Avaliação das variáveis físico-químicas de um reservatório subtropical no noroeste da Argentina

AIM: The Escaba dam is located in the south of the Tucumán province, Argentina, at 650 m above sea level. It has an extension of 541 ha. and a depth of 65 m and its tributaries are the Chavarría, Las Moras, El Chorro and Singuil rivers. The climate is mild with dry winters and rainy summers. The objective of this study was to characterize physicochemical parameters in the limnetic zone of the dam and the mouths of the tributaries to determine the water quality. METHODS: Seasonal sampling was carried out between August 2010 and May 2012. Temperature, transparency, pH and electrical conductivity were field measured, whereas dissolved oxygen, biochemical oxygen demand (BOD5), major ion constituents and nitrogen and phosphate compounds were analyzed at the laboratory. RESULTS: The water was classified as sodium-calcium-bicarbonate with neutral to alkaline pH, and thermal stratification during spring and summer. The water assayed was well oxygenated except for the bottom of the limnetic zone during the summer months. Lowest transparency was measured in the El Chorro River in November 2011 (0.12 m) and highest degree of transparency in the Singuil River during the winter of 2010 (4.1 m). The waters assayed showed weak mineralization with conductivities between 83 and 218 µS.cm-1. Maximum BOD5 value (183 mg.L-1) was measured in the Singuil River in spring 2010. Highest values for the different nitrogen compounds were as follows: 7 mg NO3-.L-1 at the bottom of the limnetic zone in August 2010, 0.07 mg NO2-.L-1 in the Las Moras River in May 2011 and 1.8 mg NH4+.L-1 in the Chavarría River in March 2011. During the summer of 2012 orthophosphate reached a value of 0.22 mg.L-1 at the bottom of the limnetic zone. The TN/TP ratio revealed that phosphate was generally the limiting factor and rarely nitrogen. CONCLUSIONS: Considering the TN, TP and transparency parameters the ecosystem was classified as hypertrophic. PCA allowed a seasonal differentiation of the sites, and components 1 and 2 classified the samples according to nutrient gradient, dissolved oxygen, BOD5 and temperature.OBJETIVO: A represa Escaba está localizada ao sul da província de Tucumán, a 650 metros de altitude, sua extensão é de 541 ha, tem 65 m de profundidade e seus afluentes são os Rios Chavarria, Las Moras, El Chorro e Singuil. O clima é temperado, com invernos secos e verões chuvosos. O objetivo do estudo foi caracterizar as propriedades físicas e químicas das águas limnéticas da represa e da foz dos seus afluentes, para interpretar a qualidade de suas águas. MÉTODOS: Realizaram-se amostragens estacionais de agosto de 2010 até maio de 2012. As variáveis medidas in situ foram: temperatura, transparência, pH, condutividade elétrica, e no laboratório foram analisados: oxigênio dissolvido, demanda bioquímica de oxigênio (DBO5), íons principais, compostos nitrogenados e fosfatados. RESULTADOS: O tipo de água é bicarbonatada-cálcica-sódica, de neutra a alcalina e detectou-se estratificação térmica na primavera e verão. Com exceção da zona limnética: fundo, nos meses mais quentes, as águas estiveram bem oxigenadas. Em novembro de 2011 no rio El Chorro, obteve-se o valor mais baixo de transparência: 0,12 m e o valor mais elevado foi de 4,1 m no rio Singuil no inverno de 2010. Observou-se uma mineralização fraca com condutividades que variaram entre 83 e 218 µS.cm-1. A DBO5 atingiu o registro máximo de 183 mg L-1 na primavera de 2010 no rio Singuil. Os valores mais altos dos compostos nitrogenados detectados foram: 7 mg NO3-.L-1 (zona limnética: fundo, agosto/2010), 0,07 mg NO2-.L-1 (rio Las Moras, maio/2011) e 1,8 mg NH4+.L-1 (rio Chavarría, março/2011). No verão de 2012, o ortofosfato atingiu 0,22 mg.L-1 no fundo da zona limnética. A proporção NT/PT mostrou o fósforo como limitante, e o nitrogênio em raras ocasiões. CONCLUSÕES: O ecossistema analisado foi classificado como hipertrófico considerando NT, PT e transparência. O ACP permitiu uma diferenciação estacional dos sítios, os eixos 1 e 2 separaram as amostras de acordo aos gradientes dos nutrientes, oxigênio dissolvido, DBO5 e temperatura.Fil: Tracanna, Beatriz Concepcion. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Limnología del Noroeste Argentino; Argentina. Fundacion Miguel Lillo. Direccion de Botanica. Instituto de Ficologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Martínez de Marco, Silvia Nelly. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Limnología del Noroeste Argentino; Argentina. Fundacion Miguel Lillo. Direccion de Botanica. Instituto de Ficologia; ArgentinaFil: Taboada, María de Los Ángeles. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Limnología del Noroeste Argentino; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Mirande, Virginia. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Limnología del Noroeste Argentino; Argentina. Fundacion Miguel Lillo. Direccion de Botanica. Instituto de Ficologia; ArgentinaFil: Gultemirian, Maria de Lourdes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Isasmendi, Sara Celina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Limnología del Noroeste Argentino; Argentin

