The analysis of physical and chemical methods of water treatment for boiler houses and thermal power plants.
Students Name: Kalytynets Illia
Qualification Level: magister
Speciality: Heat and Power Engineering
Institute: Institute of Power Engineering and Control Systems
Mode of Study: part
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: Kalytynets I.M., Kovalenko T.P. (heаd). The analysis of physical and chemical methods of water treatment for boiler houses and thermal power plants. Mаster’s thesis. - Lviv Polytechnic Nаtionаl University, Lviv, 2022. Natural water, which is divided into atmospheric (rain, fog, snow), surface (rivers, lakes, ponds, swamps), groundwater (artesian wells, mine wells) and sea (seas, oceans), always contains various impurities. The nature and quantity of impurities present in water determines the quality of water, ie characterizes the possibility of its use for various purposes in industry and in everyday life. Along with natural, there is a production and domestic water cycle, which is created as a result of its consumption for various purposes (cooling, municipal water supply and the like). Impurities enter the water at all stages of the cycle. When moisture condenses in the atmosphere, oxygen, nitrogen, and carbon dioxide dissolve in the condensate according to their partial pressures, and in industrial areas - a significant number of oxides of sulfur and other products contained in flue gases. The total salinity of precipitation averages 10 milligrams/dm3. Leaking through the soil, water meets with various mineral salts (NaCl, Na2SO4, MgSO4, CaCO3, silicates) and organic matter, dissolves or mechanically captures them. With the simultaneous presence in the water of oxygen, organic matter and microorganisms (bacteria) that are constantly in the surface layers of the soil, conditions are created for the transition of the main components of a number of organic substances in mineral acids. phosphorus). Acids formed in groundwater interact with widespread limestones - calcium carbonates, iron, dolomites CaMg (CO3)2 and other rocks, which leads to the ingress of well-soluble bicarbonates Ca, Mg, Fe. High-quality water treatment and rational water-chemical regime are a guarantee of reliability, economy, trouble-free heat and power equipment and heating networks. The urgency of the problem is currently high, as the composition of surface water is significantly affected by wastewater discharges and personal waste of industrial enterprises, resulting in water pollution by various chemical compounds of inorganic and organic nature, which negatively affects thermal power facilities. That is why it is necessary to constantly improve the technology of water treatment and water-chemical regimes in boiler houses and thermal power plants. The object of research is water treatment technologies and water-chemical regimes of boiler-houses and thermal power plants. The subject of research - physico-chemical methods of purification and desalination of boiler water and thermal power plants. The purpose and objectives of research. The aim of the work is to improve the physico-chemical methods of purification and desalination of boiler water and thermal power plants. To achieve this goal it was necessary to perform the following tasks: - to analyze the main characteristics of natural water; - to analyze the importance of water in the heat industry; - to conduct research on preliminary water purification and physico-chemical processes of water treatment; - to analyze water filtration on mechanical filters; - to study the process of water desalination. In this master’s qualification work physico-chemical methods of water purification and desalination for thermal power equipment of boiler houses and thermal power plants are considered. Water treatment and water-chemical regimes prevent the formation of all kinds of deposits and corrosion damage on the inner surfaces of thermal power equipment, elements of the network water route, including heaters, saves burning fuel because deposits are formed on heating surfaces with high thermal resistance. which causes large fuel losses. Due to the thermal resistance of the scale layer at its thickness of 0.2 mm, the boiler wall temperature can differ greatly from the boiler temperature and in modern boilers reach 700 ° C, which leads to accidental rupture of boiler tubes, which also has a negative impact on energy conservation. Gives a reduction in the discharge of environmental pollutants from thermal energy facilities into the biosphere, which negatively affects the health of the population. Modern physicochemical, ion-exchange methods of water purification are considered both for heat and power equipment of low, high pressure of boiler-houses and thermal power plants, and for thermal networks, sewage. Devices, principles, methods of calculations and optimization of some processes that occur in the preparation of water for power boilers and heating networks are described. In the section of economics, the payback period of the project, which will be 3.7, was calculated. The cost of demineralized water obtained in the installation will be UAH 1.5. The cost of deeply desalinated water is 2.24 UAH / m3. The deaerator is taken as the object of automation. Its contours of automation are described and the specification on means of automation is made. Key words: boiler house, heat and power equipment, water treatment scheme, physical and chemical methods of water purification, water - chemical regimes.