Biomass Energy Plants Research Articles

Environmental and economic impacts of processing rice straw with water for energy and coproducts

Incorporating supplementary cementitious materials (SCM) such as rice straw ash (RSA) as cement replacement in concrete is a key path toward mitigating the contributions of cement to global climate change. A cost-benefit study and an environmental life cycle assessment (LCA) were performed to compute the impacts of water soaking, drying, and reverse osmosis (RO) of the leachate to factor in the use of rice straw as feedstock at biomass energy plants, RSA for concrete, and the RO-treated leachate as fertilizer and water for farms. The cost-benefit analysis showed that the sale of electrical energy from biomass, RSA, and fertilizer required further optimization of the processes to become profitable for the involved parties. The LCA showed a global warming avoidance equivalent to net -15kgCO2-eq per tonne of rice straw that could be achieved by substituting fossil fuel energy resources and cement avoidance in concrete.

Role of SbNRT1.1B in cadmium accumulation is attributed to nitrate uptake and glutathione-dependent phytochelatins biosynthesis

Phytoremediation of cadmium (Cd)-polluted soil by using sweet sorghum displays a tremendous potential as it is a fast-growing, high biomass and Cd tolerant energy plant. Previous study has demonstrated SbNRT1.1B expression change is in accordance with enhanced Cd accumulation by external nitrate supply in sweet sorghum. Nevertheless, underlying mechanism of SbNRT1.1B response to Cd stress is still elusive. SbNRT1.1B exhibited a positive response to Cd stress in sweet sorghum. Overexpressing SbNRT1.1B increased primary root length, shoot fresh weight, nitrate and chlorophyll concentrations compared with Col-0 under Cd stress, while complementary SbNRT1.1B rescued these decreased values in mutant chl1–5. Cd concentrations in overexpressing SbNRT1.1B, complementary SbNRT1.1B and Col-0 lines were 3.2–4.1, 2.5–3.1 and 1.2–2.1 folds of that in chl1–5. Consistent with Cd concentrations, non-protein thiol (NPT), reduced glutathione (GSH) and phytochelatins (PCs) concentrations as well as the related genes expression levels showed the same trends under Cd stress. GSH biosynthesis inhibitor failed to reverse the patterns of GSH-dependent PCs concentrations changes in different lines, suggesting that SbNRT1.1B plays an upstream role in GSH-dependent PCs biosynthesis under Cd treatment. Altogether, SbNRT1.1B enhances nitrate concentrations contributing to increased chlorophyll concentrations and GSH-dependent PCs metabolites biosynthesis, thereby improving growth and Cd concentrations in plants.

The economic price of biomass energy plantation in the implementation of cofiring in Indonesia

Abstract Biomass pricing plays an important role in ensuring the success of cofiring programs in coal-fired power plants. Higher prices will increase production costs, while setting lower prices may affect the sustainability of the biomass supplies. Therefore, determining the right price for biomass can provide a mutually beneficial solution between PLN and biomass industries. To determine the optimal price, it is necessary to calculate the price of biomass from the supply side (industry). It should have the minimum price that can still bring profits for the biomass industries. Fair economic prices are keys to creating an environment and business security that supports business development in the energy plantation (HTE) ecosystem for the implementation of cofiring.

Renewable energy plants: environmental compatibility and external costs assessment at global, regional and local scale

In Italy and many European countries energy production from biomass is encouraged by strong economic subsidies (in Italy up to 280 €/MWh granted through a feed-in tariff linked to the electrical production) so that biomass energy plants are getting large diffusion. Nevertheless, this kind of energy plant can involve heavy PM10, NOx, ammonia, methane and N2O emissions, as well as indirect emissions relating to cultivation, transport, fertilizers’ production. Within the described outline, the definition of the environmental compatibility as well as technological and economic issues dealing with the emerging renewable energy scenario is of primary importance. This evaluation should take into account global parameters as well as environmental impacts at regional and local scale coming from new polluting emissions. The environmental balances regarding new energy plants are of primary importance within very polluted areas such as Northern Italy where air quality limits are systematically exceeded. The paper analyses the energy and environmental performances of anaerobic co-digestion of manure and energy crops, wood and poultry manure combustion, involving the emissive balances, analysing different possible energy scenarios, using environmental economics tools like the ExternE methodology, an approach devoted to the assessment of the externalities associated to airborne pollution. The most important conclusion that can be drawn is that the production of renewable energy from anaerobic digestion, can strongly increase ammonia and NOx emissions and, in some cases, also GHG emissions could be worrying, whereas the application of best available techniques to waste gas cleaning and energy recovery allows positive environmental balances.

