Research of gas-dynamic processes of motion of combustion products of blast-air heaters

The article deals with the methods of physical modeling of gas-dynamic processes and the calculation of aerodynamic resistance in the motion of combustion products on the exhaust system. The analysis of echoing methods for increasing the diversion of combustion products of hot stoves has been carried out and their main disadvantages have been identified. The basic principles of creation of mathematical models of flue gas flow on an exhaust system are considered and an estimation of their adaptability to the really conditions. The main reasons for the reduction of traction in the exhaust system of the blast-furnace shop of Dneprovsky DMZ are revealed. The research of the state of refractory lining was conducted and the main reasons of a short period of its work were revealed. The ejection and injection phenomena on the basis of which several ways of increasing traction in the chimney tract are considered. Investigations of the level of pressure of combustion products at the exit from the combustion chamber on the existing air heaters have been carried out. The influence of taking blast furnace on draft through air heaters on the duration of service life of refractories of exhaust system and the degree of mixing of combustion products during tangential feeding to common forests is revealed. The calculation of pressure losses in the smoke boron under the conditions of the blast-furnace shop of Dneprovsky DMZ is carried out. Considered ways to increase the value of traction for effective smoke removal from blast air heaters. During the experiments, the distribution of flows between the ejector and around the nozzle was detected. Conclusions are made on the necessity of using some methods for increasing traction in smoke boron and the correspondence of some coefficients of local resistance to experimental data. It is suggested to conduct further physical experiments to specify the coefficients of local resistance.

Basic areas of the secondary energy resources use in the blast-furnace ironmaking and application of heat pumps

Under the present-day conditions of blast-furnace shop operation, the use of low-potential SERs seems to be the most promising measure with regard to reduction of cast-iron production cost. Proposed measures on improvement of blast-furnace gas calorific power due to the reduction of its moisture content allow the blast-furnace air temperature increase and coke consumption reduction. Also proposed is partial transfer of excess heat from the blast-furnace gas to combustion air by means of the system of heat pumps, which allows increase in calorimetric combustion temperature.In this paper, main parameters are calculated of the heat pump system operation under the conditions of blast-furnace shop at the increased top gas temperature. This paper presents heat pump system operating efficiency and determines conversion factor for the specific conditions (COP).