HEAT IS WELL?

М. О. Shtabrovskaya, А. D. Мarkin

Donetsk national technical university

Natural reservoirs represent complex ecological systems existence biocenoz - communities of alive organisms (animals and plants). These systems were created within many millenia of evolution of the alive world. Reservoirs are not only collections and storehouses of water in which water is averaged on quality, but in them processes of change of structure of impurity - approach{approximation} balance continuously proceed. It can be broken as a result of human activity, in particular dump of sewage power plant.

As dumps of water and systems cooling equipment power plant bear basically "thermal" pollution it is necessary to mean that the temperature renders powerful influence on biotcenoz in a reservoir. On the one hand the temperature renders direct influence on speed of course of chemical reactions, with another - for speed of restoration of deficiency of oxygen. At rise in temperature processes of decomposition of hydrocarbonates are accelerated.

The susceptibility of alive organisms to toxic substances with rise in temperature usually increases. At rise in temperature up to +30 ^оС the gain of seaweed is reduced, the fauna is amazed, fishes become inactive and cease to be fed. Besides with growth of temperature solubility of oxygen in water decreases.

РSharp difference of temperatures which arises at dump in a reservoir of the heated up waters, brings to ruin fishes and represents serious threat to a fish economy. Influence of sewage, which temperature on 6 - 9 ^оС is higher than temperature of river water, is sensitive even for the fishes adapted to summer temperature up to +25 ^оС.

One of the most important questions at dump of warm waters in a reservoir is the organization of process of hashing of these waters with waters of a reservoir. At incorrectly organized release of warm waters the zone with the raised temperature can have the increased extent.

Reduction of the size of a zone increased is possible to achieve temperatures of water, applying various devices for the organized input of warm water in a reservoir:
    - spillways with cross-section and lateral thresholds (figure 1);
    - spillways with a distributive lattice (figure 2);
    - buttom water-release jet and egektor types (figure 3).
    At use of open spillways water mixs well up and sated with oxygen (aerated). At a jet spillway water-release is organized through branch pipes of the target collector located at the bottom of a reservoir that intensifies process of hashing of warm and cold water. At buttom water-releases water practically on all a path of system of water supply does not lose some oxygen and consequently in this case it is not required to special aeration. In a hot season cooling of warm water can be made by way in it of cold water before dump in special coolers - gradirnia, established before dump.

 

 

 

 

 

 

 

 

 

 

 

            Figure 1 - the Spillway with a threshold

1 - the waste channel; 2 - an extending part of the water-waste device; 3 - a threshold.

 

 

 

 

 

 

 

 

 

 

           Figure 2 - the Spillway jet

1 - a ferro-concrete collector; 2 - a water-final branch pipe; 3 - a laying from gravel; 4 - concrete.
 

 

 

 

 

 

 

 

 

 

 

 

Figure 3 - the Spillway with a distributive lattice

1 - a supply of water; 2 - a water-distributive lattice; 3 - a water intake; 4 - height of falling of jets of water; 5 - a level of dumped water.
 

 

Power plant dump essentially smaller quantity{amount} of heat with cooling water, rather than power stations.

Other important action for reduction of quantity of thermal dumps is use heat of cooling water, but it is connected to significant difficulties.

            Thus, thermal pollution is the basic threat to all alive on a planet. If this question will not be solved in the near future the mankind will be on itself cataclysms, gradually global all-consuming character.