The Energy Yield of The Torrefied Coconut Shells

Woody and herbaceous biomasses have been utilized as biomass energy plant feedstocks that generate electricity for years. The coconut tree, classified as woody biomass, flourishes throughout tropical regions. Every year, each tree can produce an average of 70 nuts or a maximum of 150 nuts, with each fruit consisting of 15.18% shell. The Philippines has approximately 2.2 million tons of coconut shells each year. The study aims to determine the energy yield of the coconut shells when torrefied. The coconut shells were crushed, torrefied, and analyzed elementally. Initially, the calorific value of raw coconut shells was 30.79 MJ/kg and improved to 34.37 MJ/kg after torrefying at 275°C and held for 30 minutes. The optimal mass yield was 90.10%, while the energy density was 111.64%, resulting in an energy yield of 100.59%. Torrefaction improved the calorific value of coconut shells by 11.63% and optimized the energy yield to 100.59%.

Effects of cadmium on mercury accumulation and transformation by Arundo donax L.

High biomass energy plants are a promising alternative to hyperaccumulators for the remediation of heavy metals (HMs). Arundo donax L. (A. donax) is a rapidly growing rhizomatous grass with high biomass production. However, the feasibility of using A. donax for the phytoremediation of combined mercury (Hg) and cadmium (Cd) pollution under neutral conditions is unclear. In this study, a hydroponic experiment was performed to investigate the impact of Hg-Cd stress on the growth and physiological properties of A. donax and HMs accumulation and transformation. Either single Hg or Cd stress slightly enhanced stem height, fresh biomass, and chlorophyll content, whereas combined Hg-Cd stress reduced these parameters. Furthermore, combined Hg-Cd stress increased the leaf content of malondialdehyde in A. donax, indicating that the combined pollution aggravated oxidative stress in A. donax. Hg volatilization was observed during the 10-day experiment, implying that a portion of the Hg2+ was transformed into Hg0 by A. donax. The bioaccumulation factor (BAF) values of A. donax were far greater than 1 for both Hg and Cd, whereas the translocation factor (TF) values were less than 1, indicating that phytovolatilization and phytostabilization rather than phytoextraction contributed to the remediation of Hg and Cd by A. donax. The solution pH decreased at the beginning of the experiment, suggesting that acidic root exudates of A. donax facilitated the accumulation and transformation of Hg under neutral conditions. Overall, the effects of Cd on Hg accumulation and transformation by A. donax followed the rule of "low promotion and high inhibition." This study demonstrates that A. donax is a potential candidate for the phytoremediation of combined Hg-Cd pollution under neutral conditions.

Performance Analysis of Bio-Energy Based Power Generation System in Nigeria Using Rice Husk Feedstock

Bio-energy which is the energy resources derived from organic matter has contributed significantly to primary energy supply in most developed countries of the world. The extensive use of biomass for electricity generation started recently as a more efficient option of providing energy. To encourage investment in this area, detail analysis on the prospect of Biomass energy generation system in Nigeria context need to be carried out. In line with this, this study assesses the viability of setting up a Biomass Energy Plant in Nigeria using rice husk. It determine the availability of rice husk for the project and identify the economic advantage of using rice husk as a feedstock in generating electricity while evaluating the energy conversion technology adopted with consideration on its environmental impact. The proposed plant location is Abakiliki Rice Mill complex and Gasification technology was adopted for the bio conversion process. Data on the feedstock availability was collected by direct measurement of the resources at the various mill dump site in the Rice Mill Complex and analyzed using Python analytical and visualization tools (Numpy and Seaborn). The primary source of data for the analysis is data gotten from the field and Nigeria Energy Regulatory Council (NERC) while the secondary source of data is data from related work over the internet. The outcome of the study showed that the Rice Complex have the capacity to produce the quantity of rice husk required to generate 499,320KWh of electricity per year using Bio-Energy plant. Also, the mass of rice husk produced is significantly higher in the month of October, November and December due to the weather condition (dry season) and the high demand of rice as the result of the festivity (Christmas celebration). When the performance of the existing system and the proposed Bio-Energy plant was compared in terms of per Kilowatt cost of energy generation, it was observed that the new system outperformed the existing one. This is traceable to the good caloric value of rice husk and its availability in very large quantity at no cost. To determine the system’s sustainability, the financial feasibility of operating a Biomass plant in Nigeria was also carried out; levelised cost, simple payback period and return on investment (ROI) as important financial metrics were calculated using real data.

