Energy Recovery Systems Research Papers (original) (raw)

2025

A scrollwrap profile is an important factor affecting the performance and reliability of scroll fluid machines. A number of geometric curves have been used to form the working surfaces of the scroll machines. The involute of a basic... more

2025, Water Science and Technology

In light of global warming mitigation efforts, increasing sludge disposal costs, and need for reduction in the carbon footprint of wastewater treatment plants, innovation of treatment technology has been tailored towards energy self-sufficiency. The AB process is a promising technology to achieve maximal energy recovery from wastewaters with minimum energy expenditure and therefore inherently reducing excess sludge production. Characterization of this novel sludge and its comparison with the more conventional B-stage sludge are necessary for a deeper understanding of AB treatment process design. This manuscript presents a case study on a pilot-scale AB system treating municipal wastewaters as well as a bio-(biochemical methane potential and adenosine tri-phosphate analysis) and physico-chemical properties (chemical oxygen demand, sludge volume index, dewaterability, calorific value, zeta potential and particle size distribution) comparison of the organic-rich A-stage against the B-stage activated sludge. Compared to the B-sludge, the A-sludge yielded 1.4 to 4.9 times more methane throughout the 62-weeks operation.

2025, Water science and technology : a journal of the International Association on Water Pollution Research

In light of global warming mitigation efforts, increasing sludge disposal costs, and need for reduction in the carbon footprint of wastewater treatment plants, innovation in treatment technology has been tailored towards energy self-sufficiency. The AB process is a promising technology for achieving maximal energy recovery from wastewaters with minimum energy expenditure and therefore inherently reducing excess sludge production. Characterization of this novel sludge and its comparison with the more conventional B-stage sludge are necessary for a deeper understanding of AB treatment process design. This paper presents a case study of a pilot-scale AB system treating municipal wastewaters as well as a bio- (biochemical methane potential and adenosine tri-phosphate analysis) and physico-chemical properties (chemical oxygen demand, sludge volume index, dewaterability, calorific value, zeta potential and particle size distribution) comparison of the organic-rich A-stage against the B-st...

2025, Sustainability

Currently, society is facing a great environmental problem, due to the large amount of plastic waste generated, most of which is not subjected to any type of treatment. In this work, polyethylene film waste from the non-selectively collected fraction was catalytically pyrolyzed at 500 °C, 20 °C/min for 2 h, in a discontinuous reactor using nitrogen as an inert gas stream. The main objective of this paper is to find catalysts that decrease the viscosity of the liquid fraction, since this property is quite meaningful in thermal pyrolysis. For this purpose, the three products of catalytic pyrolysis, the gaseous fraction, the solid fraction and the liquid fraction, were separated, obtaining the yield values. After that, the aspect of the liquid fraction was studied, differentiating which catalysts produced a larger quantity of waxy fraction and which ones did not. The viscosity of these samples was measured in order to confirm the catalysts that helped to obtain a less waxy fraction. Th...

2025

In this work the issue of treatment of coke plant wastewater. The aim of this work was to study environmental pollution caused by emissions and effluents of coke plants to develop technologies to prevent penetration of hazardous substances into the water basin. Field studies were conducted, and the main sources of pollution, their chemical composition and concentrations were determined. In addition, mechanism of adsorption purification of effluents from particularly hazardous chemicals were developed.

2025, … homepage: www. IJEE …

Environmental degradation and depleting fuel reserves are matters of great concern around the global. Solid waste plastic is currently receiving renewed interest for fuel generation. Waste plastic to fuel is suitable for compression ignition engines and more attention is focused in the world because of its potential to generate large-scale employment and relatively low environmental degradation. A postcommercial PS polymer waste was thermal degradation and fractional distillation without catalysts using a steel reactor operating thermally at ambient pressure under fume hood without vacuum system. Two types of temperature profile was used for this experiment such as PS waste plastic liquefaction purposed temperature used 100-400 ºC and fractional column distillation temperature was used 180-305 ºC for collection kerosene or aviation grade fuel. Produced fuel was analyzed by using gas chromatography and mass spectrometer and fuel hydrocarbon range showed into GC/MS analysis is C 6 to C 16 .

