Perdas de água em redes de distribuição acontecem por diversas razões, uma delas, o excesso de pressão, pode ser prevenido através da divisão das redes em Distritos de Medição e Controle. Este método vem sendo utilizado há algum tempo como modo de prevenir sobrepressão na rede, aumentando a confiabilidade e vida útil das tubulações e dispositivos do sistema. Atualmente, alguns autores propõem diferentes tipos de metodologias para uma eficiente definição de Distritos de Medição e Controle. Neste trabalho foi criada e aplicada uma metodologia baseada no estudo de uma área (Setor Aracy) na cidade de São Carlos - SP guiado por análise topográfica. A rede de distribuição do setor de abastecimento foi analisada indicando um subdimensionamento em alguns trechos, assim como, foi concluído que já existe uma setorização na área que não foi guiada por análise topográfica e sim por implantação dos loteamentos. Um estudo de setorização que tem como objetivo o gerenciamento de pressões deve ser norteado por análise da topografia do local juntamente com dispositivos gerenciadores de pressão (válvulas, boosters etc). / Water losses in network distribution systems may happen due to many reasons, one of them, the overpressure, can be prevented through the partitioning of these networks in District Metered Areas. This method has been used for some time as a way of preventing network overpressure, enhancing the reliability and lifespan of pipes and system devices. Currently, some authors propose different methodologies to an efficient delimitation of the District Metered Areas. In this work, a methodology was conceived and applied based on the study of an area (Aracy Sector) in the city of São Carlos - SP guided by topographic analysis. The distribution network of the supply sector was analyzed indicating an undersize in some pipes, as well as, it was concluded that a sectorization already exists in the area that is not guided by topographic analysis, but by the implementation of the allotments. A sectorization study that aims to manage pressures should be guided by topographic analysis of the site, together with pressure management devices (valves, boosters etc).

Perdas de água em redes de distribuição acontecem por diversas razões, uma delas, o excesso de pressão, pode ser prevenido através da divisão das redes em Distritos de Medição e Controle. Este método vem sendo utilizado há algum tempo como modo de prevenir sobrepressão na rede, aumentando a confiabilidade e vida útil das tubulações e dispositivos do sistema. Atualmente, alguns autores propõem diferentes tipos de metodologias para uma eficiente definição de Distritos de Medição e Controle. Neste trabalho foi criada e aplicada uma metodologia baseada no estudo de uma área (Setor Aracy) na cidade de São Carlos - SP guiado por análise topográfica. A rede de distribuição do setor de abastecimento foi analisada indicando um subdimensionamento em alguns trechos, assim como, foi concluído que já existe uma setorização na área que não foi guiada por análise topográfica e sim por implantação dos loteamentos. Um estudo de setorização que tem como objetivo o gerenciamento de pressões deve ser norteado por análise da topografia do local juntamente com dispositivos gerenciadores de pressão (válvulas, boosters etc). / Water losses in network distribution systems may happen due to many reasons, one of them, the overpressure, can be prevented through the partitioning of these networks in District Metered Areas. This method has been used for some time as a way of preventing network overpressure, enhancing the reliability and lifespan of pipes and system devices. Currently, some authors propose different methodologies to an efficient delimitation of the District Metered Areas. In this work, a methodology was conceived and applied based on the study of an area (Aracy Sector) in the city of São Carlos - SP guided by topographic analysis. The distribution network of the supply sector was analyzed indicating an undersize in some pipes, as well as, it was concluded that a sectorization already exists in the area that is not guided by topographic analysis, but by the implementation of the allotments. A sectorization study that aims to manage pressures should be guided by topographic analysis of the site, together with pressure management devices (valves, boosters etc).

