Hawaii natural resource information system: A tool for biomass production management

The Hawaii Natural Resource Information System (HNRIS) is a geographical information system and database designed to facilitate the development and implementation of agricultural and environmental technology. Consisting of seven major data files, a set of resource retrieval and interpretation programs/models and a database maintenance/management program, HNRIS is a cost- and time-efficient tool to assist landowners, planners and other decision-makers in Hawaii in making critical land-use and natural resource management decisions. This paper describes the hardware, software and performance of HNRIS, and features an application of HNRIS to estimate yield and delivered cost of tropical hardwood feedstocks in a short-rotation woody biomass production system.     

Growth patterns and biomass productivity of two Salix species grown under short-rotation intensive culture in southern Quebec

Samples of two species of Salix, Salix discolor, which grows naturally in the northern half of North America and S. viminalis, which originated from central Europe, were studied to compare their productivity and their growth patterns under the short-rotation, intensive-culture system (SRIC). The study was conducted in the nursery of the Montreal Botanical Garden on former agricultural land. The plantation was established at a density of 27,000 trees per hectare from unrooted cuttings without any fertilizer or irrigation. Growth parameters were measured at regular intervals during summer of the two first years following planting. At the end of each growing season, after leaf drop, a part of each plot was cut down and the stems and branches were harvested and weighed to evaluate their annual growth rates and their biomass yields. For the first growing season, height growth in both species was greater than 2 m. Although S. viminalis grew more rapidly early in summer, S. discolor grew about three weeks longer and its total height at the end of the growing season was greater than the former. Meanwhile the stem-branch dry weight of S. discolor was similar to the one produced by S. viminalis. Two growing seasons after establishment, the total tree height was about 3.5 m for both species, while the biomass of stems and branches of S. viminalis was weakly superior in comparison to S. discolor and reached very high values-about 27 Mg ha⁻¹ for S. viminalis. The growth patterns and yields of the one-year-old coppice (one-year-cycle) were similar to those recorded at the end of the first year for trees developed directly from cuttings. Both species produced a comparable quantity of sprout biomass. The yield of the trees harvested two years after planting was about twice the total biomass harvested two times, at the end of each growing season, suggesting that a two-year cycle is more productive than a one-year cycle.     

Biomass productivity and wood energy of Salix species after 2 years growth in SRIC fertilized with wastewater sludge

The energy equivalent of willows in short-rotation intensive culture (SRIC) varies in terms of yield and woody biomass characteristics. Three willow species (Salix discolor Mühl., Salix petiolaris Smith and Salix viminalis L.) were planted on two sites, well-drained and poorly drained, in two different densities (20 000 and 30 000 plants per ha). Four doses of dried and granulated sludge were applied: the equivalents of 0, 100, 200 and 300 kg “available” N per ha. At the end of the second season, above-ground biomass was similar for S. discolor and S. viminalis, and greater than that of S. petiolaris on both sites and for all sludge treatments. On the well-drained site, each increment in the sludge dose significantly increased the performance of the species, regardless of plant density. Fertilized with a sludge dose equivalent to 300 kg N per ha, S. viminalis and S. discolor yielded 30.17 and 24.97 t/ha of dry matter respectively. On the poorly drained site, differences in performance were also observed between fertilized and unfertilized plots, but not among the various treatments. The calorific value of the wood of the three species being similar (19.21–19.59 kJ/g), the energy equivalent of a hectare of willows is proportional to the yield of each species. Thus the energy equivalent of S. viminalis and S. discolor is two to three times that of S. petiolaris. S. viminalis had the highest woody biomass quality, with an FVI (fuelwood value index) of 1030.58 (100%), followed by S. petiolaris with 954.25 (92.6%) and S. discolor with 849.08 (82.4%).     

