Reactor capable of reducing back mixing for preparing alkenes by dehydrogenation of alkanes and preparation method

Abstract

The invention relates to reaction apparatus for catalytic dehydrogenation of alkanes. The reaction apparatus comprises a reaction section and a reactor sedimentation section; the reactor sedimentationsection is positioned on the upper part of the reaction section; the diameter of the reaction section is gradually decreased from top to bottom; a catalyst regeneration tube aslant stretches into thereaction section, and the outlet end of the catalyst regeneration slant tube is positioned at the lower part of the reaction section; and a feeding distribution device is positioned below the outletend of the catalyst regeneration slant tube in the reaction section. The reactants and the catalyst in the reactor flow concurrently upwards, so that the uniformity of the temperature distribution inthe reactor can be effectively improved, local high temperature can be avoided, and then the thermal reaction is reduced. In addition, the diameter of the reactor is gradually decreased along the flowing direction of the fluid, and the secondary conversion of the alkenes caused by back mixing is reduced, so that the yield and the selectivity of alkenes are improved. A high-temperature regeneratoris directly sprayed into the bottom of the dense-phase bed of the reactor, so that rapid mixing of the high-temperature catalyst with the catalyst in the reactor is facilitated, and local high temperature in the bed layer is avoided. The dense-phase fluidized catalyst is beneficial to the ending of the transmission of free radicals, so that the thermal reaction is reduced, and the selectivity of preparing alkenes by the dehydrogenation of alkanes is improved.

Description

technical field [0001] The invention relates to a circulating fluidized bed reactor, in particular to a circulating fluidized bed alkane dehydrogenation reaction device, and more specifically to an alkane dehydrogenation reaction device capable of reducing back-mixing. Background technique [0002] Olefins and diolefins (ethylene, propylene, butene, isobutylene, isoprene and butadiene, etc.) in synthetic resins, plastics, high-octane gasoline blending components (methyl tert-butyl ether, methyl tert-amyl Ethers and alkylated oils) and other high value-added products are widely used. In addition to these olefins, steam cracking of hydrocarbons (such as steam cracking of ethane, steam cracking of naphtha), catalytic cracking of olefins (such as Superflex technology), catalytic cracking of heavy oil (such as TMP, DCC technology) and catalytic pyrolysis of heavy oil (such as CPP technology) and other processes, the catalytic dehydrogenation of alkanes is also an important techn...

AI Technical Summary

Problems solved by technology

CN 201510003556.0 Aiming at the problem that the reaction regeneration system is too complicated in the scheme proposed by ZL 201110123675.1, a simplified circulating fluidized bed scheme is proposed, and the regenerator is improved to ensure that the fuel can be fully burned and fully exchange heat with the catalyst

Images