Cluster randomized controlled trials are increasingly used to assess the effectiveness of life-style interventions in improvement of health services or prevention of disease. However, statistical methods in the analysis of cluster randomized controlled trials are not well established especially for analyzing binary outcomes. This project is motivated by the Community Hypertension Assessment Trial (CHAT) to assess the effectiveness of a 12-month community-based blood pressure management program in improving the management and monitoring of high blood pressure (BP) among older people. The study is a paired cluster randomized controlled trial, where the family physicians' practices are the clusters randomly allocated to CHAT intervention or usual practice, and a random sample of 55 patients 65 years and older were selected from the 14 practices in each study arm for health record review. The primary outcome was controlled BP over 12 months defined as systolic BP c:; 140 and diastolic BP c:; 90 for patients without diabetes or target organ damage or systolic BP c:; 130 and diastolic BP c:; 80 for patients with diabetes or target organ damage. Secondary outcomes include frequency of BP monitoring and average BP over a 12 month period. The clinical objective of this project is to evaluate the effectiveness of the CHAT intervention. The statistical objective is to compare Bayesian and classical methods of analyzing cluster-randomized trials using CHAT study as an example. We compared the results of different cluster-level analysis methods: i) un-weighted regression, ii) weighted regression, iii) random-effects meta-analytic approach, and different individual-level analyses: i) standard logistic regression, ii) robust standard errors approach, iii) generalized estimating equations, iv) random-effect logistic regression, v) Bayesian random-effect regression. We find that there is no sufficient evidence in support of the effectiveness of the CHAT intervention on all outcomes. For BP control, odds ratio (95% confidence interval) is 1.14 (0.72, 1.80) from generalized estimating equations. This result remains robust under different methods. We also find that the results from different statistical methods are different. The results from cluster-level analysis methods are quite different, while the results from the individual-level analysis methods are similar. We conclude that using various methods to analyze the trial provide good sensitivity analyses to help in interpreting the results of cluster randomized trials. Extensive simulation studies comparing the statistical powers of the different methods in different situations are required. / Thesis / Master of Science (MS)

La optimización de los sistemas de bombeo se suele realizar a través de las curvas características de la red (asociadas con las curvas resistentes). Estas curvas están sujetas a la resistencia generada por el usuario en función de las necesidades de caudal y presión en cada punto de consumo. Dicha resistencia es muy variable y difícil de determinar lo que hace que el cálculo de las curvas sea poco práctico. El problema radica en que al no definirse adecuadamente las curvas resistentes, no se conocen las necesidades reales de caudal y presión de la red. Por lo tanto no se puede estimar el exceso de energía aportado por las bombas ni el aumento de costos de operación que esto representa. Sin embargo, existe otro tipo de curva denominada curva de consigna (CC). Dicha curva ha sido poco estudiada hasta ahora y su cálculo es relativamente fácil. De ahí que el presente trabajo tiene como objetivo la optimización de la energía y de los costes de bombeo mediante el uso de la CC. Para cumplir con el objetivo, primero se estudia el cálculo de la CC en redes de agua con múltiples estaciones de bombeo, consumos no dependientes y dependientes de la presión, y sin tanques de almacenamiento. Posteriormente, se lleva a cabo la optimización sólo desde la perspectiva energética (caudal y altura de bombeo). Para ello se realiza la búsqueda de la distribución de caudales óptima entre las estaciones de bombeo que conlleve a las CC óptimas. Se proponen dos métodos: uno discreto (M-D) y otro continuo (M-C). El M-D considera la distribución de caudales como una variable discreta. La distribución óptima se obtiene de un conjunto de soluciones previamente definidas. En el M-C la distribución de caudales se asume como variable continua. La solución óptima viene dada por el uso de un algoritmo de optimización. Se han usado los algoritmos: Hooke-Jeeves y Nelder-Mead. El siguiente paso es la optimización de costos de operación (costos de bombeo y costos de producción de agua). Para ello se parte del M-C y se incluyen además las tarifas de energía, las tarifas de producción de agua y un criterio sobre el rendimiento mínimo esperado en las estaciones de bombeo. El último paso consiste en la optimización energética y de costos en redes con tanques. La inclusión de tanques implica la modificación del cálculo de la CC y por ende la metodología de optimización. En la función de costes se incluyen además de los costes de bombeo y de producción, costes de penalización por incumplimiento de presiones y de volúmenes de reserva. Al incluirse los tanques, incrementa el número de variables de decisión. Por lo que, es necesario el uso de algoritmos más potentes. Se han usado el Differential Evolution y el Hybrid Algorithm. Este último es un aporte añadido de este trabajo. La metodología de optimización se aplica a cinco redes de distribución: TF, Catinen, Coplaca, Anytown y Richmond. Los tanques sólo se consideran