Evaluation on the Use of Turbidimetry as an Indirect Measurement of Total Suspended Solids

Abstract

The Leyte Geothermal Production Field has been operating for more than two decades. Drilling has used to maintain and further increase the productivity of the field. This strategy is tempered by allowing sufficient provisions and protocols so as not to damage nearby wells. Monitoring the total suspended solids (TSS) of nearby monitor wells during drilling serves as a pre-emptive strike against further damaging wells from influx of cooler drilling fluids or cement materials. Standard gravimetric TSS analysis requires a minimum of two hours to finish. Qualitative (visual) analysis also becomes limited with the rise of the use of polymers in the drilling fluids that are indiscernible to the naked eye. Thus, there is a need to look for faster analytical methods that would also give comparable data. This study shows the correlation of turbidity and total suspended solids (TSS) in geothermal samples taken from Tongonan and Mahanagdong wells in the Leyte Geothermal Production Field. The results show that turbidity and TSS of the geothermal samples have a fair linearity with an r2=0.5861. Using the correlation, dubbed as the final model, to calculate for TSS based on the turbidity readings, the results yielded an acceptable Mean Average Precision Error (MAPE) or 45%. The final model will be used to estimate TSS values from turbidity readings during interference monitoring to provide ample time to mitigate any interference from nearby production wells.