Optimization and improvement system of dinitration circuit-to-mononitration circuit pipe in methylbenzene nitrification procedure in toluene diisocynate production

The invention discloses an optimization and improvement system of a dinitration circuit-to-mononitration circuit pipe in a methylbenzene nitrification procedure in toluene diisocynate production. Thesystem comprises a dinitration separator S13A13, wherein the dinitration separator S13A13 is fixedly connected with a first pipeline arranged horizontally; a valve is fixedly connected with the middleof the first pipeline; the other end of the first pipeline is fixedly connected with a second pipeline arranged vertically; a third pipeline arranged horizontally fixedly connected between the valveand the dinitration separator S13A13; the other end of the third pipeline is fixedly connected with a fourth pipeline arranged vertically; an interface controller is fixedly connected with the upper end of the fourth pipeline; and the other end of the interface controller is fixedly connected with a fifth pipeline arranged horizontally. The system ensures waste acid from a dinitration circuit cansmoothly flow into a mononit