Successful Selection And Operation Of Gas Turbine Inlet Filtration Systems

Tutorialpg. 254-268A gas turbine inlet filtration system is important for successful operation. The filtration system minimizes the occurrence of foreign object damage, erosion, fouling, and corrosion. The selection of the inlet filtration system is a challenging process which involved choosing multiple filtration stages based on the desired performance of the gas turbine and the local operating environment. This tutorial walks through the factors that should be considered when selecting an inlet filtration system: 1) The characteristics of filters and filter systems, 2) A review of the many types of filters, 3) A detailed look at the different environments where the gas turbine can operate, 4) A process for evaluating the site where the gas turbine will be or is installed, and 5) A method to compare various filter system options with life cycle cost analysis

Technology Review of Modern Gas Turbine Inlet Filtration Systems

An inlet air filtration system is essential for the successful operation of a gas turbine. The filtration system protects the gas turbine from harmful debris in the ambient air, which can lead to issues such as FOD, erosion, fouling, and corrosion. These issues if not addressed will result in a shorter operational life and reduced performance of the gas turbine. Modern day filtration systems are comprised of multiple filtration stages. Each stage is selected based on the local operating environment and the performance goals for the gas turbine. Selection of these systems can be a challenging task. This paper provides a review of the considerations for selecting an inlet filtration system by covering (1) the characteristics of filters and filter systems, (2) a review of the many types of filters, (3) a detailed look at the different environments where the gas turbine can operate, (4) a process for evaluating the site where the gas turbine will be or is installed, and (5) a method to compare various filter system options with life cycle cost analysis

Technology Review of Modern Gas Turbine Inlet Filtration Systems

An inlet air filtration system is essential for the successful operation of a gas turbine. The filtration system protects the gas turbine from harmful debris in the ambient air, which can lead to issues such as FOD, erosion, fouling, and corrosion. These issues if not addressed will result in a shorter operational life and reduced performance of the gas turbine. Modern day filtration systems are comprised of multiple filtration stages. Each stage is selected based on the local operating environment and the performance goals for the gas turbine. Selection of these systems can be a challenging task. This paper provides a review of the considerations for selecting an inlet filtration system by covering (1) the characteristics of filters and filter systems, (2) a review of the many types of filters, (3) a detailed look at the different environments where the gas turbine can operate, (4) a process for evaluating the site where the gas turbine will be or is installed, and (5) a method to compare various filter system options with life cycle cost analysis

Racial/ethnic disparities in annual mammogram compliance among households in Little Haiti, Miami-Dade County, Florida

Abstract Introduction Breast cancer is the most commonly diagnosed cancer and the 2nd leading cause of cancer-related deaths among women in the U.S. Although routine screening via mammogram has been shown to increase survival through early detection and treatment of breast cancer, only 3 out of 5 women age ?40 are compliant with annual mammogram within the U.S. and the state of Florida. A breadth of literature exists on racial/ethnic disparities in compliance with mammogram; however, few such studies include data on individual Black subgroups, such as Haitians. This study assessed the association between race/ethnicity and annual mammogram compliance among randomly selected households residing in the largely Haitian community of Little Haiti, Miami-Dade County (MDC), Florida. Methods This study used cross-sectional, health data from a random-sample, population-based survey conducted within households residing in Little Haiti between November 2011 and December 2012 (n = 951). Mammogram compliance was defined as completion of mammogram by all female household members within the 12 months prior to the survey. The association between mammogram compliance and race/ethnicity was assessed using binary logistic regression models. Potential confounders were identified as factors that were conservatively associated with both compliance and race/ethnicity (P???0.20). Analyses were restricted to households containing at least 1 female member age ?40 (n = 697). Results Overall compliance with annual mammogram was 62%. Race/ethnicity was significantly associated with mammogram compliance (P = 0.030). Compliance was highest among non-Hispanic Black (NHB) households (75%), followed by Hispanic (62%), Haitian (59%), and non-Hispanic White (NHW) households (51%). After controlling for educational level, marital status, employment status, the presence of young children within the household, health insurance status, and regular doctor visits, a borderline significant disparity in mammogram compliance was observed between Haitian and NHB households (adjusted odds ratio = 1.63, P = 0.11). No other racial/ethnic disparities were observed. Discussion Compliance with annual mammogram was low among the surveyed households in Little Haiti. Haitian households underutilized screening by means of annual mammogram compared with NHB households, although this disparity was not significant. Compliance rates could be enhanced by conducting individualized, mammogram screening-based studies to identify the reasons behind low rate of compliance among households in this underserved, minority population

