Advances of experimental study on gas production from synthetic hydrate reservoir in China

China has entered the area of new normal economy which requires the harmonious development of energy consumption,environmental protection and economic development.Natural gas hydrate is a potential clean energy with tremendous reserve in China.The successful field test of marine hydrate exploitation in South China Sea created a new record of the longest continuous gas production from natural gas hydrate.However,the corresponding fundamental research is still urgently needed in order to narrow the gap between field test and commercial production.This paper reviewed the latest advances of experimental study on gas production from hydrate reservoir in China.The experimental apparatus for investigating the performance of hydrate dissociation in China has developed from one dimensional to two dimensional and three dimensional.In addition,well configuration developed from one tube to complicated multi-well networks to satisfy the demand of different production models.Besides,diverse testing methods have been established.The reviewed papers preliminary discussed the mechanical properties and the sediment deformation situation during the process of hydrate dissociation.However,most reported articles only consider the physical factor,the coupled mechanism of physical and chemical factor for the mechanical properties of the sediment and the sand production problem should be studied further.

Study on Factors Influencing the Reliability of the Organization Management Chain of the Large and Medium-Sized Project in the Construction Period

On the basis of analyzing the reliability of the organization’ management chain of the large and medium- sized project in the construction period, the paper studies the factors influencing the reliability of the organi-zation management chain, which, corresponding to four elements of management chain – “Management Loop”, “Management Link”, “Management Chain”, and “Management Network”, can be summarized as project main body, interface management, connection sequence and management model. The paper then re-searches on the specific influencing factors from the above-mentioned four aspects.

Research on the Contents and Indexes of Reservoir Operational Security

Reservoirs play an important role in the development of economy and society, as well as the maintenance of ecological balance. The reservoir operational security can make every function of reservoirs fully played. This paper makes a systematic analysis on the meaning of reservoir operational security and builds up a framework system of it from the perspective of organization and system. On this3 basis, the paper researches the contents and indexes of reservoir operational security from the microscopic, intermediate and macroscopic aspects. The results of this paper provide a foundation for further research on reservoir operational security management.

Identification and Calculation Method of the Financial Benefits of IT Projects for Better Financial Evaluation

To financially evaluate an IT projects is to assess its financial feasibility, while the financial benefits are the core parameters of financial evaluation of IT projects. Therefore, correctly identifying the financial benefits of IT projects is the precondition to ensure the validity of the financial evaluation. Essentially, IT projects can be divided into productive IT projects and supportive IT projects. The paper analyzes the importance of identifying the financial benefits and introduces the meaning, characteristics and classification of financial benefits of IT projects. On this basis, the paper identifies the financial benefits of both productive IT projects and supportive IT projects and emphasizes the formation and specific calculation method of the two types of IT projects. For productive IT projects and supportive IT projects, the calculation of financial benefits should employ different methods.

水合物形成显著增强海底渗漏的甲烷在深海环境的捕集效率

海底甲烷渗漏在全球范围内普遍存在,是影响海洋碳循环和气候变化的关键环节.探明海底释放气泡的演化特性、甲烷溶解及气泡表面水合物形成动力学对理解海底渗漏甲烷的最终归宿至关重要.鉴于深海进入困难,本研究结合自研高压模拟装置和深海甲烷渗漏喷口气泡捕集实验,阐明海底原位条件下的甲烷连续渗漏特性.研究结果发现,甲烷气泡在水中的传质系数随泄漏甲烷通量的增加而线性增加,一旦水合物成核,大量溶解甲烷迅速形成絮状水合物,导致溶解甲烷浓度快速降至三相平衡浓度,并与水合物生成达成动态平衡.甲烷水合物的生成减缓了释放气泡的上升速度,表明水合物的形成是阻止甲烷输运至上层水柱的重要屏障.此外,海底的上边界可作为促进水合物形成的有效封盖,进一步增强甲烷的捕获和封存效果.本研究对理解海洋甲烷渗漏、甲烷循环及指导海洋水合物安全开发具有重要意义.