A simple mathematical predictive tool for estimation of a hydrate inhibitor injection rate

Formiranje hidrata u proizvodnji, postrojenjima za obradu i cjevovodima je problem koji industriju prirodnoga plina stoji milijune dolara. Stoga je shvaćanje početka nastanka hidrata nužno za prevladavanje problema hidrata. Cilj prvog koraka ove studije je razvitak korelacije, jednostavne za korištenje, za predviđanje uvjeta za nastajanje hidrata "slatkih" prirodnih plinova.. Ta jednostavna korelacija predviđa tlak nastajanja hidrata "slatkih" prirodnih plinova za tlak do 400 bara (40 000 kPa) i temperature između 13,15 °C i 24,85 °C (260 K i 298 K), kao i molne mase u rasponu od 16 do 29. U slijedećem koraku razvijene su nove empirijske korelacije radi predviđanja potrebnog masenog postotka mono etilen glikola (MEG) u obogaćenim otopinama i količine protjecanja u jedinici vremena za željeno snižavanje temperature formiranja plinskog hidrata. Ove korelacije su napravljene za prirodni plin relativne gustoće 0.6 kod tlaka od 3, 5, 7 i 9 MPa (30, 50, 70 i 90 bara) koji su primjenjivi za masni prirodni plin temperature od 20, 30, 40 i 50 °C. Kako bi se proširila primjenjivost ovih korelacija na širi spektar mješavina prirodnoga plina relativne gustoće do 0,8, dana su dva poopćena korekcijska faktora. Točnost ove jednostavne metode uspoređena je s rezultatima simulacije dobivenim korištenjem komercijalnoga softwarea pri čemu se je pokazala izuzetna podudarnost. U svim slučajevima postotak pogreške iznosio je približno 2% i 5% za predviđanje pada temperature formiranja hidrata i obroka utiskivanja mono etilen glikola (MEG). Jednadžbe koje su razvijene u ovoj studiji mogu biti od značajne praktičke važnosti za inženjere i znanstvenike za brzu provjeru uvjeta formiranja hidrata prirodnih plinova s ili bez prisustva inhibitora bez potrebe za primjenom bilo kakvih eksperimentalnih mjerenja. Kemijski i procesni inženjeri će ustanoviti da su jednostavne jednadžbe prilagođene korisniku s jasnim izračunima bez složenih izraza.The formation of hydrates in production, processing facilities and pipelines has been a problem to the natural gas industry, that cost several millions of dollars.. Therefore, an understanding of the inception of hydrate formation is necessary to overcoming hydrate problems. The aim of the first step of this study is to develop a simple-to-use correlation for predicting hydrate-forming conditions of sweet natural gases. This simple correlation estimates hydrate formation pressure of sweet natural gases for pressures up to 40 000 kPa and temperatures between 260 K and 298 K as well as molecular weights in the range of 16 to 29. In the next step, novel empirical correlations are developed to predict the required MEG weight percent in the rich solution and the flow-rate for desired depression of the gas hydrate formation temperature. These correlations are generated for a natural gas with relative density of 0.6 at pressures of 3, 5, 7, and 9 MPa, which are applicable to wet gas temperatures of 20, 30, 40, and 50 °C. In order to extend the application of these correlations to wide ranges of natural gas mixtures with specific gravities of up to 0.8, two generalized correction factors are also provided. The accuracy of this simple method is compared with the simulation results obtained by commercial software which showed excellent agreement. In all cases the error percent was approximately 2% and 5% for predicting hydrate formation temperature depression and MEG injection rate, respectively. The fitted equations developed in this study can be of immense practical value for the engineers and scientists to have a quick check on hydrate formation condition of natural gases with or without presence of inhibitor without opting for any experimental measurements. In particular, chemical and process engineers would find the simple equations to be user-friendly with transparent calculations involving no complex expressions