2025, Ingenieria Civil

La desalación de agua de mar tiene por objeto producir agua apta para cualquier uso a partir de agua marina. El agua de mar se caracteriza por su elevado contenido de sales en diso-lución, las cuales deben ser eliminadas en su práctica totalidad. Según las leyes físicas que rigen el comportamiento de las disoluciones, esta separación requiere una considerable aplicación de energía. El presente artículo pretende sintetizar las bases físicas del consumo energético en la desalación de agua de mar por ósmosis inversa, examinar el consumo actual de energía de la industria española del sector, y analizar las perspectivas de reducción de consumo que puede ofrecer el desarrollo tecnológico en los próximos años. El consumo de energía en la desalación de agua de mar por ósmosis inversa: situación actual y perspectivas ANTONIO ESTEVAN (*) y MANUEL GARCÍA SÁNCHEZ-COLOMER (**) ENERGY CONSUMPTION IN REVERSE OSMOSIS SEAWATER DESALINATION: CURRENT SITUATION AND PERSPECTIVES ABSTRACT This article shows a calculation of the specific consumption generated during the process of reverse osmosis in a seawater desalination plant, by two different systems of energy recovery: Pelton turbines and isobaric chambers. Ideal physical consumption and minimal industrial consumption are defined, and compared with the real consumptions registered in four seawater desalination plants in Spain. Finally, the margins to reduce the energy consumptions in this process and the current tendencies in framework of technological progress are examined. With a work pressure of 70 atm and a conversion index of 45 %, the ideal physical consumption reaches 1,97 kWh/m 3 . In a context of the best available technology, with ideal assembly and operation, the minimal industrial consumption applying Pelton turbines is 2,74 kWh/m 3 , whereas with isobaric chambers goes down up to 2,51 kWh/m 3 . The ideal consumptions calculated for plants with Pelton turbines in real assembly and operation change between 2,9 and 3,1 kWh/m 3 . This analysis concludes that the available margins to reduce the energy consumptions are already quite limited, because the principal Spanish desalination plants rise above optimal consumptions calculated in the reverse osmosis phase in a margin changing between a 9% and 14%. In the short term the possibility of the widespread use of isobaric chambers instead of Pelton turbines is considered, together with a small reduction of the work pressure, and some improving in the architecture of the desalination plants. (*) Grupo de Estudios y Alternativas 21, S.L. (GEA21). (**) Centro de Estudios de Técnicas Aplicadas del CEDEX. RESUMEN En este artículo se realiza un cálculo del consumo específico generado durante el proceso de ósmosis inversa en una planta desaladora de agua de mar, en dos diferentes escenarios de recuperación de energía, mediante turbinas Pelton y mediante las denominadas cámaras isobáricas. Se definen el consumo físico ideal y el consumo mínimo industrial y se comparan con los consumos registrados en funcionamiento real en cuatro plantas desaladoras de agua de mar instaladas en España. Finalmente se examinan los márgenes para reducir los consumos energéticos en este proceso y las tendencias actuales en materia de eficiencia energética en el sector. Con una presión de trabajo de 70 atm y un índice de conversión del 45%, el consumo físico ideal alcanza 1,97 kWh/m 3 . En un contexto de la mejor tecnología actualmente disponible, con ensamblaje y operación ideales, el consumo mínimo industrial aplicando turbinas Pelton es de 2,74 kWh/m 3 , mientras que con cámaras isobáricas baja hasta 2,51 kWh/m 3 . Los consumos óptimos calculados para plantas con turbinas Pelton con ensamblaje y operación reales se sitúan en una horquilla de 2,9 a 3,1 kWh/m 3 . A la luz del análisis realizado se concluye que los márgenes disponibles para disminuir los consumos energéticos son ya bastante reducidos, dado que las principales plantas españolas superan los consumos óptimos calculados en la fase de ósmosis en un margen que varía entre un 9% y un 14%. A corto plazo se contempla la posibilidad de la utilización generalizada de cámaras isobáricas en lugar de turbinas Pelton, junto con una pequeña reducción de la presión de trabajo, y ciertos perfeccionamientos en la arquitectura de las plantas desaladoras.

2025, Journal of Thermal Analysis and Calorimetry

Pyrolysis of polymers with widespread use, such as PET, HDPE, PVC, LDPE, PP and PS, been utilized extensively as plastic packaging materials, is the subject of this study. Low biodegradability and short life of polymers used in packaging have resulted in enormous waste amounts; thus, polymer recycling is more than imperative for modern, developed municipalities. One of the main problems is the production of either feedstock or valuable secondary materials, without additional environmental burden. In this context, the thermochemical methods lead not only to recycling of plastics but also to the creation of specific petrochemical industrial products, and the profit will be considerable. Pyrolizer accompanied by a GC/MS is a useful instrumental array for the study of the thermal degradation of several types of polymers. It is resulted that the cracking temperature affects the type and number of the segments produced, since higher temperatures strongly parcel the polymer chain to monomers and release smaller molecules, while at lower temperatures it is more likely to detect oligomers. Chromatographic results were sometimes complicated due to the isomers produced during pyrolysis. It is mainly supposed that polyolefins decompose through a radical process, where depolymerization propagates until H-abstraction occurs. PVC behaves differently due to the presence of halogens, fond to chain reactions, while for PS the main fragments eluted are styrene monomer, dimmer and trimmer. From PET analysis, it is concluded that the products of decomposition include CO 2 , PhCOOH, PhCOOCH = H 2 and other aromatic vinyl-substitutes, while PET depolymerization is keen on CaO catalysis for lower decomposition temperatures.

2025, International Journal of Engineering Research & Technology

The increasing global energy demand and environmental concerns necessitate the development of efficient renewable energy systems. While geothermal and solar power plants have been studied separately, limited research exists on their integration and optimization. This paper advances the understanding of hybrid renewable systems by analysing a binary geothermal-solar power plant using an Organic Rankine Cycle (ORC), focusing on its thermodynamic and exergy performance. The system uniquely combines solar thermal collectors with geothermal resources, where a heat transfer fluid from the solar collector vaporizes the working fluid for power generation, while geothermal brine is maintained at 70°C before reinjection to prevent silica formation and source cooling. Through comprehensive exergy analysis, this study examines the environmental impact of energy exploration and generation using thermodynamic parameters. The research compares the system's performance using two working fluids, Toluene and Isobutane, revealing that working fluid selection significantly influences system energy efficiency and gross electricity generation. Results demonstrate that at a mass flow rate of 0.3 kg/s, Toluene achieves approximately 70% efficiency compared to Isobutane's 60%, providing valuable insights for optimizing hybrid geothermal-solar power systems.

2025

Catalytic pyrolysis of plastic wastes is a promising way for their conversion into valuable products. By modulating the catalyst properties and operating conditions, it is possible to direct the product distribution to obtain oils which can be suitable as both fuels or chemicals. However, the efficient and safe removal of the halogens, often contained in plastic wastes, remains as a great challenge. In this work, the catalytic behaviour of ZSM-5 zeolites in the pyrolysis of a real chlorinated plastic waste of the electric and electronic equipment sector (WEEE), consisting of PE with about 3.4% of PVC was investigated. To that end, three zeolite samples with different acidity and accessibility were synthesized and assayed. A thermal pre-treatment was applied to the plastic waste at 350 ºC, which allowed a chlorine removal of 87% from the WEEE feedstock. The pyrolysis tests were carried out in a downdraft fixed-bed stainless steel reactor, with catalyst/feedstock ratio of 0.2, at temperatures of 600 ºC and 450 ºC in the thermal and catalytic zones, respectively, of the reaction system. In comparison with thermal pyrolysis, that mainly produced waxes, the product distribution changed considerably by contacting the pyrolysis vapours with ZSM-5 zeolites, leading to a strong enhancement in the yield of oil and gases. The largest yield of oil (about 60 wt.%), having a concentration of monoaromatics (mainly BTX) above 50 wt.%, was attained over the desilicated ZSM-5 sample. Regarding chlorine distribution, about 90% was accumulated in the char fraction, probably captured by the inorganic components present in the raw WEEE waste. Coke was the second fraction in terms of Cl concentration, followed by wax and oil, whereas this halogen was almost not detected in the gases. The lowest concentration of Cl in the oil was attained with the desilicated zeolite, with a value below 90 ppm, which could facilitate the subsequent processing of this stream in refinery units.

