Booster Station Research Articles

An Artificial Neural Network Model for Prediction of the Operational Parameters of Centrifugal Compressors: An Alternative Comparison Method for Regression

Nowadays, centrifugal compressors are commonly used in the oil and gas industry, particularly in the energy transmission facilities just like a gas pipeline stations. Therefore, these machines with different operational circumstances and thermodynamic characteristics are to be exploited according to the operational necessities. Generally, the most important operational parameters of a gas pipeline booster station includes the compressor's input and output pressures, input and output temperatures and also the flow rate passing from the compressors. Different values of those parameters related to every point of operational conditions will exactly affect on the compressor poly-tropic efficiency and their driver fuel consumption. Although, calculating of the poly tropic efficiency and fuel consumption using the existing thermodynamic relations, would need to apply rather awkward equations for each operating point. In this research, a feed forward perceptron artificial neural network is presented to predict the output operational conditions. The network would be trained at least in two scenarios applying by practical data in the neuro solution software version.5 using the Levenberg-Marquadt algorithm and the optimum model is experimentally selected according to R2, MSE and NMSE.

Numerical Study on Initial Laying Process of Submarine Cables for Wave Energy Booster Station in Real Sea States

Hu, J.; Li, Z., and Zhang, Y., 2020. Numerical study on initial laying process of submarine cables for wave energy booster station in real sea states. In: Zheng, C.W.; Wang, Q.; Zhan, C., and Yang, S.B. (eds.), Air-Sea Interaction and Coastal Environments of the Maritime and Polar Silk Roads. Journal of Coastal Research, Special Issue No. 99, pp. 60-66. Coconut Creek (Florida), ISSN 0749-0208.Based on real sea conditions of the national wave energy demonstration site in Wanshan sea area of Zhuhai City, China, some numerical experiments are carried out to simulate the submarine cables initial laying process of the Wave Energy Booster Station in this demonstration site. The numerical model is established with the Orcaflex software employed. The motion response of laying ship and the hydrodynamic characteristics of submarine cables are simulated here under three sea conditions, i.e. usual waves, waves with current combined and possible extreme waves. Research results show that the tension and curvature of the cable are large under the condition for wave direction perpendicular to the ship axial direction, which is a relatively bad sea condition. The current also has some influences on the submarine cable laying, and the maximum effective tension of cable produced by the combined wave-current action is 1.35 times that of cable with the wave action alone. When extreme waves appear, pitch, heave and heave acceleration of the laying ship and tension of the cable ends increases obviously. And the variation of effective tension at both cable ends can reach 1.67 times that of cable ends under usual random waves. The numerical model and research results in this paper can provide some guidance for the research and construction of the cable laying of booster stations for marine renewable energy power plants in real sea conditions.

Optimization of wind farm collection line structure under symmetrical grid fault

A power-transmission collection line is connected to each wind turbine of a wind farm and then connected to the incoming switchgear at the low-voltage side of the booster station at a certain distance. Therefore, the grouping of the wind turbines in the wind farm determines the layout of the lines and affects the line impedance. The line structure and composition of the wind farm are analyzed, and the relationship between the impedance of the collection line and reactive power generated by the wind turbine at low-voltage ride through is derived. We conclude that the smaller the equivalent impedance of the wind farm collection line structure is, the greater the reactive power at the wind farm collection line point is. In addition, the economic aspect of the collection line needs to be considered in the design. The economic aspect and impedance values have contrasting characteristics. Therefore, according to the condition of minimum impedance and optimized economic aspect, an optimization model of a wind-farm collector-circuit structure is proposed. The optimal structure of the wind farm collector circuit is calculated using the Monte Carlo method, and the theoretical analysis is verified by simulation.

Receding Horizon Optimization of Wind Farm Active Power Distribution with Power Tracking Error and Transmission Loss

In this paper, a receding-horizon optimization strategy is introduced to optimize the wind farm active power distribution with power tracking error and transmission loss. Based on the wind farm transmission connections, a wind farm can be divided into clusters, in which the wind turbine generator systems connected to one booster station can be taken as one cluster, and different clusters connected from booster stations to the farm-level main transformer output the electric power to the grid. Thus, in the proposed strategy, the power tracking characteristic of the wind turbine generator system is modeled as a first-order system to quantify the power tracking error during the power tracking dynamic process, where the power transmission losses from wind turbine generator systems to booster stations are also modeled and considered in the optimization. The proposed strategy is applied to distribute the active power set-point within a cluster while the clusters’ set-point still follows the conventional strategy of the wind farm. Simulation results show significant improvement for both optimization targets of the proposed strategy.