en las dos últimas redes. En el caso de la red TF se realiza una demostración sin entrar en profundidad de la selección de bombas a través del uso de las CC óptimas. Sin embargo, este paso está fuera de los límites de este trabajo. Tampoco se consideran condiciones de operación múltiples de la red, ni la fiabilidad en el caso de la remoción de tanques o sistemas de bombeo. No obstante, los resultados obtenidos evidencian que los sistemas de bombeo operados usando la CC pueden mejorar sus costos operativos hasta en un 12%. La metodología proporciona información sobre las estaciones de bombeo que representan mayores ahorros frente a aquellas que son menos importantes o innecesarias. Además, el método ha permitido demostrar que mejores condiciones de bombeo (bajas tarifas de energía y altos rendimientos) no siempre significan menores costos de operación. Finalmente, algunos resultados muestran la posible utilidad del método para optimizar tanto el uso como la ubicación de los tanqu / Usually, pumping optimisation in water distribution networks is carried out by means of the system head curves (SHCs), also known as the resistance curves (RCs). These curves are subjected to the resistance generated by the users, according with the flow and pressure head needs at the final points of demand. Such resistance is highly variable and hard to determine. Thus the calculation of the RCs and all the points that define them results impractical. As a RCs suitable calculation is not possible, real flow and pressure needs of the network are not known. Therefore, neither energy excess of the pumping regarding the real requirements nor the raising operating costs due to such excess, are estimated. However, there is another type of SHC defined as the setpoint curve (SC). It can be easily calculated, but has been poorly studied so far. Thus, this work aims the optimisation of the energy use and operating costs in pumping systems by using the SCs. To achieve the objective, first of all the SC calculation is studied for networks with several pumping stations, non-pressure driven demands, pressure-driven demands, and without tanks. Next, the optimisation is performed only from the energy point of view (i.e. flow and pumping head required). For that, a search of the optimum flow distribution among pumping stations to find the optimum SCs is performed. Two methods are proposed: the discrete (D-M) and the continuous (C-M). The D-M considers the flow distribution as a discrete variable. The optimum flow distribution is obtained from a set of solutions defined previously. In the C-M, the flow distribution is assumed as a continuous variable. The optimum solution comes from using optimisation algorithms. Two algorithms have been applied: Hooke-Jeeves and Nelder-Mead. Then, the cost optimisation (pumping cost and water production cost) is developed. For that purpose, the M-C is used as starting point. Then, energy tariffs, water production fares and the minimum expected efficiency at the pumping stations, are included. The last step consists in the energy and cost optimisation in networks with tanks. When tanks are included the SC calculation methodology changes. Hence, the optimisation process also does. In that sense, besides the costs of pumping and water production, the cost function also considers penalty costs for unaccomplished minimum pressures and minimum storage leves. Moreover, tanks inclusion also rises the number of decision variables. Thus, the use of more powerful algorithms is required. In that context, the Differential Evolution and the Hybrid Algorithm have been applied. The last one is an additional contribution of this work. The optimisation methodology is applied to five distribution networks: TF, Catinen, Coplaca, Anytown and Richmond. Tanks are only considered in the last two networks. In the case of TF network, demonstrative pumps selection (without going into great depth) by the optimum SCs application is done. However pumps sizing and selection study is out of the scope of this research. Neither multiple operation conditions nor reliability (i.e. in the case that tanks or pumping stations are removed), are considered. Nevertheless, the results obtained evidence that pumping systems operated by mean of the optimum SCs could reduce their operating costs up 12%. The methodology also gives information about which pumping stations represent major savings and which are less important or not needed. Besides, the method demonstrates that better pumping conditions (i.e. low energy tariffs and high efficiencies) not always mean lower operating costs. Finally, some results show that the method could be useful for the optimisation of both placement and use of storage tanks. / L'optimització dels sistemes de bombament se sol realitzar a través de les corbes característiques de la xarxa (associades amb les corbes resistents). Aquestes corbes estan subjectes a la resistència generada per l'usuari en funció de les necessitats de cabal i pressió en cada punt de consum. Aquesta resistència és molt variable i difícil de determinar el que fa que el càlcul de les corbes siga poc pràctic. El problema radica que al no definir-se adequadament les corbes resistents, no es coneixen les necessitats reals de cabal i pressió de la xarxa. Per tant no es pot estimar l'excés d'energia aportat per les bombes ni l'augment de costos d'operació que açò representa. No obstant açò, existeix un altre tipus de corba denominada corba de consigna (CC). Aquesta corba ha sigut poc estudiada fins ara i el seu càlcul és relativament fàcil. Per aquest motiu el present treball té