The new meaning of solid fuels from lignocellulosic biomass used in low-emission automatic pellet boilers

The energy obtained from biomass in the global balance of energy carriers is the largest source among all RES. It should be borne in mind that the share of biomass as an energy carrier in the total balance is as much as 14%. The basic sources of renewable energy used in Poland are the wind power industry and biomass. Organic chemical compounds are the source of chemical energy for biomass. The biomass can be used in a solid form (wood, straw) or after being converted to liquid (alcohol, bio-oil) or gas (biogas) form. Pellets, meaning, the type of fuel of natural origin created from biomass compressed under high pressure without the participation of any chemical adhesive substances are recognized as the most woodchips are the most popular type of pellets on the market. Fuel created in the form of granules is very dense and can be manufactured with low humidity content, which translates into an exceptionally high burn efficiency. The authors of this article burned agro pellets from Miscanthus giganteus without additives and with solid catalyst and conducted a series of tests that determine the impact of boiler settings (blast power, time of feeding, chimney draft) on the process of burning fuel in real conditions. A solid catalyst was used to improve combustion conditions in one of the fuels. The catalyst burns carbon monoxide and reduces nitrogen oxides. The results in the form of observation of selected parameters are summarized in the table

The quality of wood pellets used in automatic class 5 Ecodesign boilers on the retail market in the context of air protection in Poland

Wood pellets, commonly referred to as biomass fuel, are increasingly used in heating and district heating in the European Union countries, including Poland. Their use in class 5 and/or Ecodesign boilers enables an individual consumer to use energy from renewable sources, reduce the environmental burden by reducing the emission of harmful compounds, and provides a sense of comfort by automating the boiler system. The article presents the current situation in the global wood pellet market, describes the basic quality standards applicable to this fuel during production, and indicates the difficulties in the implementation of programs co-financing the replacement of obsolete coal-fired boilers with automatic class 5 biomass-fired boilers. The research presented in this article is focused on the presence of contaminants in the DIN Plus, EN Plus, and A1 pellets, as well as in non-certified pellets. The analysis has shown that the use of wood pellets containing prohibited substances negatively affects boiler operation and contributes to the formation of slag and the emission of harmful compounds, making the discussed fuel non-ecological. Pellet drzewny, potocznie nazywany biomasą, staje się coraz bardziej dostępnym paliwem stosowanym w ogrzewnictwie i ciepłownictwie w krajach Unii Europejskiej, jak również w Polsce. Jego zastosowanie w kotłach grzewczych posiadających 5. klasę lub/i świadectwo Ecodesign umożliwia indywidualnemu konsumentowi wykorzystanie energii pochodzącej ze źródeł odnawialnych, zmniejszenie uciążliwości dla środowiska poprzez redukcję emisji szkodliwych związków do powietrza oraz zapewnia poczucie komfortu użytkowania poprzez automatyzację obsługi urządzenia grzewczego. W artykule przedstawiono bieżącą sytuację na światowym rynku pelletu drzewnego, opisano podstawowe standardy jakości obowiązujące dla tego paliwa podczas produkcji oraz wskazano trudności w realizacji programów dofinansujących wymianę starych kotłów węglowych na kotły automatyczne 5. klasy na biomasę. Badania prezentowane w niniejszej publikacji ukazują problem, jakim jest obecność niedozwolonych zanieczyszczeń zarówno w certyfikowanym pellecie DIN Plus, EN Plus A1 jak i takim, który tego certyfikatu nie posiada. Badania te dowodzą, że stosowanie pelletów drzewnych, w których zastosowano niedozwolone substancje, wpływają negatywnie na pracę kotła, powodują powstawanie twardych spieków żużlowych i wprowadzają szkodliwe związki do atmosfery powodując, że to paliwo staje się nieekologiczne

An assessment of the efficiency and emissions of a pellet boiler combusting multiple pellet types

With sustainable energy being the key to reaching climate neutrality, the utilization of nonwooden biomass is a necessity. This article compares the emissions and efficiency of combusting a number of types of agrobiomass and wood pellets. A comparison was made on a moving grate pellet burner mounted in a boiler, where flue gas had a vertical flow via two pass heat exchangers with turbulization elements. Tests were conducted on wood pellets (ENPlus), miscanthus straw pellets, sunflower husk pellets, and corn stover pellets. During combustion, both wood and miscanthus pellets met the PN-EN 303-5:2012 emission and efficiency requirements. Corn stover pellets met the requirement on the nominal capacity. Sunflower husk pellets are characterized by excessive CO and particulate matter emissions. Sunflower husk pellets were the most problematic fuel from the point of view of the results of this research. During combustion of the miscanthus straw pellets there was a need to decrease the nominal heating capacity due to ash sintering