Biomass and biohydrogen production during dark fermentation of Escherichia coli using office paper waste and cardboard

Growth properties, oxidation-reduction potential kinetics and hydrogen production of Escherichia coli BW25113 parental strain (PS) and hydrogenase (Hyd)-negative mutants were investigated after fermentative growth using office paper waste and cardboard (PW) hydrolysate (PWH). PWH was obtained by using dilute acid method in a steam sterilizer for 1 h, 121 °C. Optimal conditions for bacterial growth and H₂ production were identified (PWH concentrations, pH 7.5). Recording of redox potential using a platinum electrode revealed a drop to −500 ± 10 mV, with a H₂ yield of ~1.45 mmol H₂ L⁻¹ after 4 h of growth using PWH resulted in the formation of 0.20 ± 0.02 g bacterial cell dry weight L⁻¹. Bacterial biomass formation was stimulated ~3-fold upon addition of 0.5% yeast extract, and H₂ production started early - at the beginning of the exponential phase. Moreover, mutants lacking Hyd-1 and Hyd-2 significantly enhanced H₂ production. The findings would be beneficial for the development of H₂ production biotechnology using cheap solid waste materials.     

10 MW生物质气化耦合燃煤机组发电装置性能试验研究

某电厂生物质气化耦合燃煤机组发电项目于2018年9月8日完成72 h满负荷试运,项目主体是循环流化床气化耦合系统及附属设备,为评价该耦合系统的综合性能,进行了额定负荷下的产气率、气化效率、热效率及对燃煤机组煤耗影响等性能试验。试验结果表明:额定负荷下,生物质气化耦合系统以50%稻壳+50%秸秆作为原料时,燃料量为8. 61 t/h,产气率为2. 09 m~3/kg,气化效率为70. 53%,热效率为87. 65%;以100%稻壳作为原料时,燃料量为8. 57 t/h,产气率为2. 15 m~3/kg,气化效率为70. 04%,热效率为88. 12%;气化耦合系统在75%～110%负荷范围内可稳定运行;气化耦合系统额定负荷、燃煤机组维持600 MW负荷的情况下,投运气化耦合系统后,减少标煤量3 291 kg/h;气化耦合系统额定负荷、燃煤机组维持500 MW负荷的情况下,投运气化耦合系统后,减少标煤量3 122 kg/h。     

Biomass and energy production in Casuarina equisetifolia plantation stands in the degraded dry tropics of the Vindhyan plateau, India

Two age groups of Casuarina equisetifolia (Forst.) plantation stands in the Renukoot forest division of the Vindhyan plateau were investigated over the span of three years for total and component biomass, annual net primary production, energy storage and annual net energy fixation. A high range of biomass (44–81 t ha⁻¹) was recorded in a densely populated stand at ages 5–7 years in comparison to a sparsely populated stand at ages 8–10 years. The contribution of the hole component gradually increased with increasing diameter class while foliage and branch components had a large proportion of biomass in the lower diameter classes. Maximum litterfall occurred in May and foliage litter contributed 87–95% of total litterfall. The energy content and storage in component parts were higher than some other promising tree species for energy plantation in the dry tropics. Production estimates of 19–29 t ha⁻¹ yr⁻¹ showed that the performance of Casuarina is good for dry tropical conditions. The biomass accumulation ratio and production efficiency showed a significant positive and negative (logarithmic) relationship, respectively with plantation age. The energy conserving efficiency of the 5-year old stand was more than twice that of the 8-year old stand.     

流化床中生物质气化的数值模拟

基于欧拉多相流模型,自编化学反应子模型,通过建立生物质流化床气化动力学模型,对某实验室规模的流化床生物质气化炉进行了数值模拟,研究了蒸汽与生物质的质量比（mS/mB）、生物质粒径对产气组分、蒸汽分解率等的影响.结果表明：mS/mB增大,H2体积分数先上升后保持不变,而CO和CH4的体积分数先下降后几乎不变,蒸汽分解率下降;生物质粒径减小有利于气化过程,使CO和H2的体积分数明显上升;计算结果和试验结果基本吻合,表明基于欧拉多相流的动力学模型能对流化床中生物质的气化进行比较准确的模拟.     

