Modification of Volume Silica Analysis Method in Water Samples to Reduce Hazardous Wastewater at Badak LNG Laboratory

  • Lalang Dwiyoga Sakti Laboratory & Environment Control of Technical Department, Badak LNG, Indonesia
  • Ika Dalu Prasetyawan Laboratory & Environment Control of Technical Department, Badak LNG, Indonesia
  • Achmad Dian Nugraha Faculty of Mechanical Engineering, LNG Academy, Badak LNG, Indonesia
Keywords: Modification, Silica, UV-Vis Spectofotometry, Validation, Wastewater


Volume of hazardous wastewater generated from analysis of the Badak LNG laboratory activities was found around 1.93 tons with an average of 161 kg/month in 2018 where 27% of this total wastewater came from silica analysis activities. Hence, many efforts have been done to reduce the amount of hazardous wastewater. In this research, the silica analysis activities have been carried out using American Journal of Public Health (APHA) 4500-D Heteropoly Blue method by modification of the volume from the silica content of water samples and reagents at 75%, 50%, and 25% (or ¾, ½, and ¼) recipes. Moreover, in the testing and validation phase, the measurement of silica levels in all samples has been performed using UV-Vis spectrometer at a wavelength of 815 nm. These modifications have included parameters of linearity, precision, accuracy, limit of detection (LoD), and limit of quantitation (LoQ). It was found that the volume modification for all samples have fulfilled the required parameters from association of official analytical chemists (AOAC) in linearity, accuracy, and precision. For instance, sample with ½ recipes showed coefficient of determination (R2) of 0.9997%, an accuracy of 103.80, and precision (%RSD) value of 0.524. Indeed, LoD and LoQ values for this sample were found to be 0.004 and 0.008. Modification to the volume of ½ recipe was particularly chosen because it was produced the minimum amount of liquid waste remaining at 8.25 mL with the test Duplo analysis. These results demonstrated that silica analysis activities can be used for reduction of wastewater.


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Silica analysis method in water samples is used to determine its content in boiler feed water. This needs to be done for reduction of damage caused by the presence of silica. Analysis of silica at the Badak LNG laboratory produces amount of hazardous wastewater so that it needs to be reduced. Silica content of water samples and reagents in ½ recipe is fulfilled the requirments in production of minimum amount of liquid waste.
How to Cite
Sakti, L. D., Prasetyawan, I. D., & Nugraha, A. D. (2020). Modification of Volume Silica Analysis Method in Water Samples to Reduce Hazardous Wastewater at Badak LNG Laboratory. Journal of the Indonesian Chemical Society, 3(2), 101.