Ratio Of Wheat Straw Research Articles

Synergistic interactions between lignite and biomass during co-pyrolysis from volatile release, kinetics, and char structure

One of the most efficient techniques to achieve efficient utilization of both is coal and biomass co-pyrolysis. Despite a great deal of recent research on the co-pyrolysis process, it is still unknown how biomass affects the co-pyrolysis's synergistic effect and how volatiles interact. This study uses a thermogravimetric analyzer to examine the weight loss law of co-pyrolysis of wheat straw, rice straw, and bamboo powder with various amounts of Zhundong coal. According to the findings, there is a strong positive interaction, a mild positive interaction, and a negative interaction when three different types of biomass (wheat straw, rice straw, bamboo straw) are co-pyrolysis with Zhundong coal. The interaction between wheat straw and Zhundong coal is the strongest when the mass ratio of wheat straw to Zhundong coal is 6: 4. Using a thermogravimetric-infrared spectrometer, the changes in volatile functional groups during co-pyrolysis are investigated. It is discovered that adding wheat straw decreased the amount of CO2 produced by Zhundong coal pyrolysis. Regarding the mechanism of co-pyrolysis, the alkali and alkaline earth metals (AAEMs) on the surface of biochar catalyze the pyrolysis of Zhundong coal, while the “hydrogen donor” and “free radical donor” generated by biomass pyrolysis inhibited the cross-linking and polymerization of macromolecular volatiles produced by Zhundong coal pyrolysis. The activation energy of the mass ratio of wheat straw to Zhundong coal = 6: 4 sample is calculated by three model-free methods. The co-pyrolysis process's average activation energy is determined to be between 175.95 and 194.18 kJ/mol. Through scanning electron microscopy, it is found that the morphology of co-pyrolysis carbon is significantly different from that of single pyrolysis carbon. The porous structure of biochar promotes the secondary cracking of heavy volatiles produced by coal pyrolysis, while the cracking of volatiles further promotes the development of the pore structure of biochar.

Bacterial community structure and metabolites after ensiling paper mulberry mixed with corn or wheat straw

BackgroundIn this study, we aimed to address the low utilization of straw and poor fermentation quality of paper mulberry silage (under natural fermentation conditions). Straw was combined with paper mulberry for ensiling, and the fermentation characteristics, bacterial community, and metabolite composition of the mixed straw and paper mulberry silage were investigated. Four treatment groups were established: corn-straw treatment 2 (3:7 ratio of corn straw to paper mulberry), corn-straw treatment 3 (5:5 ratio of corn straw to paper mulberry), wheat-straw treatment 2 (3:7 ratio of wheat straw to paper mulberry), wheat-straw treatment 3 (5:5 ratio of wheat straw to paper mulberry), and a control group (ensiling of paper mulberry alone).ResultsThe control group demonstrated the highest pH and ammonia (AN) and acetic acid (AA) content compared with all the treatment groups. Corn-straw treatment 2 had the highest lactic acid content (54.70 g/kg dry weight) compared with the control and other treatment groups. The relative abundance of Enterobacter (7.085%) was the lowest in the control than in the other treatment groups (p < 0.05). The relative abundance of Enterococcus was higher in both the control and wheat-straw treatment 2 (22.03% and 21.29%, respectively) than in other treatment groups. The relative abundance of Lactococcus was highest in wheat-straw treatment 3 (15.83%) compared with the control and other treatment groups. Corn-straw treatments 2 and 3 demonstrated the same metabolite composition but were clearly different from the wheat-straw treatment 2, wheat-straw treatment 3, and the control. Diacetoxyscirpenol (DAS) belongs to the Fusarium metabolite type A trichothecenes, which were not detected in corn or wheat silage. DAS was downregulated in the wheat-straw treatment 3 and both corn-straw treatments compared with the control, which indicates that the addition of straw decreased mycotoxin production. Lactococcus was significantly and positively correlated with gluconic acid content (R2 = 0.5166).ConclusionOur results suggest that straw treatment can improve the nutritional value of paper mulberry silage by decreasing mycotoxin production, pH value, and AN content and increasing lactic acid production.

