Determination of Coagulant Dosage and Stirring Time in Laboratory Wastewater Pretreatment

Maria Siswi Wijayanti, Tuty Emilia Agustina, Muhammad Hatta Dahlan, Dedi Teguh


The use of chemicals in practical activities or research in the laboratory will certainly produce wastewater. Wastewater generated from the laboratory is classified as hazardous and/or toxic waste. Based on the substances contained in laboratory wastewater in terms of accumulated amount and a long period of time, wastewater will pollute the environment and will have an impact on living things around it if it is directly discharged into water bodies. The composition of laboratory waste is reactive and dangerous because it contains heavy metals Pb, Fe, and Cu as well as high Chemical Oxygen Demand (COD) and Total Suspended Solid (TSS) so it is difficult to decompose in nature. This study aimed to prepare the laboratory wastewater using the coagulation process as pretreatment. Therefore, this research prioritized the reduction of heavy metal levels of Pb, Fe, and Cu and reduced the content of COD and TSS with Alum as a coagulant. The highest degradation percentage of COD and TSS content occurred at the Coagulation Dose of 80 ppm, namely 99.79% and 99.80% respectively. Meanwhile, the highest degradation percentage of heavy metal levels of Pb, Fe, and Cu as well as the optimum COD and TSS content occurred at a stirring time of 60 minutes respectively, which were 49.48%, 58.96%, 94.09%, 99.97%, and 99.40%. It was concluded that the pretreatment of laboratory wastewater using the coagulation process could reduce the levels of Pb, Fe, and Cu metals, and the content of COD and TSS.


Altaher, H., E. Tarek, and R. Abubeah (2016). An Agricultural Waste as a Novel Coagulant Aid to Treat High Turbid Water Containing Humic Acids. Global Nest Journal, 18(2); 279–290

Angraini, N., T. E. Agustina, and F. Hadiah (2022). Pengaruh pH dalam Pengolahan Air Limbah Laboratorium Dengan Metode Adsorpsi untuk Penurunan Kadar Logam Berat Pb, Cu, dan Cd. Journal Ilmu Lingkungan, 20(2); 345–355 (in Indonesia)

Arita, S., T. E. Agustina, N. Ilmi, V. D. W. Pranajaya, and R. Gayatri (2022). Treatment of Laboratory Wastewater by Using Fenton Reagent and Combination of Coagulation-Adsorption as Pretreatment. Journal of Ecological Engineering, 23(8); 211–221

Audina, M. (2017). Pengolahan Limbah Cair Laboratorium Teknik Lingkungan dengan Koagulasi dan Adsorpsi untuk Menurunkan COD, Fe, dan Pb. Jurnal Teknologi Lingkungan Lahan Basah, 5(1); 1–10 (in Indonesia)

Aziz, N., N. Effendy, and K. T. Basuki (2017). Comparison of Poly Aluminium Chloride (pac) and Aluminium Sulphate Coagulants Efficiency in Waste Water Treatment Plant. Jurnal Inovasi Teknik Kimia, 2(1); 24–31

Butt, M. T., A. Khokar, K. Iqbal, and R. A. Khan (2013). Coagulation-flocculation Studies of Laboratory Wastewater using Different Combinations. Journal of the Chemical Society of Pakistan, 34(3); 636–640

Ignasius, D. (2014). Perbandingan Efisiensi Koagulan Poli Aluminium Khlorida dan Aluminium Sulfat dalam Menurunkan Turbiditas Air Gambut dari Kabupaten Katingan Provinsi Kalimantan Tengah. Jurnal Riset Geologi dan Pertambangan, 24(2); 13–21 (in Indonesia)

Mariana, M., A. K. HPS, E. Mistar, E. B. Yahya, T. Alfatah, M. Danish, and M. Amayreh (2021). Recent Advances in Activated Carbon Modification Techniques for Enhanced Heavy Metal Adsorption. Journal of Water Process Engineering, 43; 102221

Naceradska, J., L. Pivokonska, and M. Pivokonsky (2019). On the Importance of pH Value in Coagulation. Journal of Water Supply: Research and Technology-Aqua, 68(3); 222–230

Nurhayati, I., S. Sugito, and A. Pertiwi (2018). Pengolahan Limbah Cair Laboratorium dengan Adsorpsi dan Pre-treatment Netralisasi dan Koagulasi. Jurnal Sains and Teknologi Lingkungan, 10(2); 125–138 (in Indonesia)

Nurlina, T. A. Z., I. D. K. Gusrizal, et al. (2015). Efektivitas Penggunaan Tawas dan Karbon Aktif Pada Pengolahan Limbah Cair Industri Tahu. SEMIRATA; 690–699 (in Indonesia)

Raimon, R. and M. Said (2017). Laboratory Effluent Treatment by using Coagulant Alum Sulphate and Poly Aluminium Chloride (PAC). Indonesian Journal of Fundamental and Applied Chemistry, 2(2); 47–51

Shevchenko, A., T. Shevchenko, O. Pinchuk, S. Kunytskyi, and O. Miasoiedov (2018). Laboratory Studies of the Coagulation Process of Waste Waters of Milk Processing Enterprises by Changing the Mixing Rate. Ecology and Environmental Technology, 1(3); 24–29


Maria Siswi Wijayanti
Tuty Emilia Agustina (Primary Contact)
Muhammad Hatta Dahlan
Dedi Teguh
Wijayanti, M. S. ., Agustina, T. E., Dahlan, M. H., & Teguh, D. (2022). Determination of Coagulant Dosage and Stirring Time in Laboratory Wastewater Pretreatment. Indonesian Journal of Environmental Management and Sustainability, 6(4), 137-142.
Copyright and license info is not available

Article Details