Electrochemical recovery of zinc from the spent pickling baths coming from the hot dip galvanizing industry. Potentiostatic operation

An electrochemical reactor was developed to recover zinc from the spent pickling solutions coming from the hot dip galvanizing industry. These solutions mainly contain ZnCl2 and FeCl2 in aqueous HCl media. The effect of the applied potential on the figures of merit (fractional conversion, current efficiency, space-time yield and specific energy consumption) of the electrochemical reactor was analysed. Voltammetric experiments were performed previously in order to select the optimum conditions to be applied in the electrolysis experiments. From the I-V curves it was inferred that bulk zinc deposition started from potential values more cathodic than -0.99 V. The hydrogen evolution reaction (HER) appeared from -0.45 V and masked the zinc cathodic peak C1, related to bulk zinc deposition, at high HCl concentrations. The presence of HCl inhibited iron deposition in synthetic samples. The additives present in the real baths, which diminish the massive hydrogen generation, allowed the observation of peak C1. The potential values to be applied in the electrolysis experiments were chosen from the voltammetric experiments and ranged between -1 V and -1.75 V. In the absence of iron in solution, as the electrode potential was shifted towards more negative values, the space-time yield of zinc and its fractional conversion increased because of the increase in the electrode roughness and the hydrogen turbulence-promoting action. Simultaneously, the specific energy consumption decreased initially due to the increase in the zinc conversion rate but decreased for the most cathodic potential value due to HER. The presence of iron in synthetic solutions led to a decrease in current efficiency associated with the reverse redox Fe 2+/Fe3+ system and to the enhancement of the HER, which also induced increments in the local pH and the subsequent zinc redissolution for the most cathodic potential values. On the contrary, the additives present in the real spent pickling baths avoided the adverse effects of iron, and zinc electrodeposition was possible even at high cathodic potential values. In fact, a potential value of -1.75 V was selected as the optimum since the conversion, the current efficiency and the space time yield obtained in the real baths were relatively high.Authors want to express their gratitude to the Universidad Politecnica de Valencia for the economical support in the project reference PAID-06-08, and to the Generalitat Valenciana for the financing of the project reference GV/2010/029.Carrillo Abad, J.; García Gabaldón, M.; Ortega Navarro, EM.; Pérez-Herranz, V. (2011). Electrochemical recovery of zinc from the spent pickling baths coming from the hot dip galvanizing industry. Potentiostatic operation. Separation and Purification Technology. 81(2):200-207. https://doi.org/10.1016/j.seppur.2011.07.029S20020781

Recovery of zinc from spent pickling solutions using an electrochemical reactor in presence and absence of an anion-exchange membrane: Galvanostatic operation

The performance of a one- and two-compartment electrochemical reactor under galvanostatic control for zinc recovery present in the spent pickling solutions is studied in this paper. These solutions, which mainly contain ZnCl 2 and FeCl 2 in aqueous HCl media, come from the hot dip galvanizing industry. The effect of the anion-exchange membrane (AEM) on the figures of merit of the electrochemical reactor is analyzed. In the absence of iron in solution, as the current value was shifted towards more negative values, the zinc fractional conversion increased because of the increase in the zinc reduction rate. However, the increase in current values made current efficiency decrease due to the hydrogen-reduction side reaction, which caused an increment in the specific energy consumption. The presence of iron in synthetic solutions led to a decrease in current efficiency associated with the reverse redox Fe 2+/Fe 3+ system and to the enhancement of the HER, which also induced increments in the local pH and the subsequent zinc redissolution. These adverse effects related to the presence of iron could be minimized by the interposition of an AEM. In this case, the zinc redissolution was eliminated which enabled zinc conversion values close to 100% together with higher current efficiencies as the consumption of current by the system Fe 2+/Fe 3+ was diminished. © 2012 Elsevier B.V. All rights reserved.Authors want to express their gratitude to the Universidad Politecnica de Valencia for the economic support in the Project Reference PAID-06-08, and to the Generalitat Valenciana for the financing of the Project Reference GV/2010/029.Carrillo Abad, J.; García Gabaldón, M.; Ortega Navarro, EM.; Pérez-Herranz, V. (2012). Recovery of zinc from spent pickling solutions using an electrochemical reactor in presence and absence of an anion-exchange membrane: Galvanostatic operation. Separation and Purification Technology. 98:366-374. https://doi.org/10.1016/j.seppur.2012.08.006S3663749

