Types Of Agricultural Residues Research Articles

Efficacy of Agricultural Residue-Derived Biochar for Tackling Cadmium Contamination in an Aqueous Solution.

This study aimed to investigate the efficacy of biochar, produced from different agricultural residues varying in lignin and cellulose content and subjected to different pyrolysis temperatures, in removing cadmium ions (Cd (II)) from an aqueous solution. This removal process is crucial for protecting human health and the environment. Specifically, the study focused on the adsorption behaviors of Cd (II) by the biochars made from rice husk biochar (RHB), maize straw biochar (MSB), peanut shell biochar (PSB), cottonseed shell biochar (CHB), and mulberry leaf biochar (MLB), which were prepared at 300 °C and 600 °C. The results indicated that the type of agricultural residue used to produce biochar significantly influenced the adsorption of Cd (II). Notably, mulberry leaf biochar prepared at 300 °C (MLB-300) demonstrated the highest adsorption efficiency, achieving a maximum adsorption capacity of 42.2 mg g-1. Batch adsorption experiments assessed the impact of various factors, including system pH, NO3- concentration, and adsorption duration. The adsorption kinetics were better described by the pseudo-second-order model than the pseudo-first-order model. Moreover, the study found that the lignin content of the biochar plays a major role in determining the adsorption capacity. The surface characteristics of biochar, influenced by the types of agricultural residues and preparation temperature, directly impact its adsorption mechanism and capacity. While biochar produced at 300 °C showed optimal Cd(II) adsorption, those processed at 600 °C were less effective, likely due to the loss of functional groups at higher temperatures.

Physicochemical characterization, chemical composition and antioxidant activities of pyroligneous acids from cocktails of wood and agricultural residues from Ivory Coast

Physical, chemical characterization and antioxidant activities were assessed on six pyroligneous acids from four wood cocktails (WCV1, WCV2, WCV3, WCV4) and two types of agricultural residues (PA1, PA2) from Ivory Coast. Physical and chemical parameters of pyroligneous extracts were determined using a density meter, refractometer, pH meter, colorimetric titration, drying and sensory test. WCV2 alone simultaneously met all the standards set by the Japanese Pyroligneous Liquor Association, with a distinct smoky odour, a clear light-brown color, a pH of around 3, a density in the 1.010–1.020 g/mL range, and an ignition residue content of less than 0.2 %. In addition, WCV3, blackish in colour, had the highest Brix value (9) with a lower moisture content than the others (89.92 %), thus reflecting a high soluble tar content. Furthermore, all pyroligneous liquids had a high moisture content (89.92–99.08 %) and a low total acid content (0.90–2.10 %) compared with the literature. However, the results of GC-MS analysis revealed the presence of major compounds such as acetic acid, propionic acid, phenol, guaiacol and 3-methylphenol in the organic phase of pyroligneous extracts. FTIR analysis identified alkaloids, phenolic compounds and flavonoids in the aqueous phase of pyroligneous extracts. The presence of these compounds was confirmed by a phytochemical screening test. Finally, antioxidant activities with DPPH and ABTS methods showed that WCV2 had the best antioxidant properties due to its high guaiacol and syringol content. On the other hand, WCV3 showed a good antioxidant efficacy only by the DPPH method, probably due to its high flavonoid content.

Isolation and screening of biosurfactant producing yeast from soil contaminated with oil

