Mixing characteristics of bubble columns with internals for Biomass to liquid synthesis [abstract]

Only abstract of poster available.Track II: Transportation and BiofuelsThe use of renewable energy sources is becoming increasingly necessary, if we are to achieve the changes required to address the impacts of global warming. Biomass is the most common form of renewable energy, widely used in the third world but until recently, less so in the Western world. Latterly much attention has been focused on the conversion of biomass to liquid fuels; a process which would greatly increases the potential usefulness of biomass as a renewable resource. Conversion of biomass to liquid is carried out by first gasification of biomass to yield synthetic gas. The synthetic gas can then be converted to liquid fuels using Fischer Tropsch process or transformed to methanol for subsequent use as a chemical, solvent or fuel. For large-scale FT / methanol synthesis the slurry bubble column reactor is the best choice. These reactors offer high conversion and high volumetric productivity when operated in the heterogeneous or churn turbulent regime. Notwithstanding the presence of large diameter bubbles and their short residence time in the liquid, gas-liquid mass transfer is quite fast in this regime due to the effective interaction between bubbles of various sizes. However, despite the simple construction and operation of bubble columns, their scale-up is very difficult due to complex interrelations among the many parameters that determine the behavior of bubble columns. In addition the complexity increases with the presence of cooling internals that affect the hydrodynamics and mixing behavior in bubble columns. Gas phase backmixing is one of the important hydrodynamic parameters to be considered in the scale-up of bubble columns as it can adversely affect the reaction rates and product selectivity. The present investigation focuses on studying the effect of the cooling internals on gas phase mixing behavior. The percentage of internals used in this study is the same percentage used industrially for methanol synthesis (5 % internals) and FT synthesis (25% internals)

Advancement of TRISO Nuclear Fuel Coaters for High Temperature Pebble Bed Nuclear Reactors: Environmentally Benign and Risk Free Proliferation 4th Generation Nuclear Energy [abstract]

Only abstract of poster available.Track I: Power GenerationThe success on nuclear energy produced by advanced high temperature gas reactors (AGRs) is dependent on tri-isotropic (TRISO) fuel particle coating. Today modern AGRs require essentially zero defective/failed coated particles. Unfortunately, the scale-up and design of the current coating processes using gas-solid spouted beds have been based on empirical approaches and are operated as “black boxes” due to lack of fundamental understanding of the hydrodynamics of spouted bed coaters. Further complicating future fuel-coating technology and nuclear energy production is the fact that fuel kernels of different sizes and densities are required to be manufactured. Therefore, in order to prevent the large risk associated with producing particles that do not meet the specifications, a fundamental understanding of the phenomena occurring in the spouted bed TRISO coater is needed. Accordingly, the overall research objectives of this project are 1) to advance the fundamental understanding of the hydrodynamics TRISO fuel coaters by systematically investigating the effect of design and operating variables, 2) to evaluate the reported dimensionless groups as scaling factors, 3) to establish a reliable scale-up methodology for TRISO fuel particle spouted bed coaters based on hydrodynamics similarity via advanced measurement and computational techniques, and 4) to develop an on-line, non-invasive measurement technique based on gamma ray densitometry (i.e., Nuclear Gauge Densitometry) that can be installed for industrial coater process monitoring to ensure proper performance and operation and to facilitate the developed scale-up methodology. To achieve these objectives the following research tools will be implemented and/or developed: • Optical probes for solid and gas holdup and solids velocity distribution measurements. • Gamma ray computed tomography (CT) for measuring the solid and gas holdup cross-sectional distribution along the spouted bed height, spouted diameter, and fountain height. • Radioactive particle tracking (RPT) technique for measuring the 3D flow patterns and field, solids velocity, turbulent parameters, circulation time, and many others. • Gas dynamics measurement technique. • Pressure transducers. In this presentation, the results and findings that are so far obtained with will be discussed and the work in progress will be outlined

Occupational characteristics of cases with asbestos-related diseases in The Netherlands