A mixed integer nonlinear programming model for optimizing a gas pipeline transmission linear network

The technical equipment developed and used in both installation and operation processes in refineries, oil and gas pipelines, and gas booster stations has always been expensive. Hence, managers at different organizational levels are keen to find methods to control and reduce these costs. Generally speaking, the operators in a gas booster station choose the operating devices without considering the related costs. This research presents a mixed integer nonlinear programming model designed to minimize the operational costs of gas booster stations in a main pipeline distribution network. The goal is to optimize the choice of operating devices in these stations to minimize costs while still meeting customer demands. Turbo compressors are chosen as the operating devices and the operational costs are fuel, maintenance, start-up, and penalty costs. However, the significance indexes of these costs are valued differently by the three expert managers: the executive officer, operating head, and the overhaul repairing director. Consequently, the analytical hierarchy process (AHP) method is used to calculate the overall weights of costs, and a gas transmission company in the north of Iran is considered as a case study. The model can minimize the total cost, when compared to the selections of ten experienced operators; however, the absolute weights of choosing measures and the essence of the objective function under study mean that an operator choice exists that would represent the optimum selection of turbo compressors.

Optimal Booster Station Design and Operation under Uncertain Load

Given industrial applications, the costs for the operation and maintenance of a pump system typically far exceed its purchase price. For finding an optimal pump configuration which minimizes not only investment, but life-cycle costs, methods like Technical Operations Research which is based on Mixed-Integer Programming can be applied. However, during the planning phase, the designer is often faced with uncertain input data, e.g. future load demands can only be estimated. In this work, we deal with this uncertainty by developing a chance-constrained two-stage (CCTS) stochastic program. The design and operation of a booster station working under uncertain load demand are optimized to minimize total cost including purchase price, operation cost incurred by energy consumption and penalty cost resulting from water shortage. We find optimized system layouts using a sample average approximation (SAA) algorithm, and analyze the results for different risk levels of water shortage. By adjusting the risk level, the costs and performance range of the system can be balanced, and thus the system's resilience can be engineered.

Case Studies in Energy Management: Experience From Germany

The estimated potential for long‐term energy‐efficiency improvement of water/wastewater utilities (WWUs) ranges from 10 to 30%. Energy efficiency measures generally have short payback periods and are more economical than adding renewable energy generation. This article presents experience gained from working with German WWUs on energy efficiency since 2013, focusing on six case studies: (1) making full use of available energy use data, (2) reducing costs by avoiding demand spikes and optimizing electricity contracts, (3) improving the efficiency of over‐dimensioned booster station pumps, (4) reducing energy use for space heating at a water treatment plant, (5) replacing pressure‐reducing valves with turbines to make use of excess hydraulic capacity, and (6) avoiding energy waste of wastewater treatment plant blowers by keeping oxygen sensors properly calibrated. The main partner WWU achieved a 13% improvement in energy efficiency after less than two years of focused energy management, with an average payback period per measure of 1.2 years.

Efficient reduction of optimal disinfectant booster station placement formulations for security of large-scale water distribution networks

ABSTRACTIn response to a contamination incident in water distribution networks, disinfectant booster stations can be used to neutralize the contaminant and protect the public. In this paper, two mixed-integer linear programming formulations are proposed for optimal placement of disinfectant booster stations. The first formulation minimizes the contaminant mass consumed by the public, while the second formulation minimizes the number of people who ingest the contaminant above a mass threshold. The proposed formulations consider uncertainty in both the location and time of the contamination incident, resulting in an intractably large stochastic programming problem. This manuscript proposes a series of reductions that decrease the size of the problem by up to five orders of magnitude. The results show that the use of a small number of disinfectant booster stations can be very effective as a response strategy.

