Methodology of calculation of construction and hydrodynamic parameters of a foam layer apparatus for mass-transfer processes

Промислова реалізація методу стабілізації газорідинного шару дозволяє значно розширити галузь застосування пінних апаратів і відкриває нові можливості інтенсифікації технологічних процесів з одночасним створенням маловідходних технологій. У статті встановлені основні параметри, що впливають на гідродинаміку пінних апаратів, розглянуті основні конструкції та режими роботи пінних апаратів. Виявлено зв'язок гідродинамічних параметрів. Розглянуто гідродинамічні закономірності пінного шару. Вказані фактори, що впливають на процес масообміну, як в газовій, так і в рідкій фазах. Проведений аналіз ряду досліджень показав, що перспективним напрямком інтенсифікації процесу масообміну є розробка апаратів з трифазним псевдозрідженим шаром зрошуваної насадки складних форм із сітчастих матеріалів. Отже, необхідне проведення спеціальних досліджень гідродинамічних режимів роботи апарату з сітчастою насадкою і визначенням параметрів, що впливають на швидкість переходу насадки з одного режиму в інший.Industrial implementation of the stabilization method of the gas-liquid layer can significantly expand the field of use of foaming apparatus and opens up new opportunities for intensifying technological processes with the simultaneous creation of low-waste technologies. The article establishes the basic parameters influencing the hydrodynamics of foam apparatus, considers the basic constructions and operating modes of foam apparatus. The connection of hydrodynamic parameters is revealed. The hydrodynamic laws of the foam layer are considered. The indicated factors affecting the process of mass transfer, both in the gas and in the liquid phases. The conducted analysis of a number of studies showed that the perspective direction of intensification of the mass transfer process is the development of apparatuses with a three-phase fluidized bed of an irrigated nozzle of complex forms with mesh materials

Aneurysms—from traumatology to screening

This paper deals with aneurysmal disease, primarily when localized in the abdominal aorta. It is based on the Olof Rudbeck lecture 2009. Aneurysm is a localized widening of an artery, and its definition has become an important issue today when the disease is in focus for screening programmes. Aetiology and pathogenesis are still poorly understood, but a genetic component determining the strength of the aortic wall is important, and there is a strong male dominance. Historically, several attempts have been made to treat the disease, but reconstructive treatment has been possible only since 1951, in an increasing number of cases performed endovascularly. By early detection through screening, and thereby the possibility to treat before rupture, it has now become possible to decrease the total mortality from the disease in the population

Early and Intermediate Outcome of Emergency Endovascular Aneurysm Repair of Ruptured Infrarenal Aortic Aneurysm: A Single-Centre Experience of 90 Consecutive Patients

AbstractObjectiveTo evaluate the early and intermediate outcome of a consecutive series of emergency endovascular aneurysm repairs (eEVAR) of computed tomography (CT)-verified infrarenal ruptured abdominal aortic aneurysm (rAAA) at a single tertiary referral centre.MethodsProspectively collected data of patients operated between April 2000 and October 2007 were retrospectively reviewed and all their pre-, intra- and postoperative imaging were re-evaluated. Patient and procedural data were analysed using a Cox multiregression model.ResultsNinety patients (86% men, aged 76 (±7) years), were identified and included in the analysis. Symptom duration was <3h in 22% of patients, 3–24h in 39% and >24h in 39%. Mean aneurysmal diameter was 73 (±14)mm. All patients were treated with the COOK Zenith® stent-graft (56% bi-iliac and 44% uni-iliac). Sixty-one percent were haemodynamically unstable on presentation, and 26% required an intra-operative aortic occlusion balloon to maintain haemodynamic stability.The 30-day and 1-year mortality rates were 27% and 37%, respectively. One-year aneurysm-related mortality was 33%. Twenty-eight percent of patients required re-interventions during the follow-up. The use of an aortic occlusion balloon and the presence of cerebrovascular disease or obstructive lung disorder correlated significantly with 30-day mortality in the multivariate analysis.ConclusionEVAR is a valid treatment option for rAAA when used as a first-line method for all patients