Utilization of Smart Field concept in mature gas field rehabilitation

Since the concept of Smart Field emerged, the operating companies work hard to enable such capabilities through various technology developments, both in the field and the office. Smart Fields help to manage, deliver, optimize and develop short and long term decisions and plans. The technology of “Smart Fields” is based on the measurement of process parameters in the reservoir and on the surface [4]. Implementing Smart Gas Field help us to maximize the value of production and increase profitability, while reducing operating costs and the use of industrial services. The integrated and automated data from sensors, simulated models and controllers provide reliable diagnostic tests, enable measurable improvements and implement a favorable environment to plan and schedule phases of production [5]. The main challenge for Romgaz was to combine and integrate older system into newer one. The problem was the installed old technology equipment, which was difficult to replace by the new one. During the last years in the most majors fields has begun a process of rehabilitation. To extend the mature gas reservoir life we redeveloped and optimized the fields, improving productivity and reservoir performance. To aim these goals, today, we need monitoring / surveillance programs for optimizing the production . It is important to measure the parameters of process conditions as accurately as possible

Zmiana sposobu wiercenia otworu na dojrzałym złożu gazowym z wykorzystaniem przewodu o większej prędkości

In a gas field production decreases over time and can eventually stop producing completely because of liquid loading. As the reservoir pressure in a gas well depletes, there may be insufficient velocity to transport all liquids from the wellbore. In time, these liquids accumulate and impair production. The factors that are causing this problem include declining reservoir pressure, gas velocities and increased water production. One method of restoring a well that is liquid loaded back to flow production is installing a smaller diameter tubing string to run inside the production tubing of a well. Regarding advanced rate of depletion in Romgaz gas fields, reinjection method gives viable solutions to face the problems that appear in the exploitation of the wells with appreciable liquid impurities production.Z czasem produkcja na złożu gazowym ulega zmniejszeniu aż do całkowitego jej zaprzestania. Ciśnienie złożowe w otworach gazowych zmniejsza się powodując, że brak będzie siły wynoszącej płyny z otworu na zewnątrz. Z czasem płyny te kumulują się, uniemożliwiając dalszą produkcję. Czynnikami odpowiedzialnymi za te utrudnienia są obniżenie wartości ciśnienia złożowego, zmniejszone prędkości przepływu gazu oraz zwiększona produkcja wody. Jedną z metod stosowanych w przypadku otworów z reiniekcją jako sposobem na wymuszenie produkcji jest zastosowanie rur produkcyjnych o mniejszej średnicy wewnątrz rury wydobywczej. Metoda ta - iniekcji - jest skutecznym rozwiązaniem tego problemu w firmie ROMGAZ

Iodized oil as a complement to iodized salt in schoolchildren in endemic goiter in Romania

Objective: To evaluate the long-term efficacy and possible side effects of low doses of iodized oil on iodine nutrition and thyroid function in endemic goiter in Romania. Methods: Random selection of 214 schoolchildren aged 6-14 years. Serial measurements of urinary iodine, thyroid volume with ultrasound, serum concentrations of thyrotropin, free thyroxine, thyroglobulin and thyroid autoantibodies before and up to 2 years after the oral administration of 200 mg iodine in iodized oil. Results: Urinary iodine concentrations indicated a moderate iodine deficiency before therapy, sharply increased soon after therapy and slowly decreased thereafter but remained within the normal range up to more than 1 year after therapy. The prevalence of goiter was 29% before the administration of iodized oil and 9% 1 year later. Thyroid function tests and autoantibodies were normal before and up to 2 years after therapy. Conclusion: A single dose of 200 mg iodine from oral Lipiodol® appears adequate and safe for correcting moderate iodine deficiency in children. Copyright © 2002 S. Karger AG, Basel.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Incidental Papillary Thyroid Microcarcinoma: is Completion Surgery Required?

