267 research outputs found
Bulk Solids Handling Fundamentals
Identifying the lines or equipment that handle solids in a chemical plant is easy: they\u27re the ones with all the hammer marks. Although chemical engineers possess the education and experience to design or recommend systems for handling liquids and gases, their training on the principles that describe the flow of bulk solids is sometimes lacking in comparison.
This seminar will discuss how the fundamental properties of bulk solids, including cohesive strength, wall friction, permeability, and compressibility, can be used to predict if and how bulk materials will flow and how to design systems for reliable flow
Renewable Energy
This chapter presents an in-depth examination of major renewable energy technologies, including their installed capacity and energy supply in 2009 , the current state of market and technology development, their economic and financial feasibility in 2009 and in the near future,
as well as major issues they may face relative to their sustainability
or implementation. Renewable energy sources have been important for humankind since the beginning of civilization. For centuries, biomass has been used for heating, cooking, steam generation, and power production;
solar energy has been used for heating and drying; geothermal energy has been used for hot water supplies; hydropower, for movement;
and wind energy, for pumping and irrigation. For many decades renewable energy sources have also been used to produce electricity or
other modern energy carriers
Recommended from our members
Session: CSP Advanced Systems -- Advanced Overview
The project description is: (1) it supports crosscutting activities, e.g. advanced optical materials, that aren't tied to a single CSP technology and (2) it supports the 'incubation' of new concepts in preliminary stages of investigation
Optimal coupling of waste and concentrated solar for the constant production of electricity over a year
[EN]In this paper a biogas-based Brayton cycle is integrated with a concentrated solar power facility. The gas turbine hot flue gas and the molten salts are used to generate steam for the regenerative Rankine cycle. The process model is solved as a non-linear optimization problem within a multiperiod scheme to decide on the contribution of the energy resources and the operating conditions of the facility to meet a certain demand of power over a year mitigating the absence of solar availability. The steam turbine is responsible for power production while the gas turbine works mainly as a combustion chamber. In the South of Spain an excess of biogas is available during summer yielding a production cost of electricity of 0.17€/kWh with an investment of 380 M€ for a production facility of 25MW. This plant is not yet economic
Analysis of Concentrating Solar Power with Thermal Energy Storage in a California 33% Renewable Scenario
This analysis evaluates CSP with TES in a scenario where California derives 33% of its electricity from renewable energy sources. It uses a commercial grid simulation tool to examine the avoided operational and capacity costs associated with CSP and compares this value to PV and a baseload generation with constant output. Overall, the analysis demonstrates several properties of dispatchable CSP, including the flexibility to generate during periods of high value and avoid generation during periods of lower value. Of note in this analysis is the fact that significant amount of operational value is derived from the provision of reserves in the case where CSP is allowed to provide these services. This analysis also indicates that the 'optimal' configuration of CSP could vary as a function of renewable penetration, and each configuration will need to be evaluated in terms of its ability to provide dispatchable energy, reserves, and firm capacity. The model can be used to investigate additional scenarios involving alternative technology options and generation mixes, applying these scenarios within California or in other regions of interest
Acciona Solar Technology Performance Evaluation: Cooperative Research and Development Final Report, CRADA Number CRD-10-384
Under this agreement, NREL will work with Acciona to conduct joint testing, evaluation, and data collection related to Acciona's solar technologies and systems. This work includes, but is not limited to, testing and evaluation of solar component and system technologies, data collection and monitoring, performance evaluation, reliability testing, and analysis. This work will be conducted at Acciona's Nevada Solar One (NSO) power plant and NREL test facilities. Specific projects will be developed on a task order basis. Each task order will identify the name of the project and deliverables to be produced under the task order. Each task order will delineate an estimated completion date based on a project's schedule. Any reports developed under this CRADA must be reviewed by both NREL and Acciona and approved by each organization prior to publication of results or documents
Enabling Greater Penetration of Solar Power via the Use of CSP with Thermal Energy Storage
At high penetration of solar generation there are a number of challenges to economically integrating this variable and uncertain resource. These include the limited coincidence between the solar resource and normal demand patterns and limited flexibility of conventional generators to accommodate variable generation resources. Of the large number of technologies that can be used to enable greater penetration of variable generators, concentrating solar power (CSP) with thermal energy storage (TES) presents a number of advantages. The use of storage enables this technology to shift energy production to periods of high demand or reduced solar output. In addition, CSP can provide substantial grid flexibility by rapidly changing output in response to the highly variable net load created by high penetration of solar (and wind) generation. In this work we examine the degree to which CSP may be complementary to PV by performing a set of simulations in the U.S. Southwest to demonstrate the general potential of CSP with TES to enable greater use of solar generation, including additional PV
Pharmacy Care and Adherence to Primary and Secondary Prevention Cardiovascular Medication- A systematic review of studies
Objective To determine if pharmacy service intervention can lead to enhanced adherence to primary and secondary cardiovascular medication and to identify features of interventions that have been found to be effective and feasible.