Geographical information system based fuzzy multi criteria analysis for sustainability assessment of biomass energy plant siting: A case study in Queensland, Australia

Biomass energy has huge potential in helping to achieve a renewable energy target to combat climate change. Many countries like Australia have huge potential for biomass energy supply from second generation biomass resources, however, the limited knowledge on the potential of these biomass resources could be a barrier to its uptake. This study developed a geographical information system based fuzzy multi criteria analysis (GIS based Fuzzy-MCA) to identify and prioritise the suitability of biomass energy plant sites for the sustainable use of biomass. The analysis was carried out in Queensland, Australia as a case study, demonstrating the potential of multiple biomass types for multiple products (thermal energy and bioelectricity supply). Using local sustainability constraints and criteria, the study identified potential biomass energy plant (57) sites in the East, South-East and North-West regions of the state where there are vacant lands and required infrastructure. Moreover, the high-resolution assessment of sustainably available biomass can have a significant impact on suitability of the location and the plant capacity. The potential biomass energy plants could generate electricity satisfying a substantial portion of Australian bioelectricity goals and mandates. The methodology could further be used in national-scale assessment, considering biomass incentive programs and government policies to maximise public benefit and private investment.

New Methods for Assessing Sustainability of Wood-Burning Energy Facilities: Combining Historical and Spatial Approaches

Methods to assess wood-based bioenergy projects have tended to focus on technological and physical constraints. Less is known about how longer-term environmental, economic, and social systems—the three pillars of sustainable development—have influenced technological development in the context of woody biomass energy. This research offers new methods for assessing the sustainability of wood-based energy projects by combining spatial analysis, semi-structured interviews, and archival data analysis. By integrating quantitative and qualitative methods, this project offers ways to understand how social and environmental dynamics from the past shape technological development in the future. A propensity analysis of biomass energy plants in Michigan, USA was performed using US Census data grouped by social, economic, and environmental categories. This quantitative analysis helped to characterize community and landscape types in which woody biomass plants were developed in Michigan in the late-twentieth century. To help illustrate some of the often-hidden social and political dimensions of energy development, such as access to decision-making and attitudes toward bioenergy projects, transcripts of public hearings, media coverage, and other archival sources were examined, and 30 stakeholder interviews were conducted. By integrating these qualitative and quantitative approaches, this paper aims to provide a more comprehensive approach to assessing the sustainability of wood-based biofuel technologies.

The impact of the planting of forest biomass energy plants under the embedded Internet of Things technology on the biodiversity of the local environmental ecology