Aspen Plus model of an alkaline electrolysis system for hydrogen production

A model of an alkaline electrolysis plant is proposed in this paper, including both stack and balance of plant, with the objective of analyzing the performance of a complete electrolysis system. For this purpose, Aspen Plus has been used in this work due to its great potential and flexibility. Since this software does not include codes for modelling the electrolysis cells, a custom model for the stack has been integrated as a subroutine, using a tool called Aspen Custom Modeler. This stack model is based on semi-empirical equations which describe the voltage cell, Faraday efficiency and gas purity as a function of the current. The rest of the components in the electrolysis plant have been modelled with standard operation units included in Aspen Plus. Simulations have been carried out in order to evaluate and optimize the balance of the plant of an alkaline electrolysis system for hydrogen production. Also, a parametric study has been conducted. The results show that increasing the operation temperature and reducing the pressure can improve the overall performance of the system. The proposed model in this work for the alkaline electrolyzer can be used in the future to develop a useful tool to carry out techno-economic studies of alkaline electrolysis systems integrated with other process.     

Biogas production from grape pomace: Thermodynamic model of the process and dynamic model of the power generation system

In year 2010, the Province of San Juan – Argentina (South America) produced around 81 947 tons of grape pomace, which is a winery waste by-product. Wineries demand a great quantity of power during the three months that winemaking time lasts, which involve a high installed electric power. This power is used mainly for refrigerating the must during the fermentation. The control of temperature is crucial in winemaking as the low temperature preserves subtle fruit characters. An alternative for reducing the requirement of power from the utility electric grid is producing it locally, using the residuals generated by the own wineries. The technology for bioenergy conversion proposed to be implemented in this research for electricity generation is the anaerobic digestion of grape pomace. The aim of this research is to develop the thermodynamic equilibrium analysis of grape pomace anaerobic digestion based on the equilibrium constants for predicting the potential production of biogas and its composition. In addition, a dynamic model of a biogas-fuelled microturbine system for distributed generation applications is derived.     

生物质超临界水催化气化制氢实验系统

生物质超临界水催化气化制氢是一项很有价值的离新技术,它有利于开发广泛的生物质资源,为大规模的制氢提供一条高效、清洁的途径。针对生物质超临界水气化制氢,国内外结合工作具体要求和条件,设计出了一系列生物质超临界水催化气化制氢的实验系统。主要对国内外几种较好的生物质超临界水催化气化制氢实验进行了综合评述,分析了各类实验系统存在的问题及待改进之处。     

A novel approach to simulate growth of multi-stem willow in bioenergy production systems with a simple process-based model (3PG)

An important requirement for commercialization of willow biomass production in short-rotation crop (SRC) plantations is the reliable and cost-efficient estimation of biomass yield. Predictions and simulations of willow stand biomass have been problematic due to issues with modeling the multi-stem growth form of willow. The aim of this paper was to develop a new approach for managing allometric measurements from multi-stemmed willow for stand growth simulations. The 3PG model (Physiological Principles in Predicting Growth) was parameterized for willow and was used for biomass yield simulation for an entire 22-yr cycle (seven 3-yr rotations) of willow in SRC plantations. The multi-stemmed growth form was transformed into a single-stem modeling form by deriving whole plant willow allometric relationships using detailed stem-level measurements of basal area, stem biomass and volume. 3PG model predictions for plant diameter, height, biomass, and stand biomass and volume were within the 95% confidence range of mean plot values. Model simulations showed that after seven 3-yr rotations only 20% of planted cuttings would survive (a decrease from 15,152 to 3022 plants ha⁻¹), but stand volume would increase continuously with each subsequent rotation. 3PG predictions for cumulative (for 22 yr) aboveground biomass was 272 Mg ha⁻¹ and mean annual yield was 12 Mg ha⁻¹ yr⁻¹, comparing favorably with other findings. To our knowledge, this work is the first where the 3PG model was calibrated and used for willow species. Once parameterized for a specific willow clone, 3PG can predict biomass accumulation for any agricultural land in North America using only available soil and climate data.     

