The semiconductor, electroplating, metallurgy, and ceramic industries discharge high concentration fluoride containing wastewater, making fluoride pollution in natural water a global problem.Thus， Zn?Mg?Al LDO is a good adsorbent material. Under different reaction temperatures of n（Zn²⁺）/n（Mg²⁺）/n（Al³⁺）, Zn?Mg?Al LDH was synthesized by co?precipitation method, and Zn?Mg?Al?LDH was calcined at different temperatures to obtain Zn?Mg?Al?LDO. X?ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT?IR) and BET specific surface area testing methods were used to study the structure and properties of Zn?Mg?Al LDO. The adsorption experiment was conducted on 50 mL of NaF solution with an mass concentration of 20.0 mg/L to investigate the performance of Zn?Mg?Al LDO in adsorbing and removing fluoride ions. The results showed that the Zn?Mg?Al LDO prepared under the conditions of n（Zn²⁺）/n（Mg²⁺）/n（Al³⁺）=2∶1∶1, reaction temperature of 75 ℃, and calcination temperature of 400 ℃ exhibited the best adsorption and removal performance of fluoride ions, with an adsorption and removal rate of 85.39%. Zn?Mg?Al LDO has characteristic peaks of hydrotalcite, good crystal structure, and a layered structure. Zn?Mg?Al LDO is a mesoporous material with a specific surface area of 103.15 m²/g. In addition, the kinetics and adsorption mechanism of the adsorption process were also studied. The results indicate that the adsorption process follows the Langmuir adsorption isotherm and quasi second?order kinetic equation.

With the rise of electric revolution and the establishment of "carbon dioxide emission and carbon neutrality" strategy, petroleum coke has got great development in value?added applications such as lithium cathode materials and high?grade prebaked anode.However,high value?added applications of petroleum coke all have strict requirements for sulfur content of petroleum coke. The high sulfur content in petroleum coke will have a negative impact on the high value application of petroleum coke.The research status of main desulphurization technologies of petroleum coke,including solvent extraction desulfurization technology,high temperature calcination desulfurization technology,oxidation desulfurization technology, alkali metal compound desulfurization technology,hydrodesulfurization technology,microbial desulfurization technology and process intensification auxiliary desulfurization technology are summarized.It was found that the desulphurisation rate of process?enhanced assisted desulphurisation could reach 93.6%,which could reduce the sulphur mass fraction in petroleum coke from 7.57% to 0.48%. The desulfurization technology of petroleum coke should maintain the principle that the structure of petroleum coke after desulfurization is not destroyed to the greatest extent.Therefore,oxidative desulfurization coupled process enhancement assisted desulfurization should have bright prospect in industrial application of petroleum coke desulphurization.

Industrial wastewater is mainly composed of sewage and waste liquid produced in industrial production process, which has been characterized by its complex composition, wide variety, large difference and difficulty in treatment.The commonly used methods for preparation of hydrotalcite were reviewed, such as chitosan method, plasma method and agricultural waste method. Hydrotalcite materials in the adsorption process are mostly in powder, which is difficult to be recycled, and rarely used in industry applications. In view of the above problems, Fe ions can be introduced in hydrotalcite materials to generate magnetism, which is be beneficial to recovery. By developing cheaper synthetic materials, simple and fast preparation methods, stable physical and chemical properties of hydrotalcite materials, industrial applications could be achieved. The introduction of magnetic materials into hydrotalcite composites can help to recycle. With the in?depth study of hydrotalcite preparation technology, the prospect of dealing with toxic pollutants will be better.

At present,the research on the corrosion rate of the oil casing in the wellbore containing CO2/H2S is the current research hot spot in the field of corrosion and protection. In order to accurately study the corrosion situation of the oil casing and predict the corrosion rate,the weight loss method was first adopted to study the corrosion rate under different corrosion time,and the experimental results were fitted. Secondly, combining the research results of this paper with the previous research content,the Table Curve 3D software for multiple regression was used to determine the corrosion rate prediction model.The results show that the corrosion rate decreases continuously with the increase of time.The fitting of the experimental results R2 is 0.989 3,the error is small.The model established by multiple regression can accurately predict the corrosion rate and the error is within 5%,which meets the accuracy requirements,and can lay the foundation for the on⁃site oil and gas well safety evaluation.

In the middle and late stage of development of offshore heavy oil field, strong injection and strong production are mainly adopted. Under this kind of large volume of liquid scouring, the microscopic pore structure of reservoir and the efficiency of water drive oil are changed, which brings difficulty to understanding the law of water drive development in high water cut stage of oilfield. Through simulating long⁃term water flooding and scouring physical experiments, the variation law of each characteristic parameter of reservoir during the long term water flooding scouring process is studied. The results show that for high porosity and high permeability reservoirs after long⁃term water flooding, the porosity change is not obvious, permeability is obviously increased, and invalid circulation channels are easily formed. The characteristics of pore microcosmic change are obvious, the radius of pore throat increases and the seepage ability increases. With the increase of displacement ratio, the isosmotic point shifts to the right. When the water saturation is the same, the oil phase permeability increases, the water phase permeability decreases, the residual oil saturation decreases, and the oil displacement efficiency increases by nearly 10%. The research results have been used in the field test of 2 000 m3/d liquid production per well in offshore sandstone reservoirs with high water cut, which provides theoretical support for the formulation of development strategy in high water cut period of offshore oil fields.