Emission Models for Selected Harmful Substances Emitted During Low-Temperature Combustion of Wood Pellets

The aim of the research was to develop mathematical models describing the emission of selected pollutants correlated with the residual oxygen content in the flue gas. The correlation was made for low-temperature combustion of wood pellets in biomass boilers and furnaces. The developed models can be used in modern control systems of boilers, furnaces or for precise calculation of emission factors for the discussed group of heating devices. The description was made for devices with a stationary wood pellet combustion process with a heat output range from 12 kW to 30 kW. The obtained models, not currently used in this group of devices, will allow controlling the operation of heating boilers in a sustainable and ecological way, taking into account the environmental burden

The Errors of Electronic Energy Meters That Measure Energy Consumed by LED Lighting

Various metrological aspects for the correct measurements of electrical energy that is consumed by energy-saving (mainly LED) single phase loads are discussed in this paper. One of the most important problems presented here concerns the question of how strong distortions of the current waveform, introduced by typical LED lighting, affects the operation of electronic energy meters. Measurement results for the energy consumption of different LED lamps used in households in various conditions, alongside comparative results that were obtained by electronic and electromechanical energy meters, were also offered and the appropriate conclusions were then drawn

Comparison of Emissions and Efficiency of Two Types of Burners When Burning Wood Pellets from Different Suppliers

Wood pellets play an important role among biomass materials used as fuel. At the same time, today’s economic, environmental, political and social realities, as well as other circumstances related to fuels used for heat generation, mean that there is demand for increasingly efficient and environmentally friendly combustion sources. As is well known, each combustion source has a different efficiency due to its intended use, design, principle of operation and the type and composition of the fuel burned. The amount of pollutants emitted into the environment during combustion also largely depends on these factors. The aim of this study was to compare the flue gas emissions and efficiency of two pellet burners of different design, burning certified A1 wood pellets from different suppliers. The emission requirements were met during the combustion of wood pellets in a boiler with the two burners tested (one with a moving grate and an overfed burner). The analyses and studies carried out aim to improve the capability of managing the efficiency and environmental performance of the heat source (i.e., a boiler or a burner) and the fuel (type of wood pellets). This is done in the context of demonstrating a better combustion source when selecting the right burner and fuel in terms of efficiency and emissions. In this paper, comparisons of flue gas emissions are presented along with characteristics in the form of graphs, as well as thermal and combustion efficiencies for the corresponding solid fuel used in the form of wood pellets. After comparing the emissions, it was found that the statistical averages of CO, NOx, dust and VOCs were similar for combustion at full power using the burners tested. Taking into account the pollution levels at combustion, it can be said that the difference in CO emissions at full and minimum combustion is lower for the experimental burner compared with the moving grate burner (reference burner). In summary, it can be concluded that the experimental overfed burner under consideration can be successfully used as a solid fuel boiler to burn wood pellets

Comparison of Emissions and Efficiency of Two Types of Burners When Burning Wood Pellets from Different Suppliers

Wood pellets play an important role among biomass materials used as fuel. At the same time, today’s economic, environmental, political and social realities, as well as other circumstances related to fuels used for heat generation, mean that there is demand for increasingly efficient and environmentally friendly combustion sources. As is well known, each combustion source has a different efficiency due to its intended use, design, principle of operation and the type and composition of the fuel burned. The amount of pollutants emitted into the environment during combustion also largely depends on these factors. The aim of this study was to compare the flue gas emissions and efficiency of two pellet burners of different design, burning certified A1 wood pellets from different suppliers. The emission requirements were met during the combustion of wood pellets in a boiler with the two burners tested (one with a moving grate and an overfed burner). The analyses and studies carried out aim to improve the capability of managing the efficiency and environmental performance of the heat source (i.e., a boiler or a burner) and the fuel (type of wood pellets). This is done in the context of demonstrating a better combustion source when selecting the right burner and fuel in terms of efficiency and emissions. In this paper, comparisons of flue gas emissions are presented along with characteristics in the form of graphs, as well as thermal and combustion efficiencies for the corresponding solid fuel used in the form of wood pellets. After comparing the emissions, it was found that the statistical averages of CO, NOx, dust and VOCs were similar for combustion at full power using the burners tested. Taking into account the pollution levels at combustion, it can be said that the difference in CO emissions at full and minimum combustion is lower for the experimental burner compared with the moving grate burner (reference burner). In summary, it can be concluded that the experimental overfed burner under consideration can be successfully used as a solid fuel boiler to burn wood pellets