Application of NIR Reflectance Spectroscopy on Rapid Determination of Moisture Content of Wood Pellets

NIR spectroscopy was used to measure the moisture concentration of wood pellets. Pellets were conditioned to various moisture levels between 0.63% and 14.16% (wet basis) and the moisture concentration was verified using a standard oven method. Samples from various moisture levels were separated into two groups, as calibration and validation sets. NIR absorption spectral data from 400 nm to 2500 nm with 0.5 nm intervals were collected using pellets within the calibration and validation sample sets. Spectral wavelength ranges were taken as independent variables and the MC of the pellets as the dependent variable for the analysis. Measurements were obtained on 30 replicates within each moisture level. Partial Least Square (PLS) analysis was performed on both raw and preprocessed spectral data of calibration set to determine the best calibration model based on Standard Error of Calibration (SEC) and coefficient of multiple determinations (R2). The PLS model that yielded the best fit was used to predict the moisture concentration of validation group pellets. Relative Percent Deviation (RPD) and Standard Error of Prediction (SEP) were calculated to validate goodness of fit of the prediction model. Baseline and Multiple Scatter Corrected (MSC) reflectance spectra with 1st derivative model gave the highest RPD value of 4.46 and R2 of 0.95. Also it’s SEP (0.670) and RMSEP (0.782) were less than the other models those had RPD value more than 3.0 with less number of factors. Therefore, this model was selected as the best model for moisture content prediction of wood pellets.

Upgraded Pellet Making by Torrefaction—Torrefaction of Japanese Wood Pellets

Upgraded wood pellets were produced and evaluated by torrefaction of wood pellets. In this study, conventional wood pellets were initially prepared and subsequently torrefied on a laboratory and then larger scale. During the laboratory scale production, pellets from wooden parts of Japanese cedar (sugi, Cryptomeria japonica) and Japanese oak (konara, Quercus serrata) trees were heat- treated in an inert gas oven under nitrogen atmosphere around 170°C - 320°C. For the Japanese cedar, the calorific values were improved by heat treatment up to 260°C. By heat treatment at 240°C, the upgrade ratio of higher heating value (HHV) was nearly 30% and the energy yield was 97%. For the Japanese oak, the calorific values were improved by heat treatment up to 320°C. By heat treatment at 280°C, the upgrade ratio of HHV exceeded 30% and the energy yield was 84%. On a larger scale, a conventional charcoal oven was modified for torrefied wood pellet production, meaning that torrefied wood pellet with 25 MJ/kg of calorific value was produced during heat treatment at 350°C. A mixture of conventional and torrefied pellets was applied to a commercial pellet stove, and torrefied wood pellets produced in this study might be usable as fuel for conventional pellet stoves.

Wood Pellet Co-Firing for Electric Generation Source of Income for Forest Based Low Income Communities in Alabama

Alabama imports coal from other states to generate electricity. This paper assessed the direct and indirect economic impacts of wood pellet production to be co-fired with coal for power generation in Alabama. Four sizes of wood pellet plants and regional input-output models were used for the analysis. The results showed that the economic impact increases with the size of the plant. Wood pellet production will have a multiplier effect on the economy especially, forest-related services, retail stores, the health service industry, and tax revenue for the government. Domestic wood pellet production can reduce the use of imported coal, allow the use of local woody biomass, and create economic activities in Alabama’s rural communities. Policies that support the production of wood pellet will serve to encourage the use of wood for power generation and support the rural economies.

Development and Evaluation of an All Weather-Type Solar Drying House to Make for Wood Pellet Material

To suppress the global environment pollutions, we tried to develop a new-type solar drying house by improving a typical agricultural green-house, so that an all weather-type solar drying house was invented ultimately. This house is capable to dry raw wood materials (Ogako) into suitable moisture content (Mc) to make a wood pellet. The all weather-type solar Ogako drying house is covered with a triple transparent film, and an open/close free-type shield sheet is spread along with house’s inner surface with a small space, which is opened when solar radiation is incident on the house in daytime and closed to prevent heat loss from the house while out of sun shining in night. Inside of the all weather-type solar Ogako drying house, there are four belt-conveyors over which four top radiation panels are hanged, and on which four Ogako agitators are touched, a turn-table, two hoppers, four small fans, and besides, a floor heating is molded in concrete floor. Also on the north wall outside the house, two insulated cylinders (chimney) are stood up vertically to exhaust inside moist air passively. Then, to make clearly the operation performance of the house, the drying tests for the proof examination were conducted nineteen times at first test site in Ashoro where is located east-central part of Hokkaido, Japan. As a result of the drying test for the proof examination, it was made clear that the all weather-type solar Ogako drying house is practically useful as a supplementary apparatus to produce the dried Ogako, and consequently to suppress CO2 exhaustion.

