The use of microtechnology’s in the construction of water aeration installations

Water aeration systems are highly efficient if the dispersion of air in the water is carried out in a controlled and uniform manner. The use of fine bubble generators ensures this and in addition, creates a small loss of pressure when air passes through them. The paper demonstrates that producing as few air bubbles as possible leads to a more efficient aeration process. Two water aeration installations are compared: - The first has a perforated plate with 152 orifices Ø 0.1 mm; - The second has four perforated plates, each with 113 orifices Ø 0.05 mm; Both installations are successively supplied with the same flow rate of compressed air, at the same temperature and at the same initial dissolved oxygen concentration in the water.

Penyisihan Material Organik dan Nitrogen dengan Proses Aerasi Menggunakan Microbubble Generator (MBG) pada Instalasi Pengolahan Air Limbah (IPAL) Asrama

Sebuah Instalasi Pengolahan Air Limbah (IPAL) di asrama mahasiswi UGM, Yogyakarta memiliki unit reaktor yang terdiri dari ekualisasi, aerasi 1, aerasi 2 dan clarifier dengan proses aerasi secara intermiten menggunakan Microbubble Generator (MBG) dengan fase aerasi dan tanpa aerasi masing-masing selama 15 menit. IPAL tersebut dibangun sebagai upaya dalam memenuhi standar Green Building bagi bangunan lama asrama di UGM untuk mengolah air limbah grey water. Hasil olahan air limbah akan dimanfaatkan di lingkungan asrama. Selama 208 hari beroperasi, kajian mengenai performa IPAL belum pernah dilakukan. Oleh karena itu, diperlukan kajian untuk mengetahui performa dan konsumsi energi pada IPAL dalam menyisihkan parameter pencemar berupa COD, nitrogen dan fosfat. Kajian dilakukan selama 81 hari pengamatan dengan menguji parameter kualitas air limbah pada setiap unit pengolahan. Parameter COD dan amonia telah memenuhi baku mutu Peraturan Menteri Lingkungan Hidup dan Kehutanan No. 68 Tahun 2016 tentang Baku Mutu Air Limbah Domestik, sedangkan parameter fosfat masih belum memenuhi baku mutu Peraturan Daerah D.I.Y. No.7 Tahun 2016 mengenai kegiatan IPAL Komunal. Hasil pengamatan pada performa IPAL, menunjukkan kedua tangki aerasi memiliki performa yang hampir sama, namun keberadaan tangki aerasi 2 tidak memiliki pengaruh yang signifikan dalam menyisihkan parameter pencemar. Pada tangki aerasi 1, efisiensi penyisihan COD mencapai rata-rata sebesar 73,6±17,46%, penyisihan PO4-P sebesar 39,12±14,96%, penyisihan total nitrogen sebesar 56,15±19,6%, efisiensi nitrifikasi sebesar 73,1±20.07% dan efisiensi denitrifikasi sebesar 61,72±27,48%. Total konsumsi energi pada IPAL dengan proses aerasi intermiten, dengan debit rerata 537,84 l/hari sebesar 14,12 kWh/m3 dan biaya sebesar Rp. 20.414/m3. Urutan konsumsi energi terbesar adalah penyisihan fosfat sebesar 5,10 kWh/gPO4-P, kemudian penyisihan amonia sebesar 1,79 kWh/gNH3-N, penyisihan TN sebesar 1,95 kWh/gTN dan penyisihan COD sebesar 0,45 kWh/gCOD. ABSTRACTA Wastewater Treatment Plant (WWTP) in the student dormitory of UGM, Yogyakarta has a reactor unit consists of an equalization, aeration 1, aeration 2, and clarifier with intermittent aeration process using a Microbubble Generator (MBG) with or without aeration for 15 minutes each. The WWTP was built as an effort to meet the Green Building standards for the old dormitory at UGM to make better process of grey water. The processed wastewater will be used for the dormitory environment. Operated for 208 days, there was no former studies for the WWTP. Therefore, a study is needed to determine performance and energy consumption of the WWTP in removing pollutant parameters consisting of COD, nitrogen and phosphate. The study was carried out for 81 days of observation by testing the wastewater quality parameters in each treatment unit. COD and ammonia parameters have met the quality standards of the Regulation of the Minister of Environment and Forestry No. 68 of 2016 concerning Domestic Wastewater Quality Standards, while phosphate doesn’t meet the quality standards of Regional Regulation D.I.Y. No. 7 of 2016 concerning Communal WWTP Activities. Results shows the performance from two aeration tanks are almost the same, but the existence of aeration tank 2 doesn’t have a significant effect. The results in aeration tank 1 showed the COD removal efficiency reached an average of 73.6±17.46%, PO4-P removal 39.12±14.96%, total nitrogen removal 56.15±19.6%, the nitrification efficiency 73.1±20.07% the denitrification efficiency 61.72±27.48%. The total energy consumption with intermittent aeration process with an average discharge of 537.84 l/day is 14.12 kWh/m3 and a cost of Rp. 20,414/m3 with the largest energy use being phosphate removal at 5.10 kWh/gPO4-P, then ammonia removal at 1.79 kWh/gNH3-N, TN removal at 1.95 kWh/gTN and COD removal at 0.45 kWh/gCOD.

