Revaluation of bamboo as biomass

. Bamboo is a grassy plant that grows rapidly, is also a renewable natural resource and with a high yield. There are many applications and uses of bamboo, which led to its planting around the world. Among the industries in which bamboo has by now experienced extensive exploitation, we can remember the textile, construction, furniture ; even food, pharmaceutical or cosmetic industries. Biomass is the plant material that is used as a renewable energy resource. This is achieved others by cultivating plants specially used for energy production or by using resistors from small industrial sectors. The current paper highlights the potential for the recovery of bamboo as biomass, both in terms of the fact that bamboo is a plant that is believed to be an inexhaustible resource, but also for the wide amount of rest from its multiple uses.


Introduction
In recent decades, there has been a tendency to exploit biomass sources to replace traditional fossil fuels. Such a material capable of producing large amounts of biomass is the bamboo [1].
Biomass (vegetable material) is a renewable energy source which becomes more competitive compared to traditional energy production sources in terms of system installation expenses and energy production costs [1]. Biomass stores the energy it receives from the Sun using the process called photosynthesis. In biomass processing, whether it is incineration, pyrolysis or gasification, there is a release of the energy captured from the Sun and its transformation into other forms of energy. From this perspective, biomass can be seen as an accumulator that can store solar energy for long periods. [2]. Unlike batteries, however, biomass is a sustainable source of energy storage, and if sustainable crop management methods are applied, it is unlimited. Generally, there are two main approaches to the use of plants to produce energy (1) the cultivation of plants specifically for the use of energy and (2) the use of residues resulted from agricultural practices [3]. The best approach varies, depending on several factors such as conditions [4].
Biomass may be considered an abundant source of land surfaces and has a short life cycle, being a Energy crops are identified with the cultivation of annual or sustainable plants, at the industrial level, which are intended to provide biomass used to obtain various energy sources. Compared to other renewable sources of photovoltaic power, the energy produced from biomass nature, but can easily be stored in solid, liquid concluded that bioenergy is a stable resource of Bamboo is part of the Poaceae family, rye and rice. It can have up to 1250 species world [6].
The bamboo plants are fast-growing plants, representing a renewable and high natural resource.
Bamboo is known as "the plant of a thousand uses economic role, being also related to humanity Bamboo has common characteristics with many other biomass raw materials in terms of the heating value and chemical composition. of waste to energy involves the transformation of the row material into other forms of [8]. The bamboo characteristics may differ maturity of the plants, the season, or cultivation practices (e.g. production [9]. This paper is a brief synthesis of the highlighter o studied in literature.

Materials and methods
In the process of obtaining the carbohydrates that form the building blocks" of biomass, the CO 2 in the atmosphere, water and in the soil participate. If chemical energy is (biomass is burned), oxygen from the atmosphere and carbon from plants react by forming carbon dioxide and water ( fig.1). Since carbon dioxide can participate again in the biomass formation process, the process is cyclical [10 several factors such as climate, soils and geographical may be considered an abundant source of energy because covers a large part of , being an important candidate as an alternative fuel. with the cultivation of annual or sustainable plants, at the industrial level, which are intended to provide biomass used to obtain various energy other renewable sources of bioenergy such as wind powe or produced from biomass is an intermitted energy source in be stored in solid, liquids or gaseous forms. From this issue it can be bioenergy is a stable resource of auxiliary energy [5].
family, as well as corn, wheat, sugar cane, barley, oats, species from 75 genres and is spread around the growing plants, representing a renewable and high-yield the plant of a thousand uses", since plays an important sociohumanity since ancient times [7]. Bamboo has common characteristics with many other biomass raw materials in terms of the heating value and chemical composition. The commonly used conversion technologies of waste to energy involves the transformation of the row material into other forms of fuels differ depending on the species, plant section, the cultivation practices (e.g. fertilizer) and place of This paper is a brief synthesis of the highlighter of the biomass potential of bamboo In the process of obtaining the carbohydrates that form the building blocks" of biomass, in the soil participate. If chemical energy is extracted (biomass is burned), oxygen from the atmosphere and carbon from plants react by forming carbon dioxide and water ( fig.1). Since carbon dioxide can participate again in the biomass 10].
The elemental composition of vegetable biomass is shown in Figure 2. The size of the boxes corresponded to the amount of each element in the composition of biomass. The general composition and heating value of bamboo wood and the herbaceous material. The woody bamboo peaks, considered the most suitable bio-fuel.
Bamboo presents several advantages compared to The most important advantages are the higher crop yields and higher biomass densities both being important features that may lead to lower production and transport costs. addition, bamboo cropping doesn't need the total amounts of fertilizers required by the crops are also relatively low benefits in terms economy and of biomass value. Table 1 shows the average characteristics materials, that have been found in the literature [ The elemental composition of vegetable biomass is shown in Figure 2. The size of the boxes corresponded to the amount of each element in the composition of biomass.
The general composition and heating value of bamboo is found between the values of wood and the herbaceous material. The woody bamboo peaks, that are mature and dry, is compared to other lignocellulosic raw materials. higher crop yields and higher biomass densitieslead to lower production and transport costs. In doesn't need the utilization of seeds and plastics for baling. The s required by the crops are also relatively low. These are key benefits in terms economy and of biomass value.
characteristics of the plant compared to other biomass raw in the literature [8].
Biomass properties of bamboo compared to specific raw materials.

