The invention discloses composition and application of a low-temperature and hydration synergistic low-heat early-strength
cement slurry system. The low-heat early-strength
cement slurry system is prepared from the following components in parts by weight: 100 parts of
oil well cement, 70-100 parts of a low-hydration-heat active cementing material, 3.2-6.3 parts of a hydrated
calcium silicate-polycarboxylic acid
ether nano composite early strength agent, 1.8-5.4 parts of a low-temperature activator, 0.7-1.3 parts of a fluid loss agent, 0.3-0.6 part of a dispersing agent, 0.2-1.0 part of a defoaming agent, 15-20 parts of hollow glass beads and 60-92 parts of water. According to the
cement slurry system, on the basis that a low-hydration-heat-activity cementing material is selected, the hydrated
calcium silicate-polycarboxylate
ether nano-composite early strength agent and the low-temperature activating agent are adopted and have a synergistic effect, and the
compressive strength of set cement in the curing period is jointly promoted; and the
cement slurry system has the characteristics of being small in hydration heat release, high in early strength and the like, and meanwhile, has the advantages of adjustable density, adjustable thickening time, good rheological property, low filter loss, short setting
waiting time and the like, is suitable for well cementation of ocean deepwater surface
layers and
hydrate layers, and lays a
solid foundation for development of ocean oil and gas resources.