2025

This research presents a comprehensive framework for the sustainable management of Municipal Solid Waste (MSW) and its conversion into valuable products and electricity. This study aims to optimize the MSW management system and identify the optimal pathway for handling MSW, employing Mixed-Integer Nonlinear Programming (MINLP) model. The framework includes data collection, mathematical modeling, and a case study of Pakistan. In the analysis of 15 cities in Pakistan, the authors found that the most profitable pathway involves the recycling of recyclable materials, followed by transesterification for biodiesel production. This approach yielded an average profit of 7367per100tonsofMSW.Theauthorsalsoinvestigatedascenariowithoutrecycling,whereonlytransesterificationwasemployed,resultinginanaverageprofitof7367 per 100 tons of MSW. The authors also investigated a scenario without recycling, where only transesterification was employed, resulting in an average profit of 7367per100tonsofMSW.Theauthorsalsoinvestigatedascenariowithoutrecycling,whereonlytransesterificationwasemployed,resultinginanaverageprofitof4043. Additionally, sensitivity analysis revealed that key factors affecting profit and optimal pathways include technology yields, selling prices of products, and capital and operating costs. Notably, a 50% increase in transesterification yield led to a 62% profit boost, emphasizing the significance of technology performance. This research offers valuable insights for policymakers and waste management stakeholders, highlighting the economic and environmental benefits of sustainable MSW management and waste to energy (WtE) technologies. It demonstrates the potential for transforming MSW into a valuable resource while addressing waste-related challenges in rapidly urbanizing regions like Pakistan.

2025, Springer Nature

This paper provides a clear and concise understanding of the principles and applications of HVACR using a rigorous, yet, easy to follow presentation. The coverage is broad, including relevant support areas such as fluid mechanics, heat transfer, thermodynamics, psychrometrics, with specific applications to HVACR design and calculations, and main topics such as air conditioning processes, cooling / heating load calculations, refrigeration cycles, and HVACR equipment and systems. The book integrates and illustrates the use of data and information from ASHRAE Handbooks and Standards in step-by-step calculations of cooling and heating loads and other aspects of HVACR. Elucidation of the principles is further reinforced by examples and practice problems with detailed solutions. Firmly grounded in the fundamentals, the book maximizes readers’ capacity to take on new problems and challenges in the field of HVACR with confidence and conviction. Providing a ready reference and review of essential principles and their applications in HVACR, the book is ideal for HVACR practitioners, undergraduate engineering students, and those specializing in HVACR, as well as for practicing engineers preparing for the engineering license exams (FE and PE) in USA and abroad. The book uses both Inch-Pound (I-P) and S I systems of units to facilitate global readership and use.
Covers support areas of fluid mechanics, heat transfer, thermodynamics, and psychrometrics with HVACR applications
Covers HVACR principles and applications using many problems and solutions illustrating the use of ASHRAE Handbooks
Usage of both I P (inch-pound) and S I units to facilitate global readership and usage

2025, Anais do Seminário de Aciaria, Fundição e Metalurgia de Não-Ferrosos

sido motivo de una aplicación dinámica de nuevas tecnologías en lo que va de este siglo. La preparación de la chatarra y el uso de materiales de carga alternativos han dado lugar a la concepción de nuevos equipamientos y experiencias en todo el mundo. Surgen nuevos conceptos para el precalentamiento de la chatarra, superando las limitaciones de mantenimiento y ambientales de los conceptos iniciales y mejorando su performance energética. El aporte de energía química para la fusión supera sus límites año a año, requiriendo el desarrollo de equipamiento capaz de una acción rápida y precisa con grandes caudales de gases y sólidos inyectados. Existen nuevas herramientas para eliminar los riesgos de seguridad en la plataforma del horno, haciendo uso de sistemas de enfriamiento más seguros y duraderos, robots, automación de la operación del agujero de colado, y puertas de escoria controladas desde el púlpito. Palavras-chave: Forno eléctrico a arco; Metálicos; Precalentamiento de chatarra; Seguridad.

2024

The concept of waste biorefinery is known as one of the several energy recovery technologies capable of producing multi products in the form of biofuels and value-added products treating different fractions of municipal solid waste (MSW). The conversion technologies such as anaerobic digestion (AD), pyrolysis, transesterification, incineration treat food, plastic, meat, and lignocellulosic wastes to produce liquid, gaseous and solid biofuels. Makkah city landfills receive about 2750 tons of waste every day. Whilst during the Ramadan and Hajj seasons, these quantities become 3000 tons and 4706 tons per day respectively. More than 2.5 million animals were sold for slaughtering in 2014 Hajj, and their blood and organic solid waste were disposed untreated. Similarly, around 2.1 million plastic Zam-Zam cups were wasted every day during the 2014 Ramadan time. In the first three days of 2014's Ramadan, 5000 tons of food was wasted only in Makkah municipality. Collectively, about 3853 t...

2024, Energy

This is a repository copy of The potential of Saudi Arabian natural zeolites in energy recovery technologies.

2024

The energy consumption in Saudi Arabia has increased significantly in recent years due to a rapidly growing population and economic development. The current peak demand of electrcity is 55 GW and it is projected to become 120 GW in the year 2032. Fossil fuels are the only choice to meet the energy requirements. The government plans to double its energy generating capacity by 2020, of which around 85% will come from renewable resources. Natural zeolites are found abundantly in Saudi Arabia and have a significant role in the energy generation applications. Natural zeolites samples have been collected from the Jabal Shama occurrence near Jeddah city. All of the samples showed the standard zeolite group of alumina-silicate minerals with the presence of other elements such as Na, Mg and K etc. A highly crystalline structure is found in natural zeolites, which is critical when using in the energy applications as a process catalyst. However, there is a need of special milling and purificat...

