气提系统的运行特性

采用清水和空气作为介质,利用实验室条件下冷态模拟气提系统。试验结果表明在通气量一定时,随着回水流量的增大,水的压差逐渐降低。当回流水量相同时,压差随着通气量的增大而升高。气含率随着表观气速的增大而增大。     

资源型重工业城市生态承载力评价

从城市生态承载力的三类变量之间的关系出发,构建城市生态承载力评价模型;并以资源型重工业城市抚顺市2000～2009年数据为基础,分析了该市的生态压力参数和生态弹性力参数的变化情况,评价了抚顺市的生态承载力水平。结果表明:抚顺市生态承载力变化分为3个阶段,平稳期(2000～2002年)、起伏期(2002～2007年)和递增期(2007～2009年);生态承载力水平由2000年的-0.311增长到2009年的-0.017,抚顺市一直处于重载状态,属于高耗损型,强不可持续发展模式,但有趋于可持续发展的趋势。     

Hydrogen generation from polyvinyl alcohol-contaminated wastewater by a process of supercritical water gasification

Gasification of polyvinyl alcohol(PVA)-contaminated wastewater in supercritical water(SCW)was investigated in a continuous flow reactor at 723-873 K,20-36 MPa and residence time of 20-60 s.The gas and liquid products were analyzed by GC/TCD,and TOC analyzer.The main gas products were H_2,CH_4,CO and CO_2.Pressure change had no significant influence on gasification efficiency. Higher temperature and longer residence time enhanced gasification efficiency,and lower temperature favored the production of H_2. The effects of KOH catalyst on gas product composition were studied,and gasification efficiency were analyzed.The TOC removal efficiency(R_(TOC)),carbon gasification ratio(R_(CG))and hydrogen gasification ratio(R_(HG))were up to 96.00%,95.92% and 126.40% at 873 K and 60 s,respectively,which suggests PVA can be completely gasified in SCW.The results indicate supercritical water gasification for hydrogen generation is a promising process for the treatment of PVA wastewater.     

The shaped blasting experimental study on damage and crack evolution of high stress coal seam

In the deep high stress coal and rock mass, the efficiency of the ordinary blasting method is constantly affected by the high pressure. This study investigates the shaped blasting technology with increased blasting efficiency, develops a mechanical model for coal crack expansion during shaped blasting, and examines the force-energy action of energy-gathering jets during coal splitting. The established model was combined with experiments and simulations to reveal the damage and evolution of cracks in coal and rock masses. Experiments demonstrate that shaped blasting can create an energy-gathering jet that causes a directional fracture in the test block. The peak of compressive strain in the energy-gathering direction is 1.12 times greater than that of ordinary blasting, and the static action period of the explosive gas is prolonged by 1.3 μs according to the stress curve. Moreover, the peak pressure strain increased 3.2 times, and the pull strain peak increased 3.92 times. The damage amount was represented by the resistivity and ultrasonic wave speed, and shaped blasting causes 1.2 and 1.5 times greater damage than ordinary blasting. The research results provide technical methods for safe and rapid penetration blasting in deep high-ground stressed coal mines.     

Improvement of integrity management for pressure vessels based on risk assessment - A natural gas separator case study

The process of oil and gas processing plant is complex, the types of pressure vessels are rich, and the functions are critical. However, the working medium is mostly untreated medium, and the hazard factors are complex, which poses a threat to the safe production of oil and gas processing plant. Based on PDCA cycle, this paper establishes a six-step links of integrity management for sustainable improvement of pressure vessels. The typical failure modes of pressure vessels are determined, and the fishbone diagram of risk factors under each failure mode is compiled. Risk quantification and classification of pressure vessels based on failure modes (RBFM) is innovatively proposed. Avoiding incalculable failure frequency index, the process quantification of failure possibility is formed according to the development of hazard factors. A failure consequence calculation model based on the leakage affected area was established. Combined with the failure probability level and risk level, the hierarchical inspection strategy for pressure vessels under different failure modes is established. Finally, the method is applied to the natural gas separator of H processing plant. The research results show that RBFM proposed in this paper can meet the requirements for rapid and accurate risk assessment of pressure vessels in oil and gas processing plant. This paper establishes a safe production barrier for the pressure vessel and improves the intrinsic safety of the equipment.