Nano nickel sulfide catalysts (NSCs) were successfully prepared for residue slurry-phase hydrocracking, which were synthesized by precipitation reaction in cetyltrimethylammonium bromide (CTAB) or mixed-surfactant (CTAB and Tween-80)/1-butanol/toluene/water reverse microemulsion in the presence of NiCl 2 as the nickel resource and (NH 4 ) 2 S as the sulfiding reagent. The prepared catalysts were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Experimental data revealed that both the kind and content of surfactants play a significant role in the morphology and size of NSCs. The particle size and crystallinity of NSC increased by thermal sulfiding at 300°C in Karamay vacuum gas oil (KLVGO). Optical micrographs showed that NSCs could be well-dispersed in Karamay atmospheric residue (KLAR) without obvious aggregation. On the basis of the lower yields of gas, atmospheric residue (AR), and coke, the NSCs showed higher catalytic activity than a conventional water/oil-soluble Ni catalyst. NSCs had excellent coke suppression performance (coke yield is less than 0.65 wt %), and the produced coke mainly dispersed in liquid products. With the decrease of NSC particle size, the coke suppression performance enhanced and the size of toluene-insoluble fraction in liquid products (TI-LP) decreased. NSCs provided location for coke generation and deposition during the slurry-phase hydrocracking process. The crystal form of NSCs dispersed in the TI-LP was Ni 3 S 2 , which was confirmed by XRD analysis.

The longitudinal and transverse wave velocity of sedimentary rock of coal measures is systematically analyzed by ultrasonic-time dynamic testing. The parameters of dynamic elasticity are calculated. Static mechanical parameters of the rocks are synchronously tested. The qualitative and quantitative relationships between the dynamic and static elasticity parameters, and between the physical and mechanical parameters and acoustic wave velocity of the rocks are established. The research results show that there is a good positive correlativity between dynamic modulus of elasticity and the longitudinal or transverse wave velocity, but there is no such positive correlativity between dynamic Poisson's ratio of the rocks and its longitudinal or transverse wave velocity. The dynamic elastic modulus of the rocks is higher than its static elastic modulus, while the dynamic Poisson's ratio is lower than its static Poisson's ratio, and there is a linear correlativity between them. The relationships between density of the rock, uniaxial compressive strength, tensile strength and the longitudinal or transverse wave velocity are also the positive correlativity, which are best fitted by quadratic function, exponential function and linear function, respectively.

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The use of a vertical well pattern results in productivity deficiency and poor development effect when developing buried hill reservoirs with complex properties. In this work, experiments are conducted to determine the best pattern for complex structure wells in buried hill reservoirs. Discretization is employed in an experimental method that uses unit cubic rocks with a size of 5 cm × 5 cm × 5 cm. The rocks are bonded in a spotty or reticular design to form a macroscopic model. Based on water flooding similarity criteria of fractured reservoir, an experimental model similar to a quarter of a five-spot unit in an actual reservoir is designed and manufactured. By selectively plugging wells in the model, various well patterns are established. Simulation results indicate that the vertical-vertical well pattern exhibits the fastest water breakthrough, fastest increase in water cut, and lowest recovery under the same pressure difference and well spacing. The horizontal-horizontal well pattern has the slowest water cut increase and the highest final oil recovery. For fishbone wells, this pattern facilitates an ideal development effect when the percolation direction is perpendicular to the plane determined by the mother bore and branch. When liquid rate, water cut, and recovery are considered, the horizontal-horizontal well pattern is recommended when conditions allow.

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