The present study was aimed to isolate yeasts from soil samples contaminated with oil and their ability to produce biosurfactants. Five samples were collected from different sites of Baghdad, thirty four isolate of yeasts were obtained from these contaminated soil. Nineteen isolates from them were able to produce biosurfactant according to the diameter of clearing zonein solution test, while other isolates gave negative results. The yeast isolates which gave positive result werequantitatively screened on the basis of emulsification index and surface tension, secondary screening showed that isolates SD5, SB8 and SK10 giving the highest yield of biosurfactant in their cultures and the values of emulsification index were 45.7%, 56.9% and 53.4% respectively. Also, the biosurfactant of isolates SD5, SB8 and SK10 were exhibited maximum ability to reduce the surface tension of medium to 38.2, 27.1 and 30.8 mN\m respectively. Finally selected isolates SD5, SB8 and SK10 were identification on the basis of morphological and biochemical tests, the results revealed that isolates were identified as Saccharomyces cerevisiaeSB8, Candida glabrataSD5 and Candida glabrata SK10 respectively.The three most active isolates were tested to see their ability to produce biosurfactant in BH medium supplemented with four types of agricultural residues (rice bran, banana peel, wheat bran and corn cobs) as a source of carbon compared with BH medium with glucose. All isolates showed good ability to produce biosurfactant in liquid medium with different types of agricultural wastes and also with glucose. Candida glabrata SD5 exhibited highest activity for biosurfactant production when grown on agricultural wastes and glucose depend on the values of emulsification index and surface tension, whilethe wheat bran as a substrate gave best stimulation for biosurfactant production compared with other agricultural wastes.

A high spatial resolution dataset of China’s biomass resource potential

Assessing biomass resource potential is essential for China’s ambitious goals of carbon neutrality, rural revitalization, and poverty eradication. To fill the data gap of high spatial resolution biomass resources in China, this study estimates the biomass resource potential for all types of lignocellulosic biomass feedstock at 1 km resolution in 2018, including 9 types of agricultural residues, 11 types of forestry residues, and 5 types of energy crops. By combining the statistical accounting method and the GIS-based method, this study develops a transparent and comprehensive assessment framework, which is in accordance with the principle of food security, forest land and pasture protection, and biodiversity protection. In the end, we organize and store the data in different formats (GeoTIFF, NetCDF, and Excel) for GIS users, integrated modelers, and policymakers. The reliability of this high spatial resolution dataset has been proved by comparing the aggregated data at the subnational and national levels with the existing literature. This dataset has numerous potential uses and is a crucial input to many bioenergy-related studies.

Mercerization of Agricultural Waste: Sweet Clover, Buckwheat, and Rapeseed Straws

This research presents the alkali treatment effect on three types of agricultural residues: sweet clover (SCS), buckwheat (BS), and rapeseed straws (RS). The aim of the study was to find the optimal treatment conditions for each straw type, and to assess the potential of sweet clover straw as reinforcement for polymer composites in comparison to buckwheat and rapeseed. The straws were ground and treated for 15, 30, and 60 min using NaOH at concentrations of 2, 5, and 10%. To investigate the treatment results on the SCS, BS, and RS fibers, Fourier transform infrared spectroscopy, scanning electron microscopy, optical microscope, X-ray diffraction, and thermogravimetric analysis were used. Results indicate that the optimal room-temperature alkaline-treatment conditions of SCS fibers were the same as those for RS treated with 2% NaOH solution for 30 min. These conditions were milder in comparison to those used for the treatment of BS: 60 min in a 5% NaOH solution. During the treatment, noncellulosic substances were largely removed, and the aspect ratio of the fibers was increased, and the destruction temperature, crystallinity, and morphology were also affected. Consequently, SCS has promising potential for use in polymer composites.

Pyrolysis, kinetics, and structural analyses of agricultural residues in Egypt: For future assessment of their energy potential

Agricultural residues receive significant attention worldwide as a sustainable and green energy source. The accurate assessment of agricultural residues’ energy potential depends on physicochemical properties that change with location and climate. Several studies provide an imprecise estimation of agricultural residues’ energy potential in Egypt based on characteristics in literature from other sites. This study investigates the physicochemical properties, pyrolysis, and kinetics of seven types of agricultural residues, namely corn stalks, switchgrass, okra stems along with ficus, camphor, desert olive, and blueberry tree woodchips sampled from several locations in Egypt. The thermogravimetric, differential thermal, proximate, ultimate, lignocellulosic constituents, kinetics, crystallinity, and microstructure analyses are used to characterize the biomass. Kinetic parameters were determined by applying Coats-Redfern and Direct-Arrhenius approaches. The results revealed that woody residues have higher volatile matters, energy contents, hemicellulose, and lignin with lower ash, moisture, and cellulose than herbaceous residues. The activation energies of woody residues are lower than that of switchgrass and okra stems but higher than Cornstalks. The tested residues are bulk with nonuniform crystal structures, and their usages require further processing. The woody residues have promising properties. This study facilitates the accurate assessment of the agricultural residues’ energy potential in Egypt.