Rezumat Microcarcinomul papilar tiroidian descoperit incidental: este necesarã reintervenåia pentru completarea tirodectomiei? Introducere: Indicaåiile chirurgiei de completare la pacienåii cu microcarcinom papilar tiroidian (PMC) descoperit incidental pe piesa de tiroidectomie, dupã rezecåii pentru afecåiuni benigne, ramâne un subiect controversat. Metoda: Într-un studiu retrospectiv, transversal, de cohortã a 187 PMC, descoperite incidental în cursul examenului histopatologic al glandei tiroide, la 2168 pacienåi operaåi pentru afecåiuni tiroidiene benigne, am analizat influenåa tratamentului chirurgical iniåial aei al celui de completare asupra caracteristicilor anatomo-patologice asociate cu recidiva localã aei mortalitatea prin cancer tiroidian. Rezultate: La pacienåii cu tiroidectomie totalã sau aproape totalã la prima operatie, limfadenectomia ganglionilor suspecåi de malignitate la ultrasonografia postoperatorie a fost urmatã de o creaetere statistic semnificativã (p<0.01) a cazurilor cu metastaze ganglionare la examenul anatomopatologic. Chirurgia de completare efectuatã la 38 din cei 42 pacienåi cu lobectomie sau tiroidectomie subtotalã la prima intervenåie chirurgicalã nu a fost urmatã de o creaetere semnificativã a numãrului sau mãrimii tumorilor, multifocalitãåii, bilateralitãåii, invaziei extratiroidiene sau metastazelor ganglionare. În privinåa complicaåiilor postoperatorii, nu au fost diferenåe statistic semnificative între cele douã grupuri de pacienåi. Concluzii: La pacienåii cu lobectomie sau tiroidectomie subtotalã aei PMC descoperite incidental pe piesa de rezecåie, având dimensiuni 1-5 mm aei fãrã invazie extratiroidianã, chirurgia de completare nu a fost urmatã de o creaetere semnificativã a caracteristicilor patologice asociate cu morbiditatea aei mortalitatea prin cancer tiroidian. Cuvinte cheie: microcarcinom papilar tiroidian, tiroidectomie de completare, limfadenectomie Abstract Background: The indications for completion surgery in patients with thyroid papillary microcarcinoma (PMC), incidentally found in thyroids removed for benign conditions, remains a subject of debate. Methods: In a retrospective, transversal, cohort study of 187 incidental PMCs, found during histological examination of the thyroid gland in 2168 patients operated for benign thyroid conditions, we evaluated the influence of initial and completion surgery on pathological features associated to local recurrence and cancer-related mortality. Results: In the patients with almost total or total thyroidectomy at the first operation, lymphadenectomy of lymph nodes with features suggestive of malignancy on postoperative ultrasound resulted in a statistically significant (p<0.01) increase of node positive patients in pathological examination. thyroidectomy doesn't result in a significant increase of tumor size, number, multifocality, bilaterality, invasion or nodal metastases. There were no significant differences in postoperative complications between the two groups. Conclusions: In patients with less than total thyroidectomy and incidentally found PMC in resection specimens, 1-5 mm in greatest dimension and without extrathyroidal extension, completion surgery was not followed by a significant increase of pathological features associated to cancer related morbidity and mortality

Thyroid volume and urinary iodine in European schoolchildren: standardization of values for assessment of iodine deficiency

Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible changes in the status of iodine nutrition in 12 European countries during the past few years. Thyroid volume was measured by ultrasonography in 7599 schoolchildren aged 7-15 years in one to fifteen sites in The Netherlands. Belgium, Luxemburg, France, Germany, Austria, Italy, Poland, the Czech and Slovak Republics, Hungary and Romania. The concentrations of urinary iodine were measured in 5709 of them. A mobile unit (ThyroMobil van) equipped with a sonographic device and facilities for the collection of urine samples visited all sites in the 12 countries. All ultrasounds and all urinary iodine assays were performed by the same investigators. The status of iodine nutrition in schoolchildren has markedly improved in many European countries and is presently normal in The Netherlands, France and Slovakia. It remains unchanged in other countries such as Belgium. There is an inverse relationship between urinary iodine and thyroid volume in schoolchildren in Europe. Goiter occurs as soon as the urinary iodine is below a critical threshold of 10 micrograms/dl. Its prevalence is up to 10 to 40% in some remote European areas. This work produced updated recommendations for the normal volume of the thyroid measured by ultrasonography as a function of age, sex and body surface area in iodine-replete schoolchildren in Europe. This study proposes a method for a standardized evaluation of iodine nutrition on a continental basis, which could be used in other continent

Thyroid volume and urinary iodine in European schoolchildren: standardization of values for assessment of iodine deficiency.

Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible changes in the status of iodine nutrition in 12 European countries during the past few years. Thyroid volume was measured by ultrasonography in 7599 schoolchildren aged 7-15 years in one to fifteen sites in The Netherlands. Belgium, Luxemburg, France, Germany, Austria, Italy, Poland, the Czech and Slovak Republics, Hungary and Romania. The concentrations of urinary iodine were measured in 5709 of them. A mobile unit (ThyroMobil van) equipped with a sonographic device and facilities for the collection of urine samples visited all sites in the 12 countries. All ultrasounds and all urinary iodine assays were performed by the same investigators. The status of iodine nutrition in schoolchildren has markedly improved in many European countries and is presently normal in The Netherlands, France and Slovakia. It remains unchanged in other countries such as Belgium. There is an inverse relationship between urinary iodine and thyroid volume in schoolchildren in Europe. Goiter occurs as soon as the urinary iodine is below a critical threshold of 10 micrograms/dl. Its prevalence is up to 10 to 40% in some remote European areas. This work produced updated recommendations for the normal volume of the thyroid measured by ultrasonography as a function of age, sex and body surface area in iodine-replete schoolchildren in Europe. This study proposes a method for a standardized evaluation of iodine nutrition on a continental basis, which could be used in other continents