scholarly journals PREDICTING THE IMPACT OF A FCC TURBO EXPANDER ON PETROLEUM REFINERIES

2010 ◽  
Vol 9 (1-2) ◽  
pp. 40
Author(s):  
N. E. G. Fermoselli
Keyword(s):  
Flue Gas ◽  
Operational Conditions ◽  
Oil Refineries ◽  
Start Up ◽  
Special Software ◽  
Third Stage ◽  
Turbo Expander ◽  
High Investment ◽  
Petroleum Refineries ◽  
The Impact

Implementing a turbo expander connected to a fluid catalytic cracking (FCC) unit in order to produce power from flue gas has already become a common practice in oil refineries worldwide. Despite of recovering energy which used to be wasted in an orifice chamber, the implementation of expander and its skids still requires high investment, which often begins with a third-stage cyclones installation to enhance flue gas cleanness. Moreover, machine and also pipes need to be made with special materials in order to resist high temperatures and erosion. Hence, there are some items to be checked before start up a turbo expander to ensure the return on investment will reach expectations, keeping in mind that its ability to extract energy from flue gas changes widely depending on FCC operational conditions. Then, the aim of this paper is to provide the analysis of one stage turbo expander which is fed with flue gas from partial combustion FCC unit and installed with isolation valves, highlighting some points which deserve special attention before start up this type of machine. It brings together some approaches to provide valuable information about a turbo expander, particularly when it is not running yet, including the results to a hypothetical case and the sequence of calculus that can be done without using any special software applied for: • To estimate real energy generation through the turbo expander as a function of FCC feed; • To check the leaks effect; • To predict the impact of turbo expander on carbon monoxide boiler, due to a fall in temperature of the expanded flue gas; • To calculate the appropriate amount of extra supplementary gas required to be burned in the flue gas boiler in order to keep the production of steam stable; • To analyze the moisture of the flue gas so that it may predicts condensation when hot gas comes into contact with the cold duct, after opening isolation valves; • And finally, how turbo expanders fit in cleaning development mechanism to get certified carbon credits.

Clients' Expectations on Audit Judgments: A Note

2004 ◽  
Vol 16 (1) ◽  
pp. 63-74 ◽  
Author(s):  
Venkataraman M. Iyer ◽  
Dasaratha V. Rama
Keyword(s):  
Audit Quality ◽  
Financial Statements ◽  
Early Years ◽  
Relative Power ◽  
Client Perceptions ◽  
Audit Firm ◽  
Auditor Tenure ◽  
Start Up ◽  
Nonaudit Services ◽  
The Impact

Audited financial statements can be viewed as the product of negotiations between a company's management and its auditor. Relative power of these two parties is a major factor that determines the outcome of the negotiation. This study examines the impact of auditor tenure, importance of a client to an audit partner, nonaudit purchases, and prior audit firm experience of client personnel on client perceptions about their ability to persuade the auditor in the context of an accounting disagreement. We obtained responses to a survey from 124 CPAs in industry who are employed as CEOs, CFOs, controllers, or treasurers. Our results indicate that respondents from companies with short auditor tenures were somewhat more likely to indicate that they could persuade the auditor to accept their (client's) position in case of a disagreement. This finding is consistent with the argument that auditors are susceptible to influence in the early years as they are still in the process of recouping start-up costs, but is not consistent with concerns expressed by legislators and others that long auditor tenures will adversely affect audit quality. Respondents who believed their business was more important for the audit partner were also more likely to believe that they could persuade the auditor. However, the purchase of nonaudit services and prior audit experience were not related to client's perceptions about their ability to persuade the auditor.

scholarly journals Association of temporary Environmental Protection Agency regulation suspension with industrial economic viability and local air quality in California, United States

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Emily Chang ◽  
Kenneth Zhang ◽  
Margaret Paczkowski ◽  
Sara Kohler ◽  
Marco Ribeiro
Keyword(s):  
United States ◽  
Air Quality ◽  
Environmental Protection ◽  
Environmental Protection Agency ◽  
Manufacturing Industry ◽  
Economic Viability ◽  
Treatment Control ◽  
Oil Refineries ◽  
Pollution Levels ◽  
The Impact

