东方1-1气田输气管道除水与干燥工艺设计及施工

Design and construction of dewatering and drying process of sub-sea gas pipelines in DF 1-1 gas field

在投产前对海底输气管道进行除水与干燥处理 ,可以抑制投产过程中产生水合物或防止海底输气管道腐蚀。文中对海底输气管道除水与干燥工艺所涉及的清管器设计、除水干燥方案设计、除水与干燥标准等技术问题做了总结分析 ,设计并实现了东方 1 1气田输气管道的除水、干燥及氮气惰化工艺。东方 1 1气田平台间生产管道和外输海底管道除水、干燥及氮气惰化工艺应分开实施。除水由干空气推动的清管“列车”完成 ;平台间生产管道干燥处理采用干空气干燥技术 ,而外输海底管道干燥处理采用甘醇干燥技术。除水与干燥效果表明 :聚氨酯材料制作的双向直板式清管器具有较好的耐磨性和密封性 ;干空气干燥和干燥剂干燥工艺是东方 1 1气田输气管道干燥处理的最佳选择。

Gas pipelines should be dewatered and dried before going on stream to avoid the forming of hydrate or to prevent them from corrosion. This paper summarizes and analyses the technical problems related to the pipeline pig design, process design, acceptance criteria etc for dewatering and drying sub_sea gas pipeline. The production pipeline and export pipeline were constructed in the first phase of DF 1、1 gas field development schedule. The dewatering, drying and nitrogen purging programs were designed based on the dewatering and drying requirements (acceptance criteria). The dewatering, drying and nitrogen purging were performed on the two sub_sea gas pipelines separately. Both pipelines were dewatered by a pig train propelled by dry air, while the production pipeline was dried by dry air and the export pipeline was dried by triethylene glycol swabbing. The operation results showed that the bi_directional pig with discs made of polyurethane has good wearing and sealing performances and dry air drying and chemical swabbing methods are most economically and technically feasible for sub-sea gas pipelines.