未知, 2019-12-16 16:21, 次浏览
You never know how to choose the waste gas purification tower~~~
The selection of the general principles for the selection of the waste gas purification tower and the reasonable selection of the type of the tail gas absorption tower are the primary links for the design of the tower equipment. The main factors to be considered in the selection are: material properties, operating conditions, performance of tower equipment, and manufacturing, installation, operation and maintenance of tower equipment.
Waste gas purification tower
（1）与物性有关的因素 a、易起泡的物系，如处理量不大时，以选用填料塔为宜。因为填料能使泡沫破裂，板式塔则易引起液泛。 b、具有腐蚀性的介质，可选用填料塔。如必须用板式塔，宜选用结构简单、造价便宜的筛板塔盘、穿流式塔盘或舌形塔盘，以便于更换。 c、具有热敏性的物料减压操作，以防过热引起分解或聚合，故应选用压力降较小的塔型，如采用装填规整填料的塔、湿壁塔等。当要求真空度较低时，宜用筛板塔或浮阀塔。 d、粘性较大的物系，可以选用大尺寸填料的填料塔，板式塔的传质效率则太差。 e、含有悬浮物的物料，应选择液流通道较大的塔型，以板式塔为宜。可选用泡罩塔、浮阀塔、栅板塔、舌形塔或孔径较大的筛板塔等，不宜使用小填料。 f、操作过程中有热效应的系统，用板式塔为宜。板式塔的塔盘上积有液层，可在其中安装换热管，进行有效的回执或冷却。
(1) factors related to physical properties A. if the treatment capacity of foaming system is not large, it is better to select packing tower. Because fillers can cause bubbles to burst, plate pagodas are prone to flooding. B. for corrosive media, packed tower can be selected. If plate tower must be used, sieve plate tray, through flow tray or tongue tray with simple structure and low cost should be selected for easy replacement. C. pressure reducing operation of materials with thermal sensitivity to prevent decomposition or polymerization caused by overheating, so tower type with smaller pressure drop shall be selected, such as tower with structured packing, wet wall tower, etc. When low vacuum is required, sieve plate tower or float valve tower should be used. D. for the system with large viscosity, the packed tower with large size packing can be selected, while the mass transfer efficiency of the plate tower is too poor. E. for materials containing suspended solids, the tower type with large liquid flow channel shall be selected, and the plate tower is preferred. Bubble cap tower, float valve tower, grid plate tower, tongue shaped tower or sieve plate tower with large aperture can be selected, and small packing is not suitable. F. for the system with thermal effect during operation, plate tower is suitable. There is liquid layer on the tray of plate tower, in which heat exchange tube can be installed for effective receipt or cooling.
（2）与操作条件有关的因素 a、若气相传质阻力大，宜采用填料塔，填料层中气相呈湍流，液相为膜状流。反之，受液要控制的系统，宜采用板式塔，因为板式塔中液相呈湍流，用气体在液层中鼓泡。 b、大的液体负荷，可选用填料塔，若用板式塔时宜选用气液并流的塔型，如喷射型塔盘或用板上液流阻力较小的塔型，如筛板和浮阀。此外，导向筛板塔盘和多降液管筛板塔盘都能承受较大的液体负荷。 c、低的液体负荷，一般不宜采用填料塔。 d、液气比波动的适应性，板式塔优于填料塔故当液气比波动较大时宜用板式塔。 e、操作弹性，板式塔较填料塔大，其中以浮阀塔为最大，泡罩塔次之，一般地说，穿流式塔的操作弹性较小。
(2) factors related to the operating conditions A. if the mass transfer resistance of the gas phase is large, the packing tower should be used. The gas phase in the packing layer is turbulent and the liquid phase is membrane flow. On the contrary, for the system to be controlled by the liquid, the plate tower should be used, because the liquid phase in the plate tower is turbulent and the gas bubbles in the liquid layer. B. for large liquid load, the packed tower can be selected. If the plate tower is used, the tower type of gas-liquid parallel flow should be selected, such as jet type tray or the tower type with less liquid flow resistance on the plate, such as sieve plate and float valve. In addition, both guide sieve tray and multi downcomer sieve tray can bear large liquid load. C. packing tower is generally not suitable for low liquid load. D. the adaptability of the fluctuation of liquid gas ratio, plate tower is better than packing tower, so plate tower should be used when the fluctuation of liquid gas ratio is large. E. the operating flexibility of plate tower is larger than that of packed tower, in which the floating valve tower is the largest and the bubble cap tower is the second. Generally speaking, the operating flexibility of through flow tower is smaller.
（3）其它因素 a、对多数尾气吸收塔情况，塔径大于800mm时，宜用板式塔，小于800mm，则可用填料塔。但也有例外，鲍尔环及某些新型填料在大塔中的使用效果优于板式塔。同时，塔径小于800mm时，也有使用板式塔的。 b、一般来说填料塔比板式塔重。 c、大塔以板式塔造价较廉。因填料价格约与塔体的容积成正比，板式塔按单位面积计算的价格，随塔径增大而减小。
(3) other factors A. for most tail gas absorption towers, if the diameter of the tower is greater than 800mm, plate tower should be used. If the diameter is less than 800mm, packed tower can be used. But there are some exceptions. The application effect of Bauer ring and some new packing in large tower is better than that of plate tower. At the same time, when the tower diameter is less than 800mm, plate tower is also used. B. generally speaking, packed tower is heavier than plate tower. C. the cost of plate tower is relatively low. Because the price of packing is proportional to the volume of the tower, the price of plate tower calculated by unit area decreases with the increase of tower diameter.