Fundamental Study on the Production of ＂Hyper Wood Pellet＂——Effect of Torrefaction Condition on Grinding and Pelletizing Properties

In order to upgrade the conventional wood pellet, Japanese softwood and hardwood chips were torrefied at around 200-350℃, and pelletized. The characteristics of the torrefied material/pellets such as their calorific value, grinding energy, pelletizing energy and elemental composition, were also evaluated in this study. The calorific value rose with increasing torrefaction temperature and exceeded 25 MJ/kg （an increase of nearly 40% compared to the untreated state） for torrefaction at around 350℃. The grinding energy greatly decreased with increasing torrefaction temperature, and the reduction was larger for Japanese oak hardwood chips. The pelletization energy for the torrefied material tended to be slightly smaller than in the untreated case. People named such torrefied pellet as ＂hyper wood pellet＂.

Quality Characteristics and Radioactive Contamination of Wood Pellet Imported in Italy

The problem of Caesium-137 (137 Cs) contamination of the imported wood pellet used for burning has been reported in Italy since June 2009. Since then, sampling and analysis were performed at the crossing border points of the provinces of Trieste and Gorizia, on request of the Health and Customs Border Bureau. This paper presents the results of the analysis performed on 65 samples from August 2010 to March 2012, which covered a total of products over 1500 tons of various origins, imported from Eastern Europe and the Balkans. Most of the samples showed very low 137 Cs activity concentrations;only a few hot spots showed 137 Cs activity concentrations higher than 100 Bq·kg-1. The results of dose evaluations for wood pellet stoves users under the hypotheses assumed in this study were largely below the threshold of radiological relevance.

Environmental and Economic Assessment of Wood Pellet Production from Trees in Greece

Biomass is a renewable, economic and readily available resource of energy that has potential to substitute fossil fuels in many applications such as heat, electricity and biofuels. The increased use of the agricultural biomass can help the agricultural based societies in achieving energy security and creating employment without causing environmental degradation. However, the viability and feasibility of electricity generation from agricultural biomass depends upon the availability of biomass supply at a competitive cost. The present study investigates the availability of agricultural biomass for distributed power generation in Greece (Kozani). The study concludes with a discussion on significance and challenges of decentralized electricity generation for rural energy supply, including brief description about economical, social, environmental and technical aspects of bioelectricity. With the application of the life cycle analysis applied, the environmental and economic impacts that will occur in the region of Kozani in Greece, where a biomass wood pellets production workshop is operating, have been assessed. The total annual emission of CO 657.9 gr, HC 22.36 gr, PM 67.94 and NOx 8.832,2 gr was calculated. The economic evaluation estimated the payback period for the investment in this plant to be approximately 3 years.

Fuelling and Diagnostics with Pellet Injection in the HL-1M Tokamak

The pellet injection experiments for fuelling and diagnostics have been carried out on the HL-1M tokamak. The eight-pellet injector was installed on HL-1M. A reliable monitordetector and camera system was set up to take initial pellet photographs and measure the initial pellet speed and size. High fuelling efficiency of 60 % - 100 % and a density profile with a peaking factor of 1.8 - 2.0 were obtained. The maximum density close to 10^14/cm^3 in HL-1M was achieved with newly optimized combined fuelling techniques. Two typical models of pellet ablation have been utilized for simulative calculation of the ablation rates in HL-1M. In comparison with the distribution of the measured Hα emission intensity from the digital data of the CCD camera, the experimental result seems more optimistic for core fuelling than theoretical predictions by the two models. The safety factor profile q（r） has been extracted from the information provided by the CCD camera during the pellet injection. The reliability of the measured results depends mainly on the calibration of the imaging space position. Based on the calibration, the measured q-profile becomes more reasonable than those published previously for the same shot number and same photograph.

