【作者】 郑亚男；

【导师】 郑西来；

【作者基本信息】 中国海洋大学 ， 环境规划与管理， 2013， 博士

【摘要】 根据相关法律法规的规定，海上油气设施在停止生产作业后，如果没有其他用途或合理理由，必须进行废弃处置。海上退役采油平台的弃置需要综合考虑成本费用、作业安全和环境风险等因素，是一项复杂的系统工程。作为海上退役采油设施的主要弃置方案之一，平台造礁方案通过将平台废弃结构改造为人工鱼礁的方式对退役平台进行再利用。该方案不但能够节约拆除成本，降低海上作业的风险，减小对海洋生态环境的影响，同时可以使退役平台的生态功能得以充分利用，在渔业增殖和改善退役油区生态环境等方面起到了积极作用。本文首次以平台造礁工程的全部作业流程为研究对象，以构建平台造礁工程技术体系框架为研究目标，运用系统工程分析法和工作分解结构（WBS）的原理，系统地研究了平台造礁工程所涉及的资料收集、环境与设施调查、工程可行性论证、平台拆除、礁体设计与布局、鱼礁加工与投放、工程验收以及后续跟踪调查与评价等技术环节，提出了平台造礁工程的研究思路和技术路线，构建了海上退役采油平台造礁工程技术体系，并以埕岛油田海上退役平台造礁示范工程为例，通过对鱼礁投放前后示范区的海洋生态环境状况进行跟踪调查和监测，对平台造礁示范工程的适宜性、实施过程和实施效果（渔业增殖、生态修复）进行实证研究，从而为我国开展平台造礁工程实践提供技术支持和管理依据，并为国家和各级行政主管部门制定相关规范、规程和条例提供参考。本文得到的主要结论如下：(1)提出了平台造礁工程可行性论证的原则、依据与方法。对平台造礁方案的适用条件进行了分析，探讨了平台造礁论证的总体原则，提出了平台造礁工程论证的主要内容，其中包括：充分搜集平台所在海区的相关环境背景资料和平台设施的相关资料；进行现场调查监测并分析现状监测数据的可靠性和代表性；通过对各种资料整理、分析，从人工鱼礁建设对水文、地质、水质和生物资源等方面的要求来论证平台造礁工程的可行性。(2)构建了海上退役平台的人工鱼礁改造工程的技术框架和体系。对海上退役采油平台拆除工作以及平台造礁工作的整个流程进行梳理，并对每一关键技术环节进行分析和说明。平台造礁工程的主要程序包括退役平台设施的清洗、拆除，以及鱼礁礁体的布局、设计、加工和投放。(3)确定了平台造礁工程验收和后期跟踪调查评价的内容和方法。从验收条件、标准和验收内容等方面规范平台造礁工程的验收流程；从水质、沉积物、生物、流场和礁体现状等方面对平台造礁工程的环境影响进行调查监测，建立平台造礁工程的跟踪调查制度和环境影响后评估指标体系。(4)通过对埕岛油田海域水体环境和生态系统的现场调查，确定了鱼礁投放地址，并对礁址适宜性进行了评价。结果表明，埕岛油田海域的地势、地质条件，水质条件，水体流速，水深以及生态渔业条件均满足人工鱼礁的选址要求，故选择埕岛油田CB6A平台栈桥北海域作为平台造礁示范工程实施海域。(5)分析了平台造礁示范工程对该海域水质及沉积物的环境修复效应。与对照区相比，鱼礁投放区悬浮物浓度明显升高，鱼礁建设所产生的上升流可能是导致悬浮物增加的主要原因，而上升流携带底层营养盐与表层海水充分交换，增加了海水营养盐的含量（硝氮、氨氮、化学需氧量、磷酸盐、总磷等），促进各种藻类的生长从而提高了海域初级生产力。(6)研究了平台造礁示范工程对该海域生态系统和渔业资源的影响。结果表明，鱼礁群建成15个月时，礁群高度与建成2个月时的礁群高度相差不大，且礁群未发生明显倒塌，具有很好的稳定性；与对照区相比，投礁后鱼礁区浮游植物数量增加，而浮游动物和底栖生物的数量减少，这可能与鱼类对浮游动物和底栖生物的摄食有关；鱼礁区的渔业资源密度高于对照区，约为对照区的1.6倍。更多还原

