Природообустройство и водопользование»
Global Warming
Global warming is the increase in the average temperature of the Earth’s
atmosphere and surface in recent decades. Increasing global temperatures will
cause sea level to rise and is expected to increase the intensity of extreme weather
events and to change the amount and character of precipitation. Other effects of
global warming include changes in agriculture, trade routes, glacier melting,
increase of diseases, etc.
There is ongoing political and public debate worldwide regarding what
actions should be taken to reduce or reverse future warming or to adapt to its
expected consequences. Most national governments have signed and ratified the
Kyoto Protocol aimed at reducing greenhouse gas emissions. Global warming
results in climate change and is caused by human influence.
The Earth’s climate changes in response to external forcing, volcanic
eruptions, atmospheric greenhouse gas concentration, etc. The greenhouse effect is
the process by which absorption and emission of infra-red radiation by atmospheric
gases warms our planet. Scientists predict that the effect of adding greenhouse
gases is to produce a warmer climate and climate sensitivity to changes.
Nuclear Pollution
The first time that people discovered the dangers of nuclear power was when
the atomic bomb was dropped on Hiroshima in 1945. The effect was destructive to
human health and environment. Many living organisms died later as a result of
nuclear radiation sickness. The most severe catastrophe with long-term
consequences was the accident at Chernobyl in1986. Thousands hectares of land
are contaminated with radioactive elements.
Nuclear waste requires sophisticated treatment in order to isolate it from
interacting with the biosphere. High levels of contamination may pose major risks
to the environment and people dependent on the absorbed dose. Radon is the most
dangerous gas that naturally evolves from uranium.
Science has not yet found a safe method of permanent disposal of high level
radioactive wastes. Some radioactive substances have a half-life of more than
10,000 years. Attempts to store nuclear waste, to bury it underground, to put the
nuclear waste into deep ocean water, to dispose it in space have not been
successful.
Greenpeace
Greenpeace is an international environmental organization founded in
Canada in 1971. It is known for its campaigns to stop atmospheric and
underground nuclear testing and commercial whaling.
Greenpeace has 27 offices in 41 countries all over the world, which mobilize
volunteers for protests against the pollution of our planet.
The official mission and statement of Greenpeace is described as:
“Greenpeace is an independent campaigning organization which uses non-violent,
creative confrontations to expose global environmental problems, and to force
solutions for a green and peaceful future. The goal of Greenpeace is to ensure the
ability of the Earth to natural life in all its diversity.”
Greenpeace uses direct actions to attract attention to important
environmental problems such as harmful radiation, marine reserves, saving of
ancient forests, catastrophic climate change etc.
The members of Greenpeace also take part in international conferences on
the problems of peace and nuclear disarmament, elimination of toxic chemicals,
prohibition of genetic engineering, radioactive waste etc.
But Greenpeace is criticized by some governments for being too extreme.
Эксплуатация транспортно-технических машин и
комплексов»
Bulk Handling Equipment
The grabbing cranes are mostly used to handle bulk cargoes. Bucket
elevators were replaced by pneumatic plants. The flexible intake pipes on
pneumatic grain plant extract grain from stowage. They can clean decks and holds
to the last grain. The speed of handling depends on the diameter of pipes and the
intake nozzle. For safety precautions a fine-mesh filter is fitted in the pipe-line.
The handling plant speeds up the flow of bulk materials and feeds conveyor to
storage places.
Handling liquid bulk cargoes, such as liquefied gas, wines, vegetable oils, is
carried out by pumping systems of high capacities. Floating and submarine host
connections of large diameter connect shipboard and quay terminals.
To increase rates of ore handling the material is mixed with water and
assumes the consistency like that of crude oil. This is pumped through 12-inch
diameter hoses. The solid material settles rapidly and water is decanted by means
of a suction pipe, lowered to the mass. The ships are fitted with water jet units.
When the surface water is removed the consistency of a solid mass with water
content is only slightly higher than in conventionally handled dry ores. There are
no substantial losses through spillage and the operating costs are much lower than
for traditional methods.
Bag Loading Equipment
Bag loading is an effective and widely used form of packaging industrially
manufactured powders and granulated products. Bag loading is mechanized in 2
variations: single bag loading with bag loading machines and palletized bag
loading. Palletizing is based on the collective principle: up to 60 bags are united to
form a large storage, transloading and shipment unit.
There are bag loading machines of 30 different models to suit any particular
operating conditions. They provide optimal reliability, safety and low installation
costs.
The adjacent conveyor belt feed system permits bags to be fed to any desired
loading point. The loading machines for the side loading are mounted on mobile
ramps and can be rolled alongside the ship.
Ship loading installations for loading bagged materials can supply both
stationary and mobile plants with standard loading belts. The difference in height
between the dock and the hold of the ship is bridged by an inclinable belt extension
which can be raised and lowered by way of an electro-pulley block.
Handling of Logs
Logs transported by water are in random length and in pre-cut length
bundles. Log bundles can be handled by a 30-ton crane with a hydraulic grapple.
The length of logs may vary from 2 to 7 meters. The crane is equipped with an
electric weighing and calculating apparatus, which measures the solid cubic
volume of the random length bundles by the Archimedean principle. The bundle is
weighed both in air and water and the difference between the weights is the cubic
volume in solid measure. The grapple is heavy enough to sink a bundle into water.
By the aid of an assistant on the ground the crane operator can easily and quickly
guide the jaws under the bundle and hoist it.
The crane hoists the bundles onto a 9.2 m wide chain deck, where the
bundles are spread out by means of a chain conveyor consisting of 3 sections. Each
section has a variable speed drive which is independently adjustable. The third
section of the chain deck is an elevating conveyor, which hoists the logs to the
deck.