OBJECTIVE: To describe the occupational background of cases with an asbestos-related disease and to present overall mesothelioma risks across industries with historical exposure to asbestos. METHODS: For the period 1990-2000, cases were collected from records held by two law firms. Information on jobs held, previous employers, activities performed and specific products used were obtained from patients themselves or next of kin. Branches of industry and occupations were coded and the likelihood of asbestos exposure was assessed. For each branch of industry, the overall risk of mesothelioma was calculated from the ratio of the observed number of mesothelioma cases and the cumulative population-at-risk in the period 1947-1960. In order to compare mesothelioma risks across different industries, risk ratios were calculated for the primary asbestos industry and asbestos user industries relative to all other branches of industry. RESULTS: In total, 710 mesotheliomas and 86 asbestosis cases were available. The average latency period was approximately 40 yr and the average duration of exposure was 22 yr. Ship building and maintenance contributed the largest number of cases (27%), followed by the construction industry (14%), the insulation industry (12%), and the navy and army, primarily related to ship building and maintenance (5%). In the insulation industry, the overall risk of mesothelioma was 5 out of 100 workers, and in the ship building industry, 1 out of 100 workers. The construction industry had an overall risk comparable with many other asbestos-using industries (7 per 10,000 workers), but due to its size claimed many mesothelioma cases. CONCLUSION: The majority of cases with asbestos-related diseases had experienced their first asbestos exposure prior to 1960. For cases with first asbestos exposure after 1960, a shift was observed from the primary asbestos industry towards asbestos-using industries, such as construction, petroleum refining, and train building and maintenance. Due to the long latency period, asbestos exposure from 1960 to 1980 will cause a considerable number of mesothelioma cases in the next two decades

How could multimedia information about dental implant surgery effects patients? anxiety level?

To evaluate the effects of different patient education techniques on patients? anxiety levels before and after dental implant surgery. Sixty patients were randomized into three groups; each contained 20 patients; [group 1, basic information given verbally, with details of operation and recovery; group 2 (study group), basic information given verbally with details of operative procedures and recovery, and by watching a movie on single implant surgery]; and a control group [basic information given verbally ?but it was devoid of the details of the operative procedures and recovery?]. Anxiety levels were assessed using the Spielberger?s State-Trait Anxiety Inventory (STAI) and Modified Dental Anxiety Scale (MDAS). Pain was assessed with a visual analog scale (VAS). The most significant changes were observed in the movie group (P < 0.05). Patients who were more anxious also used more analgesic medication. Linear regression analysis showed that female patients had higher levels of anxiety (P < 0.05). Preoperative multimedia information increases anxiety level

Fundamental Understanding of Pebble Bed Nuclear Reactors for Environmentally Benign and Risk Free Proliferation 4th Generation Nuclear Energy and Hydrogen Production [abstract]

Abstract only availableTrack I: Power GenerationPebble bed nuclear reactor is among the 6 suggested 4th generation nuclear reactors. It is also one of the advanced high temperature gas nuclear reactors (AGRs). In such reactor the pebbles that contain the nuclear fuel particles (TRISO) (~900-950 micron) move downward while high temperature helium moves upward. These pebbles are circulated until they are spent. The pebble bed nuclear reactors are characterized as environmentally benign, risk free proliferation with high thermal efficiency (about 55% while the current nuclear reactor technology provides ~ 35%). The fundamental understanding of these reactors is lacking. Therefore, this work as a part of the research program on high temperature reactors through the consortium consists of University of Missouri - Columbia, Missouri S&T, North Carolina State University focuses on the detailed hydrodynamics of the pebbles movement, gas dynamics and heat transfer using both advanced measurement and computation techniques. The progress made on this project at Missouri S&T will be presented and the future work will be outlined

A Research Program on Very High Temperature Reactors

Track I: Power GenerationIncludes audio file (27 min.)Prismatic and pebble bed very high-temperature reactors (VHTRs) are very attractive both from a thermodynamic efficiency viewpoint and hydrogen-production capability. This project addresses numerous challenges associated with the fuel cycle, materials, and complex fluid dynamics and heat transfer. The objectives of the project are to: i. Conduct physical experiments for fission product transport phenomena in the overcoating and compact structural graphite and transport through TRISO coating layers; ii. Develop improved sorption measurement techniques to measure the accumulation of condensable radionuclides (“plateout”) in the VHTR primary coolant circuit and obtain representative data; iii. Develop advanced computations of charged, radioactive dust (aerosol) transport in the VHTR coolant circuit and confinement by exploring direct simulation Monte Carlo (DSMC) techniques for deposition and resuspension and conduct experiments to verify computational predictions; iv. Develop a program to measure emissivity for various VHTR component materials, both bare and oxidized, and obtain extensive data; v. Develop an experimental program to characterize gas, fission product, and particle flows in the complex geometries of pebble bed modular reactors (PBMRs) and help improve computational approaches and computer programs through experimental understandings. This project is leading to research training of about a dozen Ph D students at the participating universities. Upon graduation, these students will be able to contribute even more effectively to the future challenges in the global deployment of nuclear power generation and hydrogen technologies. We will discuss the VHTR technology and research challenges. We also describe progress on the project by the three Consortium participants