Demand and cost analysis of agricultural residues utilized as biorenewable fuels for power generation

This research aimed to develop a cost model in acquiring various agricultural residues as fuels for biomass power plants and to investigate cost differentiation when sources of biomass materials were changed or combined to produce electricity. Database of agricultural residues including location, availability and price throughout Thailand was accumulated based on top seven highest availability sources. Cost model was developed to compare cost when different types of agricultural residues were utilized to generate either electricity or heat. Cluster analysis was applied in the demand side analysis by clustering biomass power plants which were located within 50 km radius from the same centroid. Transportation cost was estimated from the biomass source to the corresponding demand centroid. The cost model for transporting agricultural residues to the demand location was then proposed. From the cost model of transporting agricultural residues, a biomass power plant was chosen as examples. It was shown that when the biomass power plant replaced eucalyptus barks with corncobs, the production cost could be reduced by more than 60%. From the analysis, it was also revealed that the most important factors that a biomass power plant should consider were energy content and cost of the raw material, as well as availability of the nearest supply source.

Progress on agricultural residue-based microwave absorber: a review and prospects

Microwave absorber comprising various agricultural residue-based microwave-absorbing materials is one of the interesting and challenging topics to modern-day scientists and engineers. In this work, we explicitly present an overview of the microwave absorption mechanism, different measurement techniques, various types of microwave absorber structure, and factors affecting the microwave absorption. We also discuss various stages of fabrication of lightweight and low-cost microwave absorber using different types of agricultural residues. This review provides an overall summary of the state-of-the-art progress on various agricultural residue-based microwave absorbers. Finally, some new prospects are also discussed from the existed theoretical and experimental results in this work, to propel their application in practice.

Thermochemical equilibrium study of ash transformation during combustion and gasification of sewage sludge mixtures with agricultural residues with focus on the phosphorus speciation

The necessity of recycling anthropogenically used phosphorus to prevent aquatic eutrophication and decrease the economic dependency on mined phosphate ores encouraged recent research to identify potential alternative resource pools. One of these resource pools is the ash derived from the thermochemical conversion of sewage sludge. This ash is rich in phosphorus, although most of it is chemically associated in a way where it is not plant available. The aim of this work was to identify the P recovery potential of ashes from sewage sludge co-conversion processes with two types of agricultural residues, namely wheat straw (rich in K and Si) and sunflower husks (rich in K), employing thermodynamic equilibrium calculations. The results indicate that both the melting behavior and the formation of plant available phosphates can be enhanced by using these fuel blends in comparison with pure sewage sludge. This enhanced bioavailability of phosphates was mostly due to the predicted formation of K-bearing phosphates in the mixtures instead of Ca/Fe/Al phosphates in the pure sewage sludge ash. According to the calculations, gasification conditions could increase the degree of slag formation and enhance the volatilization of K in comparison with combustion conditions. Furthermore, the possibility of precipitating phosphates from ash melts could be shown. It is emphasized that the results of this theoretical study represent an idealized system since in practice, non-equilibrium influences such as kinetic limitations and formation of amorphous structures may be significant. However, applicability of thermodynamic calculations in the prediction of molten and solid phases may still guide experimental research to investigate the actual phosphate formation in the future.

