Auswahl der wissenschaftlichen Literatur zum Thema „Separace amoniaku“

Ammonia in waste water is a major pollutant produced in industrial and agricultural waste water. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ammonium ion onto zeolites. In many cases, conventional methods are very costly and inefficient, and therefore, there is a need for an alternative separation technique for more efficient removal of ammonia from waste waters. The aim of this study is to investigate the performance of the combination of ozonation and absorption through membrane processes to remove ammonia from wastewater using natural hot spring water (NHSW) as absorbent. Experimental results show that operating variables such as time and pH of absorbent solution are found to remarkably influence the removal process efficiency. Based on experimental results ozonation can improve ammonia removal efficiency through the hollow fiber membrane contactor. Ammonia removal efficiencies and overall mass transfer coefficients increase with decreasing pH of absorbent solution. Keywords: ammonia, mass transfer, membrane, ozonation, removal efficiencyAbstrak Amonia di dalam air limbah merupakan polutan utama yang berasal dari air limbah industri dan pertanian. Amonia kebanyak disisihkan dengan teknologi konvensional seperti aerasi di menara isian, pengolahan secara biologi atau penyerapan sebagai ion amonium pada zeolit. Dalam banyak hal, metode konvensional sangat mahal dan kurang efisien, sehingga diperlukan teknik separasi alternatif untuk proses penyisihan amonia dari air limbah yang lebih efisien. Tujuan dari studi ini adalah untuk menyelidiki kinerja kombinasi proses ozonasi dan proses absorbsi melalui membran untuk menyisihkan amonia dari air limbah menggunakan absorben berbahan dasar air dari sumber air panas. Hasil eksperimen memperlihatkan bahwa variabel operasi, seperti waktu dan pH larutan penyerap, sangat mempengaruhi efisiensi proses penyisihan amonia. Berdasarkan hasil eksperimen, ozonasi dapat meningkatkan efisiensi penyisihan ammonia melalui kontaktor membran serat berlubang. Efisiensi penyisihan amonia dan koefisien perpindahan massa keseluruhan naik dengan turunnya pH larutan penyerap.Kata kunci: amonia, perpindahan massa, membran, ozonasi, efisiensi penyisihan

The presence of H2S in natural gas is very detrimental to ammonia industry because it can poison and deactivate steam reforming catalysts. In the ammonia plant Pusri-IB PT. Pusri Palembang, H2S was separated in the Desulfurizer Unit (201-D) by adsorption using ZnO adsorbent at low temperature (28 ° C). Unfortunately, in this process the ZnO adsorbent cannot be regenerated so that within one year the ZnO adsorbent will be saturated with sulfur. The alternative process of H2S separation is to dissociate H2S into its constituent elements (hydrogen and sulfur) with catalytic process. The magnesium oxide catalyst was chosen because magnesium oxide is a metal oxide compound widely known in the catalysis process and has two active sites. The highest H2S conversion that can be achieved by MgO catalyst is 92.29%. Unlike ZnO, MgO does not absorb H2S, but catalyzes the dissociation of H2S into hydrogen and solid sulfur without being changed consumed by the reaction itself so that the MgO catalyst has a longer life time than the ZnO adsorbent.A B S T R A KKandungan H2S dalam gas alam sangat merugikan bagi industri amoniak karena dapat meracuni dan mendeaktivasi katalis steam reforming. Di pabrik amoniak Pusri-IB PT. Pusri Palembang, H2S dipisahkan di Unit Desulfurizer (201-D) secara adsorpsi dengan menggunakan adsorben ZnO pada temperatur rendah (28 ° C). Namun sangat disayangkan, pada proses ini adsorben ZnO tidak dapat diregenerasi sehingga dalam kurun waktu satu tahun adsorben ZnO akan jenuh oleh sulfur. Salah satu alternatif proses pemisahan H2S adalah dengan mendisosiasi H2S menjadi unsur penyusunnya yaitu hidrogen dan sulfur dengan bantuan katalis. Katalis magnesium oksida dipilih karena magnesium oksida merupakan senyawa metal oksida yang penggunaannya sudah dikenal luas dalam proses katalisis serta memiliki dua gugus aktif. Konversi H2S tertinggi yang dapat dicapai katalis MgO adalah sebesar 92,29%. Berbeda halnya dengan ZnO, MgO tidak menyerap H2S, namun mengkatalisis proses disosiasi H2S menjadi hidrogen dan sulfur padat tanpa mengalami perubahan atau terkonsumsi oleh reaksi itu sendiri sehingga katalis MgO memiliki life time yang lebih lama dibanding adsorben ZnO.