A Multi-Period Synthesis Approach to Designing Flexible Heat- Exchanger Networks

This chapter presents a new synthesis method for designing flexible heat-exchanger networks. The methodology used involves a two-step approach: In the first step, a multi-period network is designed for a large number of critical operating periods using a finite set of operating points which lie within the uncertain parameter range, while considering the impact of potential fluctuations in periodic durations of each of the chosen critical points on the network. In the second step, the flexibility of the resulting multi-period network of the first step is tested using very large, randomly generated set of finite potential operating points together with their periodic durations. The key criteria used in determining the finite set of operating points that would participate in the initial multi-period network synthesis of the first step are the nominal operating points, the extreme operating points in terms of heat-load requirements as well as their length of periods. This implies that the resulting flexible network can feasibly transfer heat irrespective of possible fluctuations in periodic durations for any of the potential process-operating points. The solutions obtained using the new approach compare favourably with those in the literature

Prediction of Formation Water Properties Using a Novel Predictive Tool Approach and Vandermonde Matrix

Proizvodnja mokre sirove nafte je zbog podizanja kontakta nafta-voda na mnogim naftnim poljima sve veći problem i zbog toga proizvodnja slane mokre nafte utiče na kvalitetu sirove nafte. U ovom radu je predstavljena jednostavna metoda za procjenu svojstava slojne vode korištenjem Arrhenius-ove funkcije i Vandermondove matrice za temperature iznad 30 °C i sadržaja soli između 5 i 25% masenog postotka. Ustanovljeno je da se procjene odlično poklapaju s vjerodostojnim podacima iz literature sa srednjim apsolutnim odstupanjem koje varira između 0,08 do 2,7%. Metoda koja je razvijena u ovoj studiji je od velike važnosti za naftne inženjere i inženjere u praksi jer im omogućava brzu provjeru svojstava slojne vode kod različitih uvjeta bez potrebe izbora bilo koje eksperimentalne metode. Kemijski i naftni inženjeri će ustanoviti da je predloženi pristup prilagođen korisniku s transparentnim izračunima koji ne uključuju složene izraze.Production of wet crude due to the raise in oil-water contact in many oil fields has been a growing field problem and consequently production of salty wet crude affects the quality of crudes. In this work a simple method using Arrhenius-type function and Vandermonde matrix is presented for estimation of formation water properties for temperatures above 30 °C and salt contents between 5 and 25% by mass. Estimations are found to be in excellent agreement with the reliable data in the literature with average absolute deviation varying between 0.08 to 2.7%. The method developed in this study is of immense practical value for petroleum engineers and practice engineers for a quick check on the formation water properties at various conditions without opting for any experimental measurements. In particular chemical and petroleum engineers would find the proposed approach to be user-friendly with transparent calculations involving no complex expressions

Prediction of Formation Water Properties Using a Novel Predictive Tool Approach and Vandermonde Matrix

Proizvodnja mokre sirove nafte je zbog podizanja kontakta nafta-voda na mnogim naftnim poljima sve veći problem i zbog toga proizvodnja slane mokre nafte utiče na kvalitetu sirove nafte. U ovom radu je predstavljena jednostavna metoda za procjenu svojstava slojne vode korištenjem Arrhenius-ove funkcije i Vandermondove matrice za temperature iznad 30 °C i sadržaja soli između 5 i 25% masenog postotka. Ustanovljeno je da se procjene odlično poklapaju s vjerodostojnim podacima iz literature sa srednjim apsolutnim odstupanjem koje varira između 0,08 do 2,7%. Metoda koja je razvijena u ovoj studiji je od velike važnosti za naftne inženjere i inženjere u praksi jer im omogućava brzu provjeru svojstava slojne vode kod različitih uvjeta bez potrebe izbora bilo koje eksperimentalne metode. Kemijski i naftni inženjeri će ustanoviti da je predloženi pristup prilagođen korisniku s transparentnim izračunima koji ne uključuju složene izraze.Production of wet crude due to the raise in oil-water contact in many oil fields has been a growing field problem and consequently production of salty wet crude affects the quality of crudes. In this work a simple method using Arrhenius-type function and Vandermonde matrix is presented for estimation of formation water properties for temperatures above 30 °C and salt contents between 5 and 25% by mass. Estimations are found to be in excellent agreement with the reliable data in the literature with average absolute deviation varying between 0.08 to 2.7%. The method developed in this study is of immense practical value for petroleum engineers and practice engineers for a quick check on the formation water properties at various conditions without opting for any experimental measurements. In particular chemical and petroleum engineers would find the proposed approach to be user-friendly with transparent calculations involving no complex expressions

