Exergy analysis and efficiency evaluation for an aluminium melting furnace in a die casting plant

An aluminium melting furnace efficiency in a die casting plant was investigated using energy and exergy methods. Energy efficiency and exergy efficiency values were evaluated for the natural gas-fired furnace, and the efficiency improvement was analyzed before and after two new regenerative burners were installed on the furnace. The research analyzed and compared the environmental impacts attributable to the melting furnace before and after the burner upgrading project, and also provided a financial analysis of the capital investment of the upgrading project. The study shows that the exergy method can be used beneficially to analyze the furnace efficiency and that exergy efficiency is a more practical measure in reality. Thus, it is believed that further applications of exergy methods are desirable to a wider range of industrial and engineering applications. From the results of comparisons, the study shows that the regenerative burner technology and stage-combustion technique can improve combustion performance, reduce fuel (natural gas) consumption and lower NOx and Co2 emissions. Adopting the regenerative burner and stage-combustion technique will be beneficial to the die casting plant on energy saving and cost reduction. Recommendations are also made for further efficiency improvements.

Exergy analysis and efficiency evaluation for an aluminium melting furnace in a die casting plant

An aluminium melting furnace efficiency in a die casting plant was investigated using energy and exergy methods. Energy efficiency and exergy efficiency values were evaluated for the natural gas-fired furnace, and the efficiency improvement was analyzed before and after two new regenerative burners were installed on the furnace. The research analyzed and compared the environmental impacts attributable to the melting furnace before and after the burner upgrading project, and also provided a financial analysis of the capital investment of the upgrading project. The study shows that the exergy method can be used beneficially to analyze the furnace efficiency and that exergy efficiency is a more practical measure in reality. Thus, it is believed that further applications of exergy methods are desirable to a wider range of industrial and engineering applications. From the results of comparisons, the study shows that the regenerative burner technology and stage-combustion technique can improve combustion performance, reduce fuel (natural gas) consumption and lower NOx and Co2 emissions. Adopting the regenerative burner and stage-combustion technique will be beneficial to the die casting plant on energy saving and cost reduction. Recommendations are also made for further efficiency improvements.

Automated Residential Energy Audits Using a Smart WiFi Thermostat-Enabled Data Mining Approach

Smart WiFi thermostats, when they first reached the market, were touted as a means for achieving substantial heating and cooling energy cost savings. These savings did not materialize until additional features, such as geofencing, were added. Today, average savings from these thermostats of 10–12% in heating and 15% in cooling for a single-family residence have been reported. This research aims to demonstrate additional potential benefit of these thermostats, namely as a potential instrument for conducting virtual energy audits on residences. In this study, archived smart WiFi thermostat measured temperature data in the form of a power spectrum, corresponding historical weather and energy consumption data, building geometry characteristics, and occupancy data were integrated in order to train a machine learning model to predict attic and wall R-Values, furnace efficiency, and air conditioning seasonal energy efficiency ratio (SEER), all of which were known for all residences in this study. The developed model was validated on residences not used for model development. Validation R-squared values of 0.9408, 0.9421, 0.9536, and 0.9053 for predicting attic and wall R-values, furnace efficiency, and AC SEER, respectively, were realized. This research demonstrates promise for low-cost data-based energy auditing of residences reliant upon smart WiFi thermostats.

Experimental Study and Design of Biomass Co-Firing in a Full-Scale Coal-Fired Furnace with Storage Pulverizing System

Co-firing coal and biomass in existing power plants facilitates influential advancement in the use of renewable energy resources and carbon emissions reduction. Biomass is intended as a CO2-zero net emission because, during its rise, it uses the same fraction of CO2 from the air as that released during its combustion. In addition, the content of nitrogen and sulfur in biomass is lower than in coal. Therefore, the emissions of NOx and SOx can be minimized by co-firing it with coal. In general, the effect of biomass direct co-firing on safety, pulverizing system performance, furnace efficiency, and NOx emission in full-scale furnaces is rarely studied. In this study, biomass direct co-firing was carried out in a 55 MW tangentially fired pulverized coal furnace. The effects of biomass co-firing on safety, the performance of the pulverizing system, furnace efficiency, and pollutant emissions (unburned carbon and NOx) are studied. The results show that the blending of biomass fuel with less than 20% of coal has no issue with respect to auto-ignition and safety. The performance of the pulverizing system is affected up to a certain limit due to the difficulty of grinding the biomass particles into required fineness. The biomass co-firing up to 20% is feasible, but greater than this percentage will severely affect the furnace efficiency. The co-firing of biomass enhanced the NOx reduction significantly and further improved the performance of the SNCR process. This study could provide guidance for the application of biomass co-firing in industrial furnaces.

Simulation of effective lime burning in a shaft furnace

Increasing of fuel and energy usage efficiency is an actual task. Technology solutions on excessive furnace gases heat utilization considered. A mathematical model of heat transfer in a shaft furnace calculation quoted as well as results of calculated estimation of shaft furnace heat operation while producing lime. Analysis of methods of such a furnace efficiency increasing presented, including recuperation for combustion air warming-up, furnace off-gases recirculation and modification of the furnace shell structure.