Assessment of potential biomass energy production in China towards 2030 and 2050

The objective of this paper is to provide a more detailed picture of potential biomass energy production in the Chinese energy system towards 2030 and 2050. Biomass for bioenergy feedstocks comes from five sources, which are agricultural crop residues, forest residues and industrial wood waste, energy crops and woody crops, animal manure, and municipal solid waste. The potential biomass production is predicted based on the resource availability. In the process of identifying biomass resources production, assumptions are made regarding arable land, marginal land, crops yields, forest growth rate, and meat consumption and waste production. Four scenarios were designed to describe the potential biomass energy production to elaborate the role of biomass energy in the Chinese energy system in 2030. The assessment shows that under certain restrictions on land availability, the maximum potential biomass energy productions are estimated to be 18,833 and 24,901?PJ in 2030 and 2050.     

Methodology for modelling plug-in electric vehicles in the power system and cost estimates for a system with either smart or dumb electric vehicles

The article estimates the costs of plug-in electric vehicles (EVs) in a future power system as well as the benefits from smart charging and discharging EVs (smart EVs). To arrive in a good estimate, a generation planning model was used to create power plant portfolios, which were operated in a more detailed unit commitment and dispatch model. In both models the charging and discharging of EVs is optimised together with the rest of the power system. Neither the system cost nor the market price of electricity for EVs turned out to be high (36-263 €/vehicle/year in the analysed scenarios). Most of the benefits of smart EVs come from smart timing of charging although benefits are also accrued from provision of reserves and lower power plant portfolio cost. The benefits of smart EVs are 227 €/vehicle/year. This amount has to cover all expenses related to enabling smart EVs and need to be divided between different actors. Additional benefits could come from the avoidance of grid related costs of immediate charging, but these were not part of the analysis.     

环境低负荷制氢技术及集成制氢系统

讨论了各种环境低负荷的制氢技术。SPE电解水制氢技术成熟,将成为未来主要制氢方法之一。生物化学制氢和半导体光解水制氢仅以太阳能为能源,前景广阔。生物质制氢清洁、节能,值得推广。环境低负荷集成制氢系统综合多种技术,是制氢技术发展的一个趋势。     

Investigation of a novel & integrated simulation model for hydrogen production from lignocellulosic biomass

Process simulation and modeling works are very important to determine novel design and operation conditions. In this study; hydrogen production from synthesis gas obtained by gasification of lignocellulosic biomass is investigated. The main motivation of this work is to understand how biomass is converted to hydrogen rich synthesis gas and its environmentally friendly impact. Hydrogen market development in several energy production units such as fuel cells is another motivation to realize these kinds of activities. The initial results can help to contribute to the literature and widen our experience on utilization of the CO₂ neutral biomass sources and gasification technology which can develop the design of hydrogen production processes. The raw syngas is obtained via staged gasification of biomass, using bubbling fluidized bed technology with secondary agents; then it is cleaned, its hydrocarbon content is reformed, CO content is shifted (WGS) and finally H₂ content is separated by the PSA (Pressure Swing Adsorption) unit. According to the preliminary results of the ASPEN HYSYS conceptual process simulation model; the composition of hydrogen rich gas (0.62% H₂O, 38.83% H₂, 1.65% CO, 26.13% CO₂, 0.08% CH₄, and 32.69% N₂) has been determined. The first simulation results show that the hydrogen purity of the product gas after PSA unit is 99.999% approximately. The mass lower heating value (LHV_mass) of the product gas before PSA unit is expected to be about 4500 kJ/kg and the overall fuel processor efficiency has been calculated as ～93%.     

超临界水中生物质气化制氢的反应路径

超临界水中生物质气化制氢技术因其具有良好的环保性、产氢高等特点已成为氢能领域的研究热点之一。文中对超临界水中生物质气化制氢反应路径的研究结果进行了总结，归纳了生物质及其模型化合物葡萄糖在亚临界和超临界水中分解气化的可能的反应路径以及反应过程中产生的一系列中间产物，讨论了影响反应的主要因素。     

