Device and method for manufacturing dimethyl carbonate

1. A device for manufacturing dimethyl carbonate, comprising:

a reaction section comprising:

a first distillation column;

a methanol supply device connected to the first distillation column;

a carbon dioxide supply device connected to the first distillation column;

a dehydrating agent supply device connected to the first distillation column; and

a side reactor, wherein a feed nozzle of the side reactor is connected to a gas outlet of a top of the first distillation column, a discharge nozzle of the side reactor is connected to a recycle nozzle of the first distillation column, and a catalyst is disposed in the side reactor; and

a separation section comprising:

a second distillation column connected to a liquid outlet of a bottom of the first distillation column.

2. The device for manufacturing the dimethyl carbonate according to claim 1 , wherein the second distillation column is an only distillation column in the separation section.

3. The device for manufacturing the dimethyl carbonate according to claim 1 , wherein the second distillation column is only connected to the first distillation column and is not connected to other distillation columns.

4. The device for manufacturing the dimethyl carbonate according to claim 1 , wherein the recycle nozzle of the first distillation column is located between the top and the bottom of the first distillation column.

5. The device for manufacturing the dimethyl carbonate according to claim 1 , wherein

the methanol supply device is connected to a methanol feed nozzle of the first distillation column,

the carbon dioxide supply device is connected to a carbon dioxide feed nozzle of the first distillation column, and

the dehydrating agent supply device is connected to a dehydrating agent feed nozzle of the first distillation column.

6. The device for manufacturing the dimethyl carbonate according to claim 5 , wherein the methanol feed nozzle is higher than the carbon dioxide feed nozzle, and the carbon dioxide feed nozzle is higher than the dehydrating agent feed nozzle.

7. The device for manufacturing the dimethyl carbonate according to claim 5 , wherein the recycle nozzle is as high as the dehydrating agent feed nozzle.

8. The device for manufacturing the dimethyl carbonate according to claim 1 , further comprising:

a splitter connected between the gas outlet of the top of the first distillation column and the feed nozzle of the side reactor, and comprising a first splitting nozzle and a second splitting nozzle, wherein the first splitting nozzle of the splitter is connected to the feed nozzle of the side reactor.

9. The device for manufacturing the dimethyl carbonate according to claim 8 , further comprising:

a condenser connected to the second splitting nozzle of the splitter; and

a flash vessel connected to the condenser.

10. The device for manufacturing the dimethyl carbonate according to claim 9 , further comprising:

a first backflow pipeline connected between a gas outlet of the flash vessel and the first distillation column; and

a second backflow pipeline connected between a liquid outlet of the flash vessel and the first distillation column.

11. A method for manufacturing dimethyl carbonate, comprising:

making a reactant comprising methanol and carbon dioxide enter a first distillation column, wherein the methanol is provided into the first distillation column by a methanol supply device, the carbon dioxide is provided into the first distillation column by a carbon dioxide supply device, the methanol supply device is connected to the first distillation column, and the carbon dioxide supply device is connected to the first distillation column;

making the reactant in the first distillation column enter a side reactor, wherein a feed nozzle of the side reactor is connected to a gas outlet of a top of the first distillation column, a discharge nozzle of the side reactor is connected to a recycle nozzle of the first distillation column, and a catalyst is disposed in the side reactor;

conducting a main reaction in the side reactor comprising the catalyst, so as to form a first product comprising the dimethyl carbonate and water;

making a discharge material flow of the side reactor flow back to the first distillation column, wherein the discharge material flow of the side reactor comprises the first product;

conducting a dehydrating reaction in the first distillation column by using a dehydrating agent, so as to make the dehydrating agent fully react with the water in the first distillation column to form a second product, wherein the dehydrating agent is provided into the first distillation column by a dehydrating agent supply device, and the dehydrating agent supply device is connected to the first distillation column;

making a discharge material flow of a bottom of the first distillation column enter a second distillation column, wherein the discharge material flow of the bottom of the first distillation column comprises the dimethyl carbonate and the second product, and the second distillation column is connected to a liquid outlet of the bottom of the first distillation column; and

utilizing the second distillation column to separate the dimethyl carbonate in the discharge material flow of the bottom of the first distillation column from the second product.

12. The method for manufacturing the dimethyl carbonate according to claim 11 , wherein a methanol feed nozzle is higher than a carbon dioxide feed nozzle, and the carbon dioxide feed nozzle is higher than a dehydrating agent feed nozzle.

13. The method for manufacturing the dimethyl carbonate according to claim 11 , wherein the discharge material flow of the side reactor enters the first distillation column from the recycle nozzle of the first distillation column, and the recycle nozzle is as high as a dehydrating agent feed nozzle.

14. The method for manufacturing the dimethyl carbonate according to claim 11 , wherein the dehydrating agent comprises ethylene oxide, and the second product comprises ethylene glycol.

15. The method for manufacturing the dimethyl carbonate according to claim 11 , further comprising:

splitting a discharge material flow of the top of the first distillation column to form a first split material flow and a second split material flow, wherein the first split material flow and the second split material flow comprise the reactant from the first distillation column.

16. The method for manufacturing the dimethyl carbonate according to claim 15 , wherein a flow rate ratio of the first split material flow to the second split material flow is equal to or less than 30.

17. The method for manufacturing the dimethyl carbonate according to claim 15 , wherein a flow rate of the first split material flow is greater than a flow rate of the second split material flow.

18. The method for manufacturing the dimethyl carbonate according to claim 15 , wherein the first split material flow enters the side reactor, so as to make the reactant in the first distillation column enter the side reactor.

19. The method for manufacturing the dimethyl carbonate according to claim 15 , further comprising:

condensing and flashing the second split material flow to separate out a gas phase material flow comprising the carbon dioxide and a liquid phase material flow comprising the methanol.

20. The method for manufacturing the dimethyl carbonate according to claim 19 , wherein the gas phase material flow and the liquid phase material flow back to the first distillation column respectively.