Study of reforming unit modification of ammonia plant Pusri iii and gas producer utilization as subtitution fuel for natural gas in PT Pupuk Sriwidjaja. This study dealt with an energy conservation program at the reforming unit in PT Pupuk Sriwidjaja, to anticipate the increase of price and possible shortage of natural gas in the nearfillure. A potential reduction of natural gas consumption was evaluated based on thermodynamic modeling and simulation. Three process modifications were studied and their performance had heen compared to the existing unit: KRES (KBR Reforming Exchanger System); totally replace the existing primary reformer; ATR (AutoThermal Reformer): totally replace the existing primary reformer; KRES-revamp: appending KRES on the existing unit. Compared to that of the existing reformer of 37.15 MMBtu/metric ton of NH3 the natural gas consumption in the proposed modified process are lower by 9%, 15%, and 20% in KRES-revamp, KRES. and ATR, respectively. Unfortunately, the proposed modified process produces less steam as by-product due to the decrease of waste sensible heat. Therefore, to restore the steam supply, the proposed modified process requires an additional auxiliary boiler with a capacity of 105 tons/hour for KRES-revamp, 137 tons/hour for KRES and 97 tons/hour for ATR. KRES-revamp has been considered as the most attractive modification. This modification may give an annual natural gas saving of about 8.39%. In addition based on investment aspect. KRES-revamp is very attractive due to payback period of about 10 months. The use of producer gas (produced from the gasification of coal) as a substitute of natural gas for fuel was found to be thermodynamically feasible. But a separate study shows that the producer gas price is about 5 USD/MMBtu. Thus, the use of producer gas was not attractive yet economically. Moreover, the producer gas consumption combined with natural gas is higher than natural gas only (37,26 vs. 34,86 MMBtu/metric ton of NH3 with some modifications in combustion system.Keywords: reforming unit, producer gas and energy efficiency. AbstrakSehuhungan dengan kecenderungan kenaikan harga dan ketidakpastian pasokan gas alam, PT Pupuk Sriwidjaja telah menyusun rencana penghematan konsumsi gas alam dengan modifikasi proses maupun pemanfaatan batubara sebagai bahan bakar alternatif. Penelitian dilakukan terhadap empat konfigurasi existing unit yang terdiri dari primary and secondary reformers, KRES yang berupa unit baru pengganti existing unit, ATR yang berupa unit baru pengganti existing unit, KRES-revamp yang menggahung KRES dengan existing unit. Secara termodinamika, teknologi produksi gas sintesis KRES-revamp, KRES. ATR terbukti lebih efisien dan dapat mengurangi konsumsi gas alam untuk pabrik amoniak berturut-turut: 9%, 15%. dan 20% dari kebutuhan gas alam untuk reformer konvensional sebesar 37,15 MMBtu/MT NH3. Walaupun efisiensi energi lebih baik, teknologi-teknologi tersebut juga memerlukan modifikasi steam system dan mengakibatkan penambahan auxiliary boiler dengan kapasitas berturut-turut: 105, 137, dan 97 ton/jam. Selanjutnya kajian diperdalam untuk KRES-revamp. Penerapan KRES-revamp dengan kapasitas produksi amoniak tetap 1200 MTPD (kasus yang pertama) dapat menurunkan biaya produksi hingga 8,39%/tahun. Hanya dengan memperhatikan investasi untuk tambahan KRES dan tambahan auxilliary boiler, Payback Period diperkirakan 10 bulan. Substitusi gas alam dengan gas produser untuk saat ini kurang menarik karena menurut kajian lain harga gas hasil gasifikasi diperkirakan mencapai 5 USD/MMBtu (pada kondisi tertentu). Terlebih lagi pemanfaatan gas produser sebagai bahan bakar pengganti gas alam memerlukan beberapa modifikasi pada sistem pembakaran. Di samping itu, konsumsi total energi gabungan gas alam dan gas produser lebih tinggi daripada yang hanya gas alam (37,26 vs. 34,86 MMBtu/MT NH3.Kata kunci: Reforming unit, Gas produser, Efisiensi Energi.

