EFFECT OF LIQUID FLOW RATE AND GAS FLOW RATE ON A PACKED ABSORPTION TOWER AND REPAIR OF EQUIPMENT
ABSTRACT
Trouble shooting revealed effect of liquid flow rate and gas flow rate on a packed absorption tower and repair of equipment that the exit drain value was broken due to carelessness on the part of former user of the equipment. We had to carry out glassblowing operations using borosilicate glass to construct another value. Once this was done pressure build up within the tower was restored for absorption operation to take place.
A plot of log DO/H against log a superficial gas velocity gave 2.0774 2.3037 and 1.4940 respectively for slopes at varied superficial liquid velocity.
We concluded that increase in gas flow rate lead to increase in pressure drop since the graph obtained is linear. There was a drop in slope from lower liquid rate to higher as operation neared flooding condition. This means that industrially more cost is alluded to pumping operation to be successful.
1.0 INTRODUCTION
The removal of one or more selected components from a mixture of gases by absorption into a suitable liquid is the second major operation of chemical engineering that is based on inter phase mass transfer controlled large by rates of diffusion
Gas absorption defined by Perry is a unit operation in which a soluble components of a gas mixture are dissolved in a liquid. The inverse operation is called stripping or description.
In gas absorption a soluble rapour is absorbed from its mixture with an inert gas by means of a liquid in which the solute gas is more or less soluble. The washing of ammonia for a mixture of ammonia and air by means of liquid water is a typical example. The solute is subsequently recovered from the liquid by distillation and the absorbing liquid can be either discarded or reused. An acetone air mixture passed through a gas stream can recover acetone by its dissolving in the gas and allow the air to pass out. In each of the example given only physical process take place with no chemical affect appreciable. However when oxides of nitrogen are absorbed dioxide is absorbed in a solution of sodium hydroxide, a chemical reaction occurs, the nature of which influences the actual rate of absorption
In considering the design of equipment to achieve gas absorption, the main requirement is that gas be brought into intimate contact with the liquid and the effectiveness of the equipment will largely be determined by the success with which it promotes contact between the two phases.