com a objectiu l'optimització de l'energia i dels costos de bombament mitjançant l'ús de la CC. Per a complir amb l'objectiu, primer s'estudia el càlcul de la CC en xarxes d'aigua amb múltiples estacions de bombament, consums no depenents i dependents de la pressió, i sense tancs d'emmagatzematge. Posteriorment, es duu a terme l'optimització només des de la perspectiva energètica (cabal i altura de bombament). Per a açò es realitza la cerca de la distribució de cabals òptima entre les estacions de bombament que comporte a les CC òptimes. Es proposen dos mètodes: un de discret (M-D) i un altre continu (M-C). El M-D considera la distribució de cabals com una variable discreta. La distribució òptima s'obté d'un conjunt de solucions prèviament definides. En el M-C la distribució de cabals s'assumeix com a variable contínua. La solució òptima ve donada per l'ús d'un algorisme d'optimització. S'han usat els algorismes: Hooke-Jeeves i Nelder-Mead. El següent pas és l'optimització de costos d'operació (costos de bombament i costos de producció d'aigua). Per a açò es parteix del M-C i s'inclouen a més les tarifes d'energia, les tarifes de producció d'aigua i un criteri sobre el rendiment mínim esperat en les estacions de bombament. L'últim pas consisteix en l'optimització energètica i de costos en xarxes amb tancs. La inclusió de tancs implica la modificació del càlcul de la CC i per tant la metodologia d'optimització. En la funció de costos s'inclouen a més dels costos de bombament i de producció, costos de penalització per incompliment de pressions i de volums de reserva. En incloure's els tancs, incrementa el nombre de variables de decisió. Pel que, és necessari l'ús d'algorismes més potents. S'han usat el Differential Evolution i el Hybrid Algorithm. Aquest últim és una aportació afegida d'aquest treball. La metodologia d'optimització s'aplica a cinc xarxes de distribució: TF, Catinen, Coplaca, Anytown i Richmond. Els tancs només es consideren en les dues últimes xarxes. En el cas de la xarxa TF es realitza una demostració sense entrar en profunditat de la selecció de bombes a través de l'ús de les CC òptimes. No obstant açò, aquest pas està fora dels límits d'aquest treball. Tampoc es consideren condicions d'operació múltiples de la xarxa, ni la fiabilitat en el cas de la remoció de tancs o sistemes de bombament. No obstant açò, els resultats obtinguts evidencien que els sistemes de bombament operats usant la CC poden millorar els seus costos operatius fins a en un 12%. La metodologia proporciona informació sobre les estacions de bombament que representen majors estalvis enfront d'aquelles que són menys importants o innecessàries. A més, el mètode ha permès demostrar que millors condicions de bombament (baixes tarifes d'energia i alts rendiments) no sempre signifiquen menors costos d'operació. Finalment, alguns resultats mostren la possible utilitat del mètode per a optimitzar tant l'ús com la ubicació dels tancs d'emmagatzematge. / León Celi, CF. (2018). Optimisation of both energy use and pumping costs in water distribution networks with several water sources using the setpoint curve [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107956

A fast and efficient method to calculate time schedules for internal and boundary PRVs and flow modulation curves has been developed and implemented. Both time and flow modulation can be applied to a single inlet DMA. The time modulation methodology is based on solving a nonlinear programming problem (NLP). In addition, Genetic Algorithms (GA) has been proposed and investigated to calculate the optimal coefficients of a second order relationship between the flow and the outlet pressure for a PRV to minimize the background leakage. The obtained curve can be subsequently implemented using a flow modulation controller in a feedback control scheme. The Aquai-Mod® is a hydraulic device to control and modulate the outlet pressure of a PRV according to the valve flow. The controller was experimentally tested to assess its performance and functionality in different conditions and operating ranges. The mathematical model of the controller has been developed and solved, in both steady state and dynamic conditions. The results of the model have been compared with the experimental data and showed a good agreement in the magnitude and trends. A new method for combined energy and pressure management via integration and coordination of pump scheduling with pressure control aspects has been created. The method is based on formulating and solving an optimisation NLP problem and involves pressure dependent leakage. The cost function of the optimisation problem represents the total cost of water treatment and pumping energy. Developed network scheduling algorithm consists of two stages. The first stage involves solving a continuous problem, where operation of each pump is described by continuous variable. Subsequently, the second stage continuous pump schedules are discretised using heuristic algorithm. Another area of research has been developing optimal feedback rules using GA to control the operation of pump stations. Each pump station has a rule described by two water levels in a downstream reservoir and a value of pump speed for each tariff period. The lower and upper water switching levels of the downstream reservoir correspond to the pump being “ON” or “OFF”. The achieved similar energy cost per 1 Ml of pumped water. In the considered case study, the optimal feedback rules had advantage of small number of ON/OFF switches, which increase the pump stations lifetime and reduce the maintenance cost as well.