Abstract Background This study seeks to answer two questions about the impacts of the 2020 Environmental Protection Agency’s enforcement regulation rollbacks: is this suspension bolstering the economic viability of industries as oil and manufacturing executives claim they will and are these regulations upholding the agency’s mission of protecting the environment? Results To answer the former question, we utilized 6 months of state employment level data from California, United States, as a method of gauging the economic health of agency-regulated industries. We implemented a machine learning model to predict weekly employment data and a t-test to indicate any significant changes in employment. We found that, following California's state-issued stay-at-home order and the agency’s regulation suspension, oil and certain manufacturing industries had statistically significant lower employment values. To answer the latter question, we used 10 years of PM2.5 levels in California, United States, as a metric for local air quality and treatment–control county pairs to isolate the impact of regulation rollbacks from the impacts of the state lockdown. Using the agency’s data, we performed a t-test to determine whether treatment–control county pairs experienced a significant change in PM2.5 levels. Even with the statewide lockdown—a measure we hypothesized would correlate with decreased mobility and pollution levels—in place, counties with oil refineries experienced the same air pollution levels when compared to historical data averaged from the years 2009 to 2019. Conclusions In contrast to the expectation that the suspension would improve the financial health of the oil and manufacturing industry, we can conclude that these industries are not witnessing economic growth with the suspension and state shutdown in place. Additionally, counties with oil refineries could be taking advantage of these rollbacks to continue emitting the same amount of PM2.5, in spite of state lockdowns. For these reasons, we ask international policymakers to reconsider the suspension of enforcement regulations as these actions do not fulfill their initial expectations. We recommend the creation and maintenance of pollution control and prevention programs that develop emission baselines, mandate the construction of pollution databases, and update records of pollution emissions.

scholarly journals Multimodal Transport in the Context of Sustainable Development of a City

2021 ◽  
Vol 13 (4) ◽  
pp. 2239
Author(s):  
Marzena Kramarz ◽  
Edyta Przybylska
Keyword(s):  
Sustainable Development ◽  
Freight Transport ◽  
Key Factors ◽  
The Sustainable Development ◽  
Individual Character ◽  
Third Stage ◽  
Multimodal Transport ◽  
Research Questions ◽  
The Individual ◽  
The Impact

Multimodal freight transport in cities is a complex, valid, and vitally important problem. It is more seldom underlined in scientific studies and included in cities’ strategies that devote more attention to passenger transport than freight transport. The increased utilization of multimodal transport matches current transport policy and at the same time, it is one of the most important challenges put before cities striving to achieve sustainable development. In this case, the paper embarks upon the problem of relations between multimodal transport development and the sustainable development of the cities. The objective of the paper is an analysis of the impact of the selected city of the Upper Silesian metropolis on the development of multimodal freight transport and an assessment of the impact of the development of multimodal transport on the sustainable development of the cities of the Upper Silesian metropolis. The authors developed three research questions in order to implement the adopted objective. The process of looking for the answer included four stages. Within the first and second stages, the literature studies and experts’ research allowed for identifying key factors of the multimodal transport development that a city may have an impact on. In the third stage, the research was two-fold and was based on a questionnaire and scenario analysis. Due to the individual character of each of the cities, scenarios were developed for Katowice, being the main economic center of Upper Silesian and Zagłębie Metropolis. As a result of the research, factors have been identified that must be included in a strategy of a city that strives for sustainable development. The last stage of the research focused on the initial concept of the multimodal transport development impact assessment on sustainable development of the cities. Conclusions developed at individual stages allowed for answering the research questions.

scholarly journals The influence of cronyism on entrepreneurial resource acquisition

2021 ◽  
Author(s):  
Junfan Yu ◽  
Saskia De Klerk ◽  
Michael Hess
Keyword(s):  
Community Involvement ◽  
Private Property ◽  
Resource Acquisition ◽  
Property Development ◽  
Network Utilization ◽  
Start Up ◽  
Entrepreneurial Strategies ◽  
Staged Model ◽  
The Impact