Study on characteristics, hydrogen-rich gas, bio-oil production, and process optimization of co-pyrolysis of sewage sludge and wheat straw

Sewage sludge (SS) and wheat straw (WS) are wastes that need to be treated urgently. In this research, the co-pyrolysis of SS and WS was investigated utilizing a thermogravimetric analyzer (TG) and a fixed bed. Using the Coats-Redfern approach, the effects of the mix ratio and the interactions of the SS and WS were investigated, and the effects of mix ratio, N2 flow rate, and pyrolysis temperature were examined for fixed bed pyrolysis. The response surface method (RSM) was applied in fixed bed pyrolysis to optimize the process. Increasing WS ratio can reduce pyrolysis residual rate to 23.8% for TG analysis. The reaction activation energy (E) increased with WS ratio. For the co-pyrolysis, there were substantial interactions between 200 and 400°. For fixed bed pyrolysis, syngas and bio-oil yields were mainly affected by N2 flow rate and pyrolysis temperature. The components with the highest amount in bio-oil gradually changed from aliphatic to aromatic hydrocarbons as the WS proportion grew, demonstrating that WS pyrolysis produced mostly aromatic compounds whereas SS pyrolysis produced more aliphatic compounds. Temperature 600 °C, sludge mixing ratio 32%, flow rate 2.5L/min, anticipated maximum H2 0.0421 m3/kg, and maximum bio-oil of 50.7114 g/kg are the best circumstances according to RSM.

Evaluation of oxy-organosolv pretreatment on lignin extraction from wheat straw

To develop a characteristic “Lignin-first” strategy, the oxy-organosolv delignification processes under mild conditions were comprehensively investigated. Results showed that lignin yield could achieve about 50 % under the optimum process conditions of ethanol concentration 80 %, temperature 90 °C, liquid to wheat straw ratio 25:1 for powdery-scale substrates, which was 65.0 % higher than that for rod-scale substrates under the same conditions. The lignin structural and carbohydrate component results demonstrated the employment of oxygen induced great quantities of lignin dissolving out on the premise of little carbohydrate component (<1 %) and lignin structural (mainly β-O-4 units) changes. Moreover, based on the molecular weight and polydiversity comparison results, the aqueous oxygen could transfer homogeneously in mild organosolv system and result in lignin degradation uniformly. Besides, the employment of oxygen assisted in not only extending the massive lignin removal stage to 30 min and 50 min for P-OEEL and R-OEEL respectively, but also boost the delignification rate with comparison to P-EL and R-EL. Lastly, the excellent anti-oxidant properties of lignin from oxy-organosolv process were demonstrated by scavenging DPPH and ABTS radicals. The economic calculations showed that the cost for lignin production were about 1.58USD/g lignin from powdery-scale wheat straw, providing a competitive route for high-value utilize waste biomass.

Application of low-cost natural zeolite catalyst to enhance monoaromatics yield in co-pyrolysis of wheat straw and waste tire

This study explored the impacts of low-cost natural zeolite (NZ) catalyst application on production of aromatic hydrocarbons during co-pyrolysis of wheat straw (WS) and waste tire (WT). Various blend ratios of WS and WT (1:0,3:1,1:1,1:3 and 0:1) were investigated to determine the optimum ratio in the terms of oil quantity and quality. The blend ratio of WS:WT 1:3 was observed to be optimum combination with oil, char and gas yields of 45, 36 and 19 wt% respectively. The catalyst was found to have silicon to aluminum ratio (SAR), surface area and pore size of 7.39, 4.2 m2/g and 23.10 Å respectively. The incorporation of NZ catalyst into WS, WT and their blend ratio of 1:3 improved the quality of oil in the terms of hydrocarbons and physiochemical properties compared to their respective ratios in non-catalyst pyrolysis. The total hydrocarbons content was increased from 72.00 area% in case of non-catalytic pyrolysis of WS:WT (1:3) to 86 area% with addition of NZ while oxygenates were reduced from 20.20 to 10.50 area% respectively. The contents of desired aromatic hydrocarbons such as benzene, toluene and xylene (BTX) were increased to 61.0 area% in catalytic pyrolysis for WS:WT 1:3 compared to 45.59 area% in non-catalytic pyrolysis of the same combination. Moreover, the higher heating value (HHV) of 42.15 MJ/kg was observed in catalytic pyrolysis of WS:WT (1:3) compared to 40.70 MJ/kg in non-catalytic pyrolysis. Besides, Kinematic viscosity and density of the oil also improved with addition of catalyst.