Centrifugal Compressor Rotordynamics in Wet Gas Conditions

LectureA new technology challenge in centrifugal compressor design and operation is the condensate phase management. End users (especially in offshore and subsea operations) are more and more interested to have a Wet Gas Compression system which is able to tolerate liquid in the process gas. Authors’ Company has initiated for several years a research program aiming to investigate the impact of the liquid phase on centrifugal compressor operability (mainly thermodynamics, rotordynamics, erosion, axial thrust). As an introduction, the Authors’ Company past experiences and more recent experimental tests [Ransom D. et al. 2011], [Bertoneri M. et al. 2012], are reviewed in order to show how the rotordynamic behaviour of a centrifugal compressor may be affected by the wet gas. However in the core, this paper is focused on the novel rotordynamic experimental outcomes of a wet gas single stage compressor test campaign. The machine was equipped with the following special instrumentation: Pressure and temperature probes along the flow path and internal seals; Magnetic lamination installed on the shaft end to allow for stability test through a magnetic exciter; Load cells installed in the thrust bearing; Torquemeter installed at the compressor coupling. The explored test conditions were: Wet gas = Air and Water mixture up to 3% of Liquid Volume Fraction (LVF); Suction pressure levels = 10, 15, 20 bar-a; Maximum Continuous Speed = 13500 rpm. The compressor went through an extensive test campaign where the following aspects were thoroughly investigated: Rotordynamic behaviour during steady state wet operation; Rotordynamic stability (through magnetic exciter); Transient phenomena: response to liquid load variations (LVF up to 8%), start-up/shutdown from wet conditions, start-up with stratified flow into suction pipe. The compressor dynamic behaviour was monitored both from lateral viewpoint (using no contact probes located close to bearing locations) and axial/torsional viewpoint (through the special instrumentation described above). Overall the compressor was able to withstand a huge amount of liquid phase, with an increased vibration level with respect to dry conditions but still in the safe area, both in steady and transient tests. Finally, major differences were found only at high flow – high liquid/gas density ratio conditions where an unexpected subsynchronous vibration (SSV) was showing up. The nature of this SSV was deeply investigated and finally it was fixed through a balance piston seal geometry change

Discriminative Stimulus Effects of Magnesium Chloride: Substitution Studies with Monoamine Uptake Inhibitors and N-Methyl-D-Aspartate Antagonists 1

ABSTRACT Previous studies suggest that magnesium chloride may have discriminative stimulus effects that partially overlap with those of noncompetitive N-methyl-D-aspartate antagonists as well as certain monoamine uptake inhibitors. In our study, rats were trained to discriminate 100 mg/kg magnesium chloride from saline and its discriminative stimulus effects were characterized with respect to N-methyl-D-aspartate receptor and monoamine transporter functions in substitution tests. The discriminative stimulus effects of magnesium chloride were acquired within a moderate number of training sessions and showed dose-related substitution after either subcutaneous (3-300 mg/kg) or intracerebroventricular (0.3-300 g) administration. The intracerebroventricular administration of magnesium chloride was over 4000 times more potent than its s.c. administration. The monoamine uptake inhibitors cocaine, GBR 12909, talsupram and citalopram fully substituted (Ն90% magnesium-appropriate responses) for magnesium chloride in the majority of subjects tested and the group averages reached a maximum of 72 to 82% responses on the magnesium-appropriate lever. Based on relative potency analysis, the rank order of potency of these four drugs for producing magnesium-appropriate responses was talsupram ϭ cocaine Ͼ citalopram ϭ GBR 12909. The N-methyl-D-aspartate receptor antagonists dizocilpine, phencyclidine and NPC 17742 engendered maximum group averages of 49 to 65% responses on the magnesium-appropriate lever. The results suggest that the centrally mediated discriminative stimulus effects of magnesium chloride may be more directly related to interactions with monoamine neurotransmitter functions than to N-methyl-D-aspartate receptor blockade

Surge and Surge Control Systems

Short Cours

Mechanical Performance Of A Two Stage Centrifugal Compressor Under Wet Gas Conditions

Lecturepg. 121-128As subsea compression becomes a vital technology to the successful production of gas reserves in the North Sea, several technology issues will come to the forefront of the oil and gas industry. One of these important subjects is the capability to compress gas which includes a significant amount of liquids. Compressing wet gas requires knowledge in areas such as the prediction of turbomachinery performance with the mixed phase flow as well as the mechanical reliability of machinery in the same environment. This paper presents experimental results from a wet gas test campaign which, among other goals, is focused on characterizing the mechanical performance of a two stage compressor operating under wet gas conditions. Various mechanical parameters are monitored in the test program including rotor radial and axial vibration, rotor thrust, and shaft torque. A full array of wet gas conditions are tested with a suction pressure of 20 bar (300 psia) and liquid volume fractions in the range of 0.5 to 5%. The operating fluids are air and water, and the two stage compressor is operated at three speed lines ranging from high flow to low flow conditions. Significant variations are noted in the axial thrust, axial vibration and shaft torque. Thrust variations range from seemingly neutral thrust conditions at very low water injection rates to significant thrust increases (as compared to dry condition) for very high water injection rates. Rotor axial vibration is characterized by large amplitude and very low frequency, especially for the case in which the rotor thrust is balanced by the water injection. During higher levels of water injection, rotor axial vibration is generally characterized by relatively large amplitude and slightly higher frequency, although still very low as a percent of running speed. Variations in radial vibration are also noted, but to a much lesser extent

Strategic considerations for invasive species managers in the utilization of environmental DNA (eDNA): Steps for incorporating this powerful surveillance tool

Invasive species surveillance programs can utilize environmental DNA sampling and analysis to provide information on the presence of invasive species. Wider utilization of eDNA techniques for invasive species surveillance may be warranted. This paper covers topics directed towards invasive species managers and eDNA practitioners working at the intersection of eDNA techniques and invasive species surveillance. It provides background information on the utility of eDNA for invasive species management and points to various examples of its use across federal and international programs. It provides information on 1) why an invasive species manager should consider using eDNA, 2) deciding if eDNA can help with the manager’s surveillance needs, 3) important components to operational implementation, and 4) a high-level overview of the technical steps necessary for eDNA analysis. The goal of this paper is to assist invasive species managers in deciding if, when, and how to use eDNA for surveillance. If eDNA use is elected, the paper provides guidance on steps to ensure a clear understanding of the strengths and limitation of the methods and how results can be best utilized in the context of invasive species surveillance