states were increasingly selling their resources on world market
prices. Without possessing rich natural resources and being in a hard economic
depression, Kyrgyzstan has not been able to pay for importing energy resources
on time

During energy crises these last few
winters, Kyrgyzstan has been using water for the production of electric
energy. But that does not allow water to be collected in reservoirs, and
consequently downstream states have less water for their irrigational needs.
Uzbekistan’s gas embargo in the winter of this year forced Kyrgyzstan to
release water from reservoirs in order to provide the population with energy.
This will obviously cause problems to the downstream states in the irrigation
of their lands. According to the KABAR news agency, Uzbekistan may lose about
$400 millions of revenues from the sale of cotton as a result of water deficit
this year. Kazakhstan’s losses also seem to be significant: the cultivation
of cotton and rice in the southern regions depends on water supply from
Kyrgyzstan and Tajikistan.

This situation requires an urgent
solution. The shortage of water may to some extent be explained by the
irrational use of this resource by population. Galima Bukharbaeva, IWPR's
regional director in Uzbekistan writes that according to Bioecology
specialists, 40% of the water was lost in irrigation system in
Karakalpakistan. In this light, rationalization of the use of water seems to
be the most logical step to take for the Central Asian governments. Interstate
management of water resources is also becoming one of the hottest issues in
relations between republics. The idea of demanding a price to be paid for the
water collected in reservoirs during winter is becoming more and more popular
in Kyrgyzstan. Proponents of this idea argue that downstream states should
compensate Kyrgyzstan’s shortage of energy caused by water collection in
winter months. Another point raised is that the large reservoirs, serving the
whole region, were built on arable land that could bring considerable revenue
for agriculture. But opponents argue that water is to be considered as a
common good, gifted by the God, which cannot be sold at all.

With the arrival of summer, agricultural
fields will soon demand water. It is doubtful whether Central Asian states
will be able to cooperate to arrive at a realistic way to provide them with
water for irrigation. The political implications of high-level negotiations is
also an open question.


November 16, 2009

Denmark: No Environmental Benefits in Collecting Disposable Plastic


A report by Denmark's environmental protection agency (EPA) concludes that there are no environmental benefits in collecting disposable plastic bottles and other plastic containers, and that the costs of recycling them are unacceptably high. The findings appear to confirm the results of similar studies in other European countries.

The German environment agency reported earlier this month that small lightweight packaging items might as well be incinerated as recycled on environmental grounds (ED 02/07/02). This spring Austria's environment agency released similar findings (ED 09/03/02).

According to the Danish EPA, even a "pared-down" collection system involving delivery to recycling centres and export for recycling - which would be cheaper than recycling in Denmark - would cost about DKr300 (?40) per tonne more than simply incinerating the material for use as energy.

The EPA is concerned that the higher recycling targets recently proposed by the European Commission in proposed changes to the EU packaging waste directive could force Denmark to pursue the recycling option "even if environmentally this is not a good idea".

The current minimum recycling level for all packaging materials under the 1994 packaging directive is 15%, but last December the Commission proposed raising this to 20% for plastic packaging from 2006. The other EU institutions are currently scrutinising the Commission's proposals. In a common position reached in June, EU governments agreed to raise the recycling .

Danish EPA spokesman Helge Andreasen told Jyllands-Posten newspaper yesterday that one absurd consequence of enforcing the new targets at all costs could be that soft drinks, most of which are currently produced in returnable bottles, would in future be sold in disposable bottles instead.

Waste Rubber Recycling Technology


Waste Rubber Recycling Technology and Equipmen

Using thermolysis (heat decomposition), waste rubber such as tires can, with low environmental impact, be reduced to constituent, reusable elements. Technical or activated carbon and a fuel mix are the ultimate end products. The technology also is practical for recycling of other kinds of waste or scrap rubber, plastic/polyethylene packing, or other organic wastes. The process is fire- and blast-safe since it is run at low temperature.

Worn tires are chopped into 300- to 400-mm pieces and fed in batches to charge casks that are automatically conveyed to the charging chamber. The materials are then taken from the charging chamber to the thermolysis reactor, where they are exposed to heat for 90 minutes. At this stage, the rubber waste materials are thermally decomposed into gaseous and solid products. The gas products are sent from the thermolysis chamber to the separators to be cooled. Oil products of thermolysis are separated from water and supplied to the collector unit, and then poured to tanks. Ten percent of the collected oil is used to power the recycling plant; the noncondensable combustible gas is used to heat the reactor chamber.