Evaluation of Cracking Performance of Bridge Decks Incorporating Nonmetallic Fibers

The Minnesota Department of Transportation (MnDOT) identified 20 monolithic (onecourse) bridge decks, constructed between 2015 and 2018, for cracking surveys to investigate the effectiveness of nonmetallic fibers in reducing bridge deck cracking. Of the 20 monolithic decks, 13 were constructed with concrete mixtures containing nonmetallic fibers and seven without fibers. Of the bridge decks constructed with nonmetallic fibers, nine are supported by precast-prestressed concrete girders and four are supported by steel girders. Of the decks constructed without fibers, six are supported by precast-prestressed concrete girders and one is supported by steel girders. The first portion of the report (Chapters 1 through 4) presents a description of the crack survey procedures, followed by information about the decks. A comparison of the decks is then made by converting the survey results to equivalent crack densities at 36 months of age. The second portion of the report (Chapters 5 and 6) investigates the effects of paste content, fibers, and construction procedures on the cracking performance of the 20 bridge decks surveyed in this study using comparisons with the results of crack surveys of 74 other bridge deck placements, conducted in Kansas, Virginia, and Indiana. Results show that for the decks surveyed in this study, the majority of cracks that contributed to crack density had lengths greater than 1 ft and there is no apparent correlation between the use of fibers and crack width. Low cracking bridge decks require the use of concrete with a low paste content (27.1% or less), and when the paste content is 27.1% or less, there is no significant difference in the average 36-month crack densities between bridge decks with and without fibers. More generally, good construction practices are needed for low-cracking decks, and with poor construction practices, even decks with low paste content, with or without fibers, can exhibit high crackin

The Necessity of Management Team Formation and Its Effect on Civil Engineering Projects Success

Success of a project is one of the greatest and most important goals and concerns of mangers and all people involved in a project. The purpose of state civil engineering projects success is to decrease cost and time as well as increasing the quality and satisfaction of society and government as the main customers. Many factors influence civil engineering projects success and identifying them highly help the successful implementation of civil engineering projects. As one of the most important factor, it can be referred to project management team. The main purpose of the present study is to find the effective relation between management team formation and civil engineering projects success. To this end, library and field methods have been used. To gather required data, a 15-item questionnaire has been employed and distributed among 30 managers of successful state projects, including employer, consultant and contractor. The obtained data has been analyzed using descriptive method. As the findings revealed, weakness of managerial factors avoids complete success of state civil engineering projects implementation. The study also has concluded that team formation is highly important to organize project; management team enabling is regarded necessary for organizational projects success, and work relation of team members plays an important role in project management success

Improving radar performance with constant envelope multi-level chirp

M-level Continuous Phase Chirp Modulation is considered for data transmission. In this article, we would like to propose a new approach to transmitting information with the help of multi-level wave guide signaling. The main problem with the classic chirp modulation system is that the final phase of the signal is not equal in each period to the initial phase of the next step, and this discontinuity is present in each data transmission period. The main objective of this paper is to improve the efficiency of chirp modulation, which is recommended for continuous phase multi-level scalar modulation, which results has a significant increase in system performance. In this new approach, for sending the M symbols, we use the M level to send the message. With the help of this idea, we simulate the telecommunication system and examine the probability of its bit error in the presence of additive white Gaussian noise and Rician fading

Designing a Comprehensive Evaluation Model for Health System Reform Plan in Iran: An Approach to Extended Balanced Scorecard