Among a variety of renewable energy sources, only the use of forest biomass instead of fossil fuel is an excellent choice, because forest biomass is not only rich in reserves, but also has a relatively small impact on the local ecological environment after its consumption. Because the current development technology for forest biomass energy is not yet mature, the use of energy is relatively low. Therefore, it is imperative to construct a relatively standardized calculation model for forest biomass energy. To build a calculation model for forest biomass energy, it is necessary to rely on new technologies such as sensing technology, big data technology, and precise calculation control, especially biomass power generation and the demand for IoT technology from multiple energy sources. Based on the comparative analysis of the various parts of forest biomass energy, and relying on the overall framework of the Internet of Things technology, this article finds the integration point for the application of the Internet of Things technology in forest biomass energy and biodiversity monitoring. Through the use of PSCAD software, the planting of biomass energy plants was simulated, the composition type of forest biomass energy resources was determined, and the estimation model of forest biomass energy resources was established based on the bottom-up method, and its possible impact Carried out analysis and discussion. In the follow-up work, electromagnetic transient simulation software was used to simulate the planting of biomass energy plants, so as to determine the composition structure of forest biomass energy, and construct the calculation model of forest biomass energy using the method of linking up and down, and In-depth research on its possible impact. In view of the possible energy grid connection problems, solutions are proposed, and simulation experiments are carried out. Based on the actual construction data, the electromagnetic transient simulation software is used for simulation. The results show that the method in this paper can effectively provide data simulation for the development and utilization of forest biomass energy. • It is imperative to construct a relatively standardized calculation model for forest biomass energy. • To build a calculation model for forest biomass energy. • Internet of Things technology in forest biomass energy. • Possible energy grid connection problems.

Spatial optimization of multiple biomass utilization for large-scale bioelectricity generation

This study developed a geographical information system-based methodology to maximize the environmental and economic efficiency of large-scale energy plants using different types of biomass. As a precursor to the optimization modelling, multi-criteria spatial analyses and then transport cost optimization are applied taking into account spatial biomass availability and existing road networks, in order to identify optimal biomass energy plant sites for different combinations of biomass types. A geographical information system integrated with a capacitated maximal covering location problem model was employed to assign biomass supply points to biomass energy plants. Capacity limits of the plants and a defined maximum transportation distance were taken into consideration. The resulting information was used to examine major challenges in establishing a large-scale biomass energy plant, biomass supply logistics, environment cost and anticipated traffic congestion. A sensitivity analysis was also carried out to review the influence of plant capacity and maximum transportation distance on economic and environmental sustainability. The proposed methodology was employed utilizing agricultural and forest residues for bioelectricity generation in Queensland, Australia. It was found that 100% bagasse had the highest eco-efficiency for bioelectricity generation from multiple biomass combinations. In contrast, the combination of 70% sawmill residues and 30% forest harvest residues showed the lowest level of traffic congestion (2 trucks per hour). In addition, the impact of traffic congestion of bulky sugarcane residues can be reduced by adding forest residues to the biomass supply. The advantages of the resulting solution are further enhanced when social impacts such as energy security, new income opportunities and job creation are taken into account in addition to the sustainability aspects.

An Assessment on the Biomass Energy Resources for the Province of Laguna, Republic of the Philippines

Biomass is one of the very important fuel sources in developing countries, in case of the Philippines. Thus, the energy extracted from these resources can provide several advantages in terms of energy security, socio-economic development, and environment. An illustrative case study is conducted for the whole province of Laguna, Philippines, in order to utilize the energy assessed from biomass, particularly on the livestock waste exploitation on cattle, swine, and poultry. The assessed energy potential for Laguna may lead to have a solution for energy crisis and environmental concerns. The researchers have visited the six (6) local government units of Laguna, namely the cities of Binan, Sta. Rosa, and Calamba, and the municipalities of Los Banos, Calauan, and Cabuyao, in order to gather data and information. Several data from other farms in some areas in the Philippines are also provided, in order to develop a mathematical model that allows the estimation of the electricity consumption in the farm. The evaluation and ultimate selection of the most appropriate livestock waste system is a multi-level and multi-criteria decision problem. This study thus utilizes the Weighted Decision Making (WDM) for problem structuring and eventual ranking of the livestock waste systems. Finally, the location of the proposed biomass-energy plant is determined by utilizing the graphical representation method.

