Design of Roller mechanism and Conveyor in Sulfur granulation systems

Roller mechanism and conveyor are important components in sulfur granulation system. This paper presents the method to design roller mechanism to apply two goals: create a continuous pressure for a regular granulation on steel conveyor. There are also granulation mechanism and maintain temperature not to stuck and solidify of sulfur in the supplying pile. Moreover, this paper shows the solution to design steel conveyor and filtering system including with temperature sensor which ensure the decreasing of temperature over the length of steel bell. This will help the granulation of sulfur with the right size and shape.

Microstructural Evolution of Undercooled Ni-40wt%Pb Hypermonotectic Alloy

Microstructural evolution of bulk undercooled Ni-40wt%Pb hypermonotectic alloy was systematically investigated by using molten glass purification and superheating cycling. Within the achieved undercooling range, the microstructures were classified into three categories. When the undercooling was less than 50K, the microstructure consisted of coarse dendritic grain and interdendritic Pb lumps. Increasing undercooling to the range 100 to 198K, macrosegregation was serious. When the undercooling was up to 292K, refined granular grain with homogeneously distributed fine Pb particles on it formed. The granulation mechanism of granular grains was owing to dendritic disintegration and subsequent recrystallization.

Formation mechanism of nitrifying granules observed in an aerobic upflow fluidized bed (AUFB) reactor

The influences of trace metals in the wastewater and shear stress by aeration were particularly examined to clarify the formation mechanism of nitrifying granules in an aerobic upflow fluidized bed (AUFB) reactor. It was found that Fe added as a trace element to the inorganic wastewater accumulated at the central part of the nitrifying granules. Another result obtained was that suitable shear stress by moderate aeration (0.07-0.20 L/min/L-bed) promoted granulation. Furthermore, it was successfully demonstrated that pre-aggregation of seed sludge using hematite promoted core formation, leading to rapid production of nitrifying granules. From these results, a nitrifying granulation mechanism is proposed: 1) as a first step, nitrifying bacteria aggregate along with Fe precipitation, and then the cores of granules are formed; 2) as a second step, the aggregates grow to be spherical or elliptical in form due to multiplication of the nitrifying bacteria and moderate shear stress in the reactor, and then mature nitrifying granules are produced. Fluorescence in situ hybridization (FISH) analysis successfully visualized the change in the spatial distribution of nitrifying bacteria in the granules, which supports the proposed granulation mechanism.