Nghi Son Refinery is one of the biggest planned oil refineries in Vietnam. It is located about 200 km (120 mi) south of Hanoi in the Tinh Gia District of Thanh Hóa Province. Nghi Son Refinery is an integrated refinery owned by Idemitsu Kosan, Kuwait Petroleum, Vietnam National Oil and Gas Group, and Mitsui Chemicals. The refinery, which started operations in 2018, has an NCI of 6.03. Nghi Son Refinery is designated for a processing capacity of 10 million tons of crude oil per year with the possibility to increase the capacity to 20 million tons.
The project consists of the foundation works of 32 steel tanks for semi-refined and refined petroleum products. The criteria that must be met for the design are to improve:
For each tank, the load during operation and hydrostatic test were given. Hydro tests load intensity varied from 181.4 to 201 kPa.
For a Tank with a diameter of more than 25 m, the tank shell is founded on a rock mound with a uniform settlement at the edge not to exceed 300 mm. For tank less than 25 m diameters, the tank shell is founded on RC ring beam and the edge settlement is limited to 150 mm. For all tanks, the differential settlement center to edge is limited to D/300, the circumferential settlement to 13 mm over 10 m, and the tilt to H/200.
The area was recently backfilled with sandy silt, 3 to 5 m thick but with a large disparity in the compaction. The natural ground geology varies from the southwest corner where a 5 m thick soft clay layer is found, to the northeast corner of the site, where this soft clay layer is progressively replaced by a medium dense sand layer. Those overlay a firm silty clay layer 5 m thick, followed by a stiff clay layer, found at a depth of 15 m below the existing platform level.
Menard Asia’s solution for this project was ground reinforcement with the Controlled Modulus Columns (CMC) technique with specialized rigs. Menard Asia has treated the total area of 225,000 linear meters of CMC with a nominal diameter of 420 mm was improved. Our commitment to excellent services has led us to perform a specific design was done for each tank as depths, grids, and meshes of the CMCs were adapted to the diameter, the load, the type of foundation, and the soil conditions.
Menard Asia has successfully completed the project and met all of the client’s expectations. This project was added to Menard Asia‘s portfolio of process and energy in the Southeast Asian region.