Combined Bed Methanol to Gasoline Process

Abstract

A process for preparing gasoline from methanol by means of a combined bed comprises the following process steps: preheating raw material methanol by means of a preheater (18); feeding the preheated raw material methanol into an evaporator (19) and completely gasifying the raw material methanol; enabling the gasified raw material methanol and a recycling gas enter into a combined constant temperature reactor (21) from a mixed-gas inlet pipe, discharging the raw material methanol and the recycling gas from a mixed-gas outlet pipe, and feeding a catalyst from a feeding port to carry out a reaction; discharging the product from the discharging port, and then feeding the product into a condenser (22) in two paths, condensing the product, and enabling the product to enter a gas-liquid separator (20); outputting the separated gas as circulating gas, and outputting liquid into an oil-water separator (23) for separation, so as to obtain finished oil and water. The process overcomes the defects of high operation pressure, high feeding temperature, large recirculating ratio, much more generated invalid low-temperature heat, inconvenience in reutilization, and inconvenience in large-scale industrial production.

Description

technical field [0001] The invention relates to the field of chemical process flow, in particular to a combined bed methanol-to-gasoline process. Background technique [0002] Combined bed methanol to gasoline is a strong exothermic reaction, and there are currently reactors including fixed bed reactors, fluidized bed reactors and multi-tubular reactors. The disadvantages of fixed-bed reactors in use are: the released heat cannot be well removed from the reactor, resulting in runaway temperatures, and it is necessary to use a circulating gas that is more than 7 times larger than the feed methanol for temperature control, which seriously affects the quality of the reaction products. The stability and the service life of the catalyst shorten the regeneration period of the catalyst, and the process and equipment are complex, high energy consumption, and high investment; the disadvantages of the fluidized bed reactor in use are: the catalyst entrained in the reaction product nee...

AI Technical Summary

Problems solved by technology

The disadvantages of fixed-bed reactors in use are: the released heat cannot be well removed from the reactor, resulting in runaway temperatures, and it is necessary to use a circulating gas that is more than 7 times larger than the feed methanol for temperature control, which seriously affects the quality of the reaction products. The stability and the service life of the catalyst shorten the regeneration period of the catalyst, and the process and equipment are complex, high energy consumption, and high investment; the disadvantages of the fluidized bed reactor in use are: the catalyst entrained in the reaction product needs to be removed Separation increases the investment cost of the equipment; because the catalyst in the fluidized bed is moving, it will cause the catalyst to be broken, the powder catalyst is not easy to separate from the reaction product, and the catalyst loss will increase; the multi-tubular reactor is in use The disadvantages are: ordinary tubes are used. Due to the strong exothermic reaction, the temperature difference between the tube side and the shell side is too large. Only materials with large specific heat capacity can be used to remove heat, but the heat cannot meet the requirements of continuous feeding. Raw materials are heated; if there is less heat removed, the bed will overheat and affect the catalyst. Only increase the number of heat exchange tubes, but increasing the heat exchange tubes will greatly increase the cost of equipment; because there is no gas distributor at the feed of multi-tube reactors, Catalyst regeneration will be incomplete

None of these three reactors alone can completely satisfy the relatively efficient use of catalyst in the reactor.

[0003] The disadvantages of the prior art are: the operating pressure of the feed port is above 2.2MPa, the feeding temperature is high (requires above 300°C), and the reaction temperature can only enter the reactor; the fixed bed circulation ratio is above 7:1, in order to ensure the reaction conditions and the performance of different catalysts, there are various reactors in the process of exothermic reaction, and the process is complicated; the volume requirement of the equipment is large, and it is not convenient to realize large-scale industrial production; the equipment investment is large, the production cost is high, and the refined oil The yield is not high

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