Sensible heat recycling method and device in xylose production process

Abstract

The invention belongs to the technical field of xylose production, and discloses a sensible heat recycling method in a xylose production process; pretreated wash water, hydrolyzate and hydrolysis residue sugar wash water are respectively flashed; the temperature of the hydrolyzate is reduced to 65 to 75DEG C after flashing, and a decoloring procedure is directly carried out; the decolored hydrolyzate enters an evaporator to be concentrated after ion exchange; and steam produced in the flashing of the pre-treated wash water, the hydrolyzate and the hydrolysis residue sugar wash water enters the evaporator as a heat source for evaporating and concentrating the hydrolyzate. The invention recycles the sensible heat carried by the pre-treated wash water, the hydrolyzate and the hydrolysis residue sugar wash water with higher temperature in the xylose production process, is mainly used for the evaporation and the concentration of the hydrolyzate, thereby greatly reducing the steam used in the concentration of the hydrolyzate and the underground water used before decoloring, reducing the emission of waste liquid, meeting the national policies of energy saving and emission reduction, and having wide application value.

Description

technical field [0001] The invention belongs to the technical field of xylose production, and specifically relates to a method for recovering sensible heat in a xylose production process, and at the same time relates to a device for recovering sensible heat in xylose production. Background technique [0002] Xylose is mainly made of corncobs, bagasse, birch and other agricultural and sideline products as raw materials. It is widely used in food , chemical industry, light industry and other industries. Since it is extracted from agricultural and sideline products, miscellaneous sugars such as six-carbon sugars (such as glucose, galactose, etc.) are also hydrolyzed while five-carbon sugars are hydrolyzed, so agricultural and sideline products such as corncobs need to be pretreated before hydrolysis, and the pretreatment wastewater needs to be discharged When entering the sewage station, the discharge temperature of the pretreated wastewater is 115°C, which will waste a lot of...

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Problems solved by technology

Since it is extracted from agricultural and sideline products, miscellaneous sugars such as six-carbon sugars (such as glucose, galactose, etc.) are also hydrolyzed while five-carbon sugars are hydrolyzed, so agricultural and sideline products such as corncobs need to be pretreated before hydrolysis, and the pretreatment wastewater needs to be discharged When entering the sewage station, the discharge temperature of the pretreated wastewater is 115°C, which will waste a lot of heat energy; after the pretreatment, it will be hydrolyzed, and the discharge temperature of the hydrolyzate will be 125°C. If it is not recycled, a large amount of heat will be lost during the process. The decolorization of the liquid into the next process requires a temperature below 75°C, which requires a large amount of groundwater to cool down; after hydrolysis, the hydrolysis slag needs to be washed with water to recover the sugar solution, and the sugar solution washing water returns to the hydrolysis step for re-hydrolysis, and the sugar solution washing water is discharged at a temperature of 120°C, a natural flash phenomenon will occur during the discharge process, and the flash gas will enter the atmosphere and cause environmental pollution

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