scholarly journals A Novel Optimized Formulation for Cooling Tower Effluent Disinfection: Tarasht Power Plant Case Study

Author(s):  
Ehsan Sohrabi ◽  
Somayeh Sohrabi ◽  
Davood Iranshahi ◽  
Majid Sarmadi ◽  
Mostafa Keshavarz Moraveji

Abstract Since the operating conditions of the cooling tower units provide such a suitable environment for the growth of bacteria and algae, taking measures for the disinfection process is strongly recommended. The cooling tower unit is proceeded by RO and the disinfection strategy is sodium hypochlorite, combined with this new formulation. The sampling result revealed that bacteria counts from the effluent of the cooling tower are 2600 CFU/ml while the microbial load of the water in the pond is 220 CFU/ml. Herein, two type formulations are introduced for cooling tower output stream while the pond water comes along with a NaOCl injection. The dosage of A: Glucose Oxidase, B: ammonium persulfate, and C: Amoxicillin, and D: the order of use are chosen as the four independent variables whose effects and their binary interactions on microbial load and disinfection efficiency were investigated via Box–Behnken design (BBD) combined with response surface methodology (RSM). The ANOVA results show that the most significant variable is amoxicillin in the presence of bleach. Meanwhile, high values for R2 > 0.99 and the model F-value 45.64 in addition to diagnostic tests confirmed the reliability of the model. Several solutions have been introduced as optimum formulations. The pre-scale up and economic considerations have been included.

Author(s):  
Virgile Delhaye ◽  
Madjid Karimirad ◽  
Petter Andreas Berthelsen

In this paper, the original double symmetric cross section beam formulation in RIFLEX used to model the blades is compared against a newly implemented generalised beam formulation, allowing for eccentric mass, shear and elastic centres. The generalised beam formulation is first evaluated against an equivalent ABAQUS beam model (Using the generalised beam formulation implemented in ABAQUS) which consists of DTU 10MW RWT (reference wind turbine) blade in static conditions. A static displacement is applied to the tip, which is close to an operating load. The results appear very similar and ensure that the implementation is correct. The extended beam formulation is afterwards used on the Land-based 10MW turbine from DTU with external controller. This case study aims at evaluating the effect of the newly implemented formulation on realistic, flexible structure. During the study, the blades were discretised using both the old and new formulation, and dynamic simulations were performed. The effect of the beam formulation was evaluated using several wind conditions that are thought to be characteristic of operating conditions. Results show slight difference between two formulations but could be more significant for next generation flexible blades.


Buildings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 78
Author(s):  
Daria Uspenskaia ◽  
Karl Specht ◽  
Hendrik Kondziella ◽  
Thomas Bruckner

Without decarbonizing cities energy and climate objectives cannot be achieved as cities account for approximately two thirds of energy consumption and emissions. This goal of decarbonizing cities has to be facilitated by promoting net-zero/positive energy buildings and districts and replicating them, driving cities towards sustainability goals. Many projects in smart cities demonstrate novel and groundbreaking low-carbon solutions in demonstration and lighthouse projects. However, as the historical, geographic, political, social and economic context of urban areas vary greatly, it is not always easy to repeat the solution in another city or even district. It is therefore important to look for the opportunities to scale up or repeat successful pilots. The purpose of this paper is to explore common trends in technologies and replication strategies for positive energy buildings or districts in smart city projects, based on the practical experience from a case study in Leipzig—one of the lighthouse cities in the project SPARCS. One of the key findings the paper has proven is the necessity of a profound replication modelling to deepen the understanding of upscaling processes. Three models analyzed in this article are able to provide a multidimensional representation of the solution to be replicated.