Effect of Pelletized Graphite Addition on Properties of Al_2O_3-SiC-C Castables

Al2O3 - SiC - C castables with pelletized graphite addition of 0. 2%, 4% or 6% （by mass, the same hereinafter ） were prepared using brown fused corundum （8 - 5, 5 - 3 and 3 - 1 mm ） , dense fused corundum （ ≤1 and 0. 045 mm） and SiC （ ≤1 and ≤0. 064 mm） its main starting materials with mass ratio of aggregate： matrix = 71： 29, 2% silicon powder and 0. 4% B4C as antioxidants, and pelletized graphite as carbon source, Effect of pelletized graphite addition on physical properties, oxidation resistance, slag resistance arid thermal shock resistance of Al2O3 -SiC- C eastables was researched. The results show that： with the in.crease of pelletized graphite addition, the required water amount of castables increases, the bulk density and strength reduce; with 4% pelletized graphite, the eastable performs the best oxidation resistance; the increase of graphite is beneficial to the improvement of slag penetration resistance and corrosion resistance; with 6% pelletized graphite, the thermal shock resistance is the best.

5-氨基酮戊酸光动力诊断在男性生殖器尖锐湿疣中的应用

目的:探讨5-氨基酮戊酸光动力诊断(ALA-PDD)在男性生殖器尖锐湿疣的临床价值。方法:对113例男性生殖器尖锐湿疣患者先后分别给予醋酸白试验和ALA-PDD检查,即分为醋酸白组和ALA组,观察两组阳性率。结果:疣体及疣体周围ALA组阳性率均高于醋酸白组;两组差异有统计学意义(P<0.05)。结论:ALA-PDD诊断男性生殖器尖锐湿疣及亚临床潜伏感染有一定意义,值得临床推广。

木煤-极具发展潜力的新型能源

木质颗粒燃料是一种可再生、清洁和成本稳定的燃料,可由农作物秸秆、竹加工剩余物及普通的废旧木料等可再生的物质制成,北美和欧洲正在大量使用。主要介绍木质颗粒燃料产业的发展现状、产品特点、用途和制造工艺,并分析这种燃料在我国的发展前景。

木质颗粒燃料--可再生的清洁能源

木质颗粒燃料是一种可再生、清洁和成本稳定的燃料,可由农作物秸秆、木、竹加工剩余物及普通的废旧木料等可再生的物质制成,北美和欧洲正在大量使用。本文介绍了木质颗粒燃料产业的发展现状,产品特点、用途和制造工艺,并分析了这种燃料在我国的发展前景。

Cost of non-renewable energy in production of wood pellets in China

Assessing the extent to which all bio-fuels that are claimed to be renewable are in fact renewable is essential because producing such renewable fuels itself requires some amount of non-renewable energy （NE） and materials. Using hybrid life cycle analysis （LCA）--from raw material collection to delivery of pellets to end users--the energy cost of wood pellet production in China was estimated at 1.35 J/J, of which only 0.09 J was derived from NE, indicating that only 0.09 J of NE is required to deliver 1 J of renewable energy into society and showing that the process is truly renewable. Most of the NE was consumed during the conversion process （46.21%） and delivery of pellets to end users （40.69%）, during which electricity and diesel are the two major forms of NE used, respectively. Sensitivity analysis showed that the distance over which the pellets are transported affects the cost of NE significantly. Therefore the location of the terminal market and the site where wood resources are available are crucial to saving diesel.

Life cycle cost and economic assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario, Canada

Background： Replacement of fossil fuel based energy with biochar-based bioenergy production can help reduce greenhouse gas emissions while mitigating the adverse impacts of climate change and global warming. However, the production of biochar-based bioenergy depends on a sustainable supply of biomass. Although, Northwestern Ontario has a rich and sustainable supply of woody biomass, a comprehensive life cycle cost and economic assessment of biochar-based bioenergy production technology has not been done so far in the region. Methods： In this paper, we conducted a thorough life cycle cost assessment （LCCA） of biochar-based bioenergy production and its land application under four different scenarios： 1） biochar production with low feedstock availability; 2） biochar production with high feedstock availability; 3） biochar production with low feedstock availability and its land application; and 4） biochar production with high feedstock availability and its land applicationusing SimaPro, EIOLCA software and spreadsheet modeling. Based on the LCCA results, we further conducted an economic assessment for the break-even and viability of this technology over the project period. Results： It was found that the economic viability of biochar-based bioenergy production system within the life cycle analysis system boundary based on study assumptions is directly dependent on costs of pyrolysis, feedstock processing （drying, grinding and pelletization） and collection on site and the value of total carbon offset provided by the system. Sensitivity analysis of transportation distance and different values of C offset showed that the system is profitable in case of high biomass availability within 200 km and when the cost of carbon sequestration exceeds CAD S60 per tonne of equivalent carbon （CO2e）. Conclusions： Biochar-based bioenergy system is economically viable when life cycle costs and environmental assumptions are accounted for. This study provides a medium scale slow-pyrolysis plant scenario and we recommend similar experiments with large-scale plants in order to implement the technology at industrial scale.