Comparative study on the effects of wood dust and rice husk on wheat straw gasification process: Ash fusion characteristics and gasification reactivity

The ash fusion characteristics and gasification reactivity of wheat straw (WS) blended with rice husk (RH) and wood dust (WD) were investigated, respectively. Furthermore, the transformation of minerals and synergy behaviour of gasification reactivity were explored. Results demonstrated that both RH and WD could enhance the ash fusion characteristic temperatures of WS, which were due to the increasing contents of higher melting-point compounds (quartz and tridymite in WS/RH mixtures, and Ca-silicates in WS/WD mixtures) and the decreasing contents of lower melting-point K-based compounds. Compared to pure WS, the deformation temperature of WS/RH mixture increased from 780 °C to 1233 °C at an RH ash ratio of 60%, and that of WS/WD mixture increased to 1065 °C at a WD ash ratio of 20%. Based on the appropriate ratio of WS, the gasification reactivity of WS increased with increasing WD ratios, whereas that of WS decreased with increasing RH ratios. Besides, the presence of synergistic effect and the reduction of activation energy were observed in two co-gasification processes.

Growth performance and carcass characteristics of fattening Awassi lambs fed willow silage

Providing at least 20% roughage straw is needed to achieve optimal final body weight and feed efficiency in Awassi lambs but the supply of straw has become unpredictable in Jordan, due to erratic rainfall patterns. In order to determine if wastewater-irrigated willow silage (WS) can replace wheat straw in fattening lambs' diets, Awassi lambs were randomly assigned to three high-concentrate diets that included 0 (W0), 10 (W10), and 20% (WS20) of willow silage, on dry matter basis. Lambs in WS0 were fed wheat straw (S) as sole source of roughage; lambs in WS10 were fed a 1:1 ratio of wheat straw and willow silage while WS20 were fed willow silage as sole roughage. Concentrates were formulated to achieve iso-caloric, iso-nitrogenous diets. Lambs were housed in individual pens and fed high concentrate diets for 90 days, after which, five lambs of each group were slaughtered. Growth performance, carcass characteristics, and meat quality parameters were assessed. Feeding willow silage did not affect DM, CP, NDF, and ADF intakes, average daily gain and the feed to gain ratio. Hot and cold carcass weights, dressing percentages and weight of internal organs, meat pH, cooking losses, and water holding capacity were all unaffected by feeding willow silage. Less (P < 0.01) non-consumable mesenteric and kidney fat but more (P < 0.05) valuable tail fat accumulated in carcasses from lambs fed with willow silage. Feeding willow silage was also associated with decreased shear-force of the meat and improved tenderness score. In contrast, loins were heavier (P < 0.002), and Longissimus dorsi muscles were heavier (P < 0.05) and deeper (P < 0.001) in WS0 lambs, and no significant difference was noted for colour attributes. In conclusion, willow silage can replace wheat straw as source of roughage, encompassing a trade-off between advantages, i.e., improved patterns of fat deposition in the carcass and improved meat tenderness, and drawbacks, i.e., smaller loins and L. dorsi muscles.

One-pot conversion of wheat straw into biobased chemicals in methanol/water medium using cheap mixed acid catalyst.