【Abstract】 According to the stipulations of relevant laws and regulations, offshore oil and gasfacilities in stop production, if for no other purpose or reason, must be disposed of.Offshore oil and gas facilities disposal is a complex system engineering, which shouldtake many factors into account such as the cost, safety and environmental risk factors.As one of the main disposal scheme of decommissioning offshore oil productionfacilities, Rigs-to-Reefs project transforms the decommissioning platform as artificialfish reef by retaining the offshore platform structure retired in whole or in part andlaying the artificial reef in the surrounding area. This project can not only save thedemolition costs, reduce the risk on operation and the effect on marine ecologicalenvironment, but also can make the ecological function of decommissioning platformbe fully utilized. The retained structures and the artificial reefs can play positive rolesin fishery resources multiplication and ecological environment improvement.Since the USA Minerals Management Service first proposed in1983"Rigs-to-Reefs" project, The researchers from European and America have maderesearch on the Rigs-to-Reefs project from different angle such as the environmental,economic, legal and dismantling technology and so on. But these studies are notinvolved the key techniques in each stage of Rigs-to-Reefs project as a whole from thepoint of systematic induction and generalization, and have not formed a completetechnical system. In China, the Rigs-to-Reefs f project has not been popularized.There are only a few researchers who gave a brief introduction to the Rigs-to-Reefs.The study on the technical system is blank.In2010, China Petrochemical Shengli Oilfield Branch Company carried out the"Rigs-to-Reefs" demonstration project in Chengdao Oilfield for the first time in China.Based on the actual research on demonstration project, this paper takes the entireoperation process of Rigs-to-Reefs project as the research object, and building a framework of Rigs-to-Reefs project technical system as the research purpose. On thebasis of system engineering analysis method, Work Breakdown Structure （WBS）principle and reference related research literature and other relevant laws andregulations framework provisions, this thesis proposes the research mentality and thetechnical route of Rigs-to-Reefs project, and systematically analyzed the technicallinks included in the Rigs-to-Reefs project such as data collection, environment andfacilities investigation, engineering feasibility, platform demolition, the reef designand layout, reef processing and delivery, project approval and follow-up survey andevaluation, etc. The mainly studies and results achieved are following:（1） The foundation, principle and key links for feasibility demonstration ofRigs-to-Reefs project are proposed in this paper. Through analyzing the applicableconditions of Rigs-to-Reefs project, the general principles are discussed, based onwhich the demonstration process is standardized. In order to demonstrate thefeasibility of the Rigs-to-Reefs project, the environmental information of theplatform’s sea area should be fully collected, sorted, and analysed at first, and then thesuitability of the Rigs-to-Reefs project should be evaluated according to somestandards and methods.（2） This paper constructs the technical framework and technical system ofRigs-to-Reefs Project. The whole process including the disposal of decommissioningoffshore oil platform and the utilize the abandoned platform structures for artificialreefs is straightened out, and then every key technology link was analyzed andillustrated.（3） The contents and steps of the tracking survey evaluation after the Rigs-to-Reefsproject are determined. When the Rigs-to-Reefs project ends, the acceptance of workis needed, and the ecological environment effect of the project should be investigatedand evaluated. For those which do not reach the original expectation, it should beadjusted in a timely manner after seeking the reason from marine environment, overalldesign, design of reefs, and other aspects.（4） Through the study of marine water environment and ecological system, the reef address is determined and the reef site suitability evaluation is evaluated. The resultsshows that the terrain, geological conditions, water quality conditions, the water flowvelocity, water depth and the ecological fishery conditions of the sea area whichChengdao Oilfield locates all meet the site selection requirements. Therefore, wechoose the north sea area of CB6A platform in Chengdao Oilfield as the location ofRigs-to-Reefs project.（5） This paper analyses the environmental effect of the Rigs-to-Reefs project on thesea water and sediment in the area. Compared with the control area, the suspendedsolids concentration of fish reef zones increase significantly which maybe owing tothe upwelling caused by fish reef construction. The upwelling brings the nutrientexchange between the underlying and the surface water, increasing the nutrientcontents(NH₄⁺-N, NO₃--N, COD, PO₄³⁺, TP, etc.) of the sea water and improving themarine primary productivity.（6） The effect of the Rigs-to-Reefs project on the ecosystems and fisheriesresources of this sea area is studied. The results shows that the reef group height ofwhich it is constructed after15months is similar with that after2months. The reefgroup do not collapse, showing a good stability. Compared with the control area, thephytoplankton quantity increases after the reefs were placed, while the quantity ofplanktonic and benthic animals decrease. This may be related to the fish ingestion ofPlanktonic and benthic animals. The density of fishery resources in reef area is higherthan the control area, and the former is about1.6times of the latter.更多还原