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It is proven that there is a macro dust belt over the Northern Hemisphere, extending from northern Africa to East Asia. The dust emissions from the dust belt can reach up to around 2100 Tg/year. The Saharan desert is the largest contributor to the dust belt, accounting for about 50-60% of the total global dust. Our study indicates that Saharan dust can be transported to the upper troposphere in East Asia, contributing a substantial dust 22.88-44.94 Tg/year. It provides a new perspective on the important role of Saharan dust over East Asia. Climate variability has a significant impact on these regions, so that, it is needed to know how the aerosol particles change in the region in the context of global warming. Aiming to obtain the vertical distribution of dust aerosol and clouds, we have initiated a ground-based lidar network along the dust belt since 2018. Dust events were observed by the ground-based lidar at Tazhong station in 2021 and Ruoqiang station in 2020. We characterized the vertical distribution of these dust events. In the future, the lidar network is expected to establish 15 sites before 2024, extending from China to Northern Africa. The ground-based lidar system in the lidar network is a multi-wavelength Mie-Raman polarization lidar developed by Lanzhou University for continuously detecting water vapor, aerosols and clouds. To better assess the climate effect of dust aerosol over the region, other advanced instruments, such as sun-photometer, microwave radiometers, PM10/PM2.5 monitoring device, automatic meteorological station etc., are installed at each lidar site. The lidar network will provide continuous observational data of aerosols and clouds, which helps to better understand climate change in the region.

This paper intends to take power system planning as the main module, while considering the requirements and constraints of natural gas network and transportation network construction and use the energy hub model to analyse the energy transmission and transformation relationship between different networks, to realize the power system, natural gas network, and transportation. Integrated energy system planning for the network. To verify the effectiveness of the proposed PMIES planning method, an improved Garver test system is used for simulation. The system includes a 7-node natural gas network system and a 6-node electric test system. We optimized and analysed the simulated system for model research.

In view of the problem that water cut rises quickly in conglomerate reservoirs with high water cut, based on the variation law of reservoir water injection and liquid production characteristics, a method for determining the maximum liquid production scale in conglomerate reservoirs with high water cut is established by using reservoir engineering and field statistics.Considering the maximum liquid production capacity at the well end, the maximum injection capacity at the well end and the injecting-production ratio limit to keep the formation energy, a method to determine the maximum liquid production scale in conglomerate reservoir is established to keep the formation energy sufficient.This method ensures that the injection and production ends of the reservoir are coordinated and matched, and the formation energy is sufficient, so that the reservoir development keeps a benign cycle.The research method and conclusion have important reference value and significance for theoretical research and practical application of ultra-high water cut oilfield development.

The special sedimentary environments of conglomerate reservoir lead to pore structure characteristics of complex modal, and the reservoir seepage system is mainly in the “sparse reticular-non reticular” flow pattern. As a result, the study on microscopic seepage mechanism of water flooding and polymer flooding and their differences becomes the complex part and key to enhance oil recovery. In this paper, the actual core samples from conglomerate reservoir in Karamay oilfield are selected as research objects to explore microscopic seepage mechanisms of water flooding and polymer flooding for hydrophilic rock as well as lipophilic rock by applying the Computed Tomography (CT) scanning technology. After that, the final oil recovery models of conglomerate reservoir are established in two displacement methods based on the influence analysis of oil displacement efficiency. Experimental results show that the seepage mechanisms of water flooding and polymer flooding for hydrophilic rock are all mainly “crawling” displacement along the rock surface while the weak lipophilic rocks are all mainly “inrushing” displacement along pore central. Due to the different seepage mechanisms among the water flooding and the polymer flooding, the residual oil remains in hydrophilic rock after water flooding process is mainly distributed in fine throats and pore interchange. These residual oil are cut into small droplets under the influence of polymer solution with stronger shearing drag effect. Then, those small droplets pass well through narrow throats and move forward along with the polymer solution flow, which makes enhancing oil recovery to be possible. The residual oil in weak lipophilic rock after water flooding mainly distributed on the rock particle surface and formed oil film and fine pore-throat. The polymer solution with stronger shear stress makes these oil films to carry away from particle surface in two ways such as bridge connection and forming oil silk. Because of the essential attributes differences between polymer solution and injection water solution, the impact of Complex Modal Pore Structure (CMPS) on the polymer solution displacement and seepage is much smaller than on water flooding solution. Therefore, for the two types of conglomerate rocks with different wettability, the pore structure is the main controlling factor of water flooding efficiency, while reservoir properties oil saturation, and other factors have smaller influence on flooding efficiency although the polymer flooding efficiency has a good correlation with remaining oil saturation after water flooding. Based on the analysis on oil displacement efficiency factors, the parameters of water flooding index and remaining oil saturation after water flooding are used to establish respectively calculation models of oil recovery in water flooding stage and polymer flooding stage for conglomerate reservoir. These models are able to calculate the oil recovery values of this area controlled by single well control, and further to determine the oil recovery of whole reservoir in different displacement stages by leveraging interpolation simulation methods, thereby providing more accurate geological parameters for the fine design of displacement oil program.