An Intelligent Approach to Predict Vibration Rate in a Real Gas Turbine

Bearings vibration in gas turbines is considered as an injurious event, which results in incidents such as emergency shutdown or damages in turbine blades and imposes expensive costs to the system. Thus, measuring and analyzing of vibration rate in gas turbines is very important and knowing about its operational conditions and prediction of this phenomenon can help a lot in reducing vibration, avoiding damage to the blades and eventually financial savings. In this paper, we are modelling the vibration rate of a real double shaft 25 MW gas turbine, located in Iran, by making use of a hybrid intelligent model based on multi-layer perceptron neural network and cuckoo optimization algorithm; so, the model in this paper is abbreviated as MLP-COA. It should be noted that this work is an absolutely novel work and the idea is implemented in a real turbine for first time. We have used a real dataset with 161 samples which are collected during a year from a gas turbine in a gas pressure booster station. Furthermore, to obtain the effect of each input parameter on the vibration rate, we have applied sensitivity analysis using the cosine amplitude technique. Evaluation of predicted vibration rates was performed and prove satisfactory efficiency of this model than other predictive models such as radial basis function and multi-layer perceptron. The model can also be used for prediction of online vibration rate without any constraint in selection of data points in training phase.

Assessment of Electric-Field ExposureUsing Reliability Analysis

Excessive exposure to high levels of electromagnetic fields can induce adverse health effects. Numerical calculation is often used in the exposure assessments. However, in the traditional methods, the relative variables are all assumed to have fixed values without considering the effect of staff activity. To improve the deficiencies caused by this assumption, a new method for the exposure assessments based on the reliability theory was proposed in this investigation. As an example, the electric-field exposure in the booster station of a power plant with several paths was studied by the new method. The exposure reliability index and the failure probability of each path were first determined. Then, based on the determined reliability indices, the influence of the bus framework on the exposure was discussed by the sensitivity study, and a series system was set up to evaluate the electromagnetic exposure of the entire booster station. The proposed approach could be employed to assess the electric field in the substations by taking into account the staff activity, in order to improve the management of the occupational exposure in the power transmission and distribution projects.

Vibration cause analysis and elimination of reciprocating compressor inlet pipelines

Due to the occurrence of abnormal vibration of reciprocating compressor inlet pipelines during the commissioning of a booster station, the cause of severe vibration problem was investigated, which included modal analysis, calculation of resonant piping length, velocity frequency spectrum analysis, and pressure pulsation measurement. It was found that the inlet pipelines avoided low frequency resonance region, the actual length of the inlet pipelines was in the second resonant piping length, and the pressure pulsation far exceeded API 618 standard. The results indicate that large pressure pulsation and acoustic resonance occurred on the inlet pipelines are the key factors inducing vibration. Vibration elimination treatments included enlarging the buffer volume of gathering manifold, adjusting the inlet piping length to avoid acoustic resonance, and increasing the curvature radius of bend. After remodeling of the inlet pipelines, the test data indicate that the vibration level of the inlet pipelines is reduced to an acceptable level defined by a relevant standard, and the processing capacity of the booster station can be raised at least two times.

Identification of the Best Booster Station Network for a Water Distribution System

AbstractA fuzzy decision-making framework (DMF) is combined with a hybrid genetic algorithm–linear programming (GA-LP) optimization approach to determine the best booster station network for a water distribution system. The proposed hybrid GA-LP model simultaneously optimizes two conflicting objectives; namely, minimization of total chlorine injection dosage and the number of booster stations. At the same time, residual chlorine concentrations are kept within desired limits. Adjustment of the relative importance of two conflicting objectives results in different optimal solutions. Selection of the best alternative among these optimal solutions is performed through a fuzzy multiobjective DMF. The proposed DMF allows incorporation of the decision makers’ preferences into the booster station network design. In this study, three fuzzy objectives are selected based on economic, operational, and health-related concerns. The hybrid GA-LP model is applied to a case study, and results show that the proposed method...

Research of Mountain Area Wind Farm Grounding Scheme

Wind power has become one of the most potential and vital green energy sources. Location of the wind farm has a better wind resource，and it is also relatively open. Lightning accident in the wind farm happened occasionally, in order to avoid the situation, which impulse current damages the wind turbine, in the accident, lightning protection grounding system of wind turbine is essential .In this paper, according to the experience of Dongshan wind farm project , the method of how to design the wind turbines and booster station grounding grid as required, the calculation of ground resistance and specific measures to reduce grounding resistance of wind turbine grounding device are discussed.

