Xi Ping Huang

Research on Controllable Synthesis of Magnesium Carbonate Tri-Hydrate

In order to promote the comprehensive utilization of salt lake brine resources, magnesium carbonate tri-hydrate (MgCO3·3H2O) was synthetized by low-temperature hydrothermal technique using purified MgCl2-rich brine and ammonium hydrogen carbonate solution as raw materials, the orthogonal experimental as method. The morphology could be tuned by changing the operating parameters. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the structures and morphologies of the products. The results show that the optimum conditions are as follows : reaction temperature is 40-50°C, n (Mg2+):n (HCO3-)=1:2.2, pH value is 8.8-9.0, stirring speed is 130 r/min, aging time is 3h, reaction time is 70 min. Magnesium carbonate tri-hydrate synthetized is one-dimensional acicular with good settling performance. Average aspect ratio could up to 29.60.

Progress of High Purity Magnesium Oxide Preparation

The research status of high purity magnesium oxide preparation is introduced in this paper. First, process for preparing high purity MgO is summarized, the global and domestic production status of high purity magnesia is also described. Finally, the problems and disadvantages of current MgO preparation methods are concluded, also development direction of preparation method basing on brine utilization in the production of MgO is put forward.

Research Progress of High Quality Silicon Steel Magnesium Oxide

Silicon steel magnesium oxide is a coating material used for preparing oriented silicon steel. In this paper, The preparation methods of silicon steel magnesium oxide and research progress of high quality silicon steel magnesium oxide preparation technology were introduced. The use of abundant brine resources in the preparation of silicon steel magnesium oxide was prospected.

Study of Establishment and Operation of Salt-Gradient Solar Pond

In this paper, it was presented that the establishment and experimental investigation of a salt-gradient solar pond. The solar pond was filled with salty water to form three zones (e.g., upper convective zone, non-convective zone and lower convective zone) accordingly with different methods of saline injection. Parameters like salinity and temperature were measured and recorded daily at various locations in the salt-gradient solar pond. The results showed that solar pond collected and stored solar energy for a long period of time can be possible by controlling the thickness and salinity of salt gradient layer of the solar pond.

Study on the Salt Gradient Maintenance of Solar Pond

In this paper, we established a simulated mini solar pond, and carried out a series of experiments to maintain the salt gradient solar pond. Meanwhile, the salinity variation of the lower convective zone (LCZ) of solar pond was investigated. Research results showed that by means of injecting saturated brine into the bottom of solar pond periodically, the salt gradients of solar pond could maintain relatively stable during a long time.

Study of Crystallizer 3D Modelling Based on Fluent and its Application in Production of Gypsum

The research status of crystallization process and crystallizer of gypsum is introduced in this paper. Progress in 3D mathematical simulation of crystallizer based on Fluent is summarized, and the application of the 3D model in the construction and optimization analysis is also described. Furthermore, the prospect of Fluent applied in the design and optimization of gypsum crystallizer is introduced. Finally, the potential and prospect of Fluent basing on the 3D mathematical simulation of crystallizer in the production of gypsum is put forward.

Research Progress of Solar Pond Technology

The discovery and heat-collecting principle of solar pond was introduced. Meanwhile, the research development of solar pond technology in experimental study and theoretical study were summarized. The development of solar pond technology in applied study also was described. Finally, the developing tendency of the solar pond technology was prospected.

Effect of Water Distribution Ways on the Operation of Solar Pond

An experimental study on the evolution of the salinity profiles in the salinity gradient solar ponds was executed using a small model pond. The body of the simulated pond is a cylindrical plastic tank, with 50 cm height and 45 cm diameter. The salinity gradient was established in the laboratory tank by using the salinity redistribution technique. The measurements were taken during a period of 20 days of experimentation. This period of time allowed the existence of salt diffusion from the storage zone to the surface. Results obtained from this study show that when the ratio of brine/water is 1/1, the salinity gradient layer can sustain a longer time and the lower convective zone is thicker, which is benefit to store solar energy.

Synthesis of Magnesium Borate (Mg2B2O5) Whisker by Flux Method

Magnesium borate (Mg2B2O5) whisker was successfully synthesized by high temperature flux method using Magnesium chloride, boric acid, sodium hydroxide and sodium chloride as raw materials.The as-prepared product was characterized by X-Ray Diffraction (XRD), Scanning Electron Microscopy(SEM), Transmission Electron Microscope (TEM) and X-Ray Photoelectron Spectrometry (XPS). The results showed that the as-prepared sample had triclinic structure and consisted of whisker-like particles with an average diameter about 1.25 μm and length up to 40μm. XPS results confirmed that the molar ratio of each atom agreed with the stoichiometric composition of Mg2B2O5. The growth mechanism was briefly discussed.