Development of Kinetic and Process Models for the Oxidative Desulfurization of Light Fuel, Using Experiments and the Parameter Estimation Technique

YesThe oxidative desulphurization (ODS) of light gas oil (LGO) is investigated with an in-house designed cobalt 11 oxide loaded on alumina (γ-Al2O3) catalyst in the presence of air as oxidizing agent under moderate operating 12 conditions (temperature from 403 to 473 K, LHSV from 1 to 3 hr-1, initial concentration from 500 to 1000 13 ppm). Incipient Wetness Impregnation method (IWI) of cobalt oxide over gamma alumina (2% Co3O4/γ-14 Al2O3) is used for the preparation of the catalyst. The optimal design of experiments is studied to evaluate the 15 effects of a number of process variables namely temperature, liquid hourly space velocity (LHSV) and 16 concentration of dibenzothiophene and their optimal values were found to be 473 K, 1hr-1 and 1000 ppm 17 respectively. For conversion dibenzothiophene to sulphone and sulphoxide, the results indicates that the 18 Incipient Wetness Impregnation (IWI) is suitable to prepare this type of the catalyst. Based on the 19 experiments, mathematical models that represent a three phase reactor for describing the behavior of the ODS 20 process are developed. 21 In order to develop a useful model for simulation, control, design and scale-up of the oxidation process, 22 accurate evaluation of important process parameters such as reaction rate parameters is absolutely essential. 23 For this purpose, the parameter estimation technique available in gPROMS (general Process Modelling 24 System) software is employed in this work. With the estimated process parameters further simulations of the 25 process is carried out and the concentration profiles of dibenzothiophene within the reactor are generated

Evaluation of ADA, IL-6 and TNF-alpha level in type 2 diabetes mellitus: with -and without hypoglycemic drugs.

Diabetes mellitus(DM) is a major worldwide  health problem leading to markedly increase mortality and serious morbidity. Immunological disturbances involving the cell mediated immune system and improper T-lymphocyte function also contribute to the path physiology of type 2 DM.It has been reported that ADA,IL-6,and TNF-α levels  were a good marker for immunological disturbance in type 2 DM  patients.This study aims to assess and compare the level of serum ADA, IL-6 ,and TNF-α in patient of type 2 DM with and without oral hypoglycamic drugs.The study population consist of 150 subjects divided in to 3 groups:group I (50normal health controls),group II (45 type 2 DM patients with no on hypoglycemic drugs),and group Ш (55 type 2 DM patients on hypoglycemic drugs).There were a significant(p&lt;0.001) tremendous increase in ADA,IL-6,and TNF-α levels (47.32 U/L ,29.04 pg/ml ,and 98.23 pg/ml, respectively ) in group II  than group I and group Ш. also, ADA,IL-6,and TNF-α levels were significantly(p&lt;0.001) higher in group Ш than group I.As conclusion ,the increase in ADA,IL-6,and TNF-α levels  is a good glycemic  markers associated with type 2 DM .The intake of hypoglycaemic drugs  decrease the levels of these markers. Key words: ADA activity , IL-6 , TNF-α , type 2 diabetes mellitus

Bio-Energy Production from Anaerobic Digestion of Animal and Farm Wastes

Track II: Transportation and BiofuelsIncludes audio file (20 min.)US produces annually huge amount of animal and farm wastes (e.g. only cow manure in amount of about 1.8 billion tons). These wastes can be valuable source of renewable energy besides overcoming the environmental problems caused by them such as greenhouse gas effect of methane emission of 22 times worse than carbon dioxide, surface and ground water contamination, odor, dust, ammonia leaching, etc. In this project we systematically studied the process, kinetics, microorganisms interaction and population, and the effects of design and operating parameters on reactor design and scale up of cow manure digestion for bioenergy production and for wastes treatment by developing and implementing advanced imaging, visualization and computational techniques such as computational fluid dynamics (CFD), novel multiple radioactive particles tracking technique (MRPT), novel dual source computed tomography (DSCT), and microbiology imaging techniques. New design and conditions of anaerobic digesters that can reduce significantly the inactive volume and improve the digesters performance have been identified and recommended. In addition, for the first time, the energy produced has been related to the energy introduced in order to maximize the energy output while minimizing the energy input through the mixing power consumed. It is hoped that the findings will be applied in the field to promote bioenergy production and eliminate major environmental pollution problems