Method and reaction equipment for preparing dimethyl ether and olefin from methanol
The present invention relates to a method for preparing dimethyl ether from methanol which is carried out in a reaction device arranged with a plurality of catalyst bed layers connected in series, and comprises: dividing the reactant stream that contains methanol into n substreams, and feeding these different substreams into the reaction device through top feed ports or side feed ports between the catalyst bed layers of the reaction device for methanol-to-dimethyl ether reaction; wherein, the temperature T1 of the substream fed into the first catalyst bed layer is controlled within the following range: 290−50K1≤T1≤150K1 2 −271K1+397.5; where, 1>K1≥0.5, and T1 is in unit of ° C.
1. A method for preparing dimethyl ether from methanol carried out in a reaction device arranged with a plurality of catalyst bed layers connected in series, which method comprising:
dividing a reactant stream containing methanol into n substreams, n being an integer greater than 2, and feeding the n substreams into the reaction device through top feed port or side feed ports between catalyst bed layers of the reaction device to undergo a methanol-to-dimethyl ether reaction;
wherein, according to flow directions of the reactant stream, the n substreams each have a flow rate F1˜Fn, respectively, allocation proportions Ki of the reactant in the substreams are Fi/F0, F0 being the sum of F1˜Fn, i being an integer in the range of 1˜n, and n being an integer greater than 2, and
wherein the substream fed into the first catalyst bed layer has a temperature T1 that is controlled within the following range:
290−50 K 1≤ T 1≤150 K 1 2 −271 K 1+397.5
where 1>K1≥0.5, and T1 is in unit of ° C.
2. The method for preparing dimethyl ether from methanol according to claim 1 , wherein 2≤n≤8.
3. The method for preparing dimethyl ether from methanol according to claim 1 , wherein 0.95≥K1≥0.6.
4. The method for preparing dimethyl ether from methanol according to claim 1 , wherein 1>K1≥0.6.
5. The method for preparing dimethyl ether from methanol according to claim 1 , wherein the allocation proportion Ki of the reactant in the substream i
Ki
≥
(
1
-
∑
i
=
1
i
-
1
K
i
)
×
50
%
,
wherein i≠1.
6. The method for preparing dimethyl ether from methanol according to claim 1 , wherein the number of the catalyst bed layers is greater than or equal to n.
7. The method for preparing dimethyl ether from methanol according to claim 1 , wherein the reaction device comprises one or more fixed bed reactors, with said a plurality of catalyst bed layers arranged in the one or more fixed bed reactors.