ABSTRAKPengolahan monasit Bangka secara basa dilakukan melalui tahapan dekomposisi; pelarutan parsial pH 3,7; pengendapan parsial pH 6,3; dan pengendapan total pH 9,8. Proses tersebut menghasilkan natrium fosfat, Rare Earth (RE) hidroksida, uranium (U), dan torium (Th). Pada proses dekomposisi, 99 % natrium fosfat telah terambil dan RE hidroksida telah terpisah dari U dan Th dengan recovery 85 %. Sementara itu, U dan Th yang dihasilkan masih bercampur sehingga perlu dipisahkan. Pemurnian Th dari U pada monasit telah dilakukan dengan metode Solvent Impregnated Resin (SIR) dan dilanjutkan dengan proses elusi setelah SIR. Hasilnya, Th masih berada pada fase cairan berupa larutan torium nitrat [Th(NO3)2] sehingga perlu diendapkan sebagai torium hidroksida [Th(OH)2] untuk memudahkan proses berikutnya. Pengendapan Th setelah proses SIR dilakukan dengan tujuan memperoleh kondisi optimum pengendapan. Resin penyokong yang digunakan adalah amberlite XAD-16 menggunakan ekstraktan yang diimpregnasikan dengan tributyl phosphate (TBP), reagen elusi asam nitrat (HNO3) encer dan reagen pengendapan amoniak (NH4OH). Parameter yang diteliti adalah pengaruh pH dan waktu pengendapan terhadap recovery Th. Hasil penelitian menunjukkan kondisi optimum pengendapan Th dari monasit setelah proses SIR pada pH 1,2 dan waktu 60 menit dengan recovery 84,74 % Th; 3,26 % U; 34,74 % RE; dan 8,52 % PO4.ABSTRACTAlkaline processing of Bangka monazite is carried out through stages like decomposition; partial dissolution pH 3.7; partial precipitation pH 6.3; and total precipitation pH 9.8. These procesess produce sodium phosphate, Rare Earth (RE) Hydroxide, uranium (U), and thorium (Th). On decomposition procsess, 99 % of sodium phosphate had been recovered and RE Hydroxide was separated from U and Th with 85% recovery. Meanwhile, the U and Th products were still mixed so that needs to separate. Purification of Th from U in monazite had been carried out by using Solvent Impregnated Resin (SIR) method and continued by elution after SIR. The result is that Th is still in the liquid phase as thorium nitrate [Th(NO3)2] solution so it needs to be precipitated as thorium hydroxide [Th(OH)2] to facilitate the next process. Precipitation of Th after SIR process is conducted with the aim to obtain optimum precipitation condition. The supporting resin used is amberlite XAD-16 with impregnated tributyl phosphate (TBP) extractant, dilute nitric acid (HNO3) as elution reagent, and ammonium hydroxide (NH4OH) as precipitation reagent. The observed parameters are the effect of pH and precipitation time on Th recovery. The results show that the optimum precipitation conditions of Th from monazite after SIR process is on pH 1.2 and 60 minutes time, resulting recovery of 84.74 % Th, 3.26 % U, 34,74 % RE, and 8.52 % PO4.

<p>Minyak bumi adalah salah satu bahan bakar fosil dan bahan kimia yang termasuk dalam bahan berbahaya dan beracun, sehingga memerlukan penanganan khusus dalam penanganan perminyakan di lapangan "X". Gathering Station Center adalah salah satu stasiun pengumpul yang mengumpulkan dan merawat minyak dari sumur, dimana menghasilkan air limbah kemudian diproses di Instalasi Pengolahan Air (IPAL) sebelum dibuang ke lingkungan. Tujuan penelitian ini adalah memahami instalasi pengolahan air limbah dan meneliti konsentrasi polutan inlet dan outlet di IPAL. Metode yang digunakan adalah analisis survei dan analisis, parameter yang digunakan secara keseluruhan adalah Suhu, pH, BOD, COD, Minyak, Sulfida (sebagai H2S), dan amonia (sebagai NH3-N). Semuanya didasarkan pada PerMenLH No. 4 Tahun 2007 tentang ambang air limbah untuk industri minyak, gas, dan panas bumi. Minyak yang mengalir dilapangan "X" dengan menggunakan flowline kemudian diakhiri dengan choke manifold kemudian dialirkan ke pemisah untuk memisahkan berdasarkan pengendapan gravitasi. Scrubber digunakan untuk memastikan bahwa minyak dan gas telah betul-betul terpisah dari air. Air ini kemudian diinjeksikan kedalam sumur untuk <em>pressure maintenaince</em>, atau jika memenuhi syarat dialirkan ke sungai. Dari semua parameter, air limbah tersebut aman untuk lingkungan karena masih memenuhi syarat dalam PerMenLH No. 4 Tahun 2007.</p><p><em>Petroleum is one of the fossil fuels and chemicals included in hazardous and toxic materials, so it requires special handling in handling oil in the "X" field. Gathering Station Center is one of the collection stations that collect and treat oil from wells, which produce waste water and then it is processed at the Water Treatment Plant (WWTP) before being discharged into the environment. The purpose of this study is to understand the wastewater treatment plant and examine the concentration of inlet and outlet pollutants at WWTP. The method used is survey analysis and analysis, the parameters used as a whole are Temperature, pH, BOD, COD, Oil, Sulfide (as H2S), and ammonia (as NH3-N). Everything is based on PerMenLH No. 4 of 2007 concerning threshold wastewater for the oil, gas and geothermal industry. </em><em>Oil flowing in the "X" field using a flowline is then terminated with a choke manifold and then flowed to the separator to separate based on gravity deposition. Scrubbers are used to ensure that oil and gas are completely separated from water. This water is then injected into the well for pressure maintenance, or if it meets the requirements, it is flowed into the river. Of all the parameters, the waste water is safe for the environment because it still meets the requirements in PerMenLH No. 4 of 2007.</em></p>

