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The use of hydrogen as a fuel requires as much research as possible on the construction and functional parameters for the development of appropriate burners. The researches undertaken are addressed to diffuse flame burners with concentric jets of fuel and air. These burners cannot lead to flame return, the combustion being much safer, than for the case of burners with fuel-air mixture. The researches were carried out by numerical modeling through the ANSYS-FLUENT V.14.0 software. An important stage of the research, carried out theoretically, included the establishment of the hydrogen velocity at the exit of the burner section. Compared to this size, the question of the level of air velocity in the accompanying jet was further raised. It simulated operation with both a low level of air velocity and a high level up to the value of the fuel speed. The processing of the obtained data demonstrated the superiority of the flames with high air velocities, but also the great concordance between the flame obtained at the combustion of hydrogen with that of methane. The numerical modeling aimed at determining the conditions of hydrogen combustion for a hydrogen-air coaxial admission for the realization of methane-like flames. This also responds to the behavior of the hydrogen flame in the combustion chambers of the gas turbines, which are intended to modify the burner and not the room itself. The fact that the length of the hydrogen flame was about 10% below that of the methane flame also gives a positive response to this technical application. If in gas turbines the fuel compressor can provide hydrogen speed at the outlet of the burner, for other industrial applications there remains an open problem of ensuring hydrogen pressure. [ABSTRACT FROM AUTHOR]

The topic addressed in this paper is related to two waste management (poultry manure) objectives: reducing environmental impact through combustion, and energy generation. Poultry industry waste is produced in large amounts and cannot be always used as a fertilizer. Its storage needs large sites, but if they are improperly designed could affect the phreatic groundwater. The paper is organized as it follows. The first part presents the energy characteristics the waste samples analyzed (they come from a poultry farm, which beds the floor with cereal straw or sawdust; relatively to the waste mass, the bedding represents about 5% to 15%). The samples are taken from an intermediate warehouse located between the production halls and the central warehouse of a large capacity poultry farm. Regarding the location, the poultry farm is placed in the center of the historical region of Moldova, in Romania. From an exclusively energetic point of view, differences between the two beddings are not significant, since they both belong to the biomass class; if the biomass bedding lacks (very rare), the energy characteristics of the poultry manure get worse. The second part introduces a technology suitable for this kind of waste combustion. Starting from the energy properties, thermal conditions for ignition and flame support are investigated. The boiler types adequate for the process are specified, appropriate thermal power range is indicated. Considering the very difficult manipulation of this particular waste, its use is recommended for thermal energy production. Local utilization is taken into consideration, especially for heating purposes, for instance of the production halls. According to the results of this study, boilers equipped with mobile grate combustion installations and using gaseous or liquid hydrocarbons fuel aid are expected to have good yields for energetic valorization of poultry waste. [ABSTRACT FROM AUTHOR]

The experimental research has highlighted the variety of possibilities of combustion of animal fat from bovine and swine mixed with liquid hydrocarbons. Previous research has established that the upper limit for an efficient combustion was 30%. For a perfect mixing, the lower temperature limit was set to 40 °C. In the fuel laboratory, at the department TMETF was determined the viscosity of the mixtures for different proportions. The values obtained for various concentrations and preheating temperatures were close to the values for liquid hydrocarbons. The experimental researches have studied the combustion of the mixture using a mechanically spraying burner with constant pressure between 14 and 18 bar. The aspiration of the mixture is done from a specially designed tank; this tank is equipped with an electric heater, in order to maintain the mixture at a constant temperature between 40 °C to 50 °C. After that, the burner heats again the mixture with an integrated heating device up to 75 °C. The burner is also equipped with an air blower, pump and a calibrated nozzle. The combustion resulted from the experimental boiler with a power rated to 55 kW were monitored with a thermal vision camera and an exhaust gas analyser. This research has demonstrated the viability of using this type of mixtures in energetic burning equipment designed for liquid hydrocarbons. [ABSTRACT FROM AUTHOR]

The first part of the paper analyses the role of renewable resources in the production of electric and thermal energy in Romania. It was taken in consideration also the wood mass destined to heating the population, as a large number of households still use this fuel exclusively. Starting from the plough land and its associated production, there is the availability of agricultural biomass possible to use for energy production. The paper is concluded with the final considerations on the benefits of using biomass for energy production. As far as straw is concerned, a feasible long-distance transport option has not yet been found, so their use is limited to the range in which the trucks can be economically conveyed. The same is true for the case of energy willow or sorghum crops. For sorghum its fermentation is advantageous. For the biomass cultivator the following opportunities can be identified: Reduced storage costs; Reducing the environmental pollution and, implicitly, avoiding the sanitation costs of the adjacent area; Income generation through sales; Development of deprived areas and rational employment of the workforce. For the biomass consumer the following advantages can be mentioned: Reducing Renewable Fuel Costs vs. Conventional Fuels (Fuel, Natural Gas, Coal); as a rule, in Romania, agricultural biomass was imposed for the production of thermal energy; Reducing environmental costs. This is possible if it is considered that by using biomass as a fuel, CO2 emissions are considered to be zero compared to the use of conventional fuels under the Kyoto Convention. [ABSTRACT FROM AUTHOR]