Methods for producing energy from bamboo
Apart from transesterification technique, transformation of waste biomass to energy is carried out using thermochemical and biochemical conversion [ procedures to recover energy from bamboo biomass. Thermochemical conversion can be performed:  By direct combustion. Direct combustion furnaces might be used for direct heat technologies, or for creating steam. Dry bamboo may be used for direct combustion industrial scale. The principle of combustion consists of mainly of carbon and hydrogen atoms under controlled conditions.  By pyrolysis processes, Pyrolysis is the phenomenon of thermal decomposition of biomass into highly heterogeneous gaseous, liquid, and solid intermediates, Therefore, it is a thermal degradation of organic materials at a temperature °C. The main products produced from the pyrolysis process consist of coal ( solid phase of the obtained product), condensable the liquid phase) and the condensable gases ( pyrolysis is usually performed accordingly to the processes found in Fig. 3. The diagram depicting combustion process  By gasification Gasification is the conversion of biomass into gases, such as: nitrogen (N2), carbon monoxide (CO), hydrogen (H2), and carbon dioxide (CO2). Gasification consists in a organic material at increased temperature under gasification process may include pyrolysis and partial combustion temperature, usually between 750 °C and 1200 °C.
The gasification process will have as products usually named syngas, and can be either used directly in the burners, or are desulfurized Methods for producing energy from bamboo crops biomass transesterification technique, transformation of waste biomass to energy is carried out using thermochemical and biochemical conversion [12]. There are many to recover energy from bamboo biomass. performed: Direct combustion furnaces might be used for direct heat technologies, or for creating direct combustion in small incineration units or on principle of combustion consists of burning the fuel, that is composed of carbon and hydrogen atoms under controlled conditions. Pyrolysis is the phenomenon of thermal decomposition of biomass into highly heterogeneous gaseous, liquid, and solid intermediates, in the absence of oxygen.
thermal degradation of organic materials at a temperature of 350 to 600 the pyrolysis process consist of coal (which is the ), condensable oils (heavy hydrocarbons), tars (which is condensable gases (which is called the gaseous phase). The performed accordingly to the processes found in Figure 3 [13].
Gasification is the conversion of biomass-or fossil fuel-based carbonaceous materials into gases, such as: nitrogen (N2), carbon monoxide (CO), hydrogen (H2), and carbon in a process of thermal and chemical conversion of temperature under special air intake conditions. The pyrolysis and partial combustion, occurring at a high temperature, usually between 750 °C and 1200 °C.
The gasification process will have as products syngas and ash. The gaseous products are usually named syngas, and can be either used directly in the burners, or are desulfurized and used in internal combustion engines. noncombustible gases. Approximately 40% of the volume of syngas can be used for generating electricity or heat. In practice atmospheric air is normally used quite expensive.

Biochemical conversion
In biochemical conversion, different strains of microorganisms that convert products from biofuels are used. The principle of biochemical conversion is the fermentation of sugars and other substances contained in biomass performed with the help of microorganisms ethanol, methane and other fuels, chemical and thermal.
Bioconversion can be performed either in the presence of air or in its absence  Anaerobic digestion (Figure 4) is a process through which bacteria break down organic matter (animal manure, wastewater biosolids, and food wastes) in the absence of oxygen, producing biogas (methane) (60%) and CO2 (40%) [1 Fig. 4. Anaerobic digestion path [11].
 Fermentation usually occurs in the presence of oxygen being the starch/sugar by microorganisms (yeasts and bacteria) to produce ethanol. pretreatment with acid and enzyme biomass turns into cellulose, which by hydrolysis becomes sugar which after fermentation turns into ethanol