Environmental concerns and the diminishing availability of unrenewable resources have spurred research into the use of agricultural waste as a feedstock for industrial applications. Efficient conversion of wheat straw into biobased chemicals is an important way to realize the potential value of renewable agricultural biomass. This study investigated one-pot conversion of wheat straw into two notable platform chemicals, levulinic acid (LA) and methyl levulinate (ML). A mixed acid catalyst system, including 1% H2 SO4 and 0.015mol L-1 Al2 (SO4 )3 , was an efficient catalyst for the conversion of wheat straw due to the combination of Brønsted acid and Lewis acid. A ratio of wheat straw to methanol of 5g/50 mL was identified as the preferred solid/liquid ratio, and a methanol/H2 O medium with 25% water content aided the simultaneous production of LA and ML from wheat straw. Under optimum conditions, the maximum total yield of LA and ML reached 23.01% at 220 °C and 3h. The kinetics of biobased chemical formation and the reaction pathways in methanol/water were investigated. The presence of water in the methanol/H2 O medium affected the distribution of products and promoted hydrolysis reactions. The methanol/H2 O medium not only inhibited the side reactions but also promoted the degradation of wheat straw and increased the total yield of LA and ML. This study provides a feasible method for the conversion of wheat straw to prepare biobased chemicals. © 2021 Society of Chemical Industry.

Dimensional stability and mechanical properties of bio-based composites produced from hydro-thermal treated wheat straw

Bio-composites were produced from untreated (UT) and hydro-thermally treated (HTT) wheat straw (WS) particles and wood, and their dimensional stability and mechanical properties were investigated. The HTT treatment consisted of subjecting the WS particles to a steam explosion process for 8 min at 180 °C. The HTT and UT WS particles were mixed with the wood particles at 10, 20, 30, and 40% ratios. The physical properties, including density, water absorption (WA), and thickness swelling (TS), were determined for the bio-based composites. The mechanical properties evaluated included the modulus of rupture, modulus of elasticity, and internal bond strength. Statistical analyses showed that the hydro-thermal treatment and the WS ratio had significant effects on the dimensional stability and mechanical properties of the bio-composites. The WA of the composites after 2-h and 24-h rose significantly when the HTT WS particle ratio was increased from 10 to 40%. The 2-h and 24-h WA values of HTT-10 were 6.3% and 5.3% lower than those of UT-10, respectively. Improvements in the 2-h TS value were achieved by the HTT WS particles at the 10% ratio, and in the 24-h TS value at the 10 and 40% ratios. The mechanical properties of the composites were higher in the HTT group, but decreased in both the UT and HTT groups as the WS ratio increased.

Effects of Wheat Straw and Ashing Temperature on the Ash Fusion Characteristics of Food Waste

The disposal of food waste (FW) has brought severe challenges to the environment and society, the application of gasification technology provides new ideals for its resource utilization, and the effective slagging is one of the key points for this technology. This study mainly focuses on the ash fusion characteristics of FW under different temperature and wheat straw (WS) addition conditions, and analyses of XRF, XRD and SEM were performed to characterize the properties of the ashes. Results show that the ash fusion temperatures (AFTs) of FW were higher than that of WS, and both increased with the temperature due to the volatilization of alkali metals and the formation of high melting points substance such as quartz and mullite. The AFTs of FW decrease by about 23 °C with the blending of 10% WS at 800 °C, and it decreases non-linearly with increasing WS ratio, which mainly originated from the interaction between the ashes of FW and WS. Although the increase of mullite content makes the AFTs of WS50 higher than the calculated value, the increase of low melting point substances such as anorthite and the existence of leucite in WS50 resulting in its lower AFTs than that of FW.

