scholarly journals Effect of Moisture on Gas Emissions from Stored Woody Biomass

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 128 ◽  
Author(s):  
Xiao He ◽  
Anthony K. Lau ◽  
Shahab Sokhansanj
Keyword(s):  
Moisture Content ◽  
Dry Matter ◽  
Dry Mass ◽  
Decay Resistance ◽  
Slight Reduction ◽  
Gas Emissions ◽  
Aerobic Conditions ◽  
Red Cedar ◽  
Order Of Magnitude ◽  
Effect Of Moisture

Biomass materials have been increasingly used due to their renewable nature. The problems occurring during the storage of fresh woody materials include gas emissions and dry matter losses as a result of degradation. The objective of this study was to investigate and quantify the effect of moisture content on gas emissions from stored wood chips. Experiments were conducted under non-aerobic and aerobic conditions using fresh Western Red Cedar (WRC) chips with different initial moisture contents over a range of temperatures. The peak CO2 emission factor of 2.9 g/kg dry matter (DM) was observed from high moisture chips at 20 °C under non-aerobic conditions after two-month storage, which was an order of magnitude greater than that from low moisture chips. In the case of volatile organic compounds, a range of compounds were detected from all tests. The concentration of VOCs was found to be positively correlated with moisture content. Gas emissions from the aerobic reactors exhibited similar trends as non-aerobic reactors with respect to the effect of moisture content, although higher values were observed under aerobic conditions. Slight reduction of dry mass from all tests at the end of storage indicated the decay-resistance characteristics of WRC.

scholarly journals Effect of Moisture Content on the Processing and Mechanical Properties of a Biodegradable Polyester

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1616
Author(s):  
Vincenzo Titone ◽  
Antonio Correnti ◽  
Francesco Paolo La Mantia
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Moisture Content ◽  
Mechanical Testing ◽  
Hydrolytic Degradation ◽  
Slight Reduction ◽  
Biodegradable Polyester ◽  
Molding Process ◽  
Elongation At Break ◽  
Effect Of Moisture

This work is focused on the influence of moisture content on the processing and mechanical properties of a biodegradable polyester used for applications in injection molding. The pellets of the biodegradable polyester were exposed under different relative humidity conditions at a constant temperature before being compression molded. The compression-molded specimens were again placed under the above conditions before the mechanical testing. With all these samples, it is possible to determine the effect of moisture content on the processing and mechanical properties separately, as well as the combined effect of moisture content on the mechanical properties. The results obtained showed that the amount of absorbed water—both before processing and before mechanical testing—causes an increase in elongation at break and a slight reduction of the elastic modulus and tensile strength. These changes have been associated with possible hydrolytic degradation during the compression molding process and, in particular, with the plasticizing action of the moisture absorbed by the specimens.

De-coupling seasonal changes in water content and dry matter to predict live conifer foliar moisture content

2014 ◽  
Vol 23 (4) ◽  
pp. 480 ◽  
Author(s):  
W. Matt Jolly ◽  
Ann M. Hadlow ◽  
Kathleen Huguet
Keyword(s):  
Water Stress ◽  
Moisture Content ◽  
Water Content ◽  
Seasonal Variations ◽  
Seasonal Changes ◽  
Dry Matter ◽  
Water Mass ◽  
Water Status ◽  
Dry Mass ◽  
Dry Matter Partitioning

Live foliar moisture content (LFMC) significantly influences wildland fire behaviour. However, characterising variations in LFMC is difficult because both foliar mass and dry mass can change throughout the season. Here we quantify the seasonal changes in both plant water status and dry matter partitioning. We collected new and old foliar samples from Pinus contorta for two growing seasons and quantified their LFMC, relative water content (RWC) and dry matter chemistry. LFMC quantifies the amount of water per unit fuel dry weight whereas RWC quantifies the amount of water in the fuel relative to how much water the fuel can hold at saturation. RWC is generally a better indicator of water stress than is LFMC. We separated water mass from dry mass for each sample and we attempted to best explain the seasonal variations in each using our measured physiochemical variables. We found that RWC explained 59% of variation in foliar water mass. Additionally, foliar starch, sugar and crude fat content explained 87% of the variation in seasonal dry mass changes. These two models combined explained 85% of the seasonal variations in LFMC. These results demonstrate that changes to dry matter exert a stronger control on seasonal LFMC dynamics than actual changes in water content, and they challenge the assumption that LFMC variations are strongly related to water stress. This methodology could be applied across a range of plant functional types to better understand the factors that drive seasonal changes in LFMC and live fuel flammability.