CFD Modeling of Particulates Erosive Effect on a Commercial Scale Pipeline Bend

The computational fluid dynamics modeling of solid particles hydrodynamic based on the Lagrangian framework for diluted solid-gas flow through 90° gas pipeline bend is carried out to discover the effect of particles size distribution on particles flow pattern and their erosive effect on the bend. Particles size distribution has been obtained experimentally by measuring the sizes of solid particles that are flowing through the gas pipelines of Aghajari gas booster station. Also the erosion rate at the outer wall of the bend is predicted. The pipeline bend under study has a pipe diameter of 56 inches and ratios of the bend radius of the curvature to the pipeline diameter of 1.5. For the validation of computational model, firstly, the computational modeling is performed for a published experimental solid-gas flow data. The computational results include radial gas velocity and radial particle velocity profiles on planes which are at different angles through the bend. The comparison between the predicted numerical results and similar experimental data proves that the predictions of the computational model are acceptable. Finally, the particles' size distributions on each plane through the bend and the erosion rate on the outer wall of the bend have been obtained. The maximum rate of erosion is found to be 3.2 nm/s, occurring between 40 and 65° of the bend.

Application of Power Communication System in Wind Power Plant

The application of power communication system in the field of wind power mainly includes the overall system communication and local field communication. During the operation of wind farms, the total system requires that the electric power communication system should provide reliable rapid information channel, accuracy of transmission on a variety of digital business. This article will focus on the application of power communication system between the wind turbine and the booster station, which includes optical fiber communication, communication and leased public circuit, as well as the cable communication, wireless communication, microwave wireless communication. Finally, in the premise of various communications comparison, according to the actual situation of the wind power field, the network transmission rate and reliability should be considered to the requirements of power market.

Research Database of Water Distribution System Models

AbstractSince the 1960s, researchers have continued to develop new methodologies and algorithms in support of the planning, design, and management of water distribution systems. While initial research focused on modeling the hydraulics of such systems, the 1980s gave rise to additional research focus on water quality issues. More recent research has expanded into issues of system reliability and resilience, energy management, and sensor and chlorine booster station placement. In most cases, researchers have relied on either hypothetical water distribution systems or a handful of actual systems for use as benchmark test systems. Some of the more widely used actual systems include the New York tunnel system and the Hanoi water distribution system. This paper describes the development of a database of several water distribution systems synthesized from a statewide database of systems originally developed by the Kentucky Infrastructure Authority. The developed models include both small and medium networks, as...

A state-of-the-art review of techno-economic models predicting the costs of CO2 pipeline transport

This study aims to provide a systematic overview and comparison of capital and O&M costs models for CO2 pipelines and booster stations currently available in literature. Our findings indicate significantly large cost ranges for the results provided by the different cost models. Two main types of capital cost models for pipeline transport were found in literature, models relating diameter to costs and models relating mass flow to costs. For the nine diameter based models examined, a capital cost range is found of, for instance, 0.8–5.5M€2010/km for a pipeline diameter of 0.8m and a length of 25km. For the five mass flow based cost models evaluated in this study, a cost range is found of, for instance, 0.9–2.1M€2010/km for a mass flow of 750kg/s over 25km (TRUNK-25).An important additional factor is that all capital costs models for CO2 pipeline transport, directly or indirectly, depend on the diameter. Therefore, a systematic overview is made of the various equations and parameter used to calculate the diameter. By applying these equations and parameters to a common mass flow, height difference and length result in diameters between 0.59 and 0.91m for TRUNK-25. The main reason for this range was different assumptions about specific pressure drop and velocity. Combining the range for diameter, mass flow and diameter based cost models gives a capital and levelized cost range which varied by a factor 10 for a given mass flow and length. The levelized cost range will further increase if the discrepancy in O&M costs is added, for which estimations vary between 4.5 and 75€/m/year for a pipeline diameter of 0.8m.On top of this, most cost models underestimate the capital costs of CO2 pipelines. Only two cost models (namely the models who relate the costs to the weight of the pipeline) take into account the higher material requirements which are typically required for CO2 pipelines. The other sources use existing onshore natural gas pipelines as the basis for their cost estimations, and thereby underestimating the material costs for CO2 pipelines. Additionally, most cost models are based on relatively old pipelines constructed in the United States in the 1990s and early 2000s and do not consider the large increase in material prices in the last several years.Furthermore, key model characteristics are identified for a general cost comparison of CCS with other technologies and a system analysis over time. For a general cost comparison of CCS with other technologies, pipeline cost models with parameters which have physical or economic meaning are the preferred option. These are easy to interpret and can be adjusted to new conditions. A linear cost model is an example of such an model. For a system analysis over time, it is advised to adapt a pipeline cost model related to the weight of the pipeline, which is the only cost model that specifically models thickness of the pipeline and include material prices, to incorporate the effect of impurities and pipeline technology development. For modeling booster station costs, a relation between capacity and costs including some economies of scale seems to be the most appropriate. However, the cost range found in literature is very large, for instance, 3.1–3.6M€2010 for a booster station with a capacity of 1.25MWe. Therefore, validation of the booster station cost is required before such models are applied in further research.