2024

An ORC based power plant for waste heat recovery in stationary applications has been developed and experimentally characterized. The aim of the study was to investigate the performance of a sliding vane rotary expander as the device to convert the enthalpy of the working fluid, namely R236fa, into mechanical and electric energy. A theoretical model of the expander supported the design and allowed to assess the thermodynamic transformations that take place in it. Furthermore, a deep experimental campaign explored the behavior of the expander and the one of the recovery system also at off design conditions. The experimental activity on the expander included the reconstruction of the indicated diagram using a set of high frequency piezoelectric pressure transducers that provided an accurate prediction of the pressure evolution inside the cell. The overall cycle efficiency achieved was close to 8% and further improvements concerned to the expander design have been addressed. The temperature of the upper thermal source at around 120 • C and the mechanical output power close to 2 kW make the expander and the whole system suitable for plenty of potential recovery applications.

2024, Clean Energy Technologies Journal

The effect of air flowing into an in an active indirect mode solar dryer was studied. The study aimed at optimizing the airflow features of a solar dryer of active indirect feature using Response Surface Methodology (RSM). The factors of the experiment included the product slice thickness of the experimental product and the air vent of the dryer. The two factors were considered at five levels and a total of 13 experimental runs derived. The air vent was based on the following shape orientations: square, rectangular, circular, and triangular. The thickness of the product was considered at five levels of 4, 8, 12, 16 and 20 mm. The responses from the experimental set up were the air flow rate and drag force, which were determined using established equations. The optimum values for the air flow rate and drag force were 0.0275 m3/s and 0.0476N, respectively. The corresponding optimal conditions which gave the optimum responses were 100 cm2 - square inlet and product slice thickness of 2...

2024, Energy

This review highlights the current level of waste plastics valorization through thermal treatment and its potential
for African countries. Improved thermal treatment options are needed to convert the over 40% of mismanaged
waste plastics in Africa to generate electrical and chemical energy. The values of measured and calculated energy
yields from high-quality data are compared for treatment options such as pyrolysis, gasification, incineration,
catalytic and plasma gasification. The investigation revealed that, for chemical energy production, catalytic
gasification offers the best valuable product yield for single-use plastics with a promising liquid output of up to
80% with a low heating value (LHV) of 44 MJ/kg, gas output 6–7% with heating value of 48 MJ/m3, and solid
output of 10–20%. The liquid and gas products obtained at this quality could be used as fuel in a conventional
gas/diesel engine for electricity generation. For the treatment of multi-layered and composite waste plastics,
plasma gasification offers the best energy recovery approach with a potential of producing syngas with LHV of
10.8 MJ/m3 and consisting of H2 and CO weight fraction of 62.5% and 34%, respectively. The feasible waste
plastics treatment options are presented based on waste plastics profiles in selected regions of Africa.

2024

The usage and disposal of highly abundant single-use and multilayered plastics contribute to significant
ecological problems. The thermochemical recovery of these plastics to useful products and chemicals provides
opportunity for positive economic and environmental impacts. Most previous research use idealised and unrepresentative
feedstocks. To address this, various mixed waste plastics collected from the rejected fraction of a
municipal waste recovery facility in Ghana were pyrolyzed at varying temperatures of 450, 500 and 550 ◦C and
their yields compared. The obtained chemical products were analysed using several different techniques. Energy
and carbon balances of the processes were produced using the CHNS and energy content of the oil fraction and
the compositional results of the pyrolysis gas fraction, the latter of which was measured by Gas Chromatography
Thermal Conductivity Detection (GC-TCD). The oils were further assessed via Gas Chromatography Mass
Spectrometry (GC-MS) to identify the available valuable compounds. The formed oil contained approximately
40% light hydrocarbons (C6 – C11), 18% middle hydrocarbons (C11 – C16) and 42% heavy hydrocarbon
compounds (C16+). The optimal oil yield of 65.9 ± 0.5% and low heating value of 44.7 ± 0.1 MJ/kg for singleuse
plastics were recorded at highest heating temperatures of 550 and 500 ◦C, respectively. The findings provide
indication that pyrolysis is a fitting solution for energy recovery from waste plastics.

2024

Department of chemical engineering, Faculty of Chemical Technology, Kabul Polytechnic University, KabulAfghanistan... more

Department of chemical engineering, Faculty of Chemical Technology, Kabul Polytechnic University, KabulAfghanistan --------------------------------------------------------------------------***---------------------------------------------------------------------------Abstract Kabul city, the capital of Afghanistan, has experienced wide-ranging changes in spatial and socio-economic patterns during the last few years, supported by international co-operation, especially the United States and other developed and developing countries of the world. The changes have produced extensive increase in generation of municipal solid waste (MSW) and demand for electricity. Open landfilling is unfortunately the dominant method of MSW disposal in the city. This research aims to assess the value of Waste-to-Energy (WTE) facility as a solution to MSW landfill problem and to both get rid of accumulation of MSW and address energy shortage issue. Few Waste-To-Energy scenarios are developed lately: complet...

2024, Water

This Editorial presents a representative collection of 10 papers, presented in the Special Issue on Advances in Water Distribution Networks (WDNs), and frames them in the current research trends. Four topics are mainly explored: simulation and optimization modelling, topology and partitioning, water quality, and service effectiveness. As for the first topic, the following aspects are dealt with: pressure-driven formulations, algorithms for the optimal location of control valves to minimize leakage, benefits of water discharge prediction for the remote real time control (RTC) of valves, and transients generated by pumps operating as turbines (PATs). In the context of the second topic, a topological taxonomy of WDNs is presented, and partitioning methods for the creation of district metered areas (DMAs) are compared. With regards to the third topic, the vulnerability to trihalomethane is assessed, and a statistical optimization model is presented to minimise heavy metal releases. Fina...

2024

Waste to energy is internationally recognized as a powerful tool to prevent the formation of greenhouse gas emissions and to mitigate climate change. To convert municipal solid waste to energy Addis Ababa City Administration and Ethiopia Electric Power has established waste to energy plant to generate 25-MW50MW electricity per day. The Koshe-Reppie Waste to Energy plant has been constructed on the area of 7-hectares from the total area of 37-hectares of dumping site. The Facility is being operational the likely sources of negative and positive impacts from the waste to energy plant are leachate from storage and handling of municipal solid waste; unusable wastes for disposal; wastewater from the plant's energy generation process and from bathrooms; air emissions from the spent exhaust gases; noise emissions from the operation of the plant; and bio-char and residual ashes for management further use or disposal. The composition of waste which is delivered to WTE facility is crucial...

