Tube Failure Reason Analysis And Improvement For Radiant Section Of Primary Reformer

The reformer in ammonia plant for hydrogen transfer reaction in the reactor, composed of radiation section, transition section and convection section, is the core equipment of the ammonia plant. The company issue300000tons/520000tons of urea synthesis device put into production in1995. Due to various reasons, since putting-in-service proactively to multiple conversion tube burst accident in2008, has replaced three times in the whole conversion tube (domestic maintenance good a conversion conversion furnace tube service life can reach more than20years). A conversion furnace in high incidence of failure and failure causes a longer shutdown and resume production time, to the company has brought great economic losses. Therefore, from the analysis of a furnace for the tube bursting reasons for transformation of from each link to find defects in equipment design, manufacture, use and unreasonable place, can fundamentally solve a converter fault happens.Based on burst into tube for macroscopic analysis, chemical composition analysis, metallographic micro structure analysis, the damage measurement and calculation, and instantaneous high temperature tensile test at room temperature and lasting strength test, X-ray fluorescence spectrum analysis, on the basis of the lookup failure reasons of furnace tube burst; And through the sorting process operation data, the analysis of detonation tube during the process of operation, the simulation calculation conversion tube under the condition of different operating conditions.Through the above experiment, calculation and analysis, find out the transformation of the effective thickness of the pipe design slants small, for the furnace tube burst congenital don; Conversion tube was partial to the relatively high temperature and thermal shock damage more serious, is direct cause of the transformation of pipe burst. Proposed increase the wall thickness in the updated conversion tube, strictly controls the conversion tube components such as modification measures. And put forward the reasonable adjust every rows each burner heating rate, ensure each burner in the burner flame jet parts of the same energy, ensure that each burner is more than burner brick surface, strict control of water/carbon ratio, strictly control the residual methane content, strict export conversion tube heating and heat absorption phenomena of matching, to prevent the formation of carbon, to prevent temperature steep steep fall and shutdown frequently, and can adjust the burner damper to reduce dosage excess air operation and optimization measures.