This study aims to develop an integrated methodology for finding water leaks in a water distribution network. The integrated methodology is formed from SCADA System, Customer Information System (CIS), and Geographic Information System. The methodology is based on forming district-metered areas (DMA) and sub-DMAs in pressure zones by isolation of the network. Leaking spots in the network are localised by step testing within the DMA. With leak noise loggers leaking spots are localized with an increased accuracy and finally pinpointed by ground microphones. Minimum night flows are observed from the SCADA system before and after the repairs of the leaks to calculate physical water loss percentage in the DMA. Monthly non-revenue water percentage is calculated using the data obtained from SCADA and CIS. With a buffer analysis on the water distribution network data, the benefit of the leak noise loggers is maximized and the working time with the ground microphones are minimized. The methodology is applied in two different DMAs in Antalya water distribution network with different characteristics. In the first DMA, only the developed methodology is applied and a decrease of 19.2% is achieved in physical water losses. In the second DMA, pressure reduction is added to the methodology and a decrease of 4.9% is achieved.

For the appropriate operation and correct short term planning, daily demand curve (DDC) of municipal water distribution networks should be forecasted beforehand. For that purpose, artificial neural networks (ANN) is used as a new method. The proposed approach employs already recorded DDCs extracted from the database of ASKI (Ankara Water Authority) SCADA center and related independent parameters such as temperature and relative humidity obtained from DMI (State Meteorological Institute). In this study, a computer model was developed in order to forecast hourly DDCs using Matlab and related modules. Parameters that affect the consumption of the water were determined as temperature, relative humidity, human behavior (weekend or workday) and season. Randomly selected days were taken into account for performance of the ANN model. Forecasted DDC values were compared with recorded data and consequently the model gives relatively satisfactory results, an average of 75% match according to R2 values for Ankara N8-3 network. Same architecture was applied for Antalya network give better results, average of 85%. For planning purposes / total volume and peak water consumption values for the selected recorded days, the day before recorded days, ANN forecasted days and seasonal average was compared and seasonal average gave relatively better results. Using the forecasted DDC, (i) performance analysis of the pressure zone and (ii) optimum valve setting evaluation for pressure management were realized. The results of the study may help water utilities for short term planning of a water distribution network, rehabilitation of elements, taking counter measures and setting the valve openings for minimizing leakage and optimizing customer conformity of the distribution network.

For the appropriate operation and correct short term planning, daily demand curve (DDC) of municipal water distribution networks should be forecasted beforehand. For that purpose, artificial neural networks (ANN) is used as a new method. The proposed approach employs already recorded DDCs extracted from the database of ASKI (Ankara Water Authority) SCADA center and related independent parameters such as temperature and relative humidity obtained from DMI (State Meteorological Institute). In this study, a computer model was developed in order to forecast hourly DDCs using Matlab and related modules. Parameters that affect the consumption of the water were determined as temperature, relative humidity, human behavior (weekend or workday) and season. Randomly selected days were taken into account for performance of the ANN model. Forecasted DDC values were compared with recorded data and consequently the model gives relatively satisfactory results, an average of 75% match according to R2 values for Ankara N8-3 network. Same architecture was applied for Antalya network give better results, average of 85%. For planning purposes / total volume and peak water consumption values for the selected recorded days, the day before recorded days, ANN forecasted days and seasonal average was compared and seasonal average gave relatively better results. Using the forecasted DDC, (i) performance analysis of the pressure zone and (ii) optimum valve setting evaluation for pressure management were realized. The results of the study may help water utilities for short term planning of a water distribution network, rehabilitation of elements, taking counter measures and setting the valve openings for minimizing leakage and optimizing customer conformity of the distribution network.