2024

Plastic waste has many complex chemical components. In developing countries, direct incineration is often used to reduce plastic waste, releasing pollutants into the atmosphere. A more environmentally sound alternative is pyrolysis. It can turn plastic waste into an alternative fuel. A catalyst, such as natural zeolite, can reduce the energy used in pyrolysis. However, mineral contaminants must be removed first to get optimum activity. This research was focused on using Ende natural zeolite as a catalyst, determining the properties of the mineral in its activated form. It also investigated the interaction between H-zeolite composition and the operating temperature towards pyrolysis oil yield. The experimental results showed that Ende natural zeolite contained a mixture of mordenite, clinoptilolite, and quartz. After activation and modification, there was an increase in the surface area from 53.17-104.67 m 2 /g. The average pore radius ranged from 19.96-34.21 Å. There was an increase in the pore volume from 22.01-72.34 cc/g. The total acidity changed from 1.456-5.342 NH 3 /g. The optimum catalyst concentration was 10% in the pyrolysis of 1000 grams of plastic waste catalyzed by 100 grams of H-zeolite. The oil yield decreased at 15% concentration. The 10% concentration worked best at 400 ℃.

2024, Honours Thesis, Federation University Australia

Pressure reduction systems are implemented in pharmaceutical and food industry factories worldwide, and currently the majority will bleed off any excess steam pressure from the reduction stations responsible for providing steam pressure to processes in the facility. This steam pressure is bled off into the atmosphere, with all of its useful energy being entirely wasted. This project aims to investigate the viability of an expander technology in these facilities in order to utilise this wasted steam pressure to create onsite energy. The viability of such a technology is investigated through creating a mathematical model of such a system, that has the ability to analyse the system dynamically and statically, in order to yield results on the power output of such a system for a range of given inlet steam pressures. Simulations are ran using this model with the results logged and plotted in the figures and tables in this paper. From doing this, it was concluded that significantly higher inlet pressures led to an increase in power produced from the expander. The effect of changing the inlet fluid mass flow rate and pressure, had on the system, was seen to cause instabilities on the density of the fluid in the pressure vessel. By implementing a large pressure vessel between the expander and main steam pressure pipe, it can act as a damper in the system, increasing the stability. However, slight instability in the system was concluded to be advantageous as extra energy was restored by the system. This allows the expander to create extra power for a given inlet pressure, as for a short time period the system has an increase in the energy available. This unique characteristic of the system, was due to the onsite boiler or compressor supplying the main pipe with a fresh supply of pressurised steam as the processes downstream used the available energy, thus causing a pressure spike at the inlet of the main pipe. With these findings, it was deemed viable that such a technology could be implemented immediately into facilities with significant monetary and environmental benefits ensuing.

2024, Energy Conversion and Management

The paper analyzes some of the problems connected with the design, construction and management of cogeneration plants for district heating networks (CHP-DHN). Although the advantages of cogeneration systems compared with conventional ones for separate energy production, one of the unresolved problems is that of the variability of operating conditions, can often render the application of these solutions ineffective. In particular, the aim of this study is to propose a multi-objective optimization methodology that tries to take into account both energy and economic aspects. After an analysis of the current scenario, the application and use of CHP plants in the international context and the main technological features, followed by the identification of incentive systems that have allowed or limited the spread, attempts are made to define a design methodology based on a multi-level optimum design based approach for increasing the operation share of CHP. The methodology starts from a general system vision, up to detailed aspects such as the management of a CHP-DHN system, taking into account the multiplicity of variables and constraints involved. This methodology has been applied to two case studies representative of the different applications, to verify its robustness and analyze the possible results obtainable. In particular, a general case was taken into consideration, in which a first level design was performed by analyzing various possible system configurations and evaluating their goodness through the tools provided by the aforementioned multi-objective methodology. Then the methodology has been applied to an intermediate level, taking into consideration an existing CHP-DHN plant and going to evaluate the performance considering possible modification of the operation. The results obtained confirm that a combined energetic and economic approach to design allows to obtain an economically feasible system, but at the same time avoids incurring over-sizing, under-sizing or functioning phenomena far from the concept of energy efficiency, difference of what happens for many plants today in operation. Furthermore, through a simple variation of the modularity of the plant, significant benefits can be obtained.

2024, Solid Waste Engineering and Management

Wang, LK, Wang, MHS, Hung, YT (editors), Aziz, HA (consulting editor) (2022). Solid Waste Engineering and Management, Volume 3, Springer Nature Switzerland, 627 pages. https://doi.org/10.1007/978-3-030-96989-9 ..... ABSTRACT: This book is the third volume in a three-volume set on Solid Waste Engineering and Management. It focuses on tourism industry waste, rubber tire recycling, electrical and electronic wastes, health-care waste, landfill leachate, bioreactor landfill, energy recovery, innovative composting, biodrying, and health and safety considerations pertaining to solid waste management.. The volumes comprehensively discuss various contemporary issues associated with solid waste pollution management, impacts on the environmental and vulnerable human populations, and solutions to these problems. .... KEYWORDS: Waste management in the tourism, Rubber recycling, Electrical waste disposal, Clinical waste management, Energy recovery, Dredging, Biodrying, Radioactive waste

2024

Resumo Em função das condições desejadas no processamento do aço no Forno Elétrico a Arco (FEA), a escória final tem teor elevado de FeO, contém fósforo e pode ter, ainda, alto teor de alumina. Para controlar o consumo de desoxidantes, formar uma escória adequada no forno panela (FP) e evitar a reversão de fósforo, é importante minimizar a passagem da escória do FEA para a panela, no vazamento. Assim, é essencial conhecer a quantidade de escória passante para o controle e previsão adequados do processamento no FP. Neste trabalho é apresentada uma metodologia para, através de um balanço de massa levando em conta medidas de composição realizadas durante o processo, determinar a quantidade de escória passante e o volume de escória no final do processamento no FP. É empregado um método numérico simples e demonstra-se que os resultados obtidos são suficientemente adequados para melhor conhecimento e controle do processo por parte do engenheiro responsável, possibilitando gerar informações precisas para cálculos de correções (exemplo: formulação de uma nova escória sintética, correção de desgaste de refratários, ajuste de basicidade, etc.). Palavras-chave: Forno elétrico; Escória; Balanço de massa; Refino secundário.

2024, Anais do Seminário de Aciaria, Fundição e Metalurgia de Não-Ferrosos

2024, Shanghai Ligong Daxue xuebao

Global warming is nowadays one of the main and important issues. As the increase in the concentration of carbon dioxide and other greenhouse gases in the atmosphere as a result of the combustion of these gases causes such phenomena. Therefore, oil and gas plants need to be constantly reviewed over time to maintain high performance and operability, especially while changing feed composition and rate to meet standard product specifications. The aim of this study is to study the effect of flare gases recovery using gas compressors on the economic and environmental performance of an existing oilfield plant. A commercial simulation program aspen HYSYS Version 11 was used. The Kalabsha Central Processing Facility (KCPF) in the Western Desert of Egypt is the studied plant. This plant handles 30 million standard cubic feet per day (MMSCFD) from free water knock out drum and 1.6 MMSCFD of gases from heaters. 20 MMSCFD from gas is charged to the gas pipeline and 10 MMSCFD is sent to the flare with the 1.6 MMSCFD. It is proposed to install gas compressors to capture the gases from the free water knock out drum and heaters before sending them to the flare. Such technology can be used as a guide in upgrading existing and new oil and gas plants to reduce gas flaring. In addition, environmental protection also adds more economic profits from burning the recovered gas besides increasing the life of the flare equipment.

2024, Fuel Communications

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2024, 2023 International Conference on Networking, Electrical Engineering, Computer Science, and Technology (IConNECT)

A solar thermal-to-electricity conversion system that optimizes the temperature difference between hot and cold sources has been designed using Peltier thermoelectric. The system consists of three main components, namely the heating system, cooler, and drive to position the prototype following the direction of motion of the sun. With a greenhouse effect concept, the heating system at the top keeps the temperature in the acrylic room warm. The hot side of the Peltier is placed with an aluminum plate and andesite stone as heat conductors and storage. The cooling system uses a metal-wrapped fluid as a source of cold temperature equipped with temperaturereducing aluminum foil and nitrogen gas to keep the fluid at a low temperature. Finally, the drive system uses a hydraulic to move the design module following the direction of motion of the sun, whose light will be focused by a convex lens to concentrate. The Peltier is assembled in series and step-up to increase the output voltage to produce maximum results. This prototype design can hopefully contribute to the development of renewable energy.

2024, Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

The exhaust manifold is the bridge connecting the cylinder head to the catalytic converter, which collects the exhaust gases from the multiple cylinders and sends them to one pipe exhaust. The temperature of the exhaust gases in the manifold reaches so high as 800 °C. So, the exhaust manifold is affected by thermal loading due to the high-temperature gradient. This paper presents a numerical and experimental analysis implemented a typical cast iron exhaust manifold. In this study, the temperature extracted from the manifold done by employing different shape types of longitudinal fin mounted on the external surface of the manifold. In the numerical analysis, the model generated by Solidworks software firstly and simulated using ANSYS Workbench R19 for different cases. The experimental work adopted two best numerical modelling results, which have been selected for fabrication and testing experimentally. Results found that the effect of fin installation gives a better reduction in the surface temperature along the exhaust manifold, especially in the high thermal loaded middle section, where the temperature drops to more than 100 ℃. Also, the Sinusoidal fin model achieved slightly better results than the straight model despite the small surface area. Moreover, the comparison between the numerical and experimental works gives a good matching reached 1.8%, which is assisting the numerical analysis.

2024, Waste Plastic to Fuel Conversion

The personal and commercial use of plastics has increased considerably in the past few decades and, considering their non-biodegradable nature, underlines an increasing need to sustainably and effectively manage waste plastics. Pyrolysis is a fairly novel approach in plastic waste management, with only a few decades’ worth of research and implementation, but potentially significant implications to waste management and energy creation due to the procedure’s capacity to degrade polymer plastics into pyrolytic oil, which is a fuel-substitute. This study implemented an experimental proof-of-concept to utilize pyrolysis in a controlled, sustainable, and fairly inexpensive setting to recover liquid fuel. With particular emphasis on the viability and sustainability of pyrolysis as a plastic waste management approach, this research study sought to determine the optimal and reliable operational conditions of thermal pyrolysis for potential future scalability and commercialization of the model. Locally-fabricated and repurposed materials were utilized to design and build a pyrolytic reactor in a homestead setting, and high-density polyethylene (HDPE) plastics were used as the feedstock. The results corroborated the waste-to-energy potential of pyrolysis, with the resulting pyrolytic oil being refined into practically-applicable gasoline and diesel fuel products used in low-combustion, non-automotive engines. The pyrolysis project highlights the potential social, environmental, and economic impact of pyrolysis, especially in the context of a developing country like the study setting of Kenya.

2024, IOP Conference Series: Earth and Environmental Science

Natural zeolite is one of prospective material with various applications. The material has low-cost provisioning and abundant availability in the world. Mordeniteclinoptilolite is one of the common types of natural zeolite; one of the deposits are located in Gunungkidul, Yogyakarta, Indonesia. For optimizing the utilization, some treatment is needed, calcination being one of the possible treatments. The dealuminated natural zeolite was used as the base material for understanding the transformation effect, then calcinated the zeolite in various temperature range between 400 °C and 1000 °C. Some characterization was conducted after the treatment, such as XRD, SEM-EDX, and BET to explore the structure, morphology, composition, and specific surface area. Drastic structure changes were demonstrated at the calcination of 1000 °C which eliminating the zeolite structure into cristobalite as one of the silica structures. The specific surface area decreased after 600 °C, even elapsed after the structure change. Calcination has the ability to transform the zeolite structures and also affected the specific surface area properties. This transformation provides critical information for further application of natural zeolite in the various treatment of calcination.

2024, Journal of Scientific & Industrial Research

Refineries Residual Fuel Oil (RFO) and Bakelite (BL) and were co-pyrolyzed together using catalyst ZSM-5 under the atmospheric pressure with different mixing ratios of the feedstocks. The TGA analysis shows that most of the degradation take place between the temperature range of 250-400 o C. The studies were carried out at two different temperatures of 500 o C and 600 o C using a batch reactor with different blended ratios, with blended feedstocks to catalyst ratio of 4:1. The effects of the two variables i.e. temperature and blending ratios among the two feedstocks, in terms of the products yield of liquid fuel, gas, coke and conversion were determined. The blending ratio of 4:1 (RFO: BL) yielding highest conversion of 76 wt. % at 600 o C was found to be the most favourable condition in this investigation.

2024, TECNICA ITALIANA-Italian Journal of Engineering Science

The new F1 direct-injection turbocompound engines V6 of 1600cc have innovative systems for the recovery of the wasted energy. Fuel and airflow to the engine are limited as well as the amount of fuel and electric energy from the battery available for the race. It is therefore vital to implement the most efficient strategy to improve powerplant efficiency. It is also important to handle with exceptional situations as the necessity to obtain a best lap or to reach and pass other cars. The following article introduces strategies for the electronic engine management systems to deal with this hybrid powerplant. In this paper the shaft speed vs time pattern determines how the powerplant energy system is managed and maximizes a parameter in the various situations. Four critical conditions are analyzed: start, braking, fast and slow curve. The launch (start) maximizes the average acceleration of the car, adjusting it to the maximum traction force available from the powerplant and tires. The braking maximizes the braking distance and the energy recovery. The fast curve strategy maximizes the speed out of the curve and minimizes the time. The slow curve strategy maximizes the energy recovery and the speed out of the curve.

2024, Fuel Communications

2024, International Journal of Ecosystems and Ecology Science (IJEES)

The purpose of this study is to measurably assess an integrated industrial biogas plant and introduce some biogas technologies as alternative sources for energy production in the Kingdom of Saudi Arabia. Biodegradable materials such as organic wastes, sewage, municipal wastes, and green wastes are very important precursors used in energy production plants for obtaining biogas and some certain organic fertilizers. Biogas plants have many benefits; one of their primary functions is being used as anaerobic digesters with different configurations to treat animal and agricultural wastes for energy production. During the process, microorganisms convert biomass wastes into biogas, mainly methane and carbon dioxide. The study shows four steps carried out of a full-scale biogas plant for a life cycle analysis (LCA) with 950 kWh as: initially, the scope and target were defined, then inventory was analysed, the impact was assessed, and finally the results were interpreted in detail. The results of analysis showed that the biogas plant can preclude the equivalent of 2.43E+09 kg of CO2 global warming and the ozone depletion of 18.80593 kg of CFC-11 equivalent. It was also determined that aquatic environment eutrophication contributed to the prevention of toxicity, acidification, and eco-toxicity for humans. Some organic by-products were obtained from anaerobic digestion (AD) and used as fertilizer for agricultural or other productions.

2024, Journal of Cleaner Production

Municipal solid waste generation is a rapidly increasing challenge that is leading to severe pollution and environmental degradation in many urban areas of developing countries. Globally, the solid waste sector accounts for 18% of methane emissions and 3-4 % of greenhouse gas emissions overall. Waste handling and disposal systems in most large cities have largely been designed with minimal accounting of environmental issues. This study presents the Waste to Energy Recovery Assessment (WERA) framework, a new quantitative decision support model for initial evaluation and alternative comparisons of different thermochemical treatments of municipal wastes. The framework not only accounts for benefits through electricity generation but also accounts for emissions from facilities and the associated social cost of carbon in a cost-benefit assessment. The assessments are conducted with Monte Carlo simulations that explicitly account for uncertain factors such as future composition and generation of solid waste, technical efficiency of treatment processes, capital and operating costs, as well as future policies. The framework is used to study waste-to-energy (WtE) systems for Abu Dhabi, Riyadh, Tokyo and New York. The results show that WtE systems can fulfill only 1.4-3.6% of 2014 electricity demand in the analyzed cases. Furthermore, the net present value for different technologies can be positive if collection fees and electricity rates (potentially set through feed-in-tariff policies) are sufficiently high. The analysis for Abu Dhabi and Riyadh also reveals that in a limited set of conditions (of technology efficiencies, and waste collection rates etc.) the WtE facilities can be self-sustaining investments.

2024, Technium: Romanian Journal of Applied Sciences and Technology

Polypropylene is converted into bio-oil through catalytic pyrolysis using dolomite as a catalyst. The purpose of this study was to determine the effect of using dolomite directly without prior treatment on the bio-oil produced from the pyrolysis of propylene plastic. The amount of loading catalyst used is 5%. Increasing the pyrolysis temperature from 350 to 450 ℃ increased bio-oil from 35.56 wt% to 64.84 wt% by reducing gas to 21.08 wt%. In thermal pyrolysis, the production of bio-oil is 85 wt% with 19.30 wt% char. In the GC-MS analysis of bio-oil from thermal and catalystic pyrolysis, the most dominant alcohol composition was obtained. Based on the result of the analysis, it can be concluded that the bio-oil obtained can be further developed into fuel.

2024, Nature Environment and Pollution Technology

Organic junk contamination is one of the serious environmental concerns throughout today’s world. Heavy usage of throwaway plastics devastates nature by obstructing rainwater drainage. From constant exposure to sunlight and warmth, plastics release hazardous gasses into the atmosphere. To reflect the vastly increased amount of various waste plastics, a scaled hybrid plasma gasification reactor is being introduced, which uses an advanced pyrolysis process to break down the plastic waste. The design is simple, transportable, easy to handle, and required very little repair work on long-period usage. Thermochemical investigations are carried out at temperatures ranging from 400 to 600 degrees Celsius, with heating rates ranging from 15 to 22 degrees Celsius per minute, yielding 76-88 percent pyrolysis oil, 10-23 percent syngas, and 4-15 percent chars as besides. It occurs when the molecular architecture of polymers is separated, resulting in the creation of Synthesis gas, which is then ...

2024

This paper provides a critical and analytical assay in the process vicinity of an Organic Rankine Cycle (ORC) resulting in a representation of a flow model as the best approach to implement an efficient Plant focusing on the robust and elegant energy production. There have been so many predictive and sensing process models presented for a gist and substantial control of the ORC plant in recent years but the proposed Model provides the robustness by performing all the roles in increments; e.g. in the insertion of efficient working fluid, analyzing turbine’s output power, boilers efficiency and the rate of mass flow. The proposed model optimizes the performance of ORC by response simulating outputs under certain conditions which relegates the errors and sudden disturbance in the process flow. The selection criterion has been made by considering the temperature profile of northern areas in Pakistan. This study will be elaborating efficient model design and implementation to conjure up ...

2024, Chemical engineering transactions

Unsustainable consumption and production patterns, together with industrialization and population growth, have increased the generation of municipal solid waste (MSW), causing several environmental problems. The European Waste Framework Directive (WFD) sets waste prevention, preparation for reuse and recycling as priority strategies. Nevertheless, still a great amount of MSW ends up in landfills and waste-to-energy (WtE) plants. WtE plants reduces waste volume and allows efficient recovery of energy, however, incineration results in various types of solid wastes, bottom, boiler and fly ashes (FA). Due to the concentration of dangerous substances, FA are treated by means of stabilisation/solidification (S/S), thermal treatments or combined treatments, to reduce their toxicity and to avoid negative impacts on the environment and human health. Among S/S alternatives, stabilisation with cement and carbonation are one of the most popular. To determine the environmental performance of the...

2024, Journal of Food Science and Engineering

Cassava regarded as a white gold of Africa is driving the agricultural commercialization and industrialization with small to medium technologies in Uganda. There is an overwhelming demand for high quality cassava flour (HQCF) by Bakeries, beverage industry, paper board and composite end markets. The end market for HQCF dictates on its quality attributes and rewards for its quality in terms of price offered within their minimum standards. However, obtaining sustainable amounts of HQCF for these markets calls for devoted efforts. Limited types of HQCF processing technologies exist and if they exist, their efficiency, costs and sustainability are not well understood. We evaluated high quality cassava drying technologies in Northern and Eastern Uganda in two years using naturally ventilated wooden screen solar drying structures and open air sun drying structures. Naturally ventilated wooden screen solar dryers produced clean dry high quality cassava chips free off insect and bird contamination and caused faster drying to less than 14.3% MC in 1.5 hours than open outside drying conditions. We recommend naturally ventilated wooden screen solar dryers for small and medium cassava processors during dry and rainy season. Half tone to one tone cassava chips dryers per day drying unit can cost one 2,258-4,338 USD to make it functional. Also open outside raised metallic racks with black surface can give good results on a good sunny day especially for starters on small scale basis. A small durable unit of 150 kilograms per day can be made with 500 USD.

2024, Waste Management

Olive mill wastewater sludge (OMWS) and waste tires (WTs), abundant wastes in Tunisia, were used as feedstock in a slow co-pyrolysis pilot reactor to produce upgraded pyrolytic oil as an alternative fuel. Despite the improvement of some properties of the pyrolytic oil when waste tires were added in the feed blend, a negative synergy was observed in the yield of the oil compared with that of char. The characterization of oil samples showed synergetic interaction between OMWS and WTs during co-pyrolysis which led to a partial deoxygenation and resulted in reduction of viscosity and increase in the calorific value of the co-pyrolytic oils. However, the co-pyrolytic oil properties did not meet the requirements of commercial diesel and will need further improvement by effective standardization to meet marketable specifications. Compared with catalytic fast pyrolysis (CFP) followed by hydrodeoxygenation (HDO), OMWS/WTs slow co-pyrolysis showed some limitations but it can be considered as a simple, clean and cheap process upgrading technique for bio-oil production ($40% lower in fixed capital investment and $30% lower in fuel selling price).

2024, Proceedings of the International Conference on Sustainable Biomass (ICSB 2019)

Thermal degradation at 500 o C to a Real Municipal Solid Waste (RMSW) has leave a footprint of problem with very low mass yields of liquid fuel. Therefore, in the presence research, it has been attempted to increase the mass yield of liquid fuel by using Long Catalyzer Downstream (LCD) equipped with top and bottom outlet in stage pyrolysis. Two types of natural catalysts (zeolite and kaolin) that have been activated at 500 o C for 2 hours were used in this experiment. Also, LCD temperatures were varied from 200-300 o C with pyrolizer temperature were hold at 500 o C. The experimental results revealed that there was a significant increase in the mass yield of liquid fuels compared to pyrolysis without catalysts and direct catalyst of pyrolysis. The presence of LCD was making a major contribution to generate secondary cracking and producing more products of short hydrocarbon ranges from MSW feedstock. Among natural zeolite and kaolin catalysts, natural zeolite catalysts have productivity behavior better than natural kaolin. The higher mass yields in liquid fuels have been demonstrated by natural zeolite catalysts.

2024, Case Studies in Thermal Engineering

Municipal solid waste (MSW), disposed of at open dumping sites, poses health risks, contaminates surface water, and releases greenhouse gasses such as methane. However, pyrolysis offers the opportunity to convert MSW into Bio-Oil (BO) for clean energy resource. In this paper, an MSW sample consisting of plastic, paper and cardboard, rubber and textiles, and vegetable waste is pyrolysed on a laboratory scale in a fixed-bed vacuum reactor. In the non-isothermal process, the sample was fed into the reactor and then heated. In the isothermal process, the reactor is first heated and then the sample is added. The non-isothermal process created greater BO in both quality and quantity. The BO had a larger amount of gasoline species than diesel-48 fuel, with at 33.44%the BO produced by isothermal pyrolysis and 36.42% in non-isothermal pyrolysis. However the product of isothermal pyrolysis had a higher acid content that reduced its heating value.