Two-dimensional CFD simulation and pilot-scale experimental verification of a downdraft gasifier: effect of reactor aspect ratios on temperature and syngas composition during gasification

This paper focuses on a two-dimensional CFD simulation of a downdraft gasifier and a pilot-scale experiment for verification using wood pellet fuel.The simulation work was carried out via the ANSYS-Fluent CFD software package with in-house coding via User Defined Function.Three gasification parameters were taken into account in the simulation and validation to achieve highly accurate results;namely,fuel consumption,temperature profile,and syngas composition.After verification of the developed model,the effects of aspect ratios on temperature and syngas composition were investigated.Results from simulation and experimental work indicated that the fuel consumption rate during the steady state gasification experiment was 1.750±0.048 g/s.The average steady state temperature of the experiment was 1240.32±14.20 K.In sum,the fuel consumption and temperature profile during gasification from modeling and experimentation show an error lower than 1.3%.Concentrations of CO,CO2,H2,and CH4 were 20.42 vol%,15.09 vol%,8.02 vol%,and 2.6 vol%,respectively,which are comparable to those of the experiment:20.00 vol%,15.48 vol%,8.00 vol%,and 2.65 vol%.A high concentration of syngas is observed in the outer radial part of the reactor because of the resistive flow of the air inlet and the synthesis gas produced.The average temperatures during the steady state of the gasifier with aspect ratios(H/D)of 1.00,1.38(experiment),and 1.82 were 978.77±11.60,1256.46±9.90,and 1368.94±9.20 K,respectively.The 1.82 aspect ratio reactor has the smallest diameter,therefore the radiative heat transferred from the reactor wall affects the temperature in the reactor.Syngas compositions are comparable.Inverse relationships between the aspect ratios and the syngas LHV,(4.29–4.49 MJ/N m3),cold gas efficiency(29.66%to 31.00%),and carbon conversion(79.59%to 80.87%)are observed.

Large-scale transportation and storage of wood pellets:Investigation of the change in physical properties

The change in physical properties of wood pellets,with a focus on particle size distributions due to pellet breakage and attrition,was studied in a large-scale(∼450 ton/h)transportation system.Critical locations with a high probability of breakage through the whole transportation system were chosen and sampled to study the effect of transportation system design and operation on the mechanical properties of pellets.Bulk density,mechanical durability,moisture content,and particle size distribution of pellets were characterized for each sample.Analysis of variance showed that there were significant differences between the percentages of small particles(<5.6 mm)in the samples taken at different locations,especially at one with a vertical free fall of 7.8 m.On average,this relatively long drop increased the proportion of particles<5.6 mm in the samples from 8.73%to 14.09%,and that of particles<3.15 mm from 4.82%to 9.01%.Moreover,the measurements showed a wide deviation in the mechanical durability values,between a minimum of 90.8%and a maximum of 98.7%,which were not correlated to the sampling points but related to pellet properties.It can be concluded that pellet transportation systems require more dedicated design strategies to prevent breakage and attrition.

GC/FT-IR Analysis of Novel 4,6,9-Triene and 2,4,6,9-Tetraene Occurring in a Female Pheromone Gland of <i>Arctia plantaginis</i>(Erebidae: Arctiinae)