AbstractThis research focuses on how entrepreneurs utilize cronyism to acquire resources. A case study method allowed us to explore three firms in the private property development industry in China. These firms uniquely cultivated cronyism and achieved distinctly different outcomes. Our findings highlight Chinese entrepreneurs in start-up ventures and later-stage enterprises employ cronyism. The underlying rationale for using cronyism have common and heterogeneous motivations. The similarity and distinguishing rationale also apply to the impact of cronyism. We also find two contingency working mechanisms for cronyism: entrepreneurial characteristics and a staged model for cronyism. With the firm’s growth, cronyism remains important, but firms with more community involvement outperform others. This research contributes to the theory on strategic network utilization for resource acquisition during entrepreneurial development stages. We investigate how entrepreneurial strategies can assist in adapting to the “rules of the game” while utilizing resources within the set contextual constraints.

How do social skills enable nascent entrepreneurs to enact perseverance strategies in the face of challenges? A comparative case study of success and failure

2014 ◽  
Vol 20 (6) ◽  
pp. 517-541 ◽  
Author(s):  
Wadid Lamine ◽  
Sarfraz Mian ◽  
Alain Fayolle
Keyword(s):  
Social Skills ◽  
New Technology ◽  
New Ventures ◽  
Nascent Entrepreneurs ◽  
Entrepreneurial Process ◽  
Ongoing Research ◽  
Content Type ◽  
Start Up ◽  
The Impact

Purpose – This paper seeks to advance ongoing research in entrepreneurial perseverance. While the concept of perseverance is not new, few researchers paid attention to behavioural persistence in the entrepreneurial context. The purpose of this paper is to explore the emergence of new technology based firms (NTBF) by focusing on the role of nascent entrepreneurs’ social skills in the meeting the changes of entrepreneurial perseverance. Design/methodology/approach – In this paper the authors study the start-up phase of entrepreneurial process. The authors opted for a longitudinal case study approach in order to enhance the knowledge on entrepreneurs’ social skills and perseverance. For triangulation purpose the data were gathered using four different information sources. The use of Nvivo8 as the data analysis tool helped to impose a discipline and structure which facilitated the extraction of core insights. Findings – This paper contributes to the understanding of the entrepreneurial perseverance in the context of new venture creation. Particularly, reading the entrepreneurial process through the lens of the perseverance strategies model (Van Gelderen, 2012) provided a way to identify and then to assess the impact of the social skills on the overall entrepreneurial perseverance and their combined impact on the performance of NTBF creation process. In doing so, the authors identify the impact of entrepreneurs’ social skills to deal with a series of entrepreneurial problems such as scarcity of resources, uncertainty and ambiguity and consequently their impact on the likelihood of survival for new ventures. The issues that arose mostly reflected the inherent complexity of technology transfer processes, the university and entrepreneurs’ diverging cultures, and the very characteristics of the start-up phase of NTBFs. The findings reveal how social skills impact the entrepreneurial paths and probable outcomes. Research limitations/implications – This paper contributes to the understanding of the entrepreneurial perseverance in the context of NTBF creation. The findings reveal how social skills and perseverance impact the entrepreneurial paths and probable outcomes. Practical implications – The paper has implications for entrepreneurial support mechanisms such as technology business incubators in helping them to improve the efficacy and efficiency of their assistance to entrepreneurs through the development of their skill-sets and perseverance and providing enabling networking. In addition, the research has implications for entrepreneurship education and training. Indeed, there is an urgent need to design and implement courses and programs aiming at developing soft skills in entrepreneurship. Originality/value – In exploring networking and issues of perseverance for nascent entrepreneurs operating in new technology-based sectors, which the authors consider as an under searched area in entrepreneurial literature.