2005 ◽  
Vol 32 (4) ◽  
pp. 719-725 ◽  
Author(s):  
Joyce Li Zhang ◽  
K Ponnambalam

This paper describes the implementation of a new solution approach — Fletcher-Ponnambalam model (FP) — for risk management in hydropower system under deregulated electricity market. The FP model is an explicit method developed for the first and second moments of the storage state distributions in terms of moments of the inflow distributions. This method provides statistical information on the nature of random behaviour of the system state variables without any discretization and hence suitable for multi-reservoir problems. Also avoiding a scenario-based optimization makes it computationally inexpensive, as there is little growth to the size of the original problem. In this paper, the price uncertainty was introduced into the FP model in addition to the inflow uncertainty. Lake Nipigon reservoir system is chosen as the case study and FP results are compared with the stochastic dual dynamic programming (SDDP). Our studies indicate that the method could achieve optimum operations, considering risk minimization as one of the objectives in optimization.Key words: reservoir operations, explicit method, uncertainty, stochastic programming, risk.


2021 ◽  
Vol 11 (4) ◽  
pp. 1-54
Author(s):  
Mohammad Rishad Faridi ◽  
Saloni Sinha

Learning outcomes Appendix 1: Comic Frames A At the end of the case study discussion, students will able to as follows: Explain various growth strategies as a potential unicorn with the exponential growth mindset rather than linear growth mindset through adaptation of Massive Transformative Purpose (MTP) and Moonshot Thinking (MT). Demonstrate innovative and creative plans and ideas, with the ability to scale up in the circular economy. Review and summarize the power of Collaborative Innovation (CI). Compare and contrast different ways in dealing with Hedgehog and Fox style of leadership into the business. Appendix 2: Comic Frames B At the end of the case study discussion, students will able to as follows: Act with a growth strategy as a potential unicorn with the exponential growth mindset rather than linear growth mindset through adaptation of MTP and MT. Simulate innovative and creative plans and ideas, with the ability to scale up in the circular economy. Assess and leverage the power of CI. Decide and differentiate in dealing with Hedgehog and Fox style of leadership into the business. Case overview/synopsis Ankit Tripathi, was a compassionate 22-year-old, the typical lad from New Delhi, India, who seemed driven to change the world. His elder brother Atul Tripathi, a young, creative 25-year-old, was sat there next to him, beaming with pride and gratitude. Both brothers, being mechanical engineering graduates, had experienced the advancement of technology at the cost of Mother Earth. It pained them no end. It was the reason that Atul had refused to serve as an engineer in a government institution after graduating. The parents were shocked when Ankit followed suit. The brothers were poles apart in their personality and temperament, and it was rare to see them agree on anything in this way. Yet, they agreed to disagree with their parents and ventured into becoming entrepreneurs with a purpose and passion to salvage the environment. They had a vision, but without a proper roadmap, it would certainly be a tough game. Nevertheless, they boldly embarked upon their journey and established their start-up “Uneako” in 2019. “Uneako” was a calculated risk, taking into account family resistance (parents’ attitude/perception), personal conflicts (psychological), financial limitations (resources), shallow expertise (professionalism), social concern acceptability and low awareness (environment), government regulations (legalities/approvals), conflicts between brothers (personality issues), etc. Being from a nonbusiness family, the brothers had defied the wave of obstacles and challenges in daring to start their own business, putting at stake the hard-earned money of their father, Satendra Tripathi. Amidst so much social mockery, would Atul and Ankit succumb and become a laughing stock or would they find something that they could live and die for? Complexity Academic Level Appendix 1: Comic Frames A: This case has been particularly focused on undergraduate level students pursuing business or commerce programs. Especially those studying core courses, for example, entrepreneurial and strategic management. Appendix 2: Comic Frames B: This case has been particularly focused postgraduate-early stage or higher level students pursuing business or commerce programs. Particularly those specializing in entrepreneurial and strategic management courses. Also, can be taught in the entrepreneurial or start-up workshops. Supplementary materials www.pewresearch.org/topics/generation-z/ Paulynice. J.P., (2019) “From Idea to Reality: An Entrepreneur’s Guide to Meaningful Business Growth” Paulynice Consulting Group. Hardy.D., (2015) “The Entrepreneur Roller Coaster: It’s Your Turn to Join The Ride” Success Publishers. Wadhwa.V., Amla.I., Salkever.A., (2020) “From Incremental to Exponential” Berrett-Koehler Publishers. Sustainable Entrepreneurship: Business Success through Sustainability edited by Christina Weidinger, Franz Fischler, René Schmidpeter, Springer 2014. Teaching notes are available for educators only. Subject code CSS 3: Entrepreneurship.