Synergistic effect of mixing wheat straw and lignite in co-pyrolysis and steam co-gasification

Co-pyrolysis and steam co-gasification of wheat straw (WS) and lignite coal (LC) were studied in a tube furnace between 700 °C and 900 °C. Synergistic effect in co-pyrolysis is not always apparent. However, with the introduction of H2O vapor, synergetic effect is more obvious. Gas volume generated by co-gasification was higher than the prediction in all cases. Meanwhile, temperature played an important role and had a linear relationship with the excess gas volume when it exceeded 800 °C. These findings can be explained by that sufficient H2O vapor could enhance synergy according raising catalytic effect of alkali and alkaline earth metals (AAEMs), promoting free radical generated and increasing reactivity of half-chars. Moreover, co-gasification of WS and LC with several blending ratios were studied at 850 °C. It found H2O vapor could promote free radical formation stronger with higher ratio of WS during co-gasification, thus showing an enhancing effect on the reactivity of WS-derived chars.

Effect of supplementing total mixed ration with ajwain (Trachyspermum ammi) oil on the performance of buffalo calves

This study was taken up to assess the impact of different levels of ajwain oil (rich in essential oils) on the nutrient utilization by in vitro gas production technique. The best level of ajwain oil obtained was tested on the performance of buffalo calves. Ajwain oil was supplemented at 0.05, 0.1, 0.15 and 0.2% of total mixed ration (TMR; concentrate:green fodder:wheat straw in 40:48:12 ratio on DM basis). The results revealed that supplementation of incremental levels of ajwain oil to the TMR resulted in linear decrease in net gas production (NGP), digestibility of true OM and NDF; ME availability and methane production. Supplementing the TMR with ajwain oil beyond 0.05% resulted in significant depression in total and individual volatile fatty acids (VFAs) and acetate to propionate ratio. The protozoa numbers declined linearly with increase in level of ajwain oil supplementation. Hence 0.05% level of ajwain oil was selected for assessing its impact on performance of growing buffalo calves. In the first experiment, a 146-day feeding trial was conducted on 20 male buffalo calves divided into 2 groups, offered a TMR-1 (concentrate: green fodder: wheat straw ratio of 40:48:12 on DM basis) or TMR-1 supplemented with 0.05% ajwain oil. After completion of this trial, another 138-day feeding trial was conducted on 18 male buffalo calves divided into 2 groups and were offered a TMR-2 (concentrate: wheat straw ratio of 50:50 on DM basis) or TMR-2 supplemented with 0.05% ajwain oil. In the first growth trial, supplementing the control diet with ajwain oil did not show any impact on daily DM intake, digestibility of nutrients and N-retention, but in the second experiment the digestibility of all the nutrients, except that of crude protein was improved significantly in the ajwain oil supplemented group. The daily DM intake and N-retention was comparable in both the groups. The blood profile, urinary purine derivatives excretion and microbial biomass synthesis was not affected by ajwain oil supplementation during both the experiments. The average daily gain was comparable between control and ajwain oil supplemented group in both the feeding trials. It was concluded that supplementing ajwain oil to the TMR suppressed the in vitro methane production; improved the digestibility of nutrients in wheat straw based TMR supplemented with 0.05% ajwain oil, but did not show any significant beneficial effect on the performance of buffalo calves.

Hemp-Straw Composites: Gluing Study and Multi-Physical Characterizations.

In order to meet the requirement of sustainable development, building materials are increasingly environmentally friendly. They can be partially or fully bio-based or recycled. This paper looks at the development of fully bio-based composites where agro-resources are valued as bio-based aggregates (hemp) and as binding materials (wheat). In a previous work, a feasibility study simultaneously investigated the processing and ratio of wheat straw required to ensure a gluing effect. In this paper, three kinds of hemp-straw composites are selected and compared with a hemp-polysaccharides composite. The gluing effect is analyzed chemically and via SEM. The developed composites were characterized multi-physically. They showed sufficiently high mechanical properties to be used as insulating materials. Furthermore, they showed good thermal performances with a low thermal conductivity (67.9–69.0 mW/(mK) at 23 C, dry).