Thermochemical heat storage (TCS) is a thermal energy storage (TES) technology used to store thermal energy for later use. TCS can provide heating or cooling services from intermittently available thermal energy, often low grade waste heat. The system studied here stores and releases the energy in the form of chemical energy by utilizing reversible chemical reactions. TCS has potential to reduce greenhouse gas emissions, increase infrastructure system efficiency, lower society-wide energy system costs and by that contribute to sustainable development. This thesis is part of a joint TCS research project named Neutrons for Heat Storage (NHS), involving three research institutes. The project is funded by Nordforsk and KTH Royal Institute of Technology. KTH´s objective in the NHS project is to design, build and operate a bench-scale TCS system using strontium chloride (SrCl2) and ammonia (NH3) as a solid-gas reaction system for low-temperature heat storage (40-80 ℃). Here, absorption of NH3 into SrCl2⋅NH3 (monoammine) to form SrCl2⋅8NH3 (octaammine) is used for heat release, and desorption (of NH3 from SrCl2⋅8NH3 to form SrCl2⋅NH3) for heat storage. Prior to this thesis project, this TCS system, as well as its reactor+heat exchanger (R-HEX) units, were numerically designed at KTH, and the R-HEX units were manufactured. This system is now being built at the laboratory of Applied Thermodynamics and Refrigeration division at the Department of Energy Technology, KTH. The initial system is comprised of a shared storage tank, expansion valve, ammonia meter and an R-HEX (absorption path); and an R-HEX, ammonia meter, gas cooler, compressor, condenser, and the storage tank (desorption path), to accommodate absorption, desorption, and NH3 storage. This thesis was originally planned to include commissioning, operation and experimental data acquisition, and performance evaluation of this system. However, due to various delays and shortcomings discovered at the beginning of the project, its objectives were then redefined to review the system and its components and propose necessary design adaptations of the initially designed (and partially built) system. This thesis project was partly a joint project, where Harish Seetharaman performed various tasks in the overarching NHS project as part of his own thesis project, performed alongside the work described in this report. For various information and results, referring to Harish´s report therefore will be necessary. A literature review of the research into SrCl2-NH3 systems was conducted, with emphasis on performance evaluation, kinetics, and reaction paths. TES performance evaluation is discussed concerning the TCS key performance indicators, with the 2018 IEA's Annex 30 as a guideline and 2013 IRENA´s E17 technology brief as a comparative reference. Much progress and refinement has been made in the 5-year span between the publications of these documents, but some adaptations and interpretations still need to be made to the Annex 30 approach for a good approach to a TCS system of similar nature as the one studied in this report. Review of the latest research on the kinetics and reaction path of the SrCl2-NH3 reaction pair revealed that the 100-year-old single-line-and-path reaction expression is an oversimplification of the actual chemistry. The reaction path seems to be dependent on the kinetics of the reaction, and varies with heating rate, temperature, and pressure. Various literature was found and compared, which show that the reaction enthalpies and entropies are not settled science. This demonstrates the necessity for further research into the SrCl2-NH3 reaction pair before application-scale product design and commercialization can take place. A comprehensive equipment and system review was conducted, whereby multiple issues were found and addressed, that if gone unnoticed, would have caused difficult setbacks for the project.  Consequently, the previous purchased ammonia flow meters and ammonia compressor, were exchanged for new and better suiting equipment. The original ammonia flow meters were undersized due to miscalculations of converting flow units of NLPH (Normal Liters Per Hour) to the project units of g/s, while wrongly using the density of compressed ammonia to convert to g/s, instead of it at the defined normal conditions. Furthermore, these flow meters were of the wrong type, as they had no digital output for data acquisition. The original compressor was also severely undersized, only capable of evacuating 7-14% of the expected maximum desorption flow. This was due to a similar miscalculation during conversion of NLMP (Normal Liters Per Minute) to g/s, as well as an unrequested compressor stroke reduction. New solutions and additional equipment were then required to accommodate the operational limitations discovered in the final chosen equipment and system configuration. These include limiting the compressor inlet pressure to a maximum of 1.1 bar(a); avoiding risk of NH3 condensation at them inlets of the new mass flow meters and compressor; and maintaining