METHOD FOR PRODUCING VINYL ACETATE

The present invention relates to a method for producing vinyl acetate. Provided in the present invention is a method for producing vinyl acetate by gas phase oxidization of ethylene, comprising: an optional step of preparing ethylene, a step of synthesizing vinyl acetate, and a step of refining vinyl acetate, wherein in at least one of the step of preparing ethylene, the step of synthesizing vinyl acetate and the step of refining vinyl acetate, at least one of a steam machine recompression technique, an air cooler, a plate heat exchanger, and a double shell pass tube-and-shell heat exchanger is used.

PRETREATMENT METHOD OF TUBER RAW MATERIALS

The present invention relates to a pretreatment method of tuber raw materials comprising: delivering tuber raw materials to a raw material sieving machine, and performing a sieving operation on the tuber raw materials to make the oversize materials be tuber blocks with impurities such as gravel having been removed; delivering the tuber blocks into a tuber block crusher to crush them, the undersize material being tuber powder enriching impurities such as gravel; mixing the tuber powder with a certain amount of water and liquefied enzymes in a primary liquefaction plant to perform a liquefaction operation so as to convert the starch in the tuber powder enriching impurities such as gravel into water-soluble reducing sugars such as glucose and polysaccharide; performing a solid-liquid separation on the liquefied mash obtained by the primary liquefaction operation to remove the mass of solid materials such as gravel and fibres in the liquefied mash; mixing the clear liquid discharged by the ...

METHOD AND DEVICE FOR RECOVERING ETHYLENE DURING PROCESS FOR PRODUCING VINYL ACETATE

Disclosed are a method and a device for recovering ethylene during the process for producing vinyl acetate, wherein a double solvent absorption method composed of an absorbent solution and deionized water is used: introducing an outlet stream as an absorbent solution from the upper section of the feeding plate in an acetic acid tower during the rectification stage of vinyl acetate production; delivering same to the top of the lower section of the ethylene recovery tower by a delivery pump; charging refined gas from the tower kettle of the ethylene recovery tower, with the absorbent solution contacting with the refined gas in a counter-current; sending the absorption kettle solution to the rectification stage for treatment; the gas continuing to rise to the upper section of the ethylene recovery tower and contacting with the deionized water introduced from the top of the tower in a counter-current; absorbing and removing the acetic acid therein; and discharging the residual inert gas, such ...

ANTI-CORROSIVE PROCESS AND DEVICE FOR METHYL ACETATE HYDROLYSIS AND ACETIC ACID REFINING IN POLYVINYL ALCOHOL MOTHER LIQUOR RECOVERY PROCESS

Disclosed are an anti-corrosive process and a device, which relate to methyl acetate hydrolysis and acetic acid refining in a polyvinyl alcohol mother liquor recovery process. The anti-corrosive device includes a methyl acetate concentration device, a methyl acetate dealdehyding device, a methyl acetate hydrolysis device, a hydrolysis liquid separation device, an acetic acid refining device and an isopropyl acetate recovery device. The process of methyl acetate hydrolysis and acetic acid refining mainly comprises methyl acetate concentration, methyl acetate dealdehyding, methyl acetate hydrolysis, hydrolysis liquid separation, acetic acid refining and isopropyl acetate recovery. A mass transfer unit (i.e. a packing section) is arranged at the upper part of the side sampling port of a hydrolysis tower to improve the ability of removing halogen-containing impurities; broken resins entrained in a hydrolysis liquid are filtered by adding a precise filter, which prevents the broken resins bearing ...

PRODUCTION METHOD AND EQUIPMENT FOR NEUTRAL EDIBLE BREWED ALCOHOL PRODUCTS

A production method and equipment for neutral edible brewed alcohol products. The production flow comprises: removing, by production units for performing operations such as liquefaction, fermentation and refining, ester, aldehyde and fusel impurities in crude alcohol by using a stripping-extraction integrated distillation process. A stripping gas is introduced from the bottom of an aldehyde column, and does not chemically react with the material in the aldehyde column under operating conditions, and the type of said gas is nitrogen or air; part of wastewater discharged from the bottom of a refining column is delivered to the top of the aldehyde column as washing water for refluxing.

METHOD FOR PRODUCING VINYL ACETATE

The present invention relates to a method for producing vinyl acetate, the method comprising a vinyl acetate synthesis process, a vinyl acetate refining process and a vinyl acetate and ethyl acetate separation process. An acetic acid evaporator, an oxygen mixer, a vinyl acetate synthesis reactor, a first gas separation tower, a second gas separation tower, a degassing tank, a water washing tower, an absorption tower, a desorption tower, an ethylene recovery tower, a circulating gas compressor and a recovery gas compressor are involved. The vinyl acetate refining process comprises an acetic acid tower, a crude VAC tower, a refined VAC tower, an aldehyde ester concentration tower, an acetaldehyde tower, a dehydration tower, a water phase receiving tank, an extractive distillation tower and an ethyl acetate tower. During the separation of vinyl acetate and ethyl acetate, an extractive distillation process using acetic acid as an extracting agent is used. In the present invention, by using ...

酢酸ビニル生産プロセスにおけるエチレン回収方法及び装置