A Model for Selecting a Biomass Furnace Supplier Based on Qualitative and Quantitative Factors

In developing countries, solar energy is the largest source of energy, accounting for 35%–45% of the total energy supply. This energy resource plays a vital role in meeting the energy needs of the world, especially in Vietnam. Vietnam has favorable natural conditions for this energy production. Because it is hot and humid, and it has much rainfall and fertile soil, biomass develops very quickly. Therefore, byproducts from agriculture and forestry are abundant and continuously increasing. However, byproducts that are considered natural waste have become the cause of environmental pollution; these include burning forests, straw, and sawdust in the North; and rice husks dumped into rivers and canals in the Mekong Delta region. Biomass energy is provided in a short cycle, is environmentally safe to use and is encouraged by organizations that support sustainable development. Taking advantage of this energy source provides energy for economic development and ensures environmental protection. Due to the abovementioned favorable conditions, many biomass energy plants are being built in Vietnam. Like other renewable energy investment projects, the selection of the construction contractor, the selection of equipment for the installation of the power plant, and the choice of construction site are complex multi-criteria decisions. In this case, decision-makers must evaluate many qualitative and quantitative factors. These factors interact with each other and it is difficult to use personal experience to choose the optimal solution for such complex decision-making problems, especially in a fuzzy decision-making environment. Therefore, in this study, the authors use a Multi-Criteria Decision-Making (MCDM) model that uses a Fuzzy Analytic Hierarchy Process (FAHP) model and the Combined Compromise Solution (CoCoSo) algorithm to select biomass furnace suppliers utilizing both qualitative and quantitative factors. Furthermore, the results of this work will provide the first look at a hybrid CoCoSo/FAHP method that decision-makers in other fields can use to find the best supplier.

Natural Variation of Lignocellulosic Components in Miscanthus Biomass in China.

Lignocellulose content is an important factor affecting the conversion efficiency of biomass energy plants. In this study, 179 Miscanthus accessions in China were used to determine the content of lignocellulose components in stems via acid hydrolysis and high-performance liquid chromatography. Results showed that the average lignocellulose content of wild Miscanthus germplasm resources was 80.27 ± 6.51%, and the average content of cellulose, hemicellulose, lignin, extracts, and total ash was 38.38 ± 3.52, 24.23 ± 4.21, 17.66 ± 1.56, 14.50 ± 5.60, and 2.53 ± 0.59%, respectively. The average lignocellulose content of M. sinensis, M. floridulus, M. nudipes, M. sacchariflorus, M. lutarioriparius, and the hybrids was 77.94 ± 6.06, 75.16 ± 4.98, 75.68 ± 3.02, 83.71 ± 4.78, 81.50 ± 5.23, and 74.72 ± 7.13%, respectively. In all the tested materials, the highest cellulose content was 48.52%, and the lowest was 29.79%. Hemicellulose had the maximum content of 34.23% and a minimum content of 15.71%. The highest lignin content was 23.75%, and the lowest was 13.01%. The lignocellulosic components of different ploidy materials were compared. The content of lignocellulosic components of diploid M. sacchariflorus was higher than that of tetraploid M. sacchariflorus, and the content of lignocellulosic components of diploid M. lutarioriparius was lower than that of tetraploid M. lutarioriparius. Analysis of the relationship between the changes in lignocellulosic components and geographical locations of Miscanthus showed that the holocellulose and hemicellulose content was significantly positive correlated with the latitude of the original growth location. Results indicated that the lignocellulosic components of Miscanthus resources in China are rich in genetic diversity.

A Geographical Information System based framework to identify optimal location and size of biomass energy plants using single or multiple biomass types

The highly dispersed nature of biomass sources and limited tools with which to exploit geographically explicit data to minimise delivery costs are major barriers to the initiation of biomass energy projects. This paper presents a geographical information system based approach in combining suitability analysis, spatial biomass assessment and optimality analysis to locate plants for bioelectricity generation with sustainable availability of single or multiple biomass. First, fuzzy multi-criteria analysis was employed to identify the suitability of plants’ locations, using local economic, environmental, and social sustainability criteria. As well, the availability of multiple types of biomass was assessed. Biomass availability information and land use data were combined to generate high-resolution spatial biomass information with user-defined resolution. Next, a location-allocation model was used to identify optimal locations for biomass energy plants by considering both road networks and spatially distributed biomass availability. Additionally, different scenarios were analysed to optimise plant sizes, biomass delivery costs and total number of plants for the region under both single biomass and multi-biomass approaches. The developed model was demonstrated for a Queensland case study using sugarcane waste alone and combined sugarcane waste and forest waste. Results using sugarcane waste in Queensland identified optimally located plants with sizes from 57 MW to 185 MW and average transportation distances of 27 km to 64 km. By combining sugarcane waste with forest waste, the plant sizes increased, depending on spatial biomass availability. This methodology can be extended to evaluate optimum configuration and optimum combination of different biomass types at a plant level.