Effective Parameters on Fabrication and Modification of Braid Hollow Fiber Membranes: A Review

Hollow fiber membranes (HFMs) possess desired properties such as high surface area, desirable filtration efficiency, high packing density relative to other configurations. Nevertheless, they are often possible to break or damage during the high-pressure cleaning and aeration process. Recently, using the braid reinforcing as support is recommended to improve the mechanical strength of HFMs. The braid hollow fiber membrane (BHFM) is capable apply under higher pressure conditions. This review investigates the fabrication parameters and the methods for the improvement of BHFM performance.

Power Generation and Oxygen Transfer Analyses for Micro Hydro-Turbine Installed in Wastewater Treatment Aeration Tank

This study targets one of the major energy consumers in the U.S. It suggests a new mechanical system that can recover a portion of the energy in Wastewater Treatment Plants (WWTPs). The proposed system entails a hydro-turbine installed above the air diffuser in the aeration tank to extract the water-bubble current's kinetic energy and converts it to electricity. Observing the optimum location of the turbine required multiple experiments where turbine height varies between 35% and 95% (water height percentages above the diffuser), while varying the airflow between 1.42 L/s (3 CFM) and 2.12 L/s (4.5 CFM) with a 0.24 L/s (0.5 CFM) increment. Additionally, three water heights of 38.1 cm (15”), 53.4 cm (21”), and 68.6 cm (27”) were considered to study the influence of the water height. It was noticed that the presence of the system has an adverse effect on the Standard Oxygen Transfer Efficiency (SOTE). Therefore, a small dual-blade propeller was installed right above the diffuser to directly mix the water in the bottom of the tank with the incoming air to enhance the SOTE. The results showed that the maximum reclaimed power was obtained where the hydro-turbine is installed at 65% - 80% above the diffuser. A reduction of up to 7.32% in SOTE was observed when the setup was placed inside the tank compared to the tank alone. The addition of the dual-blade propeller showed an increase in SOTE of 7.27% with a power loss of 6.21%, ensuring the aeration process was at its standards.

Treatment of waste cutting fluid by coagulation-anaerobic hydrolysis (with or without cosubstrate glucose)-aeration process

A coagulation-anaerobic hydrolysis-aeration process was used to treat the waste cutting fluid which was discharged from a metalworking plant, and the operating conditions of each unit were optimized in this paper. The results showed that 9 g/L polyaluminum chloride and 0.3 g/L cationic polyacrylamide were added in the coagulation stage, the TOC was removed by 78.94% and the BOD5/COD of the waste cutting fluid increased from 0.046 to 0.312 before and after coagulation; The coagulation effluent was further treated by anaerobic hydrolysis-aeration, and the TOC removal efficiencies of the biological process and the whole chemical-biological process were 92.77% and 98.48% respectively; Adding glucose as a cosubstrate into the anaerobic hydrolysis can improve the TOC removal efficiency, when the TOC content ratio of coagulation effluent to glucose solution was 7:3, the TOC removal efficiencies of the biological process and the chemical-biological process reached 97.16% and 99.40%, and the total oil removal efficiency of the whole process reached 99.99%; The effluent quality parameters of the coagulation-anaerobic hydrolysis (with cosubstrate glucose)-aeration process met the Class C limits specified in the Wastewater Quality Standards for Discharge to Municipal Sewers (GB/T 31962-2015); that is, the effluent COD, TN, TP and total oil were below 300 mg/L, 25 mg/L, 5 mg/L and 110 mg/L respectively, and the effluent pH was between 6.5–9.5.