Energy Utilization Potential of Wheat Straw in an Ecological Balance—A Case Study of Henan Province in China

Minimum volume of straw should be retained in collecting wheat straw in order to obtain sustainable agricultural biomass energy and measure the energy utilization potential of wheat straw when considering ecological balance. Based on relevant literature, this paper calculates the minimum, medium, and maximum volume of wheat straw retention in various types of soil and designs three different scenarios of minimum, medium, and maximum wheat straw retention. Taking Henan province in China as a case, this paper calculates the potential of wheat straw for energy utilization using linear regression method and scenario analysis, with consideration of influencing factors such as the harvest coefficient and combustion ratio of wheat straw. The results show that the energy utilization potential of wheat straw in Henan province in 2020, 2030, 2050 are 13.77, 16.48, 22.54 million tons of coal equivalent (TCEs), respectively, in the minimum retention scenario, assuming that wheat straw is not directly used for combustion. Excessive straw left in the field causes resource waste and produces CH4 and other greenhouse gases. This paper finds that energy potential of wheat straw for energy utilization is limited when ecological balance is considered, however, it is beneficial to the sustainable development of crop biomass energy.

Improving the co-digestion performance of waste activated sludge and wheat straw through ratio optimization and ferroferric oxide supplementation

Low anaerobic digestion efficiency of wheat straw (WS) has been an intractable problem owing to its high C/N ratio and complex structure. In this study, co-digestion of WS and waste activated sludge (WAS) at different ratios was performed to identify conditions that would elevate the acidic pH and increase methane production. The results showed that using a 1:1 ratio of WS and WAS, methane production in the co-digester was 26.9% higher than the sum of equal WAS and WS mono-digestion. When Fe3O4 was added to the co-digester, the acidic pH was further relieved and the anaerobic digestion efficiency was additionally enhanced. Microbial analysis showed that the ethanol-type fermentative bacterial genus Ethanoligenens was enriched in the WAS + WS-Fe3O4 reactor, in which the production of propionate was notably reduced, indicating that Fe3O4 could prevent the accumulation of volatile fatty acids by changing the types of fermentative bacteria present and promote anaerobic digestion efficiency.

Effect of different acid catalysts on the properties of activated carbon fiber precursors obtained from phenolated wheat straw

ABSTRACTIn this study, wheat straw (WS) was successfully liquefied into phenol (Ph) in the presence of sulfuric and phosphoric acid at different Ph:WS ratios. The liquefied wheat straw (LWS) was mixed with the crosslinking agent hexamethylenetetramine and applied for manufacturing of activated carbon fiber precursors (ACFPs) via melt-spinning. The ACFPs were cured into a solution consisted of hydrochloric acid and formaldehyde. The morphological, thermal, and chemical properties of the ACFPs were investigated using microscopic, thermogravimetric, and spectroscopic analyses while the amount of the combined phenol (CPh) was determined via liquid chromatography. The results indicated that the type of the acid catalyst and Ph:WS ratio had a great impact on CPh and unliquefied residue. The sulfuric acid showed better performance due to its strong acidic characteristics. The results of the analyses depicted that the ACFPs obtained from sulfuric acid-based LWS resin had a more decent morphological texture, thermal resistance, and chemical structure.

Hemp-Straw Composites: Thermal And Hygric Performances

The European ISOBIO project aims to develop new bio-based building insulating materials which contribute to reduce environmental impacts of buildings. The developed materials shall have low embodied energy and low carbon footprint and shall contribute to reduce energy needs of buildings and to ensure high hygrothermal comfort of users. This study investigates the valuation of agro resources as bio-based aggregates and as binding material to produce wholly bio-based composites. The developed composites are made of hemp shiv glued with wheat straw. After a feasibility study which investigates several ways to use wheat straw as a gluing material and several hemp to wheat straw ratio, three hemp-straw composites are selected. Specimens are produced to characterize thermal and hygric properties of developed composites. They show interesting thermal and hygric properties as they have low thermal conductivity (0.071 to 0.076 W/(m.K)) and they are excellent hygric regulators (MBV > 2 W/(m².%RH)).

