Regarding full reflux operation
Thread Content
If the parameters of the distillation tower become abnormal, it usually results in the product not meeting quality standards. At this time, full reflux operation is generally used, and here a question arises: does full reflux at this stage mean no feed and no withdrawal, or is withdrawal continued? I would appreciate it if experts could give some guidance and explain the various possible situations and their causes! Thank you all, fellow sailors!
Full reflux means that there is no feed nor discharge; the vapor at the top of the tower condenses and is completely recycled back into the tower. During operation, the material is first added to the tower; once the liquid level at the bottom of the tower reaches a certain level, full reflux operation is initiated in order to determine the normal operating conditions. Once the operation stabilizes and the quality of the material is satisfactory, it can be extracted.
Full reflux operation generally refers to no product being taken from the top of the tower.
1. Full reflux means that there is no feed nor discharge; the vapor at the top of the tower condenses and is completely recycled back into the tower. During operation, the material is first added to the tower; once the liquid level at the bottom of the tower reaches a certain level, full reflux operation is initiated in order to determine the normal operating conditions. Once the operation stabilizes and the quality of the material is satisfactory, it can be extracted. 2. Under full reflux conditions, each tray achieves maximum separation efficiency; therefore, this is the operating condition used for rapid heating up of the tower and during startup adjustments. However, if the heating power is increased, the separation load on the tray increases, the operating line moves closer to the equilibrium line, which results in a poorer separation effect and a lower purity at the top of the tower.
During full reflux, no feed is added and no product is taken out; at this point the separation efficiency of the tower is at its highest. Full reflux is generally used during startup or when the system deviates from its normal operating conditions, in order to establish equilibrium in the shortest possible time.
What about the tower bottom? 4# fengdingwen
When driving the process, feeding is first carried out at the bottom of the tower; after heating to achieve full reflux, the residual liquid begins to be extracted, and then it is withdrawn in amounts that increase gradually depending on the specific separation ratio. In the event of any abnormalities, stop feeding and extraction, allowing the gas phase to condense and flow back to the bottom of the tower, waiting to resume operation by increasing the temperature.
During full reflux operation, no feed is added to the tower nor is any product taken out. Under normal circumstances, when the tower parameters are unstable and exhibit large fluctuations, full reflux is used for adjustment; it is also employed during temperature increase or decrease operations when starting up or shutting down the plant.
Full reflux means neither feeding nor extraction takes place. The bottom liquid from the tower is not withdrawn! Run full reflux for a period of time to test the product quality; once the quality is satisfactory, the product can be released. Sometimes it’s not the material that is defective – for example, the steam supply might suddenly decrease, or the material in the storage tank might run out, or the product tank might be full! Full reflux condition is required for all of them. Once it’s stabilized and products can be produced, extraction can proceed, followed by feeding in!
I’ve learned something new; everyone explained it in such detail. I don’t have anything else to add