Hydraulic Turbine Performance Assessment with Implementation of an Innovative Aeration System

The environmentally friendly concept in terms of water quality represents a condition for developing hydropower plants all around the world. Since 2017, hydropower has represented more than 70% of all renewable energy production and it is essential for the integration of the other renewable sources of energy and for regulation of the grid. To maintain the “green” label concerning the dissolved oxygen level (6 mg DO/L), the energy suppliers should respond to environmental concerns about the operation of hydropower plants. In the context of sustainable development, the ecological degradation of rivers is unacceptable due to the implementation of a hydropower plant on the watercourse. For deep reservoirs or tropical regions, the oxygen level in the water downstream of the hydropower plants may be low and affect the aquatic life for many kilometers downstream. This paper presents a new aeration system for discharged water from hydropower plants that provides water aeration with minimum energy consumption. The influence of the aeration process on the turbine operation and efficiency is analyzed. Experimental measurements are carried out on site on a small Francis turbine. The influence of the aeration process on the turbine mechanical performances (vibration level and relative displacement) and hydraulic performances (turbine efficiency, power output, and pressure fluctuation) is analyzed. The results showed that the impact of the aeration device implementation and operation over the energetic characteristics of the turbine is in the efficiency measurements accuracy range. The aeration through this device did not influence the turbine operation (vibration, level, or pressure fluctuations).

Pembentukan Pupuk Struvite dari Limbah Cair Industri Tempe dengan Proses Aerasi

ABSTRACT Struvite, also known as magnesium ammonium phosphate hexahydrate, is a white crystal with a chemical formula magnesium ammonium phosphate hexahydrate (MgNH4PO4.6H2O). Because of its phosphate content, struvite can be utilized as a fertilizer. Tempeh industrial effluent contains a high concentration of PO4, making it a possible struvite fertilizer producing material. The formation of struvite fertilizer is carried out by the aeration process. This process is able to increase the pH and homogeneity of the solution. The solution of Magnesium Ammonium Phosphate (MAP) is prepared by reacting tempeh industrial wasterwater, Magnesium Chloride (MgCl2), and Ammonium Hydroxide (NH4OH). The MAP ratios used are 1:1:1 and 3:1:1. The temperature was set at 30 °C and pH 9, the airflow rate was carried out at a rate of 0.25 - 1.25 liters per minute. Struvite crystals were analyzed using X-ray Fluorescence (XRF) and Scanning Electron Microscope (SEM). The best struvite fertilizer content is magnesium by 40.3% and phosphorus by 43.9% at an air flow rate of 1.25 liters per minute and a ratio of 3:1:1. Further development can be done by applying struvite fertilizers to plants. Keywords: aeration, crystallization, tempeh industrial wastewater, struvite ABSTRAK Struvite adalah kristal putih yang secara kimiawi dikenal sebagai magnesium amonium fosfat heksahidrat (MgNH4PO4.6H2O). Struvite dapat dimanfaatkan menjadi pupuk karena kandungan fosfat (PO4) di dalamnya. Limbah cair industri tempe memiliki kandungan PO4 yang cukup tinggi, menjadikan limbah cair industri tempe adalah bahan pembentuk pupuk struvite yang potensial. Pembentukan pupuk struvite dilakukan dengan proses aerasi. Proses ini mampu meningkatkan pH dan homogenitas dari larutan. Larutan MAP (Magnesium Amonium Fosfat) dibuat dengan cara mereaksikan limbah cair industri tempe, Magnesium Klorida (MgCl2), dan Amonium Hidroksida (NH4OH). Rasio MAP yang digunakan adalah 1:1:1 dan 3:1:1. Temperatur ditetapkan sebesar 30°C dan pH 9, laju alir udara dilakukan dengan laju 0,25 - 1,25 liter per menit. Kristal struvite dianalisis menggunakan Floresensi sinar-X (XRF) dan Mikroskop Pemindai Elektron (SEM). Kandungan pupuk struvite terbaik adalah magnesium sebesar 40,3% dan fosfor sebesar 43,9% pada konsentrasi 3:1:1 dan laju alir udara 1,25 liter per menit. Pengembangan lebih lanjut dapat dilakukan dengan mengaplikasikan pupuk struvite ke tanaman. Kata Kunci: aerasi, kristalisasi, limbah cair industri tempe, struvite

Pengolahan Limbah Cair Industri Pakan Ternak dengan Kombinasi Proses Aerasi dan Biologi Aerob

