Patent ID: 7402424

Claim:
A method of high-temperature and high-pressure measurement of pH of a fluid, the method comprising: a. inputting an amount of dye solution into a dye chamber; b. inputting an amount of water into a fluid sample chamber; c. adjusting the pressure of the dye solution with a first pressure regulating means and adjusting the pressure of the water with a second pressure regulating means to a measurement pressure; d. measuring a spectrum of the water; e. displacing the water with a fluid sample, while ensuring that the second pressure does not drop below the measurement pressure; f. measuring a spectrum of the fluid sample; g. inputting a desired amount of the dye solution into the fluid sample chamber, while ensuring that the first pressure does not drop below the measurement pressure; and h. measuring a spectrum of the dye solution and the fluid sample mixture; i. determining the pH of the fluid sample using the measured spectrum.