Process for recovering ethanol in gruffs

Abstract

The invention relates to a method for reclaiming ethanol in medicine residue. The method comprises the steps of reclaiming through dry process and reclaiming through wet process; firstly, the reclaiming through the dry process is carried out: a steam valve which leads to an extraction tank is opened; steam is led to the bottom of the medicine residue for water steam distillation and ethanol reclaiming; the distilled ethanol passes through a cooling system and enters a storage tank; after a concentration of the distilled ethanol is equal to or slightly lower than a concentration of the used and extracted ethanol by ten percent, heating is stopped; then, the reclaiming through the wet process is carried out: drinking water or steam condensation water at a temperature of between 50 and 80 DEG C is added from the bottom of the extraction tank till immerging the surface of the medicine residue; the steam valve which leads to a jacket is opened; the residual ethanol is reclaimed by adopting peripheral heating and boiling maintenance under the condition of normal atmosphere or micro-vacuum; and the distilled ethanol passes through the cooling system and enters the storage tank; when the concentration of the distilled ethanol is between 2 and 10 percent, the heating is stopped and the ethanol reclaiming is finished. The method has high reclaiming rate, realizes the repeated use and the maximum reclaiming of the ethanol, changes waste into valuable and quite meets the need of national energy conversation and emission reduction. Compared with the prior reclaiming method, the method reduces the reclaiming time by 3 to 6 hours, thereby reducing the reclaiming cost.

Description

technical field [0001] The invention relates to a method for recovering ethanol in medicinal dregs in the field of traditional Chinese medicine pharmacy. Background technique [0002] At present, in the production process of traditional Chinese medicine preparations, ethanol is mostly used as the extraction solvent for the active ingredients of Chinese medicinal materials, and the recovery of ethanol after ethanol extraction is a very important process. The reason is that if the ethanol recovery method is improper, not only will the ethanol recovery cost be higher, the ethanol loss will be serious, but also there will be great hidden dangers to environmental protection and social security. At present, ethanol recovery from medicinal dregs is mainly carried out by adding water and cooking to recover the ethanol completely and reduce the loss of ethanol. However, due to the addition of water in the recovery process, water and ethanol form an azeotropic liquid, and the recover...

AI Technical Summary

Problems solved by technology

However, due to the addition of water in the recovery process, water and ethanol form an azeotropic liquid, and the recovery time reaches 6-8 hours. The recovered ethanol has a low concentration and is difficult to use directly. It is still necessary to re-use the atmospheric rectification tower for redistillation. In order to increase the concentration of ethanol, the cost of ethanol use remains high, and the loss also increases