Background: Health and striving to maintain and promote it has always been an important priority in governments, communities, and public policies. To implement health objectives through the Fifth Five-Year National Development Plan of Iran, the health system reform plan with three approaches to the financial protection of the public, creating equity in access to health services, and improving the quality of services has been on the government's agenda since 05.05.2014. Investigations revealed that the lack of a comprehensive and scientific model for evaluating this national program is evident. This study aimed to design a comprehensive model of health reform plan evaluation in Iran. What distinguishes this study from previous studies is the simultaneous attention to the challenges of performance evaluation, social responsibility, and examining them in a comprehensive and coherent model.Materials and Methods: The present study considered as descriptive-survey research in terms of strategy. The research method was a combination that conducted from 2018 to 2019. The sample size of the qualitative part of the research consisted of 17 academic and executive health experts selected by purposive non-random sampling. In the quantitative part of the study, 400 health service providers selected by stratified random sampling. In this study, content analysis and Delphi technique, and Expert choice v24, SPSS V22 and AMOSV14 software were used to collect, classify, deduce and exploit data, and questionnaires.Results: The findings of this study resulted in the design of a 900-scorecard model of the comprehensive evaluation of the health system reform plan in Iran based on 5 dimensions (finance, social responsibility, growth and learning, clients and internal processes), 17 components and 70 indicators.Conclusion: The findings of the quantitative section of the study showed that the indicators, dimensions and levels of the comprehensive evaluation model for health system reform plan in Iran (CEHSRP-IR) qualified for evaluation of the effectiveness of this national program at different organizational levels and executing units of health system reform plan in Iran

Strategy mapping and introducing the Health System Reform Plan: An Iranian social responsibility-based approach

Background: The main function of the strategy map is to determine the relationship between cause and effect among the strategic objectives, dimensions, and components of an organization, a large project or plan in which programs can be implemented effectively.  The current study aimed to map strategy and introduce the health system reform plan using an Iranian social responsibility-based approach.   Methods: The current study was a qualitative and applied one using the Balanced Scorecard (BSC) principles and the Comprehensive Evaluation Model for Health System Reform Plan in Iran (CEHSRP-IR) model in 2019. the views of 17 experts were selected in management and health issues based on purposive non-random sampling, using Delphi technique paired comparisons, common techniques in strategy mapping, and SPSS and EXPERT CHOICE software, the strategy map of the health system reform plan was designed in Iran.   Results: After elaborating on the fundamental aspects of this research, setting the strategic goals, dimensions, and components, as well as determining the relative weight of the components and dimensions and then prioritizing them, explained their optimal relationships to achieve strategic goals. Finally, using VISIO software, a strategy for the health system reform plan was designed and presented concerning social responsibilities. The present study resulted in designing a strategy map of the health system reform plan in Iran based on 5 dimensions of financial, social responsibility, learning and growth, clients, internal processes, 17 components, and 25 connections.   Conclusion: The current strategy map can be sufficiently comprehensive to effectively implement nationally at various organizational and implementing units’ levels of the health system reform plan in Iran

Construction Of Low-Cracking High-Performance Bridge Decks Incorporating New Technology

Construction and early-age crack evaluations of four bridge decks in Minnesota placed from 2016 to 2018 that incorporate specifications for Internally-Cured Low-Cracking High-Performance Concrete (IC-LC-HPC) are documented in this study. Two additional decks that serve as Controls followed specifications for high-performance concrete and paired with IC-LC-HPC decks are included. Pre-wetted fine lightweight aggregate was used to provide a targeted internal curing water content of 8% by total weight of binder. The IC-LC-HPC mixtures included 27 to 30% slag cement by total binder weight while the Control mixtures included 25 or 35% Class F fly ash by total weight of binder. For one IC-LC-HPC deck, mixture proportions were modified based on a higher FLWA absorption than originally used to design the mixture. One IC-LC-HPC placement failed due to errors in FLWA moisture corrections and concrete batching that led to rejections of batches, leaving an inadequate supply of material to complete the deck. Crack surveys were completed for the IC-LC-HPC and Control decks placed in 2016 and 2017. Crack densities at these ages were low compared to most Low-Cracking High-Performance Concrete decks in Kansas and Internally-Cured High-Performance Concrete decks in Indiana, with the exception of one IC-LCHPC deck that exhibited extensive cracking within one year after placement, which had an overlay with a high cement paste content and no internal curing. This project serves as a foundation for implementing IC-LC-HPC in upcoming bridge decks in Kansas and Minnesota.Kansas Department of Transportation and Minnesota Department of Transportation “Construction of Low-Cracking High-Performance Bridge Decks Incorporating New Technology” Transportation Pooled Fund Study, Project No. TPF-5(336)