Short-process separation system for separating ionic liquid from alkylation reaction effluent

A short-process separation system for separating ionic liquid from alkylation reaction effluent, wherein the separation system comprises an alkylation reactor, an ionic liquid storage tank, a primary coalescence separator, a secondary coalescence separator, a flash tank, a low-temperature fine coalescence separator, and a fractionating tower, wherein:

• the alkylation reactor comprises at least one feed port, an effluent discharge port and an ionic liquid return port;
• the ionic liquid storage tank comprises an inlet in communication with bottom flow ports of the primary coalescence separator, the secondary coalescence separator and the low-temperature fine coalescence separator through delivery lines, and an outlet in communication with the return port of the alkylation reactor through a delivery pump;
• each of the primary coalescence separator, the secondary coalescence separator and the low-temperature fine coalescence separator comprises a liquid feed port, a bottom flow port and a top flow port, wherein the liquid feed port of the primary coalescence separator communicates with the effluent discharge port of the alkylation reactor through a delivery line;
• the top flow port of the primary coalescence separator communicates with the liquid feed port of the secondary coalescence separator through a delivery line;
• the top flow port of the secondary coalescence separator communicates with an inlet of the flash tank through a delivery line;
• the liquid feed port of the low-temperature fine coalescence separator communicates with an outlet of the flash tank through a delivery line;
• and the top flow port of the low-temperature fine coalescence separator communicates with a feed port of the fractionating tower through a delivery line;
• and
• the fractionating tower comprises at least one fractionating tower feed port and a plurality of fraction product discharge ports, wherein fraction products communicate with a plurality of product storage tanks through respective lines.