Method for reducing wood tar in preparation process of wood vinegar

Abstract

The invention relates to a method for reducing wood tar in the preparation process of wood vinegar, which belongs to the field of wood vinegar. Aiming at the defects that since a large amount of wood tar is generated in the preparation process of the wood vinegar, and the removing process of the wood tar is complex, the refining of the wood vinegar is disadvantageous, the invention provides the method for reducing the wood tar in the preparation process of the wood vinegar. The method comprises the following steps of crushing wood into particles and then placing the particles in a fermentation tank for fermenting; laying a layer of millets below a high-temperature furnace; stacking the wood particles on the millets; spraying rice bran on an upper layer; collecting at three temperature intervals to obtain crude wood vinegar; performing reduced pressure distillation to remove water and then sealing and standing; adding a NaCl solid in the liquid for hydraulic freezing treatment and filtering; extracting the obtained wood vinegar with diethyl ether and recovering to prepare the refined wood vinegar. According to the method, the wood tar in the wood vinegar in the preparation process can be effectively removed, and the finally-prepared wood vinegar is high in purity and less in impurity; in addition, the method is simple in process and low in cost.

Description

technical field [0001] The invention relates to a method for reducing wood tar in the process of preparing wood vinegar, belonging to the field of wood vinegar. Background technique [0002] Wood vinegar is a reddish-brown liquid with a smoky smell obtained after condensation and separation of the steam and gas mixture exported from the wood distillation equipment. It is mainly acetic acid and contains alcohol, phenol, ketone, aldehyde and its derivatives, etc. mixture of substances. Because wood vinegar has the functions of killing insects, sterilizing bacteria, disinfecting soil, eliminating fecal odor, preserving freshness, promoting the growth of plants and edible fungi, it has been widely used in Japan, South Korea and other countries in recent years. [0003] Wood vinegar is mainly composed of water, methanol, formaldehyde, acetone, acetic acid, furfural, phenol and other alcohols, acids, phenols and ketone-aldehyde organic compounds. Among the organic matter, the co...

AI Technical Summary

Problems solved by technology

[0004] The technical problem mainly solved by the present invention: A large amount of wood tar will be produced in the current preparation process of wood vinegar, and the process of removing wood tar is complicated, which is not conducive to the refining of wood vinegar, and a process for preparing wood vinegar is provided. In the method of reducing wood tar, this method uses waste wood to be crushed into granules and put into the fermentation tank, and some substances are added to carry out anaerobic fermentation. A layer of millet is spread under the high-temperature furnace, and then the fermented and air-dried wood granules are piled up. On the top, spray rice bran on the upper layer, collect in 3 temperature sections of high-temperature furnace to obtain crude wood vinegar liquid, then carry out vacuum distillation to remove water, seal and stand still, add NaCl solid to the liquid after standing for hydraulic freezing treatment and filtering, the obtained wood vinegar is extracted and recovered with ether to obtain refined wood vinegar, which can effectively remove the wood tar in the wood vinegar in the preparation process of the method, and the finally obtained wood vinegar has high purity and few impurities. Moreover, the process is simple and the cost is low