Pemodelan Kecepatan Pengendapan pada Unit Sedimentasi Sekunder Berdasarkan Variasi Waktu Detensi Kontak Stabilisasi Air Lindi

Abstract

Bulking menjadi permasalahan pada pengolahan limbah cair. Analisis terkait karakteristik sedimentasi penting dilakukan untuk menghindari fenomena tersebut, terutama sedimentasi dengan karakteristik hindered dan compression settling. Pemodelan laju pengendapan hindered dan compression settling dilakukan untuk mengetahui metode terbaik dalam analisis kecepatan pengendapan sedimen air lindi menggunakan tiga metode antara lain Kynch, Robert’s derivation, serta Dick and Vesilind. Hydraulic Retention Time (HRT) unit kontak divariasikan menjadi 1 jam, 2 jam, dan 3 jam, sedangkan HRT unit stabilisasi divariasikan menjadi 4 jam, 5 jam, dan 6 jam. Hasil penelitian menunjukkan bahwa metode Kynch dan Robert’s derivation memiliki nilai Akaike Information Criterion (AIC) terendah pada variasi 1 dan 3, sedangkan metode Dick and Vesilind memiliki nilai AIC terendah pada variasi 2 dan 4. Nilai AIC pada variasi 5 untuk kedua metode bernilai sama. Pemodelan menggunakan metode Kynch, Robert’s derivation, maupun Dick and Vesilind tergolong valid pada pengamatan sedimen air lindi. Namun, perolehan nilai AIC pada kedua metode di tiap variasi tidak memiliki perbedaan nilai yang signifikan sehingga metode Dick and Vesilind bisa digunakan sebagai pemodelan terbaik pada tiap variasi .

Bulking becomes a problem in wastewater treatment. It is important to analyze sedimentation characteristics to avoid this phenomenon, especially sedimentation with hindered and compression settling characteristics. The modeling of hindered and compression settling rates was carried out to find out the best method for analyzing the sedimentation rate of leachate using three methods, namely Kynch, Robert's derivation, and Dick and Vesilind. Hydraulic Retention Time (HRT) of contact unit was varied into 1 hour, 2 hours, and 3 hours, while HRT of stabilization unit was varied into 4 hours, 5 hours, and 6 hours. The results showed that the Kynch and Robert's derivation methods had the lowest AIC values in variations 1 and 3, while the Dick and Vesilind method had the lowest AIC values in variations 2 and 4. The AIC values in variation 5 for both methods were the same. Modeling using the Kynch, Robert's derivation, and Dick and Vesilind methods are valid for leachate sediment observations. However, the acquisition of AIC values in the two methods in each variation did not have a significant difference in value so that the Dick and Vesilind method could be used as the best modeling for each variation.