<p>Urease merupakam enzim yang digunakan dalam hidrolisis urea menjadi amoniak dan asam bikarbonat dan telah banyak digunakan dalam proses industri. Tujuan penelitian adalah isolasi dan pemurnian urease dari kacang panjang serta karakterisasinya. Penelitian dimulai dengan melakukan perkecambahan biji kacang panjang selama 8 hari. Kecambah biji kacang panjang selanjutnya diekstraksi dengan menggunakan buffer fosfat pH 7 dan dipisahkan menggunakan sentrifugasi sehingga diperoleh ekstrak kasar urease. Ekstrak kasar urease selanjutnya difraksinasi menggunakan aseton pada tingkat konsentrasi 20, 40, 60 dan 80%. Fraksi yang mempunyai aktivitas spesifik paling tinggi selanjutnya dianalisis menggunakan metode SDS-PAGE untuk menentukan berat molekulnya dan dikarakterisasi lanjut meliputi: pengaruh suhu, pH, konsentrasi substrat dan penambahan ion logam terhadap aktivitas urease. Aktivitas urease ditentukan dengan metode Nessler. Hasil penelitian menunjukkan aktivitas spesifik urease dari kacang panjang paling tinggi ditemukan pada fraksi aseton (FA) 20. Hasil analisis berat molekul dengan metode SDS-PAGE diperoleh beberapa pita protein yang diduga berukuran sekitar 25 KDa dan 17 KDa. Kondisi optimum dari aktivitas urease diperoleh pada suhu 30 ºC, pH 7 dan konsentrasi urea 16,6 mM dengan nilai aktivitas 407,62 U/mL. EDTA dan ion logam dalam CaCl₂, NaCl, NiCl₂ dan CuCl₂pada variasi konsentrasi 10^-3, 10^-4 dan 10^-5M merupakan inhibitor urease FA 20 dari kacang panjang.</p><p><strong><span lang="EN-US">Partial Purification and Characterization of Urease from Asparagus Bean (<em>Vigna unguiculata subsp sesquipedalis </em>L<em>.</em>). </span></strong><span lang="EN-US">Urease is an enzyme used in urea hydrolysis to ammonia and bicarbonate acid and has been widely used in industrial processes. The study focused on isolation and purification of urease from asparagus beans and its characterization. The study was started with germination of asparagus beans for 8 days. Germinated asparagus beans were further extracted using phosphate buffer pH 7 and separated by centrifugation to obtain a crude extract of urease. The crude extract of urease was further fractionated using acetone at concentrations of 20, 40, 60 and 80%. The fraction with highest specific activity was then </span><span>analyzed using SDS-PAGE method to determine its molecule weight and characterized further including the influence of </span><span lang="EN-US">temperature, pH, substrate concentration, and metal ion addition to urease activity. The urease activity was determined by the Nessler̕ s method. The results showed that the specific activity of urease from asparagus beans was found with highest activity in fraction of acetone (FA) 20. Analytical result using SDS-PAGE method was obtained some protein bands having molecular weights about 25 KD and 17 KDa. The optimum conditions of urease activity was obtained at 30 °C, pH 7, incubation time 20 min and urea concentration 16.6 mM with activity value 407.62 U/mL. EDTA and </span><span>metal ions contained in </span><span lang="EN-US">CaCl₂, NaCl, NiCl₂ and CuCl₂ at concentrations of 10^-3, 10^-4 and 10^-5 M were FA 20 urease inhibitors.</span></p>

This diploma thesis deals with the solution of ammonia separation from waste raw materials of agricultural production. It focuses on determining the efficiency of desorption from an experimental stripping device depending on the measurement temperature. Ammonia water solutions and liquid digestate samples from technical practice were used to verify the functionality of the equipment. Increasing separation efficiency with increasing temperature has been demonstrated. The device was gradually improved during the measurement for a better profitability of the separation process. The results of the experiments are discussed concerning the theoretical assumptions and compared with other methods of ammonia separation.