POTENTIAL AND PROSPECTS FOR USING AGRIBIOMASS FOR ENERGY IN UKRAINE

Purpose of the work is to identify promising directions for using agribiomass for energy in Ukraine. Current state and prospects for the development of this segment of bioenergy are considered. Analysis of the strategic goals for bioenergy development set by the National Renewable Energy Action Plan until 2020 and Energy Strategy of Ukraine until 2035 shows that only wide involvement of agribiomass in the country's fuel and energy complex can ensure attainment of these goals. Ukraine has considerable potential of agricultural biomass. According to data of 2018, it is 10.1 Mtoe, which is 44% of the total bioenergy potential. The main constituents of agribiomass potential are cereal straw and by-products of grain corn production. Today, of the various types of agribiomass, sunflower husk is most actively used for energy: more than 63% of its potential. Utilization of the potential of other types of agricultural residues is between 0 and 3%. For Ukraine, the most promising direction is priority use of corn stover for energy. Feasibility study of corn stalks harvesting as well as production of briquettes and pellets from them was performed. Main factors affecting the cost-effectiveness of projects on solid biofuel production are cost of raw materials, manufacturing line productivity and sale price of the finished product. Results of the feasibility study show that corn briquettes and pellets can be competitive in the biofuel market of Ukraine, and their production can be a profitable business project.

Common characteristics of feedstock stage in life cycle assessments of agricultural residue-based biofuels

In this study, we conducted life cycle assessments (LCAs) for fuels based on different types of agricultural residues and determined the characteristics common to all LCAs. Each fuel type required specific conversion technology during the feedstock stage, particularly during the production and collection processes. We divided the field-to-fuel life cycle into five high-level and relatively independent sub-stages: production of agricultural residues, collection of agricultural residues, conversion of agricultural residues to biofuels, biofuel distribution, and biofuel utilization. We then illustrated the common characteristics during the feedstock stage for the first two field-to-fuel life cycle sub-stages: production and collection of agricultural residues. Agricultural residues-to-grain weight and price ratios and multifactorial LCA allocations were summarized for the production stage. In addition, the energy use availability coefficient, collection radius, and emissions were determined for each fuel type during the collection stage. System boundaries and benefits of direct emissions reduction during the feedstock stage were also discussed. Our results provide guidance for future LCA studies on agricultural residue-based biofuels.

Assessing the Suitability of Biomass Ashes from Combustion in Boilers as Soil Fertilizers: Statistical Entropy Analysis and Introduction of the Potassium Utilization Potential Factor

Utilizing agricultural residues for energy and heating purposes is gaining momentum in the EU and even more in areas where biomass is a fundamental pillar of the economy like, e.g. South Tyrol in Northern Italy. In previous studies, the authors studied the combustion, in a commercial boiler of four different types of agricultural residues that were previously pelletized. This study has the scope to assess the suitability of the deriving biomass ashes as soil fertilizers. In this analysis potassium is identified as a key indicator for the nutrient content of biomass residue ashes. Therefore, this study introduces a new factor for assessing the utilization potential of biomass residues ashes, which is defined as the “potassium utilization potential factor” or KUP factor (with K representing potassium). The analysis is based on combining the initial concentration of potassium in the feedstock and the efficiency of statistical entropy. Statistical entropy analysis showed that combustion had a diverse substance concentrating efficiency of potassium for the four different types of biomass, ranging from 25 to 40%. In total, apple logs and apple pruning had the best performance in respect to their suitability as soil fertilizer since these feedstocks had the highest KUP factors.

Phosphorus Removal from Aqueous Solution by Pre- or Post-Modified Biochars Derived from Agricultural Residues

Biochar produced from agricultural residues through pyrolysis has the characteristics of large specific surface area and porous structure and thus can be used as an adsorbent for various contaminants. In this study, five types of agricultural residues, peanut shells (PS), mung bean shells (MBS), rice husk (RH), corn cob (CC), and cotton stalks (CS), were selected as feedstocks to prepare biochars. Magnesium chloride (MgCl2; 5 mol L−1 m) solution was used as a modifier to prepare pre-modified and post-modified biochar adsorbents. The modified biochars were used in adsorption experiment to test their sorption ability to phosphate from aqueous solution. Model simulations and analysis were used to determine phosphorus removal mechanisms. Experimental results showed that the phosphate removal efficiency of the pre-modified cotton stalk paralyzed at 600 °C (Pre-CS600) was the best with adsorption capacity of 129.9 mg g−1. The results also showed that the adsorption capacity of the biochar pre-modified by MgCl2 was much better than that of unmodified and post-modified ones, suggesting the pre-modification method can be used to prepare modified biochars for the removal of phosphorus from aqueous solution.

