Parametric Study of Sulfur Trioxide Decomposer in a Small-Scale Test Loop Facility

A High Temperature Gas Cooled Reactor （HTGR） with an outlet coolant temperature of 950 ℃ is considered as an efficient reactor to couple with the thermo-chemical Sulfur Iodine （SI） cycle for a hydrogen production. The test loop was installed in the Korea Atomic Energy Research Institute （KAERI） facility to confirm the integrity of the sulfur trioxide decomposer, one of the key components in the test loop, under HTGR operating conditions. In this paper, the simulation using Aspen plus, a chemical process simulator, was made to evaluate the performance of a sulfur trioxide decomposer. The simulation indicated that at least 10 kW heat needs to be supplied to the sulfur trioxide decomposer in the test loop when the sulfuric acid flowrate is 0.5 kg/min. The simulation flowsheet was obtained and the material balance around the sulfur trioxide decomposer was determined in case of 10 kW heat input and 0.5 kg/min flowrate of liquid sulfuric acid. The parametric study was carried out for sulfur trioxide decomposer. It indicated that the moles of sulfur dioxide produced at the decomposer increases as the operating temperature increases and is decreasing as the operating pressure becomes higher at a given temperature. The parametric study also indicated water vapor removal out of the decomposer is a less effective method to increase the sulfur trioxide conversion ratio.

Analyses of Reaction Mechanisms among Different Sulfonation Reagents and m-Diphenylamine and Crystal Structures of the Formed Compounds

In the traditional process, m-phenylenediamine reacts with fuming sulfuric acid at high temperature to get intermediates, and then after dehydration occurs intramolecular rearrangement to get 2,4-diaminobenzenesulfonic acid. Traditional methods need to consume a lot of fuming sulfuric acid or concentrated sulfuric acid, resulting in high industrial large-scale production cost, more waste, and posing a serious environmental pollution risk. In this thesis, three different sulfonation reagents were used for the sulfonation reaction of m-phenylenediamine, and the reaction mechanisms and crystal structures of the three pathways were investigated. The three routes are: 1) one-step synthesis of monosulfonated compound 1 from raw material and sulfur trioxide (SO3);2) rapid reaction of raw material and chlorosulfonic acid to synthesize bisulfonated compound 2;3) direct eutectic crystallization of raw material and ordinary sulfuric acid to obtain compound 3. The crystal structure of the compounds synthesized by three paths was analyzed by X-ray single crystal diffraction, and compound 1 was characterized by NMR, Fourier infrared spectra, UV-visible spectrum and Mass spectrometry. The one-step synthesis of SO3 as a sulfonation reagent has the advantages of mild reaction conditions, simple operation and low cost.

Corrosion of Basic Refractories for Glass Tanks Using Petrol Coke and Countermeasures

Replacing heavy oil with petrol coke can greatly reduce the cost of glass production,but obviously shorten the service life of refractories used in the regenerator checker body of glass tanks.To prolong the service life of the regenerator checker body,the slag chemical composition and alkali-sulfur ratio of glass tanks after using petrol coke and the damage mechanism of the residual magnesia bricks in the regenerator checker body were studied,as well as the corrosion resistance of three magnesia based bricks(direct bonded magnesia chrome bricks,fused rebonded magnesia chrome bricks,and fused rebonded high-purity magnesium aluminate spinel bricks).On this basis,a series of targeted countermeasures were adopted to optimize the configuration of refractories,significantly improving the service life of checker bricks and meeting the requirements of glass industry development.