In this paper,a detailed study of diffusion properties of n⁃dodecane over three different modified Y zeolites was conducted by ZLC (Zero⁃Lengthc⁃Column) method to investigate the influence of pore structure and acidity of zeolites on diffusion.The characterization of XRD,N2 adsorption/desorption and NH3⁃TPD showed that the crystal structure of the modified Y zeolite remained unchanged and the pore structure was similar to that of the modified Y zeolite.However,the ratio of n(Si)/n(Al) decreased,the total acid content on the surface decreased,and the distribution of acid strength also changed significantly.The results of diffusion study showed that the diffusion ability of modified Y zeolite was increased,and the diffusion coefficient of n⁃dodecane in zeolite increased and the diffusion activation energy decreased with the increase of the number of medium and strong acid sites in the sample,which contributed to the improvement of catalytic performance.

A multi-directional analysis for the application of oil shale residue in the field of chemical industry and environment and the heap abandonment present situation of the oil shale residue is proposed. It is found that there are six limitations in recycling oil shale residue in the field of environment and chemical industry, which lead to the difficulty of proper and reasonable disposal of oil shale residue. The environmental pollution caused by oil shale residue is still serious. Based on the indepth discussion of the local limit, a new idea for disposing the oil shale residue is presented, which uses the oil shale residue to prepare bulk material of large social needed, and the preparation process is simple and the secondary energy consumption is less.

The catalytic cracking performances of several propane deasphalted oil obtained in our earlier work were investigated in a fixed fluidized bed reactor at the reaction temperature of 490 ℃, catalyst to oil mass ratio of 5 (catalysts 80 g) and space velocity of 15 h ^-1. It was found that the propane deasphalting oil with the highest saturated fraction mass fraction of vacuum residuum was a good FCC feedstock. the product distribution and selectivity of the deasphalted oil from vacuum residuum blending FCC slurry oil were better than that from FCC slurry oil. But for the deasphalted oil from FCC, slurry oil had lower conversion and light oil yield, and the cracking performance was also poor.

        Since the decline in conventional oil production, the research and development of unconventional oil are very important. Tight oil has the following characteristics. First, the property of different layers of tight oil is different, and the second is the amount of fluid in the production cycle is variational. To determine the tight oil gathering and transportation scheme, the entire production cycle is divided into three stages. The two schemes of heating and water injection are analyzed by simulating and comparing their Gathering safe distance and energy-consumption. The results show that water injection is better than heat gathering and transportation technology in these two aspects. So as to ensure the normal operation of gathering system and save operating costs, we choose water injection gathering and transportation technology.

In order to evaluate the adaptability of nanometer microspheres to the Pubei Test Block, laboratory experiment study based on the nanometer microspheres profile controlling and flooding mechanism was carried out. The experimental results showed that nanometer microspheres dissolved in oilfield sewage owned a good dispersion, and its median grain diameter can meet the plugging requirement. When the solution concentration was 2 000 mg/L, nanometer microspheres hydration swelling effect was the best, and its multiple expand reached 5.7 after thirty days. The final oil recovery was raised by 10% by nanometer microspheres profile control and displacement. It was concluded that nanometer microspheres could plug the high permeability layer of nonhomogeneous formation. The experimental results can provide theoretical bases and technological support for enhance oil recovery of low permeability reservoir．

 

In order to analyze and forecast the wall erosion in a quench oil hydraulic cyclone, the liquidsolid two phase flow and erosion profile of the wall in a hydraulic cyclone was numerical simulated. The results show that the major eroded regions are the inner wall at 45°～135° azimuth of the gas inlet, the ring section under the inlet, the lower part of cone, and underflow pipe. Moreover, at the underflow pipe, the suspension was discharged rapidly from the outlet and lead to the erosion peak. Based on the simulation results, measure for improving the antierosion performance was put forward. It can provide reference for the longperiod safe operation of hydraulic cyclone.

The method for the linear system with time－varying norm－bounded uncertainties was presented to reject periodic disturbances and to track periodic reference signals with a known period effectively，which can design the low－pass filter in the repetitive controller and the output feedback controller simultaneously．The repetitive control system was converted to a time－delay system；Based on Lyapunov theory，a sufficient condition was derived in terms of a linear matrix inequality （LMI），which ensures robust stability of the time － delay system．Based on the derived condition，the problem of designing the low－pass filter and the output feedback controller was converted to a nonlinear matrix inequality problem．By using the linear matrix inequality （LMI） and cone complementarity linearization （CCL） algorithm，an iterative algorithm was presented to calculate the larger cut－off angular frequency of a low－pass filter and the corresponding output feedback controller parameters．The numerical example is presented to illustrate the validity of the proposed method．