應用化學專業(yè) 畢業(yè)論文文獻翻譯 中英文對照

1、本科畢業(yè)設計——文獻翻譯1Operation of plate rectification towerAbstract:The influencing factors,abnoimal phenomenon and rectification process were analyzed to direct actual operationKey words: rectification tower,recification,reboil

2、er,operationDistillation column is a multi-stage partial vaporization and partial condensation according to the different components in the mixture volatility in each floor tower board to achieve the separation of a mixt

3、ure of various components of the tower gas-liquid contact device, also known as distillation. A plate column and packed column types. According to mode of operation are divided into continuous distillation and batch dist

4、illation. Steam from the bottom of the column entry, and the decline in liquid countercurrent contact with the two in contact, the drop in the volatile liquid (low boiling point) components is continuously transferred to

5、 the steam. The difficulty of steam volatile (high boiling) component continued to decline in the transfer of liquid, steam the closer the top of the tower, the higher the concentration of its volatile components, while

6、the decline in the closer tower bottom liquid, its hard to be more volatile components rich set, to achieve component separation. Steam rising from the top of the tower into the condenser, the liquid part of the condensa

7、te as reflux liquid to return into the distillation tower, the rest is removed as distillate. Tower bottom outflow of liquid, some of which into the reboiler, thermal evaporation, the steam back to tower, and the other p

8、art of the liquid as residua release.Compared with other chemical unit operations,distillation unit,although relatively simple,single production run that often appear in a variety of problems affecting the operation of t

9、he distillation unit,leading to tower top orbottom of product failure,severe constraints of production equipmentthe operation resulting in product loss.1.Regular changes in process conditions of distillation column1.1 Re

10、boiler temperatureUnder the same operating pressure,raising the temperature of the reboiler,the volatile components in the tower liquid to reduce,at the same time,the rising vapor velocity increases,and help to improve t

11、he efficiency of mass transfer.If products from the top of the tower,the tower reactor discharge of difficult volatiles volatile components to reduce and reduce losses.If the tower reactor effluents for the product,it ca

12、n improve product quality tower discharge of volatile components 本科畢業(yè)設計——文獻翻譯3increased,and the stripping section of the load increases,may be poor due to the separation caused by the tower reactor products of inferior q

13、uality,which entrained volatile components increased.Feeding restructuring concentration increased,the feeding mouth move down and vice versa,then move up.The same time,operating temperature,back flow and operating press

14、ure must be adjusted accordingly in order to ensure the stability of the distillation operation.Distillation,increasing the reflux ratio,can improve the quality of the product,but the reflux ratio is too large,the inner

15、loop of the tower increased,increasing energy consumption.Reduction of the reflux ratio,the tower gas-liquid contact is not good,the balance to damaged and therefore the mass transfer efficiency decreased.The same time,t

16、he operating pressure drop,difficult volatile components easily brought to the top of the tower,resulting in a substandard product.2 Anomalies in the distillation column during operation2.1 Plate capacityRectifying secti

17、on tray downcomer overflow liquid transportation,however,that the tower upper part of the beginning of flooding,a phenomenon known as downcomer obstruction or liquid flooding.Its causes is to block the liquid leaving the

18、 tower board level rise in the downcomer plate between mist entrained excessive leaving the tray efficiency to reduce entrainment of this phenomenon is known as the excessive fog or steam flooding,the reason is the relat

19、ivein the gas while the tower board bubbling area is too small.2.2 Plate foulingSediment cumulative to the board of board of the tower is an important issue,trays of dirt will tower premature flooding will reduce the pla

20、te efficiency.Plate scaling phenomenon:(1)The reflux ratio is not high on liquid pan;(2)The pressure drop increase between the tray;(3)Increase the reflux ratio on the bottom of the column temperature,flow or reboiler lo

21、ad does not have any impact,if the reflux ratio to the heat balance and material balance of 20% to 30%,while the tower did not change significantly,then the tower must be completely full of liquid.The amount of returning

22、 tower direct stream gas pipeline through the top of the tower back to the reflux tank.2.3 Slug flows in the riserSlug flow in the riser is a distillation column running unstable,may be caused due to an unstable gas-liqu