Investigation of the Corrosion and Scaling Potentials of Raw and Treated Water and Its Effect on Concrete Tanks at Al-Tayyaraa Water Treatment Plant

تم إجراء هذه الدراسة لتقييم الامكانيات التآكلية وتكوين التكلس للمياه الخام والمعالجة  في محطة الطيارة لمعالجة المياه خلال فترة اثني عشر شهرا بدءا من يناير حتى ديسمبر 2016. تم النظر في ثلاثة مؤشرات للتآكل والقياس في هذه الدراسة بما في ذلك مؤشر ريزنار (Ryznar Index (RI))  ومؤشر لانجيلير للتشبع (Langelier Saturation Index (LSI)) والمؤشر العدواني (Aggressive Index (AI)). في هذا البحث تم قياس معاملات جودة المياه pH، Alk (Ca) ، درجة الحرارة، الكالسيوم متمثلا ﺒ (CaCO3)، و أخيرا المعامل TDS. واظهرت النتائج للمياه الخام ان قيم LSI  و RI  كانت على التوالي (0.14-0.504) و (0.03-0.4)  في حين كانت نتائج نفس المؤشرين للمياه المعالجة  هي (6.956 -7.62) و (7.02-7.7) على التوالي. وكانت نتائج المؤشر AI للمياه الخام والمياه المعالجة هي (11.77-12) و (11.67-11.948 ) على التوالي. وكشفت القيم المحسوبة  للمؤشر LSI أن المياه المعالجة والماء الخام كانت متوازنة أو ممكن تكون طبقة رقيقة جدا من الترسبات. أشارت قيم المؤشر RI إلى أن المياه الخام والمعالجة كانت مسببة للتآكل وأظهرت قيم المؤشر العدواني (AI) أن الماء كان  مسببا لتآكل معتدل وليس له تأثير واضح على الخزان الخرساني في محطات معالجة المياه.This study is conducted to evaluate corrosion and scaling potentials of raw and treated water at Al-Tayyaraa water treatment plant during a period of twelve months, starting from January to December 2016. Three indices of corrosion and scaling in this study are considered including Ryznar Index (RI), Langelier Saturation Index (LSI), and Aggressive Index (AI). Water quality parameters pH, Alk, (Ca), temperature, calcium as CaCO3, and (TDS) are measured. For raw water, the values of LSI and RI are (0.14-0.504) and (6.956 -7.62), respectively, whereas for treated water, the values of LSI and RI are (0.03-0.4) and (7.02-7.7), respectively. The values of AI are (11.77-12) for raw water and (11.67-11.948) for treated water. The calculated values of Langelier Saturation Index (LSI) reveal that the treated and raw water are balanced to some faint coating (light scale forming). The values of RI point that the raw and treated water are corrosive and values of aggressive index show that the water is moderate corrosion and no obvious effect on concrete tank at water treatment plants

PENCEGAHAN TERBENTUK NYA PRODUK SCALE PADA PIPA PRODUKSI AREA MINAS DENGAN INJEKSI CHEMICAL SCALE INHIBITOR

Scale is a collection of deposits that become crusted and can cover holes, production tubes and valves so as to block the flow of fluid. Scale can reduce the diameter of the production pipe and cause the fluid flow to decrease so that the amount of production is reduced. In addition, the existence of a scale can cause an increase in pressure in the pipe, if the scale is too large it can cause the production pipe to burst. For that we need treatment for the scale case that occurs, how to overcome and reduce the possibility of scale formation on the inside of the pipe. In the production facility, problems that can interfere with the distribution of crude oil (crude oil) are often encountered. This is generally caused by the formation of deposits (scale) along the distribution pipe. Scale is a solid (crust) resulting from crystallization and deposition of mineral formations with bacteria produced together with oil and gas. The scale formation is predicted because the bacteria contained in petroleum are attached to the distribution pipe to form crystal clumps