Determination and comparison of combustion kinetics parameters of agricultural biomass from olive trees

Thermogravimetric curves in air, measured for the different types of agricultural residues from olive trees (leaves, pruning and wood) at different heating rates (5, 10, 20, 40, 100 K/min), are subjected to kinetic evaluation by model-based and model-free methods. It is shown that the combustion process in the samples analyzed can be divided into three stages: water removal, roasting phase and char decomposition. At every stage, the activated energy varies with the mass conversion for the kinetic models considered. Its value was determined by the model-free methods, of which Flynn–Wall– Ozawa and Kissinger–Akahira–Sunose were the most appropriate for this purpose and resulted in similar values of activated energy. Once the activation energy was determined, the order of the reactions and the frequency factors of each stage were calculated by means of the Coats–Redfern model-based method in order to complete the determination of the kinetic triplet. From the results obtained, it was deduced that the most feasible reaction order was one.

Photo-fermentative Bio-hydrogen Production from Agricultural Residue Enzymatic Hydrolyzate and the Enzyme Reuse

Reducing sugars contained in agricultural residue hydrolyzates can potentially be utilized in microbial fermentations to produce biofuels and biogas. Different types of agricultural residues were employed for photo-fermentative bio-hydrogen production, and the cumulative hydrogen production data fit well to the Modified Gompertz Model. Corncob was determined to have the highest reducing sugar yield and cumulative hydrogen production (12.64 mg mL-1 enzymatic hydrolysate, 228.94 mmol L-1) and maximum hydrogen production rate (5.9677 mmol L-1 h-1). Enzyme reuse was investigated by single factor experiment design to reduce the cost of bio-hydrogen production. Taking reducing sugar yield and activity recovery efficiency as reference, substrate re-adsorption method at different temperature and time, then enzyme immobilization method at different load and pH were investigated in the process of enzymatic hydrolysis. The efficiency of enzyme utilization was enhanced via substrate re-adsorption and enzyme immobilization methods, which resulted in a 4-fold increase in recycling efficiency. The optimal enzyme reuse condition by substrate re-adsorption was a re-adsorption time of 90 min at a temperature of 15 °C, while the optimal condition by enzyme immobilization method was a pH of 4.8 and immobilized enzyme load of 400 mg.

Effect of different soilless growing systems on the biological properties of growth media in strawberry

Composts produced from different types of agricultural residues can be a suitable material for growth media or for use in field soils as amendment. The use of these composts in soilless growing systems (SGS) can improve sustainability. Using a randomized complete block design with three replicates, three growth media were compared in three soilless systems in two bioassays. Growth media compared were a composted cork thin waste mixed with rice hulls (2:1 v:v) (CCR), a peat growth media (P), and a coir fibre (CF). The soilless growing systems used were: open (O), closed (C) and closed with slow sand filtration (CSSF). Growth media microbial activities were determined by the measurement of β-glucosidase activity at the beginning of the bioassays. Physicochemical properties of the growth media were evaluated at the beginning of the bioassays. Microbial community profiles were determined by dilution plating on semi-selective media. Microbial activity and pH were higher in CCR than in P and CF. Electrical conductivity was lower in P than CCR and CF. At the beginning of the assays, Bacillus spp., and oligotrophic actinomycetes were higher in CCR than in P and CF. At two and a half months after transplantation, Bacillus spp., copiotrophic bacteria, oligotrophic actinomycetes, cellulolytic bacteria and oligotrophic bacteria were higher in CCR than in P and CF. In the CSSF system, the population of copiotrophic bacteria was the only cultivable group that was different to the other systems that were evaluated (O and C). The CSSF system reduced the fungal population. However, the highest fungal population was detected in the O system. The copiotrophic bacterial population was higher in rhizosphere than outside rhizosphere. Therefore, the growth medium and the system of soilless culture have significant effects on the population profiles of microorganisms in the rhizosphere.

