Compression Characteristics of Selected Ground Agricultural Biomass

Agricultural biomass such as barley, canola, oat and wheat straw has the potential to be used as feedstock for bioenergy. However, the low bulk density straw must be processed and densified in order to facilitate handling, storage and transportation. It is important to understand the fundamental mechanism of the biomass compression process, which is required in the design of energy efficient compaction equipment to mitigate the cost of pre-processing and transportation of the product. Therefore, a comprehensive review of various compression models was performed and the compression behavior of selected ground agricultural biomass was studied. Five compression models were considered to determine the pressure-volume and pressure-density relationship to analyze the compression characteristics of biomass samples, namely: Jones (1960), Heckle (1961), Cooper-Eaton (1962), Kawakita-Ludde (1971) and Panelli-Filho (2001) models. Densification studies were conducted on four selected biomass samples at 10 % moisture content (w.b.) and 1.98 mm grind size using four pressure levels of 31.6, 63.2, 94.7 and 138.9 MPa. The mean densities of barley, canola, oat and wheat straw increased from 907 to 977 kg/m3, 823 to 1003 kg/m3, 849 to 1011 kg/m3 and 813 to 924 kg/m3, respectively. The Kawakita-Ludde model provided an excellent fit having R2 values of 0.99 for selected agricultural straw samples. It was also concluded that the ground oat and canola straw had the highest level of porosity and failure stress, respectively. The parameters of Cooper-Eaton model indicated that the ground straw samples were densified easily by the particles rearrangement method and Jones model indicated that canola and oat straw were more compressible as compared to barley and wheat straw

Antioxidants Classification and Applications in Lubricants

Oxidation is a chemical reaction that occurs in lubricants upon exposure to an oxidizing agent such as oxygen and can be catalyzed by copper and iron. Antioxidants are a group of chemicals that can be used in the formulation of lubricants to stop or reduce the rate of oxidation. Based on the mechanism of action, antioxidants are categorized as primary antioxidants (radical scavengers), secondary antioxidants (Peroxide decomposers), and metal deactivators (complex-forming or chelating agents). Selection of the antioxidants in a formulation is a critical decision that depends on the base oil, application and other ingredients in the formulations. Presence of some other ingredients in the product with antagonistic behavior may suppress the role of antioxidants; however, optimal application of antioxidants with synergistic behavior would increase the stabilization impact of the ingredients on the base oil

Potential Applications of Infrared and Raman Spectromicroscopy for Agricultural Biomass

The low bulk density agricultural biomass should be processed and densified making it suitable for biorefineries. However, many agricultural biomass (lignocellulosic) especially those from straw and stover results in poorly formed pellets or compacts that are more often dusty, difficult to handle and costly to manufacture. The binding characteristics of biomass can be enhanced by modifying the structure of lignocellulose matrix (cellulose-hemicellulose-lignin) by different pre-processing and pre-treatment methods. However, it is not well understood as to how various pre-processing and pre-treatment methods affect the lignocellulosic matrix at the molecular level. Therefore, it is essential to determine chemical composition of agricultural biomass and the distribution of lignin relative to cellulose and hemicellulose before and after application of various treatment methods and after densification process. In this paper, the structural characteristics of lignocellulosic plant biomass and applications of Infrared (IR) and Raman spectromicroscopy methods are reviewed. The IR and Raman methods have good potential to determine the structural characteristics and distribution of chemical components in lignocellulosic biomass. Both methods have their own advantages and drawbacks, and should be used as complementary techniques

Pretreatment of Crop Residues by Application of Microwave Heating and Alkaline Solution for Biofuel Processing: A Review

The effect of microwave-assisted alkaline pretreatments and enzymatic saccharification of lignocellulosic agricultural crop residues are reviewed. Pretreatment is a major step for the efficient and effective biochemical conversion of lignocellulosic biomass to biofuel. Microwave-assisted alkali pretreatment is one of the promising techniques used in the bioconversion of biomass into useful energy product. The advantages of microwave heating coupled with alkaline pretreatment include reduction of the process energy requirement, rapid and super heating, and low toxic compound formation. This chapter reviews recent microwave-assisted alkali pretreatment and enzymatic saccharification techniques on different agricultural residues highlighting lignocellulosic biomass treatments and reducing sugar yields, and recovery. In addition, compiled up-to-date research studies, development efforts and research findings related to microwave-assisted alkali, and enzymatic hydrolysis are provided

Enzymatic Saccharification of Canola Straw and Oat Hull Subjected to Microwave-Assisted Alkali Pretreatment

Pretreatment of lignocellulosic biomass is a critical step in removing substrate-specific barriers to the cellulolytic enzyme attack. The study compared the effectiveness of microwave-assisted alkali pretreatment and alkali treatment in the enzymatic saccharification of canola straw and oat hull. Microwave pretreatments were employed by immersing the biomass in dilute alkali solutions (NaOH and KOH) at concentrations of 0, 0.75, and 1.5% (w/v) for microwave-assisted heating times of 6, 12, and 18 min. Alkali treatments were carried out using the same procedure but by soaking and without microwave heating. The highest glucose yields after enzymatic saccharification of both canola straw and oat hull were obtained when these feedstocks were ground using 1.6 mm hammer mill screen size and subjected to microwave-assisted alkali pretreatment using 1.5% and 0.75% NaOH for 18 min, respectively. SEM analysis indicated a more significant modification in the structure of biomass samples subjected to microwave-assisted alkali pretreatment compared to untreated and alkali-treated biomass samples. Results indicated that microwave-assisted alkali pretreatment with short residence time is effective in improving the glucose yield of canola straw and oat hull during enzymatic saccharification