scholarly journals Biofilm carrier migration model describes reactor performance

2017 ◽  
Vol 75 (12) ◽  
pp. 2818-2828 ◽  
Author(s):  
Joshua P. Boltz ◽  
Bruce R. Johnson ◽  
Imre Takács ◽  
Glen T. Daigger ◽  
Eberhard Morgenroth ◽  
...  
Keyword(s):  
Plug Flow ◽  
Biofilm Reactor ◽  
Bulk Liquid ◽  
Reactor Performance ◽  
Reactor Model ◽  
Operational Conditions ◽  
Limit Model ◽  
Biofilm Model ◽  
Reactor Models ◽  
The Impact

The accuracy of a biofilm reactor model depends on the extent to which physical system conditions (particularly bulk-liquid hydrodynamics and their influence on biofilm dynamics) deviate from the ideal conditions upon which the model is based. It follows that an improved capacity to model a biofilm reactor does not necessarily rely on an improved biofilm model, but does rely on an improved mathematical description of the biofilm reactor and its components. Existing biofilm reactor models typically include a one-dimensional biofilm model, a process (biokinetic and stoichiometric) model, and a continuous flow stirred tank reactor (CFSTR) mass balance that [when organizing CFSTRs in series] creates a pseudo two-dimensional (2-D) model of bulk-liquid hydrodynamics approaching plug flow. In such a biofilm reactor model, the user-defined biofilm area is specified for each CFSTR; thereby, Xcarrier does not exit the boundaries of the CFSTR to which they are assigned or exchange boundaries with other CFSTRs in the series. The error introduced by this pseudo 2-D biofilm reactor modeling approach may adversely affect model results and limit model-user capacity to accurately calibrate a model. This paper presents a new sub-model that describes the migration of Xcarrier and associated biofilms, and evaluates the impact that Xcarrier migration and axial dispersion has on simulated system performance. Relevance of the new biofilm reactor model to engineering situations is discussed by applying it to known biofilm reactor types and operational conditions.

Operational conditions for start-up and nitrate-feeding in an anoxic biotrickling filtration process at pilot scale

2016 ◽  
Vol 285 ◽  
pp. 83-91 ◽  
Author(s):  
Fernando Almenglo ◽  
Martín Ramírez ◽  
José Manuel Gómez ◽  
Domingo Cantero
Keyword(s):  
Pilot Scale ◽  
Filtration Process ◽  
Operational Conditions ◽  
Start Up

scholarly journals Environmental Risk Mitigation by Biodiesel Blending from Eichhornia crassipes: Performance and Emission Assessment

2021 ◽  
Vol 13 (15) ◽  
pp. 8274
Author(s):  
Hasanain A. Abdul Wahhab ◽  
Hussain H. Al-Kayiem
Keyword(s):  
Eichhornia Crassipes ◽  
Risk Mitigation ◽  
Calorific Value ◽  
Slight Reduction ◽  
Ic Engine ◽  
Operational Conditions ◽  
Performance And Emission ◽  
Oil Refineries ◽  
Viable Solution ◽  
Good Potential

The aggressive growth of Eichhornia crassipes (Water Hyacinth) plants causes severe damage to the irrigation, environment, and waterway systems in Iraq. This study aims to produce, characterize, and test biofuel extracted from the Eichhornia crassipes plant in Iraq. The extracted biodiesel was mixed at 10%, 20%, and 40% with neat diesel to produce three biodiesel samples. The methodology consists of the physiochemical properties of the samples that were characterized. The performance of the IC engine fueled by neat and biodiesel samples was measured under various operational conditions. The exhaust gases were analyzed to estimate the compounds to assess the environmental impact. The results showed that the density and viscosity of mixtures increase and the calorific value decrease with biodiesel. The engine test showed that the diesel + 10BE, diesel + 20BE, and diesel + 40BE enhanced brake thermal efficiency using 2.6%, 4.2%, and 6.3%, respectively, compared to neat diesel. Exhaust tests show a slight reduction, of 0.85–3.69% and 2.48–6.93%, in CO and HC emission, respectively. NOx is higher by 1.87–7.83% compared with neat diesel. The results revealed that biodiesel blended from Eichhornia crassipes is a viable solution to mitigate the drastic impact on the environment and economy in Iraq. The blended biodiesel has good potential to be mixed with the locally produced diesel from oil refineries.

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