Clean Separation Process of Chabocuo Saline Lake in Tibet

1 Introduction Chabocuo Lake is located in the territory of Gaize County Ali area Tibet,the altitude of the lake-surface is4505 m with a total area of 32 Km2.It is a typical sulfate type saline and rich in boron and lithium.In the natural evaporation process,several mineral sylvites cocrystallize out,thus increases the difficulties for separating and

Effects of working parameters on the performance of cyclone separator for rapeseed combine harvester based on CFD

Existing development for cyclone separation cleaning components of the rapeseed combine harvester,which employs the suspending airflow to separate the rapeseeds from the materials other than grain(MOG),has the challenge to figure out the optimal working parameters,highlighting a need for exploration of the invisible airflow based on Computational Fluid Dynamics(CFD).The airflow status was mainly affected by the air velocities of the inlet,and the outlet for the MOG.The single factor and response surface experiments were carried out.It could be found that the inlet and MOG outlet velocities affected the air velocities through the change in the air quantity.Furthermore,the mathematical model of the relationship between the air velocities inside the cyclone and the working parameters was built,and the optimal combination of working parameters was obtained by multi-objective optimization.The inlet and outlet velocities of the optimal combination were 4.25 m/s and 29.87 m/s,respectively.Under this condition,the cleaning ratio and loss ratio of the cleaning device was 94.62%and 5.39%,respectively,as validated by the field experiment.The findings provide references for the improvement of cleaning systems for rapeseed combine harvesters.

Separation and cleaning of Leymus chinensis seed threshing material based on gas-solid coupling

The aim of this study was to improve the cleaning performance of the Leymus chinensis seed threshing material separation and cleaning device,and to clarify the movement law and characteristics of the Leymus chinensis seed threshing material during the cleaning process.A numerical simulation of the separation and cleaning process of Leymus chinensis seed threshing material was performed using the computational fluid dynamics discrete element approach.According to the streamline distribution of the gas-solid coupling,the movement of Leymus chinensis seeds during the cleaning process was examined.Additionally,the average speed and quantity of Leymus chinensis seed threshing material in different separation and cleaning zones were studied over time.Meanwhile,the distribution principle of the threshing material was obtained,and a verification test of the under-sieve distribution was conducted.The test results showed that the numerical simulation was consistent with the distribution trend of the under-sieve.The cleaning performance verification test showed that the impurity content and the loss rate of the separation and cleaning device were 27.3%and 3.3%,where the test results,compared with those of the numerical simulation,showed a reduction of 1.5%and 0.8%,respectively.It is feasible to apply the theory and method of gas-solid coupling to simulate the separation and cleaning process of Leymus chinensis seeds.

Simulation and test on separating cleaning process of flax threshing material based on gas-solid coupling theory

In order to further clarify and improve the working performance of separating cleaning device of flax threshing material,and study the motion law and characteristics of components of flax threshing material,in this paper,numerical simulation was carried out on the separating cleaning process of flax threshing material based on CFD-DEM method.Simulation results showed that the components of flax threshing material were separated and cleaned under the influence of airflow field,meanwhile,variation curves of quantity and mean velocity of flax seeds in the separating cleaning system were obtained.By referring to streamline distribution of gas-solid coupling,the quantity variation law of components of flax threshing material with time was explored and their motion curves and variation tendency of average velocity were studied.Verification test results showed that the cleaning rate of separating cleaning device for flax threshing material was 92.66%with 1.58%of total separation loss.Compared with simulation results,the test results were 1.34%and 0.93%lower,showing that it is feasible to apply the gas-solid coupling theory and method to simulate the separating and cleaning operation of flax threshing material.

Clean separation technologies of rare earth resources in China

After a review on the conventional separation process of rare earths （RE）, hyperlink extraction technology was introduced and a potential process was proposed for clean separation of RE. A great amount of acid, base and water was consumed in the con- ventional RE separation process which included the procedures of raw material dissolving, extraction separation and precipitation. Therefore hyperlink extraction technology had been developed, by which the repeated consumption of acid and base could be avoided during the extraction process. And based on the theory and successfid applications of the hyperlink extraction technology, we pro- posed the integral hyperlink process in which the intermediate acid resulted in individual procedures would be recycled and reused after being treated. The proposed process would make it feasible to consume no chemicals except for oxalic acid, and so could be a promising clean separation technology with a significant reduction on consumption and emission.

Gas separation using porous cement membrane

Gas separation is a key issue in various industrial fields. Hydrogen has the potential for application in clean fuel technologies. Therefore, the separation and purification of hydrogen is an important research subject. CO2 capture and storage have important roles in ＂green chemistry＂. As an effective clean technology, gas separation using inorganic membranes has attracted much attention in the last several decades. Membrane processes have many applications in the field of gas separation. Cement is one type of inorganic material, with the advantages of a lower cost and a longer lifespan. An experimental setup has been created and improved to measure twenty different cement membranes. The purpose of this work was to investigate the influence of gas molecule properties on the material transport and to explore the influence of operating conditions and membrane composition on separation efficiency. The influences of the above parameters are determined, the best conditions and membrane type are found, it is shown that cementitious material has the ability to separate gas mixtures, and the gas transport mechanism is studied.