新型板式旋转填料床的开发及性能研究

发布时间：2018-05-24 01:03

本文选题：超重力 + 旋转填料床　；参考：《中北大学》2017年硕士论文

【摘要】：超重力旋转填料床是一种高效传质和反应设备。超重力填料是决定其气液传质效果的核心部件。在除尘等含杂质较多的化工过程中,传统丝网和散装填料极易出现填料堵塞和填装不均等现象,由此造成了气相阻力增大、设备动平衡差和气液分布不均匀等问题,对设备的长期、高效和稳定运行均有不利影响。为此,本文设计和开发了一种错流大通道规整板式填料,通过减小转子直径来实现大气量处理,将多孔隙填料改为多孔大通道板式填料,同时具有防堵和动平衡稳定等优点,实现低压降高传质特性。首先利用CFD技术研究了板式填料对流体的作用规律。研究表明,新型板式填料的安装方式(板尺度、板倾角和夹角)均对流体运动产生影响,对气相具有扰动作用,可延长气相停留时间;对液相具有成膜效果和雾化作用。以上机制均有利于气液混合性能的提高和传质过程的强化。以空气-水为实验体系,对新型板式旋转填料床的压降性能进行研究,采用单因素实验和正交实验方法,考察转速N、液量L、气量G、周向板数N1和径向板数N2对新型板式填料压降性能的影响。结果表明,新型板式旋转填料床具有低压降特性(25~275Pa);压降值随着各个因素增大而增大,当径向板数为4,周向板数为5时,压降变化出现拐点,后趋势平缓;正交实验结果表明气量G是影响压降最重要的因素,压降随气量G呈抛物线型增长,转速N和液量L对压降影响较小,径向板和周向板间存在有交互作用。与不同文献对比,新型板式填料压降低于逆流分层式和折流式分别为91.25~93.75%和84.28~91.67%,表现出较优的压降性能。以NaOH-CO2为实验体系,对新型板式旋转填料床的传质性能进行研究,采用单因素实验和正交实验方法,考察转速N、液量L、气量G、周向板数N1和径向板数N2对新型板式填料传质性能的影响。结果表明,新型板式旋转填料床一定程度上强化了传质效果,kLa最大值可达4.3s-1,且kLa均随参数的增大而增大;正交实验表明各个参数对kLa影响较为接近,且径向板数影响最大,表明在径向板对液相的雾化剪切作用在传质过程中发挥了重要作用,径向板和周向板存在交互作用,以板组合形式影响填料床传质性能。与不同文献对比,新型板式填料传质系数高于分层式旋转填料约70.4%~88.1%,高于错流多级离心雾化填料约89.5%~95.0%,一定范围内表现出了优良的传质性能。对超重力环境下新型板式填料、鲍尔环填料和丝网填料的传质及压降性能进行了对比实验研究。结果表明,相同操作条件下,丝网填料床传质性能最优,丝网填料床传质性能比新型板式填料床传质性能平均高出0.14~0.38,新型板式填料床与鲍尔环填料床传质性能接近,平均相差0~15%;相同操作条件下,压降对比实验显示丝网填料床压降值鲍尔环填料床压降值新型板式填料床压降值,丝网填料床压降值是新型板式填料床压降值约0.45~1.2倍,损失一定传质效能的情况下,可以实现低压降。最后,对新型板式填料床进行了脱除硫化氢和除尘实际应用研究,结果表明在相同条件下,新型板式旋转填料床的脱硫率为85%~94.2%,粉尘去除率为89.3%~95.3%,基本满足了一般的工业需求,具有广泛的通用性。
[Abstract]:The super gravity rotating packed bed is a kind of high efficient mass transfer and reaction equipment. The super gravity filler is the core component determining the effect of gas and liquid mass transfer. In the chemical process, such as dust removal and so on, the traditional screen and bulk packing are easily blocked and unevenly filled, resulting in the increase of the gas phase resistance and the poor dynamic balance of the equipment. The problem of uneven distribution of gas and liquid has adverse effects on the long-term, efficient and stable operation of the equipment. Therefore, this paper designs and develops a kind of large channel regular plate packing with large passages by reducing the diameter of the rotor to achieve large air volume treatment. The multi pore packing is changed into a porous and large channel plate type filler, and it has the anti blocking and dynamic balance stability at the same time. The mass transfer characteristics of low pressure drop are realized. First, CFD technology is used to study the effect of plate packing on fluid. The study shows that the installation mode of the new plate type packing (plate scale, dip angle and angle) has influence on the fluid movement, and the gas phase can be extended to prolong the gas phase residence time, and the liquid phase has a film forming effect. The above mechanism is beneficial to the improvement of gas and liquid mixing performance and the enhancement of mass transfer process. The pressure drop performance of the new type plate type rotating packed bed is studied with air water as the experimental system. The single factor experiment and orthogonal experimental method are used to investigate the speed N, the liquid quantity L, the gas amount G, the circumferential plate number N1 and the radial plate number N2 to the new type plate type. The results show that the pressure drop characteristic (25~275Pa) of the new type plate type rotating packed bed has a low pressure drop characteristic (25~275Pa). The pressure drop value increases with the increase of various factors. When the number of radial plates is 4 and the number of circumferential plates is 5, the pressure