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Yang, Jingsi

Publications and source records attributed to Yang, Jingsi.

14 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Development of Spouting Bed Reactor for Reduction of Hematite to Magnetite (Final Report)

This project was designed to leverage both past and current technology development efforts and utilize the expertise of the National Energy Technology Laboratory (NETL) in a collaborative effort with SIOX for the development of a spouting bed reactor to produce magnetite from very fine hematite waste. More specifically, the effort involved the conversion of a steel manufacturing byproduct, iron oxide hematite (Fe 2 O 3 ), and reduces it chemically into a salable magnetite product applicable to a number of markets. SIOX previously operated a magnetite batch production facility based on a rotary kiln reactor process. Unfortunately, that process was both costly and inefficient, making it difficult to achieve desired economies, purity, and throughput levels. NETL’s technology, developed in this work, replaced the batch inefficient rotary kiln with a continuous spouting bed reactor capable of producing synthetic magnetite products. In the project, NETL was to develop the spouting bed for the SIOX application and SIOX was to construct and operate a fully integrated pilot scale demonstration plant. NETL successfully completed its tasks, but SIOX due to financial issues was not able to complete their tasks. They have chosen not to participate in this final report so for their tasks a short summary of NETL’s knowledge of their efforts is included.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Effects of Riser Diameter on Solids Holdup and Particle Velocity Profiles in Circulating Fluidized Bed Riser Systems

Tests were performed in a 0.1-m diameter small circulating fluidized bed (SCFB) and 0.3 m diameter cold flow circulating fluidized bed (CFCFB) riser systems located at the National Energy Technology Laboratory (NETL) to study the effects of riser diameter on the riser hydrodynamics. These tests were performed at solids circulation rates of G s = 20 and 75 kg/m 2 s and superficial gas velocities of U g = 5.8 and 6.5 m/s using high-density polyethylene (HDPE) pellets with a density of 0.863 g/cm 3 , particle size range of 600–1400 µm (with a Sauter mean diameter of 871 µm, placing them in the Geldart B classification). Comparisons of riser axial pressure and solids fraction profiles, radial particle velocity profiles, and radial profiles of higher statistical moments and select chaos analysis parameters were considered. The results showed that for a given U g and G s , the smaller diameter riser exhibited characteristics associated with more dilute solids flow than that observed in the larger diameter riser. Additionally, the larger diameter riser exhibited a downward flow of solids near the wall under all test conditions, whereas the smaller diameter riser data exhibited little or no indications of solids downflow near the wall. Overall, these findings suggest that, from an industrial standpoint, a direct scaleup of small-scale tests cannot readily be accomplished as the solids holdup and the solids velocity profiles in small units (those normally tested in the laboratory) are not similar to those of large units and the performance of large units can therefore not be predicted from small-scale tests.

42 ENGINEERING↗
DOE OSTI2020

Hydrodynamic Characterization of a Shallow Rectangular Spouted Bed Using Bed Pressure Signals and Image Processing Methods

To support the design of spouted bed reactors, experiments are performed in a rectangular spouted bed to measure the peak pressure drop (Δ P max ) and the internal and external spouting velocities ( U is and U es ). Four particle types spanning under Geldart D and B are used. U is and U es are measured from bed pressure drop and expansion ratio profiles, respectively, with the U es / U is ratio of each particle type obtained. Additionally, correlations predicting the Δ P max of Geldart D and B particles are developed by reviewing published correlations and investigating the nozzle effect. Good prediction is achieved with a slope of 0.997 and an adjusted R 2 of 0.998 in a 95% confidence interval. U es is predicted through correlations developed by adding effects of d p / D i and H 0 in the Mathur–Gishler equation. The calculated U es agrees well with the experimental data, achieving a slope of 0.998 and an adjusted R 2 of 0.998 in a 95% confidence interval.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Applying image processing methods to study hydrodynamic characteristics in a rectangular spouted bed