This paper addresses the possibility of using poultry manure pyrolysis to obtain energy- efficient products. Poultry manure pyrolysis is the intended technology of combustion for both ecological and energy generation purposes, obtaining coke and gas fuel. The waste subjected to pyrolysis had a behaviour very close to that of the inferior coal. This is also confirmed by the elemental analysis; high moisture value raising issues when direct combustion is used. The combustion of the poultry manure through various technologies, including pyrolysis, using also another fuel, is a secondary result. Waste management represents a current major concern, especially for modern society who faces the pressing problem of their storage. Thermal treatment is a solution adopted in several circumstances. The results obtained show that waste behavior is very close to that of inferior coal. Power consumption for pyrolysis process falls within satisfactory limits; bellow the heat obtained by burning pyrolysis products. Pyrolysis fuel products, represented by semi-coke and coke, are likely to be used to produce energy. The paper presents a practical way of economic and ecological exploitation of the garbage from the poultry farms. [ABSTRACT FROM AUTHOR]

Wood was the most common source of energy on earth, being gradually replaced by fossil fuels. Given that the wood used in the generating stations comes from properly managed forests, then the carbon emitted from the chimneys can be annihilated by the carbon that is absorbed and used by the freshly planted trees. Wood can therefore be considered as carbon neutral. It remains to be seen if this theory is actually verified. Once it was decided to classify wood as a renewable source, its consumption increased exponentially. According to data provided by the International Wood Markets Group, a Canadian company, Europe consumed 13 million tons of wood briquettes in 2012. Based on the current trend, European demand for lighters will increase to 25-30 million tons per year by 2020. As a result, the price of wood is steadily increasing. Wood is not an exhaustible resource and it does not have a single price: a price statistic from Argus Biomass Market shows a price increase of lighters from 116 euro / ton in August 2010 to 129 euro / ton at the end of 2012. The regional supply of energy from renewable energy sources closes not only ecological but also economic circuits. Using biomass for energy provides significant environmental benefits: plants in the natural growth process consume CO2 from the atmosphere; while fold fuel generates GHG (their combustion represents about 2/3 of total carbon dioxide emissions). Advantages of using wood as a source of energy compared to fossil fuels: is a renewable resource; is available continuously and not intermittently; is a more environment-friendly energy resource than coal, being carbon neutral, as emissions to the atmosphere through combustion processes are offset by the absorption of carbon dioxide in the photosynthesis process of the forest. Romania's forests have a very high potential for biomass production for energy and industrial use. Until a few years ago, the use of biomass was mainly limited to household use by direct burning for home heating, cooking and water heating, accounting for about 95% of current biomass exploitation, while industrial biomass use was only 5% according to the 2010. Energy supply from renewable energy sources includes not only ecological but also economic circuits, making wood a safe and inexpensive fuel, an indigenous raw material, which brings added value to the exploitation area by creating new jobs. In this context, a sustainable management of the forestry fund is required through the implementation of the integrated forest management system integrated SUMAL. The main objectives of SUMAL are: a) increase the effectiveness of control as part of public policies to reduce crime in the forestry field, to prevent and combat illegal activities, by controlling the origin of the wood and ensuring its traceability; b) obtaining statistical information at national level on the volume of timber exploited and the resulting wood materials; c) unitary practice in the management of wood materials by providing a free IT application to professionals in the field. In carrying out this work we used qualitative research methods considering that qualitative research is based more on textual interpretation, requiring proper definition of the concepts or their scientific substantiation, highlighting the importance of the theme addressed. [ABSTRACT FROM AUTHOR]

This paper disseminates the research project, of wide impact, regarding HOLISTICS OF THE RENEWABLE ENERGY SOURCES ON ENVIRONMENT AND CLIMATE - HORESEC is to develop new instruments, methods, models, and technologies. These ones, based on evaluating the increase of share of renewable energy sources in the energy production and dynamics of the ratio between thermal and electrical energy, will lead to minimize the costs and maximize the efficiency. The project will present solutions tested on a pilot installation for adapting the renewable energy sources system to the dynamics of renewable energy share increase in the total energy production, including through long-term storage solutions. The HORESEC improvement of institutional capacity facilitates delivering high quality research services and, in the same time, increases the visibility at national and international level by disseminating the results. [ABSTRACT FROM AUTHOR]

This paper presents a solution for the replacement of conventional fuels with biofuels in order to protect the environment. The proposed biofuel is formed of diesel and a certain amount of animal fats. Biodiesel is similar to diesel fuel but with small differences. The animal fat is the result of the skin processes in the leather industry. In this industry it represents a waste and it is not used. We can consider that the animal fats are a renewable biofuel source. The proposed fuel has the properties of a renewable diesel. The method proposed in this article represents a recovery of this type of waste in the leather industry. The injection mode of this mixture, the flame length and the flame ignition temperature influence the proposed method. The burning of the mixture was done in a boiler Multiplex CL50. The injection of the mixture was performed with the ANYO- 12 burner. This paper presents the results obtained from numerical simulation using the software ANSYS-CFX for viewing the mixture characteristics. The simulations performed were realized for different diameters of the nozzle. The results showed that we can use the waste from animal fat for the burning process and to help to protect the environment by recovering this type of waste. [ABSTRACT FROM AUTHOR]

Different operations, such as fleshing, trimmings, cuttings and chips from hides, causes leather industry in being one of the most environmental 'unfriendly' sectors. Moreover, the treatment of sewage waters brings up also the problem of mud which is related with the appearance of biodegradation process of organic waste, followed by the emission of greenhouse gases, especially methane and nitrous oxide. All these wastes also imply a terrible smell and a strong land contamination. The large quantity of wastes, but also their variety led to a continuous process of developing new ways to treat and solve these problems by their recovery technically, economically and environmentally. In order to follow the general trend of energy recovery and the possibility of using in the system, there are distinguished two options: animal fat and biogas resulted from wastewater treatment and sludge discharged. One of the most favorable technological solution is the anaerobic digestion that decomposes a part of the organic matter contained in the tannery sludge and solid waste, by biogas production. [ABSTRACT FROM AUTHOR]