the flow meter and compressor inlet temperatures below 40 °C. The pressure limitations required considerable design adaptations. Firstly, an ammonia by-pass is introduced to keep feeding ammonia into the compressor during low desorption flows. The inlet pressure limitation necessitated active pressure management in the form of pressure reduction valves, which were thus introduced. Secondly, the condensation regulation and temperature management required a new approach, as the cooling and condensation temperatures in the original design were too low, causing risks of far too low temperature and pressure in the desorption path, as well as counter-acting simultaneous heating and cooling between the condenser and the storage tank heating sleeve. As a solution, a shunt pump is proposed, where constant cooling water temperature provides condensation on a tight temperature range using an infinite cold wall approach. Along with reviewing the equipment and the system design, new procedures concerning investigating and confirming homogeneous heat transfer properties of the reactors are proposed. Furthermore, improvements are suggested concerning the commissioning of the experimental rig, that include equipment testing with N2-gas and stepwise changes in temperature in sequential cycles to gain a good understanding of the likely behaviors of the system before it is run at the extremes of the operating range. In conclusion, a new and improved process flow diagram, showing all these adaptations, additions, and changes from the original diagram is presented herein as the final key contribution to the overarching NHS-project. This is complemented with an instruction manual, to allow the next researchers a smooth continuation, in terms of the system build, and later commissioning and operation. Finally, some suitable next steps in the project are suggested. These include a conceptualization of descriptive functions for the performance and behavior of the specific system and reactors. These functions are proposed with temperature and pressure as independent variables, as these are two main variables influencing the kinetics of the reaction in the given system. As no experimental data exists yet, the form of the proposed functions is generic. Furthermore, a suggestion is made for a future adaptation for achieving the phase change from NH3(g) to NH3(l) (which is the storage form of ammonia in the system) by deep cooling at the desorption pressure, resulting in only a liquid pump being required to raise the pressure of the NH3(l) in the storage tank. / Termokemisk energilagring (TCS) är en teknik inom termisk energilagring (TES) som används för att lagra termisk energi för senare bruk. TCS kan tillhandahålla värme och kyla från periodvis tillgänglig termisk energi, ofta lågtemperatur spillvärme. Systemet lagrar energin som kemisk energi genom att använda reversibla kemiska reaktioner och massaseparation av reaktions-produkterna. TCS har potential att minska utsläppet av växthusgaser, öka effektiviteten av system i vår infrastruktur, minska energikostnader i samhället och därmed bidra till hållbar utveckling. Detta exjobbsprojekt är en del av ett gemensamt TCS-forskningsprojekt som heter Neutrons for Heat Storage (NHS), där tre forskningsinstitut deltar. Projektet är finansierat av Nordforsk och Kungliga Tekniska Högskolan. KTH:s mål med NHS-projektet är att projektera, bygga, samt driva ett TCSsystem i bänkskala med strontiumklorid (SrCl2) och ammoniak (NH3) som ett fast-gasreaktionssystem för lågtemperaturvärmelagring (40-80 ℃). Här används absorption av NH3 till SrCl2⋅NH3 (monoammin) för att bilda SrCl2⋅8NH3 (oktaammin) för värmeurladdning och desorption (av NH3 från SrCl2⋅NH3 till SrCl2⋅NH3) för värmelagring. Innan detta exjobbsprojekt började hade detta TCS-system, samt systemets reaktor+värmeväxlare (R-HEX) enheter varit numeriskt projekterad vid KTH, och R-HEX-enheterna hade redan tillverkats. Detta system byggs nu på laboratoriet för Avdelningen för tillämpad termodynamik och kylning vid Institutionen för Energiteknik, KTH. Det initiala systemet består av en gemensam lagringstank, expansionsventil, ammoniakmätare, och en R-HEX (systemets absorptionssida) och en R-HEX, ammoniakmätare, gaskylare, kompressor, en kondensor, och en gemensamma lagringstanken (desorptionssidan), for att rymma absorption, desorption (samtidigt) och NH3-lagring. Exjobbsprojektet var ursprungligen planerat att inkludera driftsättning, drift och experimentdatainsamling samt utvärdering av systemet. På grund av olika förseningar och brister som upptäcktes i projektet, omdefinierades projektets mål och består nu av att granska systemet och, samt att föreslå nödvändiga designanpassningar av det ursprungligen konstruerade systemet och dess komponenter. Projektet var delvis ett gemensamt arbete, där Harish Seetharaman utförde olika uppgifter i det övergripande NHS projektet som en del av sitt eget exjobbssprojekt. För olika uppgifter och resultat kommer det därför att vara nödvändigt att hänvisa till Harishs rapport. Litteraturstudié av