Modeling the microbial pretreatment of camelina straw and switchgrass by Trametes versicolor and Phanerochaete chrysosporium via solid-state fermentation process: A growth kinetic sub-model in the context of biomass-based biorefineries

Advancing microbial pretreatment of lignocellulose has the potential not only to reduce the carbon footprint and environmental impacts of the pretreatment processes from cradle-to-grave, but also increase biomass valorization, support agricultural growers, and boost the bioeconomy. Mathematical modeling of microbial pretreatment of lignocellulose provides insights into the metabolic activities of the microorganisms as responses to substrate and environment and provides baseline targets for the design, development, and optimization of solid-state-fermentation (SSF) bioreactors, including substrate concentrations, heat and mass transfer. In this study, the growth of Trametes versicolor 52J (TV52J), Trametes versicolor m4D (TVm4D), and Phanerochaete chrysosporium (PC) on camelina straw (CS) and switchgrass (SG) during an SSF process was examined. While TV52J illustrated the highest specific growth rate and maximum cell concentration, a mutant strain deficient in cellulose catabolism, TVm4D, performed best in terms of holocellulose preservation and delignification. The hybrid logistic-Monod equation along with holocellulose consumption and delignification models described well the growth kinetics. The oxygen uptake rate and carbon dioxide production rate were directly correlated to the fungal biomass concentration; however, a more sophisticated non-linear relationship might explain those correlations better than a linear model. This study provides an informative baseline for developing SSF systems to integrate fungal pretreatment into a large-scale, on-farm, wet-storage process for the utilization of agricultural residues as feedstocks for biofuel production

Modified Biopolymer Adsorbents for Column Treatment of Sulfate Species in Saline Aquifers

In the present study, variable forms of pelletized chitosan adsorbents were prepared and their sulfate uptake properties in aqueous solution was studied in a fixed-bed column system. Unmodified chitosan pellets (CP), cross-linked chitosan pellets with glutaraldehyde (CL–CP), and calcium-doped forms of these pellets (Ca–CP, Ca–CL–CP) were prepared, where the removal efficiencies and breakthrough curves were studied. Dynamic adsorption experiments were conducted at pH 4.5 and 6.5 with a specific flow rate of 3 mL/min, fixed-bed height of 200 mm, and an initial sulfate concentration of 1000 mg/L. Breakthrough parameters demonstrated that Ca–CP had the best sulfate removal among the adsorbents, where the following adsorption parameters were obtained: breakthrough time (75 min), exhaust time (300 min), maximum sulfate adsorption capacity (qmax; 46.6 mg/g), and sulfate removal (57%) at pH 4.5. Two well-known kinetic adsorption models, Thomas and Yoon-Nelson, were fitted to the experimental kinetic data to characterize the breakthrough curves. The fixed-bed column experimental results were well-fitted by both models and the maximum adsorption capacity (46.9 mg/g) obtained was for the Ca–CP adsorbent. A regeneration study over four adsorption-desorption cycles suggested that Ca–CP is a promising adsorbent for sulfate removal in a fixed-bed column system

Dust and Particulate Matter Generated during Handling and Pelletization of Herbaceous Biomass: A Review

Using straw and herbaceous crops to replace or augment fossil fuels is becoming popular as access to forest biomass becomes environmentally stricter and more expensive. The low bulk density raw biomass is pre-processed and densified into pellets to facilitate handling and use. Dust is generated during collection, baling and debaling, grinding, drying, and densifying processed herbaceous biomass. Abundant literature deals with dust generated during the industrial handling of woody biomass, grains, and other crops like cotton. But the information on handling herbaceous biomass in the open literature is scarce. This paper reviews the available literature on dust generation from handling and processing of herbaceous biomass. Limited available data shows that herbaceous biomass species have a lower ignition temperature than woody biomass. The paper identifies several crucial pieces of information needed to ensure safety in the handling and pelleting of herbaceous crops.Applied Science, Faculty ofNon UBCChemical and Biological Engineering, Department ofReviewedFacult

Actualization and Adoption of Renewable Energy Usage in Remote Communities in Canada by 2050: A Review

Remote community initiatives for renewable energy are rapidly emerging across Canada but with varying numbers, success rates, and strategies. To meet low-carbon transition goals, the need to coordinate technology deployment and long-term policy to guide the adoption is critical. Renewable resources such as wind, solar, hydro, and biomass can provide energy at a subsidized cost, create sustainable infrastructure, and provide new economic viability in social value integration. The renewable energy transition is crucial to Canada in sustaining remote and indigenous communities by providing local, clean, and low-carbon-emission energy for heat, power, and possibly transportation. This paper identified 635 renewable resources projects deployed to improve and increase electricity supply. To an extent, balancing demand within the remote and indigenous communities of Canada and highlighting sustainable renewable energy development through ownership participation within the communities is achievable before 2050 and beyond through energy efficiency and the social value of energy. The article identifies clean energy targets as mandated by the different provinces in Canada to reach net-zero GHG emissions