Modularization for ground engineering construction in the Anyue Gasfield, Sichuan Basin, with the designed annual gas processing capacity of six billion m3

In the Anyue Gasfield, Sichuan Basin, the Lower Cambrian Longwangmiao Fm gas reservoir in Moxi Block has enormous natural gas reserves, and it is a typical three-high (high temperature, high pressure, and high flow rate) sour gas field. Its ground engineering project (with the designed gas processing capacity of 60 × 108 m3/a) is characterized by high processing rate of each unit, complex process control, large construction load, restricted construction site and tight schedule. Based on the traditional engineering construction mode, however, it is difficult to complete the project design and construction within 16 months. In view of this, the design concept of unit large-scale modularization was introduced to implement “normalized design, scale purchase, factory-like prefabrication and modularized construction” and develop the modularization technology of large-scale surface engineering construction. This modularization technology is performed as follows. First, the modularized units are laid out reasonably according to the technological process. Second, the layout of modularized units is usually superimposed in the multi-layer framework. Third, those equipments with the same or similar operational modes, medium properties, functional characteristics and installation requirements are concentrated in the pattern of a module. Fourth, escape passageway is specially set up. Fifth, room for installation, maintenance and repair of large equipments is reserved. And sixth, transportation and hoisting requirements of modules are taken into consideration sufficiently. This technology is contributive to the improvement of design quality, effective shortening of design period, reduction of field working load, decrease of safety management risk of on-site installation, increase of production efficiency, conservation of land occupation and diminishment of construction investment. It plays a reference role in the modularized construction of surface engineering of similar large projects.