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Most climatic changes are not just the result of human activity, but also of business models that harm the environment. An attempt to attain an ecological balance is an answer to the challenge posed by this situation. The combustion of liquid fuels results in the atmospheric emissions of pollutants, such as nitrogen oxides (NOx), sulfur dioxide and hydrocarbons. To reduce emissions of these pollutants and at the same time attain an ecological balance, specific modifiers are applied. This paper presents an analysis of the energy efficiency and ecological efficiency of fuel oil combustion in power plant boilers based on the results of tests carried out by the present authors, in which a Fe/Mg/Ce modifier was used. The tests were carried out for system capacities ranging from 1 to 5 MW. It was found that savings on fuel, which resulted from the implementation of a system for the control and supervision of power plant operation, were in the range of 4 to 6%, and those resulting from the use of the combustion modifier were from 2 to 4%. Moreover, it was found that the system designed to improve efficiency also provided the extra result of reducing CO2 emission and equivalent emission (SO2, NO2, and particulate matter). [ABSTRACT FROM AUTHOR]

Our objective in this study was to assess the biodegradability and to calculate the percentage degradation for the modifier used in liquid fuel combustion processes and for sodium acetate (the reference material). We performed an assessment study evaluating high biodegradability in an aqueous environment using the manometric respirometry method (according to the OECD 301F guideline). Based on the results, it was found that the biodegradation of the test material reached 62.18% at the end of testing (after 28 days). On the other hand, the biodegradation of the reference material was at 85.94% at the end of our tests. [ABSTRACT FROM AUTHOR]

The combustion of liquid fuels (mainly of heavy fuel oils) generates pollutants such as carbon monoxide (CO), nitrogen oxides (NOx), sulfur dioxide (SO 2) and hydrocarbons (HC). Specific modifiers have been designed to reduce these environmental emissions by improving the combustion process. This research work presents the results of studies into the impact of a monometallic modifier comprising Fe salts, dimetallic modifier comprising Fe and Mg salts, and a trimetallic modifier comprising Fe, Mg and Ce salts, on the combustion of spent oils mixed with light fuel oil. The oil combustion tests were carried out in a 30 kW three-draft water boiler. The modifiers' impact on the combustion of the oil mixture was studied at varying air-excess values. The modifier was injected into the oil stream flowing into the boiler, by means of a dedicated applicator. The results indicate that the trimetallic modifier results in lower CO and NO x emissions but higher SO 2 emissions and higher boiler efficiencies than the dimetallic modifier. No catalytic activity was observed in the oil mixture combustion tests where the monometallic modifier was used. The benefits of using the modifier should be assessed on the basis of the cost of 1 Mg of fuel oil and the savings resulting from using the modifier and from the refurbishment. It was showed that depending on the capacity, savings due to the use of the modifier are in the range 2–4%, and those due to the system refurbishment are about 4–6%. For such savings, the return on the investment will occur after a period of time ranging from 3 years for large boiler plants to 5 years for smaller system capacities. All payback periods depend directly on the modifier system installation, on the modifier type, on the technical condition of the boiler plant and the costs of its refurbishment. Image 1 • Specific modifiers are added to heavy fuel oils to reduce emissions of pollutants. • The monometallic modifier shows no catalytic activity in the oil combustion tests. • The trimetallic modifier shows a higher activity than the dimetallic modifier. • Savings due to the use of the modifier depend on the boiler capacity. [ABSTRACT FROM AUTHOR]