Air particulate matter dispersion at biomass energy plant using AERMOD Modelling

Biomass is included as one of the conventional sources other than solar and hydro energy. There are different types of biomass such as empty fruit bunch (EFB), fronds, mesocarp fibre (MF), trunk and shell. Each type provides a different level of particulate matter and the particulate matter had already emerged as one of the most critical pollutants. The main purpose of this paper is to identify the critical location on-site and to measure and analyse the particulate matter dispersion by using AERMOD Modelling. This paper presents a simulation study of particulate matter dispersion at biomass energy plant. The dispersion of the particulate is studied at Bioenergy plant located at Jengka, Pahang which generates electricity from the EFB waste. The shredded EFB had produced abundant of dust and particulate matter which suspends in the air and deteriorating the air quality. Thus, the dispersion of particulate matter pollutant by the biomass power plant is a rising concern. The influence of other operating variables were studied (temperature, relative humidity, wind speed, wind direction and activity). This paper also compares the concentration of PM2.5 and PM10 disperse from a location that had been marked as critical. From the result, the average concentration of particulate emitted to the air in 24-hour mean is 0.6944 mg/m3 for both size. Based on the guidelines provided by the World Health Organization (WHO), the concentration of both PM2.5 and PM10 are exceeding the level of 24 hour mean of emission and can be concluded as critical.

Torrefaction of oat straw to use as solid biofuel, an additive to organic fertilizers for agriculture purposes and activated carbon – TGA analysis, kinetics

In this paper authors present research results which are the optimum parameters of the torrefaction process using straw from oats and maize. The most important parameters for the torrefaction process are temperature and residence time. Both parameters are essential to designing and construction of industrial biomass torrefaction installations. Energy crops and waste coming from agricultural production have the most promising perspective from all kind of renewable energy sources in Poland. Currently, intensive studies on the process of biomass torrefaction are being carried out. In this experimental investigation, authors examined the torrefaction process of two types of agriculture biomass, such as: oats, maize. The main overarching objective of the experimental studies described below is the development of various biochar as an additive to agricultural fertilizers resulting from the conversion of biomass from agriculture residues – straw from oats and maize. The last of enumerated biomasses is treated through different conversion processes such as: drying, torrefaction to homogenize their physical and chemical properties. Among many of its areas, it is extremely important to optimize the production of biomass energy plants and its refinement (in the torrefaction process), which will improve the balance and profitability of energy production from RES, and reduce the logistics and storage costs of this fuel and improve the efficiency of biomass combustion process. When implementing new technologies indicated in this work and optimizing the harvesting of plant biomass, the negative impact on the environment caused by stored municipal waste can be reduced. This biomass torrefaction process temperature and residence time were necessary for the design and construction of semi-pilot scale biomass torrefaction installations with dryer and torrefaction reactor to perform a continuous biomass torrefaction process using superheated steam

Renewable Energy on Tribal Lands: A Feasibility Study for a Biomass-to-Energy Plant on the Cocopah Reservation in Arizona

