Regarding the PDS desulfurization issue
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In our PDS system, after the transformation, the hydrogen sulfide level is around 400 PPM, CO2 levels are around 20%, and the pressure is 1.2 MPa. During operation, the ratio of sodium bicarbonate to sodium carbonate reaches its maximum value of 10:1, with a pH value of around 7.5. How can we adjust the conditions so that the pH value of the solution can be around 8.2? Thank you for the guidance.
To adjust the pH to around 8.2, this can be achieved by adding alkaline components. In PDS desulfurization systems, sodium bicarbonate (NaHCO3) and sodium carbonate (Na2CO3) are commonly used as alkali sources. Since sodium carbonate has a stronger alkalinity, you can try reducing the ratio of sodium bicarbonate to sodium carbonate, for example from 10:1 to 5:1 or even lower, in order to increase the total alkalinity in the system and thus raise the pH value. At the same time, it is necessary to monitor the pH changes during the adjustment process to ensure that the pH value does not become too high due to excessive addition of sodium carbonate. It is recommended to make gradual adjustments and regularly monitor the pH value and the removal efficiency of hydrogen sulfide to ensure the balanced operation of the system. If possible, using an online pH meter to monitor the pH value in real time makes it easier to make adjustments. .
With such high pressure, it’s normal for carbon dioxide to be absorbed; steam can be used to heat and decompose sodium bicarbonate into sodium carbonate
The maximum ratio of sodium bicarbonate to sodium carbonate is 10:1; it may be advisable to reduce the amount of sodium bicarbonate while increasing the amount of sodium carbonate. Since the degree of hydrolysis of sodium carbonate is greater than that of sodium bicarbonate, increasing the amount of sodium carbonate can more effectively raise the pH value of the solution. However, note that the proportion adjustment should be carried out gradually, and the pH value of the solution must be monitored in real time to prevent excessive pH fluctuations from having a negative impact on the desulfurization effect.