Bamboo → Biomass → Cells → Sugar
Liquid fraction, also called the pyrolysis fuels biofuels. Syngas is usually burned in cogeneration plants for the production of electricity. In biochemical conversion, microorganisms to convert biomass into biofuels. The fermentation of sugars or other substances from bamboo biomass into (bio) ethanol, methane and other fuels.
Furthermore, bamboo has attractive fuel parameters being the high heat values, the high al combustion engines. Syngas is a mixture of combustible gases and noncombustible gases. Approximately 40% of the volume of syngas can be used for generating electricity or heat. In practice atmospheric air is normally used since oxygen is In biochemical conversion, different strains of microorganisms that convert various products from biofuels are used. The principle of biochemical conversion is the other substances contained in biomass. The processing is performed with the help of microorganisms which will produce different amounts of ethanol, methane and other fuels, chemical and thermal.
Bioconversion can be performed either in the presence of air or in its absence: is a process through which bacteria break down organic matter (animal manure, wastewater biosolids, and food wastes) in the absence of oxygen, producing biogas (methane) (60%) and CO2 (40%) [14].
usually occurs in the presence of oxygen being the decomposition of starch/sugar by microorganisms (yeasts and bacteria) to produce ethanol. By pretreatment with acid and enzyme at high processing temperatures, bamboo cellulose, which by hydrolysis becomes sugar which after Sugar → Ethanol.
pyrolysis fuels is processed into a biorefinery to produce is usually burned in cogeneration plants for the production of energy and electricity. In biochemical conversion, are usually used several different strains of microorganisms to convert biomass into biofuels. The technological flow involves the or other substances from bamboo biomass into (bio) ethanol, fuel production characteristics, the most important , the high volatile contents, the low ash and moisture content. This is why bamboo is considered an appropriate crop for production of bioenergy [15].

Results and discussions
Over the years, tests have been conducted to assess the energy potential of bamboo. Several research studies on this subject are highlighted in the following.
At Hasanuddin University, Tamalanrea, Makassar, Indonesia, the energy potential of bamboo leaf biomass has been verified.
In this study, bamboo leaves were used to conduct experiments according to temperature and heating time. Proximal analyses were used to determine first the volatile matter (VM). The ash content, the fixed carbon (CF) and moisture content (MC) have been also determined.
Have been used three prediction formulas to estimate the content of carbon, hydrogen and oxygen.
The dried bamboo leaves have been cleaned using distilled water, then a cutting process was applied, shredded and sifted at 500 μm until homogenized, after which they were heated to 250 °C, 300 °C, and 350 °C for 30, 60 and 90 minutes in -an environment devoid of oxygen.
The results of Table 2 [16] were obtained from the analyses. Bambusa vulgaris has been found to have characteristics that make it possible to use it as a primary fuel. Biomass consisting of strains of Bambusa vulgaris, without branches, has a high quality as it progresses from base to top and is between 1 and 3 years old. This observation is mainly due to the energy density analysis, which has higher values in the upper position and at the age of three.
The quality of the biomass Bambusa vulgaris as an energy intake improves with increasing age and in the upper parts of the stems, producing a greater amount of energy per unit of volume. The energy quality of Bambusa vulgaris was also investigated. Research has established that this species has a moisture content close to the maximum to generate energy (30%) 20.19%. In addition, the species under analysis can be used to increase the biomass base for energy production and to replace the wood that is used on large scale for this purpose [17].
Usually, the yield of bamboo biomass is no different within aspecies. However, following a fight at two locations in Thailand on two bamboo species, namely Bamboo becheyana and Dendrocalamus membranaceus, it was found that they may differ. As regards species D. membraneaceus the moisture content is lower while the calorific power is higher than that of species B. beecheyana, indicating that D. membranaceus. may be a more attractive option as a raw material for obtaining biomass [18].

Conclusions
Since bamboo is a very common plant used in different industries, this certainly leads to the production of numerous plant residues. They can be harnessed as biomass.
Over the years many researchers have studied the potential of bamboo to devein biomass and have shown that it lends itself to being a good raw material for the generation of plant biomass.
From the literature we can conclude that fossil fuels can be replaced with bamboo biomass, which is renewable and capable of producing different types of fuels, be they solid, liquid or gaseous.
For the transformation of bamboo biomass into another form of energy can be applied various technologies. These transformations provide new products such as coal, syngas, oil and ethanol.
Unlike wind and photovoltaic energy in addition to electricity production, bamboo biomass also produces biofuels.
As disadvantages we can say that bamboo biomass brings environmental risks by decreasing biodiversity, invasion of species and takes a long time to mature.
Although much research has been done in the field, in many countries energy projects from bamboo biomass are still being implemented.
To evaluate he sustainable mode of use and the capacity of this resource are necessary much more mute specialized studies.