Hasil Pencarian  ::  Simpan CSV :: Kembali

"Untuk memenuhi kebutuhan pupuk dan produk fosfor lainnya, eksploitasi fosfor tambang dilakukan secara besar-besaran. Lumpur aktif dari Instalasi Pengolahan Air Limbah (IPAL) mempunyai potensi besar untuk dijadikan sumber fosfor baru. Oleh karena itu, penelitian ini bertujuan untuk menganalisis kondisi optimum dan pengaruh karakteristik lumpur aktif terhadap pelepasan fosfor dari senyawa kalsium fosfat, yaitu hidroksiapatit (HAP). Penelitian ini juga mencari laju reaksi sebagai dasar penentuan dimensi reaktor. Sebelum melakukan eksperimen, dilakukan simulasi menggunakan Visual MINTEQ 3.1 untuk menentukan kondisi ideal pelepasan fosfor. Eksperimen dilakukan menggunakan reaktor batch dengan variasi nilai pH dan waktu kontak. Hasil eksperimen menunjukkan bahwa semakin rendah nilai pH, maka pelepasan fosfor semakin tinggi sehingga nilai pH 4 dinilai menjadi nilai pH yang paling efektif. Sedangkan berdasarkan waktu kontak, dengan rentang waktu 120 menit, telah terjadi proses pelarutan dan presipitasi secara dinamis sampai mencapai titik kesetimbangan, yaitu menit ke-30. Karakteristik dari lumpur aktif juga dapat mempengaruhi pelepasan fosfor. Kalsium, sebagai kandungan logam tertinggi di lumpur aktif berdasarkan pengujian, berperan penting karena kemudahannya untuk terikat dengan fosfat dan membentuk senyawa baru sehingga menurunkan konsentrasi fosfor pada larutan. Sedangkan, nilai TSS/VSS pada lumpur aktif dianggap tidak mempengaruhi secara signifikan. Intervensi pada proses presipitasi maupun pelepasan fosfor terjadi pada nilai TSS/VSS yang sangat tinggi. Adapun laju reaksi dihitung menggunakan kesetimbangan massa dan didapatkan koefisien laju reaksi tertinggi pada pH 4, yaitu 0,00339/menit.

---

Mining phosphorus exploitation is carried out on a large scale to meet the demand for fertilizers and other phosphorus products. Activated sludge from the Wastewater Treatment Plant (WWTP) has great potential to be used as a new source of phosphorus. Therefore, this study aims to analyze the optimum conditions and the effect of activated sludge characteristics on the release of phosphorus from calcium phosphate compounds, namely hydroxyapatite (HAP). This research is also looking for the rate of reaction as a basis for determining the dimensions of the reactor. Before experimenting, a simulation was carried out using Visual MINTEQ 3.1 to determine the ideal conditions for the release of phosphorus. Experiments were carried out using a batch reactor with pH values and contact time variations. The experimental results show that the lower the pH value, the higher the release of phosphorus, so a pH value of 4 is considered the most effective. Meanwhile, based on the contact time, with a period of 120 minutes, a dynamic dissolution and precipitation process has occurred until it reaches an equilibrium point, which is 30 minute. The characteristics of the activated sludge can also affect the release of phosphorus. Calcium, as the highest metal content in activated sludge based on testing, plays an important role because of its ease in bonding with phosphates and forming new compounds thereby reducing the concentration of phosphorus in solution. Meanwhile, the value of TSS/VSS in activated sludge is considered not to have a significant effect. Intervention in the process of precipitation and release of phosphorus occurs at very high TSS/VSS values. The reaction rate was calculated using a mass balance and the highest reaction rate coefficient was obtained at pH 4, which was 0.00339/minute."

"Melalui penelitian ini, signifikansi dari efek kavitasi hidrodinamika dan ultrasonik dan juga pemangsa radikal akan diketahui dan dievaluasi melalui konstanta laju reaksi dan bilangan Hatta. Dalam penelitian ini, pembelajaran literatur akan dilakukan pertama, agar dapat melanjutkan penentuan model dan input pada penelitian ini. Kemudian, pembentukan program akan dilaksanakan dan program tersebut akan divalidasi melalui data yang telah diperoleh dari eksperimen sebelumnya. Hasil dari program kemudian akan dianalisa dan dibahas. Untuk pembentukan program, perangkat lunak matematis, MATLAB, akan dipakai. Hasil dari penelitian ini menunjukkan bahwa dalam segi konsumsi ozon, konfigurasi ozonasi tunggal mengkonsumsi ozon paling tinggi, sedangkan konfigurasi ozonasi dan kavitasi ultrasonik adalah yang paling rendah. Hal ini dapat dikaitkan dalam pembentukan radikal bahwa kavitasi ultrasonik adalah yang tertinggi. Dari riset ini, harga kO3 untuk ozonasi tunggal adalah yang tertinggi, mencapai 5.55 x 106, sedangkan konfigurasi ozonasi - kavitasi ultrasonik adalah yang terendah, mencapai 4.17 x 105. Dari segi harga bilangan Hatta, ozonasi tunggal adalah yang tertinggi dengan harga 3.80 x 107, sedangkan konfigurasi ozonasi - hidrodinamika - ultrasonik adalah yang terendah, mencapai 4.28 x 105.

---

Through this study, the significance of effects of hydrodynamic and ultrasonic cavitation along with radical scavengers are determined and evaluated based on the reaction rate constant and Hatta number. In this research, studies on literature is carried out, along with the model and input determination as the next step. Next, the program is developed and is validated based on data obtained from experiments. Results from the program is then analysed for discussions and conclusions. For the program?s development, the mathematical software, MATLAB, is used. Results from this research has shown that in terms of ozone consumption, single ozonation method is the highest, whereas a combination of ozonation and ultrasonic cavitation is the lowest. This can be related in terms of radical formation due to cavitation that ultrasonic is the highest. From the conducted research, kO3 value for ozonation is the highest, reaching a max kO3 of 5.55 x 106, while the lowest is ozonation-ultrasonic cavitation, reaching a max kO3 of 4.17 x 105. And in terms of Hatta number, ozonation is the highest with Ha number reaching 3.80 x 107, while ozonationhydrodynamic cavitation-ultrasonic cavitation is the lowest, reaching 4.28 x 105."

"Learning the basics of physical chemistry with a unique, innovative approach. Georg Job and Regina Rueffler introduce readers to an almost intuitive understanding of the two fundamental concepts, chemical potential and entropy. Avoiding complex mathematics, these concepts are illustrated with the help of numerous demonstration experiments. Using these concepts, the subjects of chemical equilibria, kinetics and electrochemistry are presented at an undergraduate level. The basic quantities and equations necessary for the qualitative and quantitative description of chemical transformations are introduced by using everyday experiences and particularly more than one hundred illustrative experiments, many presented online as videos. These are in turn supplemented by nearly 400 figures, and by learning objectives for each chapter. From a review of the German edition: This book is the most revolutionary textbook on physical chemistry that has been published in the last few decades."