Economic Optimization of a Lignocellulosic Biomass-to-Ethanol Supply Chain

This paper presents an optimization study of the net present value of a biomass-to-ethanol supply chain in a 9-state region in the Midwestern United States. The study involves formulating and solving a mixed integer linear programming (MILP) problem. A biochemical technology is assumed for converting five types of agricultural residues into ethanol utilizing dilute acid pretreatment and enzymatic hydrolysis. Optimal locations and capacities of biorefineries are determined simultaneously with biomass harvest and distribution. Sensitivity analysis is performed to elucidate the impact of price uncertainty on the robustness of the supply chain and whether or not the proposed biorefineries will be built or will fail financially after being built.

Crop residues as raw materials for biorefinery systems – A LCA case study

Our strong dependence on fossil fuels results from the intensive use and consumption of petroleum derivatives which, combined with diminishing oil resources, causes environmental and political concerns. The utilization of agricultural residues as raw materials in a biorefinery is a promising alternative to fossil resources for production of energy carriers and chemicals, thus mitigating climate change and enhancing energy security. This paper focuses on a biorefinery concept which produces bioethanol, bioenergy and biochemicals from two types of agricultural residues, corn stover and wheat straw. These biorefinery systems are investigated using a Life Cycle Assessment (LCA) approach, which takes into account all the input and output flows occurring along the production chain. This approach can be applied to almost all the other patterns that convert lignocellulosic residues into bioenergy and biochemicals. The analysis elaborates on land use change aspects, i.e. the effects of crop residue removal (like decrease in grain yields, change in soil N 2O emissions and decrease of soil organic carbon). The biorefinery systems are compared with the respective fossil reference systems producing the same amount of products/services from fossils instead of biomass. Since climate change mitigation and energy security are the two most important driving forces for biorefinery development, the assessment focuses on greenhouse gas (GHG) emissions and cumulative primary energy demand, but other environmental categories are evaluated as well. Results show that the use of crop residues in a biorefinery saves GHG emissions and reduces fossil energy demand. For instance, GHG emissions are reduced by about 50% and more than 80% of non-renewable energy is saved. Land use change effects have a strong influence in the final GHG balance (about 50%), and their uncertainty is discussed in a sensitivity analysis. Concerning the investigation of the other impact categories, biorefinery systems have higher eutrophication potential than fossil reference systems. Based on these results, a residues-based biorefinery concept is able to solve two problems at the same time, namely find a use for the abundant lignocellulosic residues and ensure a mitigation effect for most of the environmental concerns related to the utilization of non-renewable energy resources. Therefore, when agricultural residues are used as feedstocks, best management practices and harvest rates need to be carefully established. In fact, rotation, tillage, fertilization management, soil properties and climate can play an important role in the determination of the amount of crop residue that can be removed minimizing soil carbon losses.

Thermal Analysis Kinetics of Bagasse and Rice Straw

The role of added inorganic salt on the thermal degradation of lignin was studied. The results were compared with the thermal analyses of two types of agricultural residues: rice straw with high silica content and bagasse with low silica. Compared to wood, thermal decomposition of such materials is faster, with a dual mechanism concept similar to wood. In general, the activation energy for rice straw is about 19.3 Kcal mol while that of bagasse is 33.4 Kcal mol. This proves that inorganic material either inherited or added changed the thermal activities of the lignocellu losic materials.

Prediction of the Behaviour of Biomass Ash in Fluidized Bed Combustors and Gasifiers

Two types of agricultural residues (wheat straw and olive residue) in untreated and pretreated (fractionation, leaching) form were tested as concerns their ash melting behaviour during fluidized bed combustion and gasification by means of thermal analysis techniques. The techniques applied included DSC, simultaneous DSC/TG and TG-MS for the determination of low-temperature ash melts and losses caused by the volatilization of alkali material. In combination with ash elemental analyses on the materials, the applied techniques proved to offer valuable information for prediction of the ash behaviour in fluidized bed reactors.