Effect of moisture content on anaerobic digestion of dewatered sludge: ammonia inhibition to carbohydrate removal and methane production

2000 ◽  
Vol 41 (3) ◽  
pp. 119-127 ◽  
Author(s):  
S. Fujishima ◽  
T. Miyahara ◽  
T. Noike
Keyword(s):  
Anaerobic Digestion ◽  
Moisture Content ◽  
Removal Efficiency ◽  
Methane Production ◽  
Ammonia Concentration ◽  
Methanogenic Bacteria ◽  
Order Of Magnitude ◽  
Vs Removal ◽  
Effect Of Moisture ◽  
Dewatered Sewage Sludge

The purpose of this study is to investigate the effect of moisture content on anaerobic digestion of dewatered sewage sludge under mesophilic condition. The moisture contents of sludge fed to reactors were 97.0%, 94.6%, 92.9%, 91.1% and 89.0%. The VS removal efficiency changed from 45.6% to 33.8%, as the moisture content of sludge fed to digester decreased from 97.0% to 89.0%. The carbohydrate removal efficiency also decreased from 71.1% to 27.8%. Methane production decreased when the moisture content of sludge was lower than 91.1%. The number of glucose consuming acidogenic bacteria was decreased from 3.1×106 to 3.1×108(MPN/mL) as the moisture content decreased from 91.1% to 89.0%. The numbers of hydrogenotrophic and acetoclastic methanogenic bacteria decreased by one order of magnitude when the moisture content was lower than 91.1%. The decrease in numbers of glucose consuming acidogenic bacteria and methanogenic bacteria was found to correspond to the decrease in the carbohydrate removal efficiency and the accumulation of propionic acid. Batch experiments showed that acetoclastic methanogenic bacteria were acclimated to high ammonia concentration, on the other hand, glucose consuming acidogenic bacteria were inhibited.

Optimum harvest date of maize for biogas and silage purposes

2009 ◽  
Vol 57 (2) ◽  
pp. 119-125
Author(s):  
G. Hadi
Keyword(s):  
Dry Matter ◽  
Biogas Production ◽  
Weather Conditions ◽  
Vegetation Period ◽  
Dry Mass ◽  
Matter Content ◽  
Harvest Date ◽  
Dry Matter Content ◽  
Dry Matter Yield ◽  
Vegetative Organs

The dry matter and moisture contents of the aboveground vegetative organs and kernels of four maize hybrids were studied in Martonvásár at five harvest dates, with four replications per hybrid. The dry matter yield per hectare of the kernels and other plant organs were investigated in order to obtain data on the optimum date of harvest for the purposes of biogas and silage production.It was found that the dry mass of the aboveground vegetative organs, both individually and in total, did not increase after silking. During the last third of the ripening period, however, a significant reduction in the dry matter content was sometimes observed as a function of the length of the vegetation period. The data suggest that, with the exception of extreme weather conditions or an extremely long vegetation period, the maximum dry matter yield could be expected to range from 22–42%, depending on the vegetation period of the variety. The harvest date should be chosen to give a kernel moisture content of above 35% for biogas production and below 35% for silage production. In this phenophase most varieties mature when the stalks are still green, so it is unlikely that transport costs can be reduced by waiting for the vegetative mass to dry.

Nitrogen Fertilization of Basil

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 481a-481 ◽  
Author(s):  
M. Rangappa ◽  
H.L. Bhardwaj
Keyword(s):  
Moisture Content ◽  
Dry Matter ◽  
Calcium Nitrate ◽  
Control Treatment ◽  
Dry Matter Yield ◽  
Sweet Basil ◽  
Broad Leaf ◽  
Yield Difference ◽  
Optimum N Rate ◽  
N Rates

Sweet basil (Ocimum basilicum) is an important culinary herb in Virginia and other areas. The objective of this study, conducted during 1997, was to determine optimal N rate for fresh and dry matter yield. Seed of Broad Leaf sweet basil were direct-seeded on 18 June in rows 0.75 m apart in a RCBD design with 8 replications. Four N rates (0, 25, 50, and 75 kg N/ha) were used. Calcium nitrate (15.5% N) was used as the fertilizer source. All plants from 1-m row length from middle row of each plot were harvested by hand on 23 Sept. and fresh weights were recorded. The plant material was dried at 70°C for 48 h to record dry weights. The moisture content at harvest was calculated from fresh and dry weights. The fresh yields following 0, 25, 50, and 75 kg N/ha were 3.7, 5.4, 6.4, and 6.8 kg/m2, respectively. The yield difference between two highest N rates was not significant, however, both these rates had significantly higher yield than the two lowest rates. Similar results were also obtained for dry matter yields. The highest N rate of 75 kg N/ha resulted in significantly higher dry matter yield (1.3 kg/m2) as compared to the other three rates. The lowest dry matter yield was obtained after the control treatment (0.6 kg/m2). An opposite relationship between N rate and moisture content was observed when the highest moisture content resulted from control and 50 kg N/ha treatments. These results indicate that optimum N rate for sweet basil in Virginia is 50 to 75 kg/ha.

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