No abstract

Correlation between the BOD/COD ratio and Partition coefficient of octanol/ water (Pow) on a single organic substance shows that the Pow value is directly proportional to the toxicity level and inversely proportional to BOD/COD ratio. This research examined the correlation to a mixture of organic substances. The objective is to obtain a varied range of substances, as well as determining the quality of wastewater discharging to fresh waters. Need for analysis of organic substances used as antiseptics during the Covid-19 pandemic. In addition, organic substances from the organophosphate pesticide class, diazinon, were used. BOD5, COD, Pow, and LC50-96h toxicity tests using Daphnia magna were used. Six types of the mixture of organic substances included diazinon-formaldehyde-isopropyl alcohol, ethanol-oxalic acid-formaldehyde, isopropyl alcohol-glycerol-lactose, acetic acid-isopropyl alcohol-formaldehyde, sucrose-glycerol-acetic acid, and oxalic acid-formaldehyde-diazinon, with 3 different concentrations of 10, 100, and 1000 mg/L, three repetitions. The lowest BOD/COD ratio (<0.2) and the highest Pow value (>4) are found in diazinon-formaldehyde-IPA. Its toxicity in D. magna also showed the lowest LC-50 (11.82 mg/L). Whereas, sucrose-glycerol-acetic acid had the highest BOD/COD ratio (>0.7) and lowest Pow (<0.7) with the highest LC- 50 (567.88 mg/L). Other organic substances mixtures have characteristics in the range of these mixtures. Pow variability and the BOD/COD ratio have a negative correlation. A mixture of organic matter is more biodegradable making it has a higher tendency to dissolve in water.

Microplastic (MP) has been a new emerging contaminant in the municipal water supply. A water treatment process is a key to producing high-quality and safe drinking water. The performance of a conventional drinking water treatment plant (CDWTP) to remove MPs is questionable. This research aimed to investigate the performance of 2 CD-WTPs in East Java in removing MPs. Full-stage treatment in two CDWTPs consisted of intake, pre-sedimentation, coagulation-flocculation, sedimentation, sand filter, and disinfection units. Five L water samples were collected with a grab sampling technique in the sampling points of intake and outlet of each water treatment unit. MP abundance and characteristics in each sample were determined using a Sunshine SZM-45T-B1 stereomicroscope and a Nicolet i10 FTIR spectrophotometer. Total MP removal efficiencies in CDWTPs I and II were 66 and 62%, respectively. The coagulation-flocculation unit performed the highest MP removal efficiencies (56%). The MP with 1-350 μm size achieved lower removal efficiencies (33-53%) than that with 351-<5,000 μm size (53-76%). The removal efficiencies of fiber, fragment, and film in the CDWTPs were 61-65%; 86-100%; and 100%, respectively.

Abstrak-Pemerintah Kabupaten Sidoarjo membangun TPST Lingkar Timur yang beroperasi sejak 12 Desember 2015. TPST tersebut melayani sebagian besar sampah di Kecamatan Sidoarjo, Candi, dan Buduran dengan total 6.510 KK. Kondisi yang ada di TPST ini masih belum sesuai dengan Permen PU nomor 03/PRT/M/2013, karena belum memiliki zona penyangga, sistem pengendalian pencemaran lingkungan, dan instalasi pengolahan. Selain itu, belum ada tempat untuk menyimpan sampah terpilah. Penelitian ini bertujuan untuk mengukur kuantitas dan komposisi sampah yang diolah di TPST, mengevaluasi kondisi eksisting pengelolaan sampah di TPST Lingkar Timur, dan merencanakan ulang desain dan optimasi pengelolaan sampah di TPST, meliputi dari aspek teknis dan finansial. Perencanaan diawali dengan kegiatan survei dan sampling untuk mendapatkan data berupa kuantitas sampah yang ditangani, data komposisi sampah, densitas sampah, potensi daur ulang sampah, juga kondisi sarana serta prasarana yang ada. Hasil penelitian menunjukkan komposisi sampah terdiri dari sisa makanan dan kebun (44,6%), plastik (30,92%), kardus/karton (9,82%), kain (1,90%), kaca (1,16%), logam (0,60%),karet/kulit 0,44%, B3 rumah tangga (0,2%) dan lain-lain (10,37%). Selain itu terdapat fasilitas lain yang tidak tercatat pada Permen PU nomor 03/PRT/M/2013 yaitu fasilitas berupa kamar tidur, dapur, dan warung. Optimasi pengelolaan sampah dilakukan dengan hanya mengolah jenis sampah kering (plastik, kaca, logam, karet/kulit). Pemilahan dilakukan dengan kecepatan 80 kg/jam/orang agar mencapai nilai reduksi hingga 35,82%, dan memenuhi target pengurangan sampah Jakstrada Kabupaten Sidoarjo tahun 2025. Luas lahan optimasi yang dibutuhkan yaitu 2.931,4 m 2 dengan tenaga kerja berjumlah 50 orang. Lahan yang ada, dapat melayani sampah hingga 6.825 KK dan 36 fasilitas umum. Biaya investasi yang dibutuhkan yaitu Rp 1.157.344.970 dan biaya operasional Rp 2.287.316.928/tahun. Potensi pemasukan dari penjualan dan retribusi yaitu Rp 306.152.422/bulan. Dengan metode NPV proyek redesain ini dianggap layak secara finansial.