This paper presents systematic image processing methods for investigating hydrodynamic characteristics in a rectangular spouted bed (30.2 mm × 101.6 mm). The objective is to provide a non-intrusive technique to determine the bed expansion ratio, the jet height and the fountain height due to their significant influence on the hydrodynamics of the entire bed. A high-speed video camera is used in the experiment with Geldart D particles as the bed material. After the image acquisition, image denoising, thresholding, logical and mask operations are applied correspondingly for the boundary discrimination, based on which an algorithm has been developed to determine the bed height successfully. With the discriminated boundary, morphological operations viz. erosion and dilation have been used to accurately determine the jet height and the fountain height. The feasibility of the technique is proven through profiles of bed expansion ratio, jet height and fountain height under three initial bed heights (0.0762 m, 0.102 m, and 0.127 m) for two different nozzle sizes (0.0096 m and 0.0127 m). Depending on the determination of the hydrodynamic characteristics, different flow regimes can be distinguished comprehensively through profiles of the bed expansion ratio and bed pressure drop in combination with the standard deviation of jet/fountain height. The proposed flow regime discrimination verifies the feasibility and effectiveness of the image processing methods in assessing the solids behavior in the spouted beds. Results about the variation of the jet height and the fountain height under current operating conditions as determined by the new technique are also discussed.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2018

Structural and biochemical characterization of the yeast HD domain containing protein YGK1 reveals a metal-dependent nucleoside 5-monophosphatase

Highlights: • The yeast HD domain proteins YGK1 and YB92 as 5-nucleotidases were determined. • Extensive conserved residues in the cleft were identified essential for YGK1 activity. • YGK1 dimeric core represents a characteristic of the HD family of 5-nucleotidase. • Flexible loops might confer selectivity for nucleotide. HD-domain is a conserved domain, with the signature of histidine and aspartic (HD) residues doublets. HD-domain proteins may possess nucleotidase and phosphodiesterase activities, and they play important roles in signaling and nucleotide metabolism. In yeast, HD-domain proteins with nucleotidase activity remained unexplored. Here, we biochemically and structurally characterized two HD domain proteins YGK1 (YGL101W) and YB92 (YBR242W) from Saccharomyces cerevisiae as nucleoside 5-monophosphatases, with substrate preference for deoxyribonucleoside 5-monophosphatase over ribonucleoside 5-monophosphatase. By determining the crystal structure of YGK1, we unveiled that YGK1 structure resembled as the crystal structure of YfbR from E. coli. Size-exclusion chromatography and crosslinking studies suggested that YGK1 and YB92 existed in the form of a dimer, respectively, which were consistent with structural observation of YGK1. Site-directed mutagenesis demonstrated that more extensive conserved residues near the divalent metal coordinating active site were essential for YGK1 activity than previous suggested. The metal coordinating His89 and Asp90, and the neighboring conserved Glu93, Glu114 and Glu145 were individually critical for catalysis. In addition, alignments suggested that three flexible loops with hydrophobic residues might be implicated in substrate selectivity to nucleoside moiety. Together, our comparative structural and mutational studies suggested that YGK1 and YB92 functioned as 5-nucleotidases in S. cerevisiae.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Estimation of Minimum Spouting Velocity in a Rectangular Spouted Bed

Here, a study was conducted to explore the effects of static bed height, nozzle diameter, cone angle, and particle properties on the minimum spouting velocity in a 4 in × 1 in rectangular spouted bed. Tests were conducted with various solids materials (including 871 μm HPDE pellets, 3.2 mm nylon beads, 707 μm glass beads, and 1.5 mm alumina spheres), two gas inlet nozzle diameters, and two cone angles. Experimentally obtained minimum spouting velocities were compared to existing published correlations developed for cylindrical spouted beds. In each case, it was determined that the existing correlations did not adequately predict the minimum spouting velocity for a rectangular spouted bed. A new correlation is proposed.

36 MATERIALS SCIENCE↗