Study On Energy Conversion And Stirring Characteristics Of Self-stirring Reactor Driven By Pressure

Stirred reactors are widely used in the metallurgical and chemical industries.The pressure-driven self-stirring reactor utilizes the high-temperature and high-pressure fluid self-energy,and achieves agitation through the driving wheel,which not only realizes efficient mixing of materials and utilization of energy,but also overcomes problems such as difficulty in mechanical sealing of the conventional stirred reactor.The reactor combines the dual advantages of a tubular reactor and a kettle reactor.The research and structural optimization of this new reactor performance have theoretical and practical significance.Previous studies have demonstrated that pressure can drive the feasibility and initial flow characteristics of a self-stirring reactor.On this basis,based on physical experiments,theoretical calculations,numerical simulations and factorial analysis methods,the influence of the structural type of the driving wheel on the energy conversion and the stirring characteristics of the key components of the self-stirring reactor are studied,including the investigation of the fluid.The influence of pressure,liquid level and other factors on the stirring speed,driving wheel energy,mixing uniformity and stirring flow field.The main results are as follows:(1)When the pressure is 2.5 MPa and the liquid level height H/D is 1/4-7/8,the stirring speeds of the impact drive wheel,the flat plate drive wheel and the slanting drive wheel are 56-82 rpm,59-78 rpm and 48-69 rpm,when the pressure is 0.5-2.5 MPa,the liquid level is the same,the stirring speed of the impact drive wheel and the flat drive wheel is greater than the stirring speed of the slanting drive wheel,and the energy conversion of the impact drive wheel and the flat drive wheel The ability is better than the slanting drive wheel.(2)Through the formula and N平=F·v板 and (?)calculation the result of the driving wheel is obtained.When the pressure is 2.5 MPa and the liquid level height H/D is 1/4-7/8,the energy gain of the impact drive wheel and the flat drive wheel are 6.4-9.3 W and 5.6-7.4 W respectively,when the pressure is 0.5-2.5 MPa,when the liquid level is equal,the energy of the impact drive wheel is greater than that of the flat drive wheel.The performance of the impact drive wheel is slightly better than that of the flat drive wheel.(3)In the solid-liquid two-phase system,the concentration of solid particles at the stirring shaft is the lowest,and as the distance from the stirring shaft increases,the particle concentration also becomes larger,and the closer to the wall surface,the smaller the concentration gradient.(4)The PIV technique was used to study the agitated flow field in the self-stirring reactor.When the influencing factors were the same,the fluid flow rate under the impact drive wheel was greater than the fluid flow rate under the action of the flat drive wheel The flow velocity near the agitating paddle and near the wall is small,the flow vetocity in the main flow region is large;the radial flow velocity is large,the axial flow velocity is small,and the fluid mainly flows through the circulation.(5)In this paper,we use the factor analysis theory to derive the similarity correlation equation of the pressure-driven self-stirring reactor driving wheel,and calculate the equation coefficients based on the experimental results,and get:N=9.53·10-7D3u2R1ρIt is verified that the model calculation results are in good agreement with the experimental data.