Ratio Of Straw Research Articles

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.

Simulation of cattle stomach processes applied to the fermentation of mixed manure and straw

The cattle stomach was considered as the basis for simulating a proposed operation. Microenvironmental degradation mechanisms are understood to be key to the efficient utilization of straw and other resources. Through dynamic tracking of the change law of heat generated by microbial degradation of straw in the cattle stomach, this study used an orthogonal test to explore the optimal ratio of feeding feed, the degradation mechanism in the microenvironment, and the characteristics of cattle manure and straw anaerobic fermentation. The results showed that the number of days of fermentation and the ratio of straw and cattle manure had a significant impact on methane gas production, and the mixture ratio was 1:3, at 26 °C; within 20 days, the cumulative gas production was up to 78.9 L. The results also showed that rumen microorganisms, cattle manure, and mixed straw fermentation can be used at different ratios to obtain the change of methane production, and determine the best ratio to achieve the maximum gas production.

Comprehensive analysis on the in-situ ash fusibility and mineral reactions of ash mixtures in the co-gasification process

Biomass can effectively modify coal ash fusibility and alleviate several operational issues like agglomeration, sintering, and erosion for slagging gasifiers. The key issue is to clarify the ash fusion properties and mineral transformation during the heating process. The fusion temperatures, mineral evolutions, in-situ morphology observation and thermodynamic analysis of the coal, biomass and biomass-coal blended ash samples were systematically evaluated in this paper. The ash fusion temperatures (AFTs) presented V-type curves with the increasing rape straw ratio. Then the bottom point occurred at the ratio of 50 wt% due to the reduction of refractory minerals (mullite, quartz, < 50 wt%; kalsilite, oldhamite, >50 wt%) and the increase of low-melting-point minerals and their eutectics (leucite and anorthite). Besides, the thermodynamic calculation can provide the basis for the prediction of ash fusion behavior. The in-situ morphology evolutions of blended ashes further revealed the relationship between ash fusion behaviors and morphological changes. Namely, the terminative sintering and melting temperature were highly related to the ash deformation temperature and flow temperature, R2 was 0.9901 and 0.9846, respectively. The significant work could guide the mixing conditions during the co-gasification of high‑silicon‑aluminum coal and biomass and improve the ash fusion properties.

Simulation of the Nitrogen and Phosphorus Leaching Characteristics under Different Filter Materials of an Improved Subsurface Drainage

Leaching characteristics of filter materials of the improved subsurface drainage are very important for nitrogen and phosphorus loss. In this paper, the leaching characteristic of soil, sand, straw, and zeolite under different layouts were studied by HYDRUS-2D simulation based on calibration and validation according to laboratory data. Two scenarios were considered, including different soil and filter layouts, and mixed filter materials of straw and sand or zeolite. The results indicate that zeolite showed good adsorption characteristics of both ammonia nitrogen and phosphorus, while the straw’s adsorption characteristics were very different between ammonia nitrogen and phosphorus. Nitrogen and phosphorus concentrations of the outflow were mostly determined by the materials around the outlet. Compared with the cases of no lower soil, when the lower soil depth was 5 cm, the ammonia nitrogen concentrations under sand and straw decreased 54.5% and 96.3%, and the corresponding decreased phosphorus concentrations were 84.1% and 96.2%. In views of mixed filter with straw and the different layouts, that the ratio of straw and sand was 1:1, or the ratio of straw and zeolite was 2:1; at the same time, sand and zeolite should be set around the outlet, and may be better for ammonia nitrogen and total phosphorus concentrations reduction.

Growth and yield of several Gogo rice varieties (Oryza Sativa L.) applicated by various P sources in Ultisol Planting Media

Gogo rice productivity is still low because farmers still use local varieties of Gogo rice and most of it is cultivated on marginal soils such as Ultisol. Ultisol soils contain low available P due to P fixation by Al and Fe. The existence of Gogo rice varieties that can compensate for the high Al content in Ultisol soil and can neutralize Al in plants is one of the right solutions in overcoming the problem of Al poisoning. While the constraint of the lack of availability of P nutrients in Ultisol requires the application of P fertilizer. This study aims to determine the growth and yield of several Gogo rice varieties given various P sources and to determine the best Gogo rice varieties and the best P sources in Ultisol. The research method used a Split Plot Design. The main plot is Gogo rice varieties consisting of three levels, namely; Kuku Balam, Dogor, and Inpago 10, as well as subplots are various sources of P consisting of four levels, namely; No P, 0.4 g TSP, 0.7 g rock phosphate, and 1.8 g guano. The results showed that administration of 0.4 g TSP was the best source of P in Gogo rice than without P, ​​administration of RP, and guano on the value of P nutrient uptake, maximum tillers, productive tillers, flowering age, harvest age, number of grains per panicle, percentage pithy grain, the weight of dry milled grain per clump and the ratio of grain and straw. The Kuku Balam variety had a nutrient uptake value of P (130.91 mg/clump), the number of grains per panicle (210.63 grains) and the weight of milled dry grain per clump (42.11 g) which were the best yields compared to the Dogor and Inpago 10.

