Judul: Settling Rate Modelling in Secondary Clarifier Based on Contact Stabilization's Detention Time Variation for Leachate Treatment
Abstrak: 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.
Keyword: air lindi, compression, hindered, laju pengendapan, pemodelan, leachate, compression, hindered, settling velocity, modelling

Judul: Estimation of Leachate Effluent  Quality in Stabilization Contact Unit Based on Biokinetic Parameters stabilization  process
Abstrak: Kandungan polutan organik yang terkandung pada air lindi melebihi baku mutu berdasarkan Permen LHK Nomor P.59/MENLHK/Setjen/Kum.1/7/2016 tentang Baku Mutu Air Lindi Bagi Usaha dan/atau Kegiatan Tempat Pemrosesan Akhir Sampah. Pengolahan biologis kontak stabilisasi dirancang untuk mendegradasi kandungan polutan organik air lindi. Penelitian ini bertujuan mengestimasi efluen air lindi berdasarkan parameter biokinetika unit stabilisasi. Prosedur penelitian skala laboratorium dilakukan dalam empat tahap, antara lain tahap persiapan, tahap pengambilan sampel, tahap pengujian reaktor pada kondisi tidak tunak, dan tahap analisis laboratorium. Persamaan umum biokinetika yang digunakan antara lain Monod, Contois, Blackman, dan Chen-Hashimoto. Berdasarkan hasil perhitungan dan uji validasi, parameter biokinetika terpilih diperoleh melalui persamaan Blackman dengan nilai Ke, Y, μmax, Ks sebesar 2,05 hari-1 ; 32,88 mgMLVSS/mgCOD; 0,57 hari-1 ; 24,38 mg/L. Konsentrasi efluen rata rata yang diperoleh melalui persamaan Blackman berdasarkan variasi waktu detensi 4 – 6 jam berturut-turut sebesar 208,46 ± 23,35 mg/L; 173,39 ± 54,03 mg/L; 146,83 ± 30,46 mg/L., The content of organic pollutants contained in leachate exceeds the quality standard based on the Minister of Environment and Forestry Regulation No. P.59/Menlhk/Setjen/Kum.1/7/2016 concerning Leachate Water Quality Standards for Business and/or Activities of Waste Final Processing Sites. The stabilizing contact biological treatment is designed to degrade the organic pollutant content of leachate. This study aims to estimate the leachate effluent based on the biokinetic parameters of the stabilization unit. The laboratory-scale research procedure is carried out in four stages, including the preparation stage, the sampling stage, the reactor testing stage under unsteady-state conditions, and the laboratory analysis stage. The general biokinetic equations used include Monod, Contois, Blackman, and Chen-Hashimoto. Based on the results of calculations and validation tests, the selected biokinetic parameters were obtained through the Blackman equation with the values of Ke, Y, μmax, Ks of 2.05 day-1 ; 32.88 mgMLVSS/mgCOD; 0.57 day-1 ; 24.38 mg/L. The average effluent concentration obtained through the Blackman equation based on the variation of detention time 4 – 6 hours in a row was 208.46 ± 23.35 mg/L; 173.39 ± 54.03 mg/L; 146.83 ± 30.46 mg/L.
Keyword: Air lindi, biokinetika, kontak stabilisasi, Biokinetics, leachate, stabilization contact

Judul: Kisaran Inang Dan Uji Serologi Virus Penyebab Mosaik Kuning Pada Tanaman Kaboca (Cucurbita maxima Duch.)
Abstrak: Kaboca (Cucurbita maxima Duch.) merupakan salah satu tanaman sayur yang berasal dari Jepang yang berarti labu, dan banyak ditaham di daerah Segunung, Cipanas, Jawa Barat. Tanaman ini sangat berpotensi untuk dikembangkan sebagai salah satu sayuran ekspor Indonesia. Hal ini didukung oleh segi potensi ekonomi, yaitu harganya relatif mahal dan mampu berproduksi tin&ggi karena dapat menghasilkan bunga betina yang banyak.
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