Fifteen subspecies of the wood tiger moth, Arctia plantaginis (Lepidoptera: Erebidae: Arctiinae), have been recorded in the Northern Hemisphere. An analysis of crude pheromone extracts by GC equipped with an electroantennographic (EAG) detector showed four EAG-active components (Comps. I–IV) that were commonly involved in the pheromone glands of two subspecies inhabiting Japan and Finland. Comp. I is a major component (>75%) and the others are minor components (3% - 15%). Their mass spectra, measured by GC/MS, revealed the chemical structures of C21 unsaturated hydrocarbons as follows: 3,6,9-triene for Comp. I, 4,6,9-triene for Comp. II, 1,3,6,9-tetraene for Comp. III, and 2,4,6,9-tetraene for Comp. IV. Comps. I and III are known Type II pheromone compounds, and their retention times coincide with those of the authentic standards with all Z configurations. As a next step, the extract was analyzed by GC/FT-IR to determine the configuration of Comps. II and IV. Their IR spectra showed two characteristic C-H bending absorptions around 990 and 945 cm-1 due to the conjugated dienyl moieties;thus, Z and E configurations were assigned to the double bonds at the 2- and 4-positions, respectively. Their Z double bonds at the 6- and 9-positions are indicated by no absorptions around 970 cm-1, due to the isolated double bonds with E configurations. Finally, the structures of Comps. II and IV were confirmed by synthesis using a double Wittig reaction. The synthetic (4E,6Z,9Z)-4,6,9-triene and (2Z,4E,6Z,9Z)-2,4,6,9-tetraene showed strong EAG activity, and their chemical data coincided well with those of the natural Comps. II and IV, indicating the correctness of the structure determination by GC/FT-IR analysis and its usefulness for Type II pheromone compounds.

烟煤、杂木颗粒和油泥混燃特性的热重分析

为了研究烟煤、杂木颗粒和油泥的掺混燃烧特性,通过热重试验对三者的掺混燃料进行燃烧特性分析,利用FWO法对掺混燃料进行动力学分析。研究结果表明:烟煤燃烧过程主要为固定碳燃烧,杂木颗粒的燃烧过程更复杂、燃烧性能最好,其综合燃烧特性指数高达1.93×10^(-7);掺烧杂木颗粒可有效改善烟煤的燃烧性能,当烟煤和杂木颗粒以1∶4的质量比掺混燃烧时,掺混燃料的着火温度较烟煤降低了35%,综合燃烧特性指数比杂木颗粒提高了7.2%;烟煤和杂木颗粒掺烧的最概然函数为[-ln(1-α)]^(-3)/4;当杂木颗粒掺混比高达45%时,适量掺混油泥有助于提升燃料燃烧性能;三者掺混燃料的燃烧反应最概然函数为[-ln(1-α)]2;当烟煤、杂木颗粒和油泥的掺混比例为40∶40∶20和45∶45∶10时,掺混燃料对应的活化能较其它比例掺混燃料有明显降低,综合燃烧特性指数是纯烟煤的1.5倍左右。

Energy analysis of a wood or pellet stove in a single-family house equipped with gas boiler and radiators

In the residential sector,biomass appliances are widely used for space heating and often combined with other systems.This work aims at comparing the final and primary energy consumption of different configurations,including a conventional and a ducted pellet stove and a wood log stove using air as heat transfer fluid.A dynamic analysis of the interaction between biomass stoves and conventional heating systems,such as gas boilers and radiators,is carried out within a typical single-family house in a mild climate,using TRNSYS software.In addition,natural ventilation of the building is considered using CONTAM,with a focus on external infiltrations and internal air circulation due to the buoyancy effect.Results show that the biomass device in one room promotes the airflows between adjacent thermal zones,enhancing the heat distribution through door openings,in particular when an air ducted stove is present.The final energy consumption resulting from simulations with wood-burning stoves is 21%higher than pellet stoves.The pellet stove results in similar final energy and a 30%increase in overall primary energy,while the wood stove increases the final energy by 22%and approximately 40%of overall primary energy compared to the case of a traditional gas system coupled to radiators which is considered as reference.Nevertheless,non-renewable primary energy savings are higher than 50%with pellet stoves and 60%with wood-log stoves.

木质颗粒燃料锅炉替代燃油燃气锅炉效益分析

为探讨木质颗粒燃料应用的效益,该文通过对比分析常规能源和木质颗粒燃料的单位能价及典型锅炉实际运行成本,在民用、工业锅炉领域,木质颗粒燃料的综合运行成本为燃油的32.95%、燃气的67.41%,仅替代现有燃油热水锅炉拥有量的1%,每年将节约运行费用60亿元,替代等量燃气锅炉每年将节约14.25亿元,并且将减排温室气体(CO2)440万t。在环保要求高的大中城市或者旅游区,推广这种木质颗粒燃料,将产生巨大的经济效益和环保效益。