Comparison of Construction Projects with Different Unit Wind Turbine Capacity

Development and utilization of renewable energy is important in optimize the power structure, save energy, protect environment, the development of low carbon economy has a positive role. Under the circumstances with wind machine price differ not big. The construction investment had little difference, under different capacity wind farm of the same capacity with different units. But when there is a bigger difference in wind machine price , it can be determination the rationality of the wind farm’s investment by the difference of the machine’ price preliminary. Also, it's available to estimate the whole investment. The wind farm 's permanent land area, according to the scale of wind farm, by estimating wind machines’, and the booster station, permanent land of transmission line and approach road area, then to determine the rationality of land area., on the basis of determining the wind farm project.

Resolving Problematic Biofilms in Buildings and Compounds

Biofilm problems persist in water distribution systems and, as a result, have been the focus of remediation strategy development. However, there have been limited reports of investigations of problematic biofilms in individual buildings and groups of buildings where biofilms may grow and affect a defined population. The authors have investigated three sites in subtropical areas—a school, a resort, and a condominium development. Each situation created different effects that were detected by the occupants and resulted in a water quality assessment. The common connection was problematic biofilm growth in the potable water distribution system resulting from site-specific incidents. In one case, the biofilm was formed as the system was not used for a long period. Another was a result of operational issues with the on-site water treatment process. The third case was caused by the water quality issues in the water delivered to the site. In each situation, solutions were sought to address the biofilm problem while keeping the buildings in service and reducing the potential for future recurrence. Applied control strategies included superchlorination and flushing, and were demonstrated to be effective. Operational strategies, including periodic pipe flushing and installation of a chlorine booster station, were recommended on a site-specific basis to prevent the return of problematic biofilms.

A bottom-up approach of stochastic demand allocation in water quality modelling

Abstract. An "all pipes" hydraulic model of a drinking water distribution system was constructed with two types of demand allocations. One is constructed with the conventional top-down approach, i.e. a demand multiplier pattern from the booster station is allocated to all demand nodes with a correction factor to account for the average water demand on that node. The other is constructed with a bottom-up approach of demand allocation, i.e., each individual home is represented by one demand node with its own stochastic water demand pattern. This was done for a drinking water distribution system of approximately 10 km of mains and serving ca. 1000 homes. The system was tested in a real life situation. The stochastic water demand patterns were constructed with the end-use model SIMDEUM on a per second basis and per individual home. Before applying the demand patterns in a network model, some temporal aggregation was done. The flow entering the test area was measured and a tracer test with sodium chloride was performed to determine travel times. The two models were validated on the total sum of demands and on travel times. The study showed that the bottom-up approach leads to realistic water demand patterns and travel times, without the need for any flow measurements or calibration. In the periphery of the drinking water distribution system it is not possible to calibrate models on pressure, because head losses are too low. The study shows that in the periphery it is also difficult to calibrate on water quality (e.g. with tracer measurements), as a consequence of the high variability between days. The stochastic approach of hydraulic modelling gives insight into the variability of travel times as an added feature beyond the conventional way of modelling.