forskningen kring SrCl2-NH3 system genomfördes, med betoning på prestandautvärdering, kinetik och reaktionsvägar. Prestandautvärdering av TES system diskuteras angående TCS-nyckelindikatorer, med 2018 års IEA:s Annex 30 som riktlinje och IRENA:s E17 Teknologi-sammandrag från 2013 som en referens. Många framsteg och förbättringar har gjorts under femårsperioden mellan dessa publikationer, men vissa anpassningar och tolkningar måste fortfarande härledas till metoderna i Annex 30 för att få ett bra förhållningssätt till ett TCS-system av liknande karaktär som det som studeras i detta projekt. Granskning av den senaste forskningen avseende reaktionskinetik och reaktionsvägar för SrCl2-NH3 reaktionsparet visade att det hundraåriga enkellinje-och-reaktionsväg-formuleringen är en förenkling av den faktiska kemin. Reaktionsvägen verkar beroende av reaktionens kinetik och varierar med uppvärmnings-takten, temperaturen och även trycket. Olika litteratur jämfördes som visar att reaktionsentalpierna och entropierna inte är fastställd vetenskap. Detta visar behovet av ytterligare forskning avseende SrCl2-NH3 innan produktdesign och kommersialisering i applikations-skala kan utföras. En omfattande granskning av systemet och dess komponenter genomfördes, där flera problem hittades och åtgärdades. Om dessa problem hade gått obemärkt förbi skulle det ha orsakat svåra bakslag för projektet. Följaktligen byttes de tidigare köpta ammoniakflödesmätarna ut till nya och en ammoniakkompressor byttes ut mot en ny, för tillämpningen bättre anpassad. De ursprungliga ammoniak-flödesmätarna var underdimensionerade pga. felberäkningar i omvandling av flödesenheter för NLPH (normal liter per timme) till projektenheterna g/s. Samtidigt var densiteten av komprimerad ammoniak felaktigt använt för omvandling till g/s, istället för densiteten vid de definierade normala förhållandena; 1 bar (a) och 20 ° C. Dessutom var dessa flödesmätare av fel typ, eftersom de inte hade någon digital utgång för datainsamling. Den ursprungliga kompressorn var också kraftigt underdimensionerad, endast kapabel att evakuera 7-14% av det förväntade maximala desorptionsflödet. Detta berodde på en liknande felberäkning vid konvertering av NLPM (normal liter per minute) till g/s, samt en oönskad kompressorslagsminskning. Nya lösningar och ytterligare utrustning krävdes för att tillgodose de operativa begränsningar som upptäcktes i den slutgiltigt valda utrustningen och systemutformningen. Dessa inkluderar: begränsa kompressorns inloppstryck till maximalt 1,1 bar(a); undvika risk för NH3 kondens i de nya massflödesmätarna och kompressorn; samt bibehålla flödesmätarens och kompressorns inloppstemperaturer under 40 °C. Tryckbegränsningarna krävde omfattande projekteringsanpassningar. För det första införs en ammoniak-by-pass för att fortsätta mata ammoniak till kompressorn under låga desorptionsflöden. Inloppstrycksbegränsningen nödvändiggjorde aktiv tryckhantering i form av tryckreduceringsventiler. För det andra krävde kondensregleringen och temperaturhanteringen en ny strategi, eftersom kyl- och kondenseringstemperaturerna i den ursprungliga utformningen var för låga. Detta orsakade risker för alldeles för låg temperatur och tryck på desorptionssidan, samt samtidigt motverkande uppvärmning och kylning av kondensorn och förvaringstankens värmehylsa. Som en lösning föreslås en shunt där konstant kylvattentemperatur ger kondens i ett tätt temperaturintervall med en oändlig kallväggsinriktning. Tillsammans med granskning av utrustningen och systemutformningen föreslås nya tillvägagångssätt för undersökning och bekräftelse av reaktorers förmodade homogena värmeöverförings-egenskaper. Dessutom föreslås förbättringar av idrifttagningen av den experimentella riggen, som inkluderar utrustningstestning med N2-gas och stegvisa temperaturförändringar i sekventiella körningar för att få en god förståelse för systemets troliga beteenden innan det körs i ytterligheterna av systemts arbetsområde. Sammanfattningsvis presenteras ett nytt och förbättrat processflödesdiagram, som visar alla utförda anpassningar, tillägg och ändringar från det ursprungliga diagrammet, som är avhandlingsprojektets huvudbidrag till det övergripande NHS-projektet. Detta kompletteras med en bruksanvisning för att smidigt fasa in kommande forskare avseende systemets konstruktion, driftsättning, och drift. Slutligen föreslås några lämpliga kommande steg i projektet. Dessa inkluderar en konceptualisering av beskrivande funktioner för prestanda och beteende av det specifika systemet och reaktorer. Dessa funktioner föreslås med temperatur och tryck som oberoende variabler, eftersom dessa är två huvudvariabler som påverkar reaktionens kinetik. Eftersom inga experimentella data ännu finns, är formen för de föreslagna funktionerna generisk. Vidare ges förslag om framtida anpassning för att uppnå fasändringen från NH3(g) till NH3(v) (som är lagringsformen för NH3 i systemet) genom djup nedkylning vid desorptionstrycket, vilket resulterar i att endast en vätskepump krävs för att höja trycket för NH3(v) i lagringstanken.