Abstract on the theme: "The substantiation and research of the device structure measurement of the sewage dissolved oxygen concentration"



Problems of ecology play a huge role in the life of each individual man and society as a whole. The most important such problem is water pollution. It is known that water is crucial in creating and sustaining life on Earth, plays a crucial role in metabolic processes that form the basis of life.

To date, a terrible picture in terms of water in eastern Ukraine, particularly in Lugansk, Donetsk, Mykolayiv and Odesa regions. Here, due to a weak system of cleaning contaminated industrial water people are forced to drink the water, with deviations from the norm to 80 percent [1].

In order to protect surface waters from pollution a necessary condition for a waste water treatment. The best way to protect surface waters from sewage is to develop and implement an anhydrous and non-waste production technologies, the initial phase of which is the creation of water recycling. To organize the system of water recycling is necessary to introduce a range of treatment facilities and installations, which allows you to create a vicious cycle of industrial and domestic sewage. With this method of water treatment waste water all the time are in the back and hit them in the surface water is completely excluded [2].

As a result of the fact that the composition of wastewater varied, there are different kinds of treatment, such as: mechanical, physical, chemical, biological and other treatment of water can be produced as a single species or complex, depending on the pollutant.

Mechanical cleaning is necessary for the discharge from waste water insoluble mineral and organic impurities, most often it is a method of pre-treatment and is designed to prepare wastewater for biological or physico-chemical methods of purification. The end result of such treatment a reduction in suspended solids and 90%, and organic matter to 20% for industrial waste water and 60% for the household.

Chemical and physical-chemical cleaning methods play a significant role in the treatment of industrial wastewater. They are used both independently and in combination with mechanical and biological methods. Chemical cleaning is achieved by reduction of insoluble impurities of up to 95% soluble and 25%.

Biological treatment - often used in practice, the method of treatment of domestic and industrial wastewater. The basis of this method is the process of biological oxidation of organic compounds contained in wastewater. Biological oxidation by microbial communities that include a variety of bacteria, protozoa, and a number of more highly organized organisms, algae, fungi, etc., interconnected in a single set of complex relationships (metabioza, symbiosis and antagonism). Wastewater is treated in aeration tanks - special closed containers, which passed slowly sinks, oxygen-rich and mixed with activated sludge. Activated sludge is a combination of heterotrophic microorganisms and small invertebrates (mold, yeast, water, fungi, rotifers, etc.), as well as the solid substrate. It is important to correctly choose the temperature, pH, additives, mixing condition, an oxidant (oxygen) to the maximum extent contribute to the intensification of gidrobiotsenoza constituting the activated sludge. This method is most efficient and economical. Effectiveness of cleaning stations reaches 98%. Water output is compared in quality with technical water and can be used to meet the needs [3].

Dissolved oxygen is a key parameter in biological wastewater treatment, as oxygen concentration determines the nature and rate of aeration processes in tenk.

A huge part of the energy consumed by treatment facilities used for the aeration of activated sludge. In consequence of that problem is cost control and management of lower energy consumption is very important for each treatment plant, therefore necessary to optimize the flow of oxygen in the aeration tenk. At the head of optimization is correct and accurate measurement of dissolved oxygen. Therefore, continuous and accurate measurement of oxygen is of paramount importance.

Result of the master's work will be studies related to the elucidation of the dependence of measurements of dissolved oxygen in wastewater from various non-informative parameters such as temperature, pressure and the like. Also as a result will get a flowchart detailing and build a mathematical model of the device.

Currently, widespread application was received and dissolved oxygen sensors based on electrochemical measurement methods (polarographic, amperometric, etc.). Such sensors require constant maintenance (cleaning, calibration, replacement membranes and electrolyte polishing the anode). It is possible to retain the values evidence within certain limits. When using sensors based on electrochemical methods, reliability depends on the quality of works on servicing the sensor.

To measure the concentration of dissolved oxygen used by the quenching associated with the random collisions between the fluorophore and the quencher (oxygen), called dynamic, or quenching in collisions.

Further studies will be directed to the sensor temperature correction, as well as to study the effect of non-informative variables and construct a mathematical model of the instrument for measuring dissolved oxygen in wastewater.

Literature

  1. Загрязнение и очистка воды в Украине [Электронный ресурс] - Режим доступа: http://www.filtryplus.com.ua/articles/zagryaznenie_vody.html

  2. Способы очистки сточных вод от загрязнения - защита гидросферы [Электронный ресурс] - Режим доступа: http://www.ecology-portal.ru/publ/12-1-0-389.html

  3. Биологическая очистка сточных вод | Методы очистки сточных вод [Электронный ресурс] - Режим доступа: http://waterclean.com.ua/biologicheskaya-ochistka-stochnyih-vod.html

While writing this essay, Master's work is not completed yet. Final date: December 2011. Full text of all materials on the subject can be obtained from the author or his manager after that date.