Performance evaluation on co-gasification of bituminous coal and wheat straw in entrained flow gasification system

Co-gasification of coal and biomass can reduce the CO2 emission and the consumption of fossil fuel. Kinetic analysis and products distribution evaluation are essential to the gasifier design and operation optimization. In this paper, the thermal behavior on co-gasification of a kind of bituminous coal blended with wheat straw was investigated by the thermal gravimetric analyzer and distributed activation energy model. Gaseous products evolution during co-gasification was explored by entrained flow gasification system. The influence of gasification temperature (1100–1400 °C), biomass mixing ratio (0, 0.25, 0.5, 0.75, 1), and oxygen/carbon ratio (0.35–0.65) on H2 and other gaseous products was considered. The result indicated that the adding of wheat straw promoted the gasification performance. The value of Tgin (initial gasification temperature) and Gi (gasification reactivity index) increased as the increasing mass ratio of wheat straw. The distributed of gasification activation energy showed positive synergistic effect. The value of gasification activation energy gradually decreased from 193.58 to 100.62 kJ mol−1, 115.11 kJ mol−1, 129.57 kJ mol−1 as the mass ratio of wheat straw increased from 0.25 to 0.75. The content of H2 and CO increased with the rising of gasification temperature, and the content of CO2 and CH4 showed the opposite trend. At the same time, cold gas efficiency (CGE) increased with the raising of gasification temperature, indicating that the improvement of gasification temperature is beneficial to the improvement of co-gasification gas quality. The content of H2 and CO2 also increased the growth of wheat straw mass ratio. Synergistic effect of gaseous distribution was also observed, especially in 50% of biomass ratio. As the increasing of oxygen–fuel ratio, the content of H2 and CH4 decreases gradually. Synthesizes each kind of condition with the operation condition of gasification equipment and the quality of gaseous products, the gasification temperature of 1300 °C and the oxygen–fuel ratio of 0.45 were the optimum operating parameters for co-gasification of bituminous coal and straw. This research can provide basic information for process design and parameter selection of co-gasification.

Improvement and Characterization in Enzymatic Hydrolysis of Regenerated Wheat Straw Dissolved by LiCl/DMAc Solvent System.

Lithium chloride (LiCl)/N,N-dimethylacetamide (DMAc) solvent system was used to dissolve native and pretreated wheat straw materials in order to promote the enzymatic hydrolysis process. The dissolution ratio of wheat straw in LiCl/DMAc solvent system increased when dilute sulfuric acid or ethanol-sulfuric acid mixture pretreatment was conducted before dissolution. The materials regenerated from LiCl/DMAc solution exhibited obvious changes in structure and morphology, as revealed by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The cellulose and xylan digestibilities of regenerated materials were improved obviously. The cellulose digestibilities of materials regenerated from native and pretreated wheat straw by dilute sulfuric acid and ethanol-sulfuric acid mixture were 61.8, 81.2, and 84.4%, respectively, with 25 FPU of cellulase and 187IU of xylanase after 96h. These values were significantly higher than the digestibilities of 0, 33.2, and 57.5% obtained from corresponding materials before dissolution. Dissolution treatment of wheat straw by LiCl/DMAc solvent system provides an alternative method for efficient enzymatic hydrolysis.

Effect of Hydrodynamic Conditions on Emissions of NOx, SO2, and CO from Co-Combustion of Wheat Straw and Coal Under Fast Fluidized Bed Condition

ABSTRACTShare of renewable energy targets and global pollutant emissions are driving the increased utilization of CO2 neutral biomass. Effect of operating conditions like solid circulation rate, Ca/S molar ratio, and fluidizing velocity on emissions of NOx, SO2, and CO for burning different blends of wheat straw and Salt Range coal under fast fluidized bed conditions in a pilot scale test facility are reported in this study. Effect of bed temperature, excess air ratio, and secondary to primary air ratio on the emissions has already been published in the journal Combustion Science and Technology. In this study emissions of NOx, SO2, and CO were found to decrease with the increased wheat straw ratio and solid circulation rate. SO2 and NOx emissions were observed to decrease with the decrease in fluidizing gas velocity while tradeoff relationship was found between the NOx and CO emissions with the increase in Ca/S molar ratio.