ABSTRACT Wastewater is unclean and contains various substances that can risk the lives of humans and animals. This waste usually comes from the results of human actions (including industrialization). Industry must apply the principle of waste control in a careful and integrated system. Aeration is one of the most widely used techniques for improving the physical and chemical characteristics of wastewater. The aerobic microbiological wastewater treatment process utilizes aerobic microbial activity in aerobic conditions to decompose organic matter in wastewater into stable inorganic substances that don’t provide pollution impacts on the environment. This study determines the best time for the aeration process to reduce Chemical Oxygen Demand (COD) or Biological Oxygen Demand (BOD) of animal feed wastewater and the volume ratio of waste, that is, the number of microorganisms to reduce COD and BOD of animal feed wastewater. The study results show that the longer the aeration contact time, the more significant the decrease in COD and BOD values. In addition, the greater the addition of microbial concentration, the more effective the reduction in COD and BOD values. Furthermore, the aeration process time with microbial concentration, which will produce the best COD and BOD reduction, is 6 hours. Unfortunately, the COD and BOD values ??still do not meet the wastewater quality standards in the aeration process. Still, with microbial concentrations, COD and BOD values ??reduction targets will be obtained in the aerobic biological process, following the wastewater quality standards. Finally, wastewater processing from the animal feed industry with a combination of aeration and aerobic biology can meet quality standards. Keywords: aerobic, anaerobic, animal feed, BOD, COD, wastewater ABSTRAK Air limbah merupakan air yang tidak bersih atau yang mempunyai kandungan berbagai zat yang berbahaya bagi kelangsungan hidup manusia, hewan, dan tumbuhan. Biasanya limbah dihasilkan dari kegiatan manusia (termasuk industrialisasi) sehingga sudah sepatutnya perindustrian mengelola hasil buangannya sesuai kaidah pengolahan limbah secara terpadu, efisien, dan efektif. Aerasi merupakan salah satu teknik yang paling banyak digunakan dalam perbaikan karakteristik fisik dan kimiawi air limbah. Terdapat berbagai proses pengolahan limbah di mana salah satunya dengan memanfaatkan aktivitas mikroba aerob untuk menguraikan zat organik dalam kondisi aerob menjadi zat anorganik yang stabil yang tidak mencemari lingkungan. Tujuan dari penelitian ini adalah mengetahui waktu terbaik proses aerasi terhadap penurunan Chemical Oxygen Demand (COD) atau Biological Oxygen Demand (BOD) limbah cair pakan ternak dan mengetahui rasio volume limbah, yaitu jumlah mikroorganisme terhadap penurunan COD dan BOD limbah cair pakan ternak. Kesimpulan hasil kajian yaitu waktu pengontakan aerasi semakin lama dan penambahan konsentrasi mikroba berpengaruh pada penurunan nilai COD dan BOD dengan penurunan terbaik didapatkan pada waktu 6 jam. Nilai COD dan BOD proses biologi aerob dengan penambahan konsentrasi mikroba pada proses aerasi dan kombinasi aerasi dan biologi aerob telah memenuhi standar baku mutu limbah tetapi pada proses aerasi belum. Kata kunci: aerob, anaerob, BOD, COD, limbah cair, pakan ternak

Advanced treatment of effluent extended aeration process using biological aerated filter (BAF) with natural media: modification in media, design and backwashing process

Biological aerated filters (BAFs) have high filtration efficiency due to their tolerance of hydraulic and organic shocks are suitable for the treatment of complex and sanitary wastewater. In this study, for the first time, natural media of date kernel from Bam city was used as the BAF reactor media, with a meshing sand filter separated by a standard metal grid from the natural filter section used at the end of the reactor. This can be considered an innovation in the media and filtration. Aeration in the related reactor with 160 cm height was performed bilaterally as up-flow and continuously by nozzles throughout the reactor media. In this work, the actual effluent of the hospital wastewater treatment plant was employed as the inflow wastewater to the reactor, and its organic and inorganic parameters were measured before and after the treatment by the BAF reactor. The backwashing process was also studied in three ways: bottom backwashing (TB), top backwashing (BB), and top and bottom backwashing (TBBS), to determine the amount of water consumed and to achieve the desired result. According to the results obtained in this study, the removal efficiencies of inorganic and microbial contaminants, amoxicillin and azithromycin were obtained as follows: BOD5: 98.48%, COD: 92.42%, $${\text{NO}}_{3}^{ - }$$ NO 3 - : 99.4%, P: 93.3%, Coliforms: 97%, Color: 42.8%, Turbidity: 95%, Sulphate: 30%, TSS: 98.9%, Amoxicillin: 20% and azithromycin: 13%. In the backwashing process, the amount of water consumed in these three TB, BB, and TBBS methods were obtained 300, 164, and 118 L, respectively, So, TBBS method was selected as the optimal method. Based on the results obtained in this study, it is concluded that the BAF process with natural date kernel has a high efficiency in removing organic and inorganic contaminants from hospital wastewater, also the concentration of most of the effluent parameters was less or in accordance with EPA standard.