Structural and Functional Distress Due to Slag Expansion

Cracking and heaving of a Single Storey R.C. Building was initially perceived as settlement. This error led to unnecessary and costly remedial measures such as Piling for the Phase ll Building which further aggravated the problem. The heaving was caused by a seemingly innocent decision during the construction stage to use Slag from a steel mill as the base course material. This Slag reacted with the highly corrosive groundwater which caused heaving of the Building and discomfort and morale problems to the Building occupants. Careful engineering study and investigation resulted in a very simple solution which saved the Building from abandonment and demolition

GEOTHERMAL EXPLORATION IN THE ALEXANDRIA AREA, THESSALONIKI BASIN (MACEDONIA, NORTHERN GREECE)

Η περιοχή της Αλεξάνδρειας βρίσκεται στη Λεκάνη Θεσσαλονίκης, η οποία έχει πληρωθεί με ιζήματα πάχους άνω των 4 km. To 1980, κατασκευάσθηκε βόρεια της πόλης της Αλεξάνδρειας η γεώτρηση έρευνας υδρογονανθράκων AL-1, βάθους 1705 m, στην οποία καταγράφηκαν οι θερμοκρασίες των 39 και 65oC σε βάθη 700 και 1705 m αντίστοιχα. Μεταξύ 1996 και 2000, ανορύχθηκαν δύο γεωθερμικές ερευνητικές γεωτρήσεις, βάθους 532 και 620 m, οι οποίες διέτρησαν Τεταρτογενή και Πλειοκαινικά ιζήματα και στις οποίες μετρήθηκαν θερμοκρασίες 30.1 και 33.4oC σε βάθη 500 και 611 m αντίστοιχα. Η προκαταρκτική γεωθερμική έρευνα οδήγησε την κατασκευή της πρώτης παραγωγικής γεώτρησης (ΓΝ-1Π). Ανορύχθηκε μέχρι βάθος 805 m διατρύοντας αργίλους, άμμους, τόφφους, μάργες, αργιλο-μάργες, μαργαϊκούς ασβεστόλιθους, χάλικες, ψαμμίτες και κροκαλοπαγή. Η γεώτρηση σωληνώθηκε μέχρι τα 805 m και φίλτρα τοποθετήθηκαν σε διάφορα βάθη κάτω από τα 607 m. Τιμές θερμοκρασίας και ηλεκτρικής αγωγιμότητας 35.1-37.2oC και 5100-8200 μS/cmαντίστοιχα καταγράφηκαν σε βάθη 607-800 m. Η γεώτρηση παρουσιάζει αρτεσιανή ροή με 30-40 m3/h νερών των 34.1oC και παρέχει με άντληση 130 m3/h νερών θερμοκρασίας 35.5oC. Το παραγόμενο γεωθερμικό νερό με ΣΔΑ 2.18 g/l είναι του τύπου Na-Cl και διαφοροποιείται από τα ρηχά νερά. Η θερμική ισχύς της γεώτρησης ΓΝ-1Π υπολογίζεται σε 1.65 MWt.The area of Alexandria is located in the Thessaloniki basin that has been filled with more than 4 km of sediments. In 1980, oil exploration borehole AL-1, 1,705 m deep, was drilled north of the town of Alexandria and the temperatures of 39 and 65oC were recorded at depths of 700 and 1,705 m respectively. During 1996-2000, two geothermal exploration boreholes were drilled at depths of 532 and 620 m penetrating Quaternary and Pliocene sediments and the temperatures of 30.1 and 33.4oC were measured at 500 and 611 m respectively. The preliminary geothermal investigation resulted in the construction of the first production well (GN-1P). It was drilled to a depth of 805 m penetrating clays, sands, tuffs, marls, clayey marls, marly limestones, gravels, sandstones and conglomerates. The borehole was cased down to 805 m and screens were placed at various depths below 607 m. Temperature and electrical conductivity values of 35.1-37.2oC and 5,100-8,200 μS/cm respectively were recorded at depths of 607-800 m. This well discharges 30-40 m3/h waters at 34.1oC with artesian flow and provides 130 m3/h waters at 35.5oC with pumping. The produced geothermal water with TDS of 2.18 g/l belongs to the Na-Cl type differentiated from the shallow waters. The thermal capacity of well GN-1P is calculated to be 1.65 MWt