drop varies with the turning point and the trend is slow. The orthogonal experimental results show that the air volume G is the most important factor affecting the pressure drop, and the pressure drop follows the pressure drop. The air volume G has a parabolic growth, the speed N and the liquid amount L have little influence on the pressure drop, and there is interaction between the radial plate and the circumferential plate. Compared with the different literature, the pressure drop of the new type plate type packing is lower than the counter current stratification type and the baffle type is 91.25~93.75% and 84.28~91.67% respectively. The performance of the pressure drop is better than that of the counter current. The experimental system of NaOH-CO2 is a new model. The mass transfer performance of the plate type rotating packed bed was studied. The effects of rotational speed N, liquid volume L, gas volume G, the number of circumferential plate number N1 and radial plate number N2 on mass transfer performance of the new type plate filler were investigated by single factor experiment and orthogonal experiment. The results showed that the new type plate type rotating packed bed strengthened the mass transfer effect to a certain extent, and the maximum value of kLa could reach 4.3s-1, And kLa increases with the increase of the parameters, and the orthogonal experiment shows that the influence of the parameters on the kLa is close, and the number of radial plates has the greatest influence. It shows that the atomization shear action of the radial plate plays an important role in the mass transfer process, and the radial plate and the circumferential plate have interaction, and the mass transfer performance of the packed bed is affected by the plate combination. Compared with different literature, the mass transfer coefficient of the new type plate type filler is higher than 70.4%~88.1%, which is higher than 89.5%~95.0% for the multistage centrifugal atomizing filler. The mass transfer performance is excellent within a certain range. The mass transfer and pressure drop performance of the new type packing, Bauer ring packing and screen filler in the super gravity environment are carried out. The results show that under the same operating conditions, the mass transfer performance of the screen packed bed is the best, the mass transfer performance of the screen packed bed is 0.14~0.38 higher than that of the new type plate packed bed, and the mass transfer performance of the new plate packed bed and the Bauer ring packed bed is close to 0~ 15%; under the same operating conditions, the pressure drop comparison experimental display wire The pressure drop value of the pressure drop value of the packing bed of the mesh packing bed is the pressure drop value of the new plate packed bed with the pressure drop value of the Bauer ring packing bed. The pressure drop value of the screen packed bed is about 0.45~1.2 times of the pressure drop of the new type packing bed, and the low pressure drop can be achieved under the condition of a certain mass transfer efficiency. Finally, the practical application of the removal of hydrogen sulfide and dust removal is carried out on the new type of plate packed bed. It shows that under the same conditions, the desulphurization rate of the new type plate type rotating packed bed is 85%~94.2% and the dust removal rate is 89.3%~95.3%, which basically meets the general industrial demand and has extensive generality.
【学位授予单位】：中北大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ051.1

【参考文献】