Methods A systematic search of studies related to pharmacy service interventions on adherence and outcomes of cardiovascular diseases was performed using the following databases: PubMed Central UK, PubMed, Cochrane Library, CINHAL, PsycINFO, EMBASE, International Pharmaceutical Abstracts and Google Scholar for the period from 1 January 1990 to 19 November 2013. Trials were included if they were randomised control trials, studies delivered in hospital or community settings, and studies in English language. A hand search of relevant citations was also performed.
Key findings Forty-two studies were identified of which 26 had a statistically significant effect on adherence and twenty-seven had a significant effect on clinical outcomes of cardiovascular disease. The interventions included mainly patient education, collaboration between healthcare professionals, use of electronic devices and combined interventions. The interventions were found to be complex and included multiple components. Patient contact with a pharmacist was frequent and thus the interventions may be difficult to adapt to daily practice. Evidence-based data for pharmacy services remain weak but clearly pharmacists can have an impact through face-to-face patient education and telephone consultations. Further research is needed to evaluate the use of a motivational interview in the counselling session of a pharmacist and also to establish the continuity of pharmacy care in primary/secondary setting. Self-reported adherence was the most widely used measure. The acceptable threshold remained 80% among the cardiac population.
Conclusion Pharmacist interventions have been shown to be successful in enhancing adherence to cardiovascular medication and improving outcomes of cardiovascular diseases. Whilst pharmacists play a fundamental role in primary and secondary prevention strategies, further randomised controlled trials combining patient education with behaviour change are likely to reap further benefit in medication adherence
Interventions used to improve control of blood pressure in patients with hypertension.
BACKGROUND: It is well recognized that patients with high blood pressure (hypertension) in the community frequently fail to meet treatment goals - a condition labeled as "uncontrolled" hypertension. The optimal way in which to organize and deliver care to patients who have hypertension so that they reach treatment goals has not been clearly identified. OBJECTIVES: To determine the effectiveness of interventions to improve control of blood pressure in patients with hypertension. To evaluate the effectiveness of reminders on improving the follow-up of patients with hypertension. SEARCH STRATEGY: All-language search of all articles (any year) in the Cochrane Controlled Trials Register (CCTR), Medline and Embase from June 2000. SELECTION CRITERIA: Randomized controlled trials (RCTs) of patients with hypertension that evaluated the following interventions: (1) self-monitoring (2) educational interventions directed to the patient (3) educational interventions directed to the health professional (4) health professional (nurse or pharmacist) led care (5) organisational interventions that aimed to improve the delivery of care (6) appointment reminder systems. Outcomes assessed were: (1) mean systolic and diastolic blood pressure( 2) control of blood pressure (3) proportion of patients followed up at clinic. DATA COLLECTION AND ANALYSIS: Two authors extracted data independently and in duplicate and assessed each study according to the criteria outlined by the Cochrane Collaboration Handbook. MAIN RESULTS: 56 RCTs met our inclusion criteria. The methodological quality of included studies was variable. An organized system of regular review allied to vigorous antihypertensive drug therapy was shown to reduce blood pressure (weighted mean difference -8.2/-4.2 mmHg, -11.7/-6.5 mmHg, -10.6/-7.6 mmHg for 3 strata of entry blood pressure) and all-cause mortality at five years follow-up (6.4% versus 7.8%, difference 1.4%) in a single large RCT- the Hypertension Detection and Follow-Up study. Other interventions had variable effects. Self-monitoring was associated with moderate net reduction in diastolic blood pressure (weighted mean difference (WMD): -2.0 mmHg, 95%CI: -2.7 to -1.4 mmHg, respectively. Appointment reminders increased the proportion of individuals who attended for follow-up. RCTs of educational interventions directed at patients or health professionals were heterogeneous but appeared unlikely to be associated with large net reductions in blood pressure by themselves. Health professional (nurse or pharmacist) led care may be a promising way of delivering care, with the majority of RCTs being associated with improved blood pressure control, but requires further evaluation. AUTHORS' CONCLUSIONS: Family practices and community-based clinics need to have an organized system of regular follow-up and review of their hypertensive patients. Antihypertensive drug therapy should be implemented by means of a vigorous stepped care approach when patients do not reach target blood pressure levels
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