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The Alxa Plateau has one of the highest frequencies of dust events in China and one of the greatest contributions to East Asian dust. We compiled climate and dust storm data for the Alxa Plateau based on observational data from ten meteorological stations from 1961 to 2005. Our analysis showed that dust storms increased during the 1960s (until 1972), decreased until the late 1990s, and then increased slightly until 2002. The occurrence of sandstorm in Alxa Plateau presented significant difference in time and space, and the number of dust storm changes in the intergeneration presented a great fluctuate: the number of dust storm changes presented a reflection under specific climatic condition. Dust storm frequency was inversely related to land desertification and land use/cover change. The continued deterioration of the underlying surface was one of the main reasons of the increasing dust storm occurrence.

Based on CFD software and two-phase theory, lag range model was adopted to calculate gas flow in the wet electrostatic precipitator. Dispersed phase model was also used to simulate gas flow and mist in the wet electrostatic precipitator. The results show that the gas flow gets homogeneous by changing the distribution plate's parameter. The droplet's diameter has great influence on the gas flow's distribution. It is good for gas flow distribution when the droplet's diameter is 50 µm.

Adsorption model, dynamic mechanism and adsorption thermodynamic property of the version resin are discussed in this study. The results shows that Freundlich equation can favorably associate with the adsorption of fluoride ion on the D401 version resin. The adsorption process of fluorine for modified is carried out according to Freundlich adsorption model. The adsorption process is control by internal diffusion. The defluoridation material has good capability of defluoridation and the adsorption process is exothermal chemical adsorption. So rising temperature will go against the adsorption.

To improve the separation efficiency of steam and gas in power plant a new type steam separator is presented. A mathematical model is established for simulating the flow field of gas flow channels in steam separator. The gas-water separating efficiency is calculated for the droplets at different particle diameter. The equations are solved by using computational fluid dynamics (CFD) method. Fibreglass filtering method is used for measuring the Separation efficiency of steam separator. The results show that structure parameters and inlet gas velocity have great influence on the separation efficiency of wave type plate separator. The separation efficiency of steam separator with hooks is higher than that without it. Plate spacing and length offer the largest opportunity to the performance improvement. The droplets removal efficiency increases with the plate spacing reduction. The turning angle must be less than 54° for a high efficiency and low pressure loss. The gas velocity within the separator should be kept below a critical velocity as well in order to avoid re-entrainment. Separation efficiency of steam separator is high when moisture content of inlet gas is less than 30 g/m3. Numerical and experimental method can predict separation efficiency of steam separator for the removal of droplets from gas. It can be directly used for the design of steam separator.

In order to improve collecting efficiency of wet electsostatic precipitation a new polar matching system is presented. Based on Gauss Theorem and image charge method the mathematical model is established for calculating electric field intensity distribution of the new polar matching system. The results show that the electric field intensity gets homogeneous at the polar plate when polar space is at suitable value. The electric field intensity of the new polar matching system meets Gauss Theorem well at arbitrary section. The structural characteristics of electric polar is affected by many factors, such as: geometrical parameters, dust concentration distribution and applied voltage. The new polar matching system has the advantage of even electric field intensity when the electric polars and discharge nozzle-electrodes are on small distance. The calculated results accord with the actual distribution law of electrostatic precipitator. It can be directly used for the design of wet electrostatic precipitator.

In order to measure aerosol in gas of electronic and accurate manufacturing industry, a new method on measuring dust content with high precision by using superfine and high purity fiberglass is presented. As Fiberglass has the advantage of small diameter and high porosity, dust in gas will be intercepted completely by the fiberglass when the gas flows through the sampling tube filled with fiberglass. Dust content in gas can be calculated on condition that volume of gas flowing through the sampling pipe at unit time is measured. Collected efficiency increases with fiberglass filling thickness, filling ratio and single fiber collected efficiency while decreases with fiber diameter. Collected efficiency should be more than 99.5% if diameter of fiberglass is selected at 3 μm. The best temperature for baking fiberglass tube is 110 °C. The best baking time is 6 h and cooling time to constant weight must be more than 4 h. Purity of the fiberglass has great influence on its stability. For the fiberglass with a purity of 99.5%, Weight loss is less than 0.1 mg for six hours in the oven. It can be seen from the comparison experiment of fiberglass filtering method, sampling gravimetric method and optical scattering method. The fiberglass filtering method is not affected by ambient and gas temperature. The error of fiberglass filtering method is about 0.1% of the sampling gravimetric method and 1% of the optical scattering method.

A new method on measuring moisture content in gas with high accuracy is presented. Fibreglass is filled in a filter tube fixed in the sampling pipe. Mist of gas will be intercepted by the fibreglass when the gas flows through the sampling tube filled with fibreglass. Moisture content in gas can be calculated on condition that volume of gas flowing through the sampling pipe at unit time is measured. Collected efficiency increases with fibreglass filling ratio, filling thickness and single fibre collected efficiency while decreases with fibre diameter. Collected efficiency should be more than 99% if suitable diameter fibreglass is selected. The cooling time in the exsiccator must be more than 20 minutes. Purity of the fibreglass has great influence on its stability. For the fibreglass with a purity of 99.5%, Weight loss is 0.1 mg for seven hours in the oven. It can be seen from the comparison experiment of filter method, absorption method and LDV method. Fibreglass filter method has high accuracy, good repeatability and stability. The measuring results are not affected by ambient and gas temperature.

In order to separate droplets from the steam, a new type steam separator with high efficiency in power plant is presented. An experimental model is established for determining the structure parameters and critical velocity of steam separator. Fibreglass filtering method is used for measuring the Separation efficiency of steam separator. The results show that separation efficiency of the steam separator with collecting hooks is higher than that of without it. The plate length of the steam separator has almost no effect on the separation efficiency. The turning angle of the separator is at 54o, the plate spacing is at 20 mm and the critical velocity is at 5 m/s to improve the efficiency. The water film adhering on the plate wall will break when the gas velocity is more than the critical velocity. The separation efficiency decreases and secondary liquid entrainment increases significantly. Separation efficiency of steam separator is high when moisture content of inlet gas is less than 30 g/m3, however, it is low when moisture content of that is more than 50 g/m3. The optimum structure parameters and empirical formula of separation efficiency can be obtained from the experimental analysis. It is beneficial to the industrial design of steam separator in power plant.

A new method on dehydrating mist in gas with high efficiency is presented. Mist in gas can be dehydrated by the bent plate dehydration. Based on the model of steady flow of incompressible Newtonian fluid, the difference equations of flow and pressure field of bent plate dehydration equipment are built. Numerical Solution of vorticity, stream function and pressure are also obtained. The equations are solved by using matlab Version 6.5. The results show that the pressure loss of bent plate dehydration equipment is mostly affected by its structure parameters and inlet gas velocity. To decrease the pressure loss, length of the bent plate is at 120 mm, turning angle is less than 54o, and plate spacing is at 20~30 mm. The inlet gas velocity must be less than 6m/s because the water film on the wall of bent plate will be ruptured when it is more than the critical velocity. It can be seen that the tendency of pressure loss is uniform from the experimental results. The numerical method on solving the pressure loss of bent plate can be used for the industrial design.