2021 ◽  
Author(s):  
Mohamed Ibrahim Mohamed ◽  
Ahmed Mahmoud El-Menoufi ◽  
Eman Abed Ezz El-Regal ◽  
Ahmed Mohamed Ali ◽  
Khaled Mohamed Mansour ◽  
...  

Abstract Field development planning of gas condensate fields using numerical simulation has many aspects to consider that may lead to a significant impact on production optimization. An important aspect is to account for the effects of network constraints and process plant operating conditions through an integrated asset model. This model should honor proper representation of the fluid within the reservoir, through the wells and up to the network and facility. Obaiyed is one of the biggest onshore gas field in Egypt, it is a highly heterogeneous gas condensate field located in the western desert of Egypt with more than 100 wells. Three initial condensate gas ratios are existing based on early PVT samples and production testing. The initial CGRs as follows;160, 115 and 42 STB/MMSCF. With continuous pressure depletion, the produced hydrocarbon composition stream changes, causing a deviation between the design parameters and the operating parameters of the equipment within the process plant, resulting in a decrease in the recovery of liquid condensate. Therefore, the facility engineers demand a dynamic update of a detailed composition stream to optimize the system and achieve greater economic value. The best way to obtain this compositional stream is by using a fully compositional integrated asset model. Utilizing a fully compositional model in Obaiyed is challenging, computationally expensive, and impractical, especially during the history match of the reservoir numerical model. In this paper, a case study for Obaiyed field is presented in which we used an alternative integrated asset modeling approach comprising a modified black-oil (MBO) that results in significant timesaving in the full-field reservoir simulation model. We then used a proper de-lumping scheme to convert the modified black oil tables into as many components as required by the surface network and process plant facility. The results of proposed approach are compared with a fully compositional approach for validity check. The results clearly identified the system bottlenecks. The model can be used to propose the best tie-in location of future wells in addition to providing first-pass flow assurance indications throughout the field's life and under different network configurations. The model enabled the facility engineers to keep the conditions of the surface facility within the optimized operating envelope throughout the field's lifetime.


2001 ◽  
Author(s):  
E. D. Rogdakis ◽  
V. D. Papaefthimiou

Abstract It is a general trend today, the old centrifugal machines to be replaced by new absorption machines. The mass flow rate of the cooling water in the centrifugal machines is normally 30% less than that in the two-stage absorption chiller for the same refrigerating capacity. Some absorption chillers manufacturers have updated and improved the double-effect technology increasing the cooling water temperature difference from the typical value of 5.5°C to 7.4°C and reducing the cooling water flow rate by about 30%. Using such a modern double effect absorption unit to replace a centrifugal chiller the same cooling water circuit can be used and the total cost of the retrofit is minimized. In this case a new flow pattern of the cooling tower is developed, and in this paper the design of a new tower fill is predicted taking into account the new factors characterizing the operating conditions and the required performance of the tower. As an example, the operational curves of a modified cooling tower (1500 KW cooling power) used by a 240 RT double-effect absorption chiller are presented.