Performance investigation of hydrogen production from a hybrid wind-PV system

In this study, a hybrid system consisted of 10 kW wind and 1 kWp PV array is built to meet the load demand of a raise chucker partridge raising facility by renewable energy sources. The facility has an average energy consumption of about 20.33 kWh/day, with a peak demand of 2.4 kW. The solar radiation data and wind data of the region are analyzed for sizing of the renewable energy system. The performance of each alternative system is examined in terms of energy efficiency, and H₂ production capacity of the hybrid system from due to excessive electrical energy is studied. A Matlab-Simulink Software is used for analyzing the system performance. The average range of state of charge varies between 56.6% and 88.3% monthly from April to July. The amount of hydrogen production by excess electricity is 14.4 kg in the month of July, due to the high wind speed and solar radiation. Energy efficiency of the electrolyser is found to be varying between 64% and 70% percent. Energy efficiency of each hybrid system is calculated. The overall energy efficiency of wind-electrolyser system varies between 5% and 14% while the energy efficiency of PV-electrolyser system changes within a narrower range, as between 7.9% to and 8.5%, respectively.     

Future oil production in Brazil—Estimates based on a Hubbert model

This paper forecasts oil production in Brazil, according to the Hubbert model and different probabilities for adding reserves. It analyzes why the Hubbert model might be more appropriate to the Brazilian oil industry than that of Hotelling, as it implicitly emphasizes the impacts of information and depletion on the derivative over time of the accumulated discoveries. Brazil's oil production curves indicate production peaks with a time lag of more than 15 years, depending on the certainty (degree of information) associated with the reserves. Reserves with 75% certainty peak at 3.27 Mbpd in 2020, while reserves with 50% certainty peak at 3.28 Mbpd in 2028, and with 30% certainty peak at 3.88 Mbpd in 2036. These findings show that Brazil oil industry is in a stage where the positive impacts of information on expanding reserves (mainly through discoveries) may outstrip the negative impacts of depletion. The still limited number of wells drilled by accumulated discoveries also explain this assertion. Being a characteristic of frontier areas such as Brazil, this indicates the need for ongoing exploratory efforts.     

An economic assessment of the use of short-rotation coppice woody biomass to heat greenhouses in southern Canada

This study explores the economic feasibility of fossil fuel substitution with biomass from short-rotation willow plantations as an option for greenhouse heating in southern Ontario, Canada. We assess the net displacement value of fossil fuel biomass combustion systems with an integrated purpose-grown biomass production enterprise. Key project parameters include greenhouse size, heating requirements, boiler capital costs and biomass establishment and management costs. Several metrics have been used to examine feasibility including net present value, internal rate of return, payback period, and the minimum or break-even prices for natural gas and heating oil for which the biomass substitution operations become financially attractive. Depending on certain key assumptions, internal rates of return ranged from 11-14% for displacing heating oil to 0-4% for displacing natural gas with woody biomass. The biomass heating projects have payback periods of 10 to >22 years for substituting heating oil and 18 to >22 years for replacing a natural gas. Sensitivity analyses indicate that fossil fuel price and efficiency of the boiler heating system are critical elements in the analyses and research on methods to improve growth and yield and reduce silviculture costs could have a large beneficial impact on the feasibility of this type of bioenergy enterprise.     

Energetic and economic evaluation of a poplar cultivation for the biomass production in Italy

The cultivation of crops for biomass production on good soils allows to reduce surplus production of food crops and increase the sustainability of energy production from the environmental point of view. The short rotation forestry (SRF), is only at a preliminary study level in Italy but, is already a reality in North Europe where was already developed an high planting density (6000–8000 cuttings ha^-1) technique and a whole mechanization of plantation and biomass harvest.On the basis of this cultivation technique, it was realized as an energetic and economic evaluation of a poplar SRF in Northern Italy. In detail, they were considered data of poplar growth in a plantation for the production of two-year whips in Western Po Valley considering SRF duration of 8 years and a biomass (20 t ha⁻¹ D.M.) harvest every 2 years. Indeed it was assumed to operate on a plantation in production (12.5% of the surface replanted every year) with a spacing 3.00 × 0.4 m (6700 cutting per hectare) that allows the use of conventional tractors.In this computing system it was pointed out a ratio between output and input energy of 13 and a cost of 80 € t⁻¹ of D.M. Nevertheless a positive energetic balance, the economic sustainability of poplar SRF depends, due to the present monopolistic energy management in the same countries, on political choices of chip price or public subventions to the producers.