真菌酶对影响稠油黏度的大分子组分的降解特性及降解机理研究

The continuing high demand of global energy and progressive depletion of conventional oil reserves has led to increased emphasis on efficient exploitation of heavy oil and bitumen reserves to meet energy demand. Although the resources of unconventional oils in the world are more than twice those of conventional light crude oil, their high viscosity or even immobility make it more difficult and expensive to extract, and many current technologies cannot satisfy their efficient production even with high oil prices. Microbial enhanced oil recovery technologies are becoming accepted worldwide as cost-effective and great potential sound solutions for oil production. On the basis of previous studies that fungal extracellular enzymes can be used to degrade paraffin, aromatic, resin, and asphaltene fractions of crude oil, thereby reducing oil viscosity, this study proposed the use of fungi in the form of fungal extracellular enzymes to degrade heavy oil, improve heavy oil recovery efficiency, and investigate enzymatic degradation charateristics and mechanism of heavy components. Under the project, it’s planned to determine enzyme activity (e.g., dehydrogenase, oxygenase, laccase, peroxidase) using ultraviolet spectrophotometry or fluorescence method, to evaluate the degradation efficiency of heavy oil and four fractions (saturates, aromatics, resin, and asphaltene) and viscosity of heavy oil using microbiological methods and chemical analysis methods to explore the efficiency of enzyme treatments on the heavy components and degradation selectivity, to measure the structure and chemical composition of four fractions, metabolites, acid and gas using chemical method and FT-IR to reveal degradation mechanism of heavy components. The results of the study will provide theoretical and scientific foundation for revelation of degradation mechanism for heavy components and improvement of microbe viscosity reduction.

随着石油资源需求的不断增长以及轻质原油的不断消耗，世界范围内的稠油开发活动日趋活跃。但由于稠油富含胶质、沥青质等重质组分，黏度高、流动性差，开采困难。利用微生物开采稠油极具潜力且经济有效。本项目在前期研究工作基础之上，即真菌胞外酶可有效降解轻质原油中的重质组分及固体石蜡，进而改善其理化性质，降低原油黏度这一现象为切入点，提出将真菌酶引入到稠油微生物开采技术中，探究其降解性能及降解机理。本项目拟采用紫外分光光度法或荧光法测定酶的活性；通过微生物学方法和化学分析方法，测定稠油中饱和烃、芳香烃、胶质和沥青质的含量变化及稠油黏度等指标，探究真菌酶对稠油中大分子组分的降解效果及酶对烃类物质的降解选择性；通过测定稠油中四种组分的结构变化、代谢产物以及酸、气体等组分，揭示蜡质、胶质及沥青质的降解机理。研究结果将为揭示稠油中大分子组分的降解机理及微生物降黏技术的提高和完善提供理论基础和科学依据。

稠油开采是扩大石油资源利用的重要途径，但由于稠油富含胶质、沥青质等重质组分，黏度高、流动性差，开采困难。利用微生物开采稠油极具潜力且经济有效。本项目在前期研究工作基础之上，将真菌酶引入到稠油微生物开采技术中，探究其降解性能及降解机理。研究发现，真菌胞外酶具有较强的脱氢酶和加氧酶活性，能够有效降解稠油及稠油中的饱和烃、芳香烃、胶质及沥青质等重质组分，经GC-MS分析显示这四种组分在酶解后，发生了明显的转移和转化，且在降解过程中产生大量气体和有机酸，除此之外，真菌酶能够有效降低稠油黏度，最高降黏率达66.33%，真菌酶具有一定的稠油驱动能力，室内模拟试验显示，驱油率最高为8.48%。研究结果将为揭示真菌酶对稠油中大分子组分的降解能力、降解机理及微生物降黏技术的提高和完善提供理论基础和科学依据。