Prediction of clog time of amorphous silica in the pipes of the wells from Los Humeros geothermal field – A new geochemical model along with a computational algorithm

Abstract

The primary objective of this article is to introduce a physicochemical model along with a computational algorithm that is valuable for quantifying the occurrence of silica scaling and fouling within geothermal production wells. This model utilizes two-phase flow parameters, temperature and pressure profiles, as well as brine composition to forecast the timing of production pipe constriction caused by amorphous silica deposition over time. The model is applicable to systems with temperatures ranging from 270°C to 305°C, vapor pressures ranging from 55 to 93 bars, and enthalpies ranging from 1189 kJ/kg to 1400 kJ/kg. The predictive model was calibrated using data gathered from six distinct wells within the Los Humeros geothermal field in Mexico, and subsequently, it was applied to forecast outcomes in two additional wells. When the conditions of temperature, pressure, and enthalpy remain relatively constant throughout the production process, the model developed in this study accurately predicts the times at which a certain percentage of pipe sealing occurs in wells with high volumetric fractions of liquid (εl>0.5) and temperatures between 270°C and 305°C. The prediction error is less than 3%.