INVESTIGATION OF VARIOUS SCHEMES FOR RECONSTRUCTING OF THE DESIGN DUST PREPARATION SYSTEM WHEN CHANGING THE TPP-210A STEAM GENERATOR OPERATION OF THE TRYPILLIA TPP BLOCK 4 FROM BURNING ANTHRACITE CULM TO BURNING G AND DG-1

• Дата: 2017
• Автор: Rokhman, B.
• Формат: Стаття
• Мова: rus
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2017
• Теми: steam generator; drying; dust preparation system; coal; studded zone; drying agent; slag; burner; парогенератор; сушка; система пылеприготовления; уголь; ошипованная зона; сушильный агент; шлак; горелка; система пилоприготування; вугілля; зашипована зона; сушильний агент; пальник
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/17
• Назва журналу: Vidnovluvana energetika

Using the developed calculation technique, a theoretical study of the processes of heat exchange and combustion of anthracite culm (or coals of the gas group of G and DG-100 grades) in the TPP-210A boiler of unit No. 4 of Trypillia TPP at 300 and 285 MW was carried out. It is shown that when the АШ is burned, the distribution of steam and flue gas temperatures along the boiler path is in good agreement with the experimental data of the CKTI [6] and the workshop of the Trypillia TPP. It is shown that drying of DG-100 coal with flue gases and a recirculating drying agent at  75 °C results in the deposition of moist dust in the dustlines. Increasing of the spent drying agent temperature from 75 °C to 115 °C increases the temperature margin of the drying agent on the condition of condensation of moisture to 38.9 °C, but reduces the temperature of the gases at the exit of the studded zone and the adiabatic combustion temperature due to the growth of the gas recirculation ratio up to 9.92%. A method is proposed for reducing the gas recirculation ratio by partially replacing of combustion products in the drying agent with hot air. A new concept for the reconstruction of the dust system of the TPP-210A boiler  burning gas coal, is based on five main technical solutions: 1) a highly concentrated supply of dry coal dust to the main burners in a ratio of 80-100 kg of dust per 1 kg of a transporting agent; 2)  injection of the spent drying agent into the cooled zone, which does not affect the combustion of fuel in the pre-furnace, allows to reduce the excess air in it; 3) dried fuel having lowest heat of combustion higher than that of the row coal, is supplied to the active combustion zone; 4) deep cleaning (up to 99%) of the spent drying agent from dust due to installation of a bag cyclone filter after the cyclone helps to  reduce unburned carbon; 5) not using the thermal energy of hot air for evaporating the moisture of coal. High level of explosion protection of the dust-system is achieved due to the fulfillment of three conditions: а) the volume concentration of the oxidant in the spent drying agent with allowance for air inflow in the dust-system is less than 10% due to the coal drying with flue gases; b) a large margin of the drying agent temperature to avoid condensation of water vapor; c) the velocities of the gas suspension in the dustlines lie in the required ranges selected from the condition of dust non-falling on  the pipelines walls.