Native American reservations are among the most economically disadvantaged regions in the United States; lacking access to economic and educational opportunities that are exacerbated by “energy insecurity” due to insufficient connectivity to the electric grid and power outages. Local renewable energy sources such as wind, solar, and biomass offer energy alternatives but their implementation encounters barriers such as lack of financing, infrastructure, and expertise, as well as divergent attitudes among tribal leaders. Biomass, in particular, could be a source of stable base-load power that is abundant and scalable in many rural communities. This case study examines the feasibility of a biomass energy plant on the Cocopah reservation in southwestern Arizona. It considers feedstock availability, cost and energy content, technology options, nameplate capacity, discount and interest rates, construction, operation and maintenance (O&M) costs, and alternative investment options. This study finds that at current electricity prices and based on typical costs for fuel, O&M over 30 years, none of the tested scenarios is presently cost-effective on a net present value (NPV) basis when compared with an alternative investment yielding annual returns of 3% or higher. The technology most likely to be economically viable and suitable for remote, rural contexts—a combustion stoker—resulted in a levelized costs of energy (LCOE) ranging from US$0.056 to 0.147/kWh. The most favorable scenario is a combustion stoker with an estimated NPV of US$4,791,243. The NPV of the corresponding alternative investment is US$7,123,380. However, if the tribes were able to secure a zero-interest loan to finance the plant’s installation cost, the project would be on par with the alternative investment. Even if this were the case, the scenario still relies on some of the most optimistic assumptions for the biomass-to-power plant and excludes abatement costs for air emissions. The study thus concludes that at present small-scale, biomass-to-energy projects require a mix of favorable market and local conditions as well as appropriate policy support to make biomass energy projects a cost-competitive source of stable, alternative energy for remote rural tribal communities that can provide greater tribal sovereignty and economic opportunities.

Kebijakan Pengembangan Budidaya Tanaman Bambu untuk Pengelolaan Berkelanjutan DAS Aesesa Flores

The existence of Aesesa Flores (AF) watershed is very important for people in Ngada and Nagekeo Regency of Flores island. The AF watershed provides water, land use, economic and other environmental services. However, the excessive exploitation is a major threat for the existence of the AF watershed. The degradation of the AF watershed function such as reduction in river debit, increase of critical land, land use change as well as the problem of poverty. The upstream area is intended as a conservation area where Watu Ata nature preservation park is located, the bamboo forest and Bajawa as the capital city of Ngada Regency. The downstream area is not only as capital city of Nageko Regency but also as paddy field area. One of the activity to improve the watershed function is through a comprehensive and sustainable management policy design based on characteristics and carrying capacity of the AF watershed. This research was conducted in April-May 2018 and the the purpose of the study is to analyzed key factors and establishing an alternative for sustainable management policy development of AF watershed using a prospective method. This study using mainly primary data obtained from the seven local experts through the filling of the questionnaire. The result shows that there are 22 attribute factors and it identified as 10 key factors. The main two key factors are bamboo cultivation, processing technology of bamboo, enlargement of bamboo cultivation area and practicing the soil and water conservation technique. The 10 key factors then become input for designing the management policy of AF watershed. Bamboo become the dominant and key factor because bamboo could be developed into biomass energy plant and it serves social, economic and ecological values for the local people of Ngada and Nagekeo Regency. Bamboo cultivation has a good prospect financially for the local people.

Pollutant emissions of a biomass gasifier inside a multifuel energy plant

Several benefits in clean energy and pollutant emissions can be offered from biomass energy application. This research analyzes a biomass gasifier installed at the University of Perugia and presents the description of a multifuel biomass energy plant with all its components: the combustion chamber and the heat exchanger, installed to supply the thermal input to the turbine, with 100 kW electric power and 1 MW thermal power.The application of a Computational Fluid Dynamics (CFD) prediction model can help to better understand the knowledge on chemical and thermofluidodynamic features linked to pollutant emissions. A numerical modelling based on Ansys Fluent code is realized with the aim to reproduce the behaviour of the gasifier. Two different stoichiometric woodchips:air ratios are taken into account in the numerical calculations. Experimental tests have been conducted to validate the results of the numerical analysis.The obtained results show that the experimental and the numerical analysis with the 1:5 stoichiometric ratio are comparable. The influence of the woodchips:air stoichiometric ratio on the temperature distribution that may be reached inside the gasifier is highlighted. The relationship between woodchips:air stoichiometric ratio, temperature and NOx emissions is considered. Furthermore, a comparison between the values of NOx and CO pollutants obtained with the numerical model and experimental tests has been done. The gasification process contributes to the production of renewable energy and it can be combined with other energy cycles (e.g. Organic Rankine Cycle).The novelty of the work consists in the definition and validation of a method for the analysis of the operating temperatures of the gasifier to verify how they can be combined with other heat exchange systems and in the analysis of the pollutants during the gasification process.