2016 ◽  
Vol 16 (6) ◽  
pp. 1639-1647 ◽  
Author(s):  
Ying Ouyang ◽  
Gary Feng ◽  
John J. Read ◽  
Theodor D. Leininger ◽  
Johnie N. Jenkins

Although more on-farm storage ponds have been constructed in recent years to mitigate groundwater resources depletion in Mississippi, little effort has been devoted to estimating the ratio of on-farm water storage pond size to irrigated crop land based on pond metrics and its hydrogeological conditions. In this study, two simulation scenarios were chosen to determine such a ratio as well as to investigate pond hydrological processes using a Structural Thinking, Experimental Learning Laboratory with Animation (STELLA) model, one scenario with and the other without using pond water for irrigation for a typical pond that represented the average conditions in East Mississippi. Simulation results showed that pond water level changed moderately for conditions without using its water for irrigation, whereas pond water level changed dramatically for conditions with using its water for irrigation. A reasonable ratio of pond size to irrigated soybeans land was 1:18 if the irrigation rate was 2.54 cm/d (or 1 inch/d) and the low limit of the pond water level was drawn to near zero (0.08 m). For the ratio of 1:18, our simulations further revealed that a 1-ha soybeans land could save about 542 m3 groundwater each year. This study suggests that the STELLA model is a useful tool for estimating the ratio of pond size to irrigated crop land.


2018 ◽  
Vol 16 (06) ◽  
pp. 1850052
Author(s):  
Y. H. Lee ◽  
M. Khalil-Hani ◽  
M. N. Marsono

While physical realization of practical large-scale quantum computers is still ongoing, theoretical research of quantum computing applications is facilitated on classical computing platforms through simulation and emulation methods. Nevertheless, the exponential increase in resource requirement with the increase in the number of qubits is an inherent issue in classical modeling of quantum systems. In the effort to alleviate the critical scalability issue in existing FPGA emulation works, a novel FPGA-based quantum circuit emulation framework based on Heisenberg representation is proposed in this paper. Unlike previous works that are restricted to the emulations of quantum circuits of small qubit sizes, the proposed FPGA emulation framework can scale-up to 120-qubit on Altera Stratix IV FPGA for the stabilizer circuit case study while providing notable speed-up over the equivalent simulation model.


2019 ◽  
Vol 18 ◽  
pp. 44
Author(s):  
Anita Cassidy

<p>In 2015 the City of Burlington developed a new 2015-2040 Strategic Plan: <em>Grow Bold, </em>which tasked Burlington Economic Development Corporation (BEDC) with supporting the start up and scale up of companies and making Burlington a start up destination. This article will outline the process that BEDC went through to better understand the local innovation ecosystem and the role that BEDC could play in supporting it. This process resulted in BEDC going from no role in supporting companies to start and grow to launching, TechPlace, Burlington’s new innovation Centre in 2017, which supported over 4,000 visitors in their entrepreneurial journey in year one of operations. </p><p><strong>Keywords: </strong>Innovation, Entrepreneurship, Startups, Job Creation, Startup Support, Innovation Centre</p>


2021 ◽  
pp. 58-58
Author(s):  
Farshad Panahizadeh ◽  
Mahdi Hamzehei ◽  
Mahmood Farzaneh-Gord ◽  
Villa Ochoa

Absorption chillers are one of the most used equipment in industrial, commercial, and domestic applications. For the places where high cooling is required, they are utilized in a network to perform the cooling demand. The main objective of the current study was to find the optimum operating conditions of a network of steam absorption chillers according to energy and economic viewpoints. Firstly, energy and economic analysis and modeling of the absorption chiller network were carried out to have a deep understanding of the network and investigate the effects of operating conditions. Finally, the particle swarm optimization search algorithm was employed to find an optimum levelized total costs of the plant. The absorption chiller network plant of the Marun Petrochemical Complex in Iran was selected as a case study. To verify the simulation results, the outputs of energy modeling were compared with the measured values. The comparison with experimental results indicated that the developed model could predict the working condition of the absorption chiller network with high accuracy. The economic analysis results revealed that the levelized total costs of the plant is 1730 $/kW and the payback period is three years. The optimization findings indicated that working at optimal conditions reduces the levelized total costs of the plant by 8.5%, compared to the design condition.


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