Effect of temperature and fly ash content on the catalytically pyrolyzed rice straw biochar–fly ash composites for methylene blue adsorption

AbstractRice straw and fly ash are the wastes produced in abundance which need immediate attention for their management. In the present study, the in situ pyrolysis of rice straw in presence of fly ash was carried out and the resultant composites were studied for adsorption of methylene blue (MB). Slow pyrolysis of rice straw in presence of fly ash is evaluated using thermogravimetric analysis (TGA) and Coats–Redfern equation for pseudo‐first‐order reaction kinetics, respectively. The activation energy (Ea) for the pyrolysis of rice straw was 41.75 kJ/mol which was lowered to 37.39 kJ/mol in presence of fly ash. Biochar fly ash composites BFA41–3, BFA51–3, and BFA61–3 were prepared at three 400°C, 500°C, and 600°C pyrolysis temperature, respectively, the subscript indicating three different ratios of rice straw and fly ash (1:3, 1:1, and 3:1 w/w ratio). The composites BF4–61–3 were neutral to alkaline in pH, due to the presence of basic oxide and carbonates minerals. BFA4–61–3 was studied for batch adsorption of MB and optimized for pH, dose, and initial concentration of adsorbate. The maximum MB adsorption capacity of 25.91 mg/g was reported for the composite BFA41. MB adsorption efficiency (qe) followed the trend BFA41–3 &gt; BFA51–3 &gt; BFA61–3, which indicates a strong influence of biochar surface functional groups on dye adsorption, as reiterated by the multiple linear regression (MLR) analysis. Stripping of MB was achieved using methanol as a stripping agent for MB‐adsorbed BFA4–61–3 with desorption efficiency of 7% to 11% in the first cycle and 23% to 100% in the second cycle. Thus, the biochar fly ash composite with optimum ion exchangeable functional organic moieties would be suitable for dye remediation and waste generated in the process could find application in soil amelioration.

Evaluation of Gas Production, Fermentation Parameters, and Nutrient Degradability in Different Proportions of Sorghum Straw and Ammoniated Wheat Straw

The purpose of this study was to investigate the optimum proportion of sorghum straw and ammoniated wheat straw in vitro and in vivo to apply in ruminant diets. One-factor and two-factor experimental designs were used in the in vitro tests, with different ratios of sorghum straw to ammoniated wheat straw (S:AWS) of 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, and 8:2 to measure the in vitro total gas production, CH4 production, in vitro dry matter degradability (IVDMD), in vitro organic matter degradability (IVOMD) and in vitro fermentation parameters. Additionally, the nylon bag technique was used to determine the dynamic degradation of these different ratios of mixed feedstuffs for incubating in sheep rumen for 6 h, 12 h, 24 h, and 48 h. The results show that IVDMD, IVOMD, and the molar ratio of propionate were the highest when the ratio of S:AWS was 8:2 (p &lt; 0.05) in vitro; however, this ratio released much more CH4 (p &lt; 0.05). In addition, the degradability of DM, OM, CP, and ash and the effective degradability of DM and CP were the highest when the ratio of S:AWS was 8:2 cultured in sheep rumen for 48 h (p &lt; 0.05). In the in vitro and in situ nylon bag tests, IVDMD, IVOMD, rumen nutrient degradability, and effective degradability of DM and CP increased with the increase in the sorghum straw proportion. In conclusion, the higher the proportion of sorghum straw, the higher the nutrient degradability in vivo and in vitro, but also the higher the emissions of CH4. Therefore, when the ratio of S:AWS is 8:2, ruminants can effectively utilize nutrients in feed.

Nitrogen content and C/N ratio in straw are the key to affect biological nitrogen fixation in a paddy field

Straw amendment can increase nitrogen fixation in paddy field, however, the efficiency of carbon sources with different biochemical properties to enhance N2 fixation and nitrogen fixation activity is still unclear. A 15N2-labelling system was used in the field environment to determine biological nitrogen fixation (BNF) under the addition of three kinds of straw. The nifH gene (DNA) and nifH RNA gene (cDNA) of soil were amplified by real-time fluorescent quantitative PCR. The diversity and community composition of nitrogen fixing microorganisms were studied by high-throughput sequencing. The study is expected to reveal how different carbon sources impact biological nitrogen fixation and its mechanism in the paddy field system. Results showed that the absolute abundance diazotrophs in the treatment of mature stage wheat straw (MWS) was 4.88 times as high as that in the CK treatment, but jointing stage wheat straw (JWS) and poplar branch (PB) did not induce any significant changes. Straw amendment had no impact on cyanobacteria abundance. The proportion of N2 fixation increased by MWS was 2.07 times, but which was much lower than the increase proportion of the heterotrophic diazotrophs, leading to a decrease of diazotrophic nitrogen fixation activity. Mature wheat straw addition increased biologically fixed nitrogen in paddy field by increasing the number of heterotrophic nitrogen fixing bacteria. The results indicated that to increase biological N2 fixation in paddy system, straws with low nitrogen content and high C/N ratio were recommended.

Release Kinetics of Carbon, Nitrogen, Phosphorus, and Potassium During Co-composting of Poultry Manure Mixed with Different Ratios of Wheat Straw and Zeolite

Release Kinetics of Carbon, Nitrogen, Phosphorus, and Potassium During Co-composting of Poultry Manure Mixed with Different Ratios of Wheat Straw and Zeolite

Production of Oyster Mushroom Using Sterilized and Carbonized Fruiting Bags: A Comparative Study

The