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To limit global warming and meet international environmental targets, more environmentally benign technologies must be used in the residential market. Combined Heat and Power (CHP) at the micro-scale (<50 kWe) is seen as one of the best solutions that offers simultaneous generation of both electricity and heat with high overall efficiencies using environmentally friendly fuels (e.g., biofuel, hydrogen, syngas). In this study, four major micro-CHP prime movers (i.e. Micro-gas turbine, Gas engine, Stirling engine, and Fuel cell) have been evaluated in terms of their performance and the currently available technologies and products. The most suitable options for household applications were identified using Political, Economic, Social, Technological, Legal, and Environmental (PESTLE) risk analysis and a Multi-Criteria Decision Analysis (MCDA). Fuel cells display the best environmentally friendly properties despite their price and high start-up time. Gas engines (Reciprocating engines) have the most developed technology with the fastest start-up time and high efficiencies but have vibration and noise issues. Micro-gas turbine micro-CHPs are emerging into the market with relatively cheaper prices, lower maintenance, and good start-up time. Stirling engines are fuel flexible with reasonable prices and available products. Micro-CHP systems, particularly when running on biofuels and hydrogen, provide excellent energy solutions for the future net zero buildings. [ABSTRACT FROM AUTHOR]

Global energy market price volatility and an upward trajectory of prices per unit of electricity have sent all industrial sectors and many economies to the brink of recession. Alongside the urgent need for decarbonisation of all industries, achieving a globally higher level of energy independence across all sectors seems imperative. A multi-disciplinary approach with a proposed system of CO2 emissions reduction and capture technologies has the potential for short-term emissions reduction to near-zero in the steel industry—although some of the mechanisms can be implemented across most heavy industries. The findings of this research show a CO2 emissions reduction of ~30% from 977 t of CO2 to 684 t in one single blast furnace production cycle (based on 330 tonnes of liquid iron production capacity, with the mean of 2.1–3.2 tonnes CO2/t of steel and chemical reactions emissions applied), by switching the electricity provider for operating the electric heaters to providers generating energy exclusively from renewable sources. Replacing coal with biomass and adding post-combustion capture units to the blast furnace operation, will add carbon neutrality into the process—resulting in CO2 emissions reduction to near-zero. Carbon capture from biomass utilisation (BECCS) will add the benefit of carbon-negative emissions to the cycle. Simultaneously, energy-saving and process improvement measures implementation (up to 60% efficiency increase), excess heat recovery <30% of energy savings, and retrofitting renewable energy technology resulted in an energy independence of 88%. Engineering solutions, partly subsidised in the UK, are readily available for implementation in the iron and steel manufacturing industry. [ABSTRACT FROM AUTHOR]

The requirement to monitor and control industrial processes has increased over recent years, therefore innovative techniques are required to meet the demand for alternative methods of particulate measurement. Resonant mass sensors are now strong candidates for accurate mass measurement and are frequently used in many diverse fields of science and engineering. This paper presents the design, modelling, and optimal geometry selection for sensitivity improvement of a U-shaped glass tube as a resonant mass sensing cantilever with a view to becoming a component of particulate measurement equipment. Finite Element Analysis (FEA) was used to develop the system which was validated experimentally using a physical model. This paper focuses on both the proof of concept and the geometry selection of the sensor using analysis of the system sensitivity for best selection. Modal and harmonic analysis were undertaken across a range of commercially available glass tube sizes from 6 mm to 10 mm diameter, to determine the optimal geometry selection, validated with practical experimental data. Results show a consistent difference of 3–5% between the simulation and experimental results, showing strong correlation. This research provides a methodology on the development of using a U-shaped glass tube for accurate mass measurement with a view to exploring the design as a component of particulate emissions equipment. The experimental and simulation results confirm that the highest sensitivity is achieved when the geometry dimensions, and therefore the vacant mass of the tube, is reduced. The 6 mm diameter tube with the smallest bend radius was the most suitable design to meet the design criteria. The calibration curve was plotted to allow an unknown mass to be calculated, which gave an R2 value of 0.9984. All experimental work was repeated three times with results giving an average of 0.44% between the minimum and maximum showing strong linearity and suggesting the potential for implementation of the methodology in its intended application. The design provides possible solutions to some of the issues currently seen with particulate measurement from stationary sources. [ABSTRACT FROM AUTHOR]

The requirement to monitor and control particulate emissions from industrial processes using continuous emission monitoring systems (CEMS) has significantly increased over recent years. Under current legislation, CEMS equipment requires calibration against the standard reference method (SRM) using isokinetic sampling and gravimetric analysis under controlled conditions as detailed through BS EN 13284-1 "Stationary source emissions–Determination of low range mass concentration of dust. Manual gravimetric method". This process includes pumping a known volume of gas through a filter, which is weighed before and after sampling, and the total mass of dust per m3 can then be calculated to output results in mg/m3. As tougher legislation is introduced and stringent emission limit values (ELVs) are imposed on emissions processes in the United Kingdom (UK), the calibration of CEMS is increasingly more difficult due to the reliability of the SRM at low concentrations. The accuracy of results from the SRM and therefore CEMS equipment must be questioned when the uncertainty of measurement is higher than process ELVs. This research analyses data taken from an industrial survey and 21 UK processes where the standard reference method, in accordance with the procedure in BS EN 13284-1 has been used for particulate measurement. Investigating the reliability of isokinetic sampling when used as a method to extract a representative sample from a stack process when used in conjunction with innovative, alternative methods of sample analysis. In processes with particulate emissions <5 mg/m3, 80.7% of the total sample was collected in the rinse, and for processes >5 mg/m3, 56.4% of the sample was collected in the rinse. The data does not suggest any correlation between any of the measured parameters and the percentage of particulate in the rinse, including the stack velocity, isokinetic percentage, sample volume, and total mass concentration. [ABSTRACT FROM AUTHOR]

• A new 12 kWe microturbine combustor is designed for biogas fuel. • The experimental analysis of the combustor was carried out at different operating points. • The combustor was modeled, and the model validated against experimental data. • The model was used for in depth analysis of the combustor (emissions and reactions). Nowadays, the design and application of free-carbon emission renewable fuels in micropower generators seem to be interesting to provide decentralized clean, affordable, and resilient energy in developing countries, thereby reaching the 2050 net-zero carbon emission objectives. The operation of micro-scale Closed Cycle Gas Turbine (CCGT) system with these fuels such as biogas without negatively impacting the combustion and micro-turbine performance, should be managed and controlled in the successful design of a micro gas turbine combustor. The application of biogas as a potential fuel due to its low calorific value and impurities, should be made possible in an efficient micro gas turbine combustor design for maintaining NOx emissions, the combustor's ability to light and to tolerate sudden changes in engine load, efficient combustion throughout the engine cycle, and the achievement of the required life. In this work, the efficient design techniques and operation of the 12 [kW] biogas micro-turbine combustor are analyzed and investigated. The designed combustor was manufactured, tested and modeled. Afterward, the emission potential of the designed combustor is discussed and how properly a design scenario for a new fuel should be responded. [ABSTRACT FROM AUTHOR]