In the completions of deep-water wells with the presence of gas, it may be necessary to use gas hydrate inhibitors, in these cases the design of the completion fluid usually focuses on determining the concentration of hydrate inhibitor and meeting the criteria of maximum pressure and minimum crystallization temperature of the brines. The effect of the hydrate inhibitor on the PVT behavior of the mixture is usually ignored, the changes in the compressibility of the mixture (brine - hydrate inhibitor) may be different from that of the brine without a hydrate inhibitor, and could place the pressure hydrostatic outside the mud window geopressure, compromising the stability of the well.
To solve the problem that represents the design of the completion fluid for wells in deep water environments, in this work a methodology of design of the completion fluid is proposed that integrates compliance with the requirements of hydrate inhibition, crystallization, and stability hydraulics. The methodology guides the design of the completion fluid, until it meets all the requirements of the well. The proposed methodology addresses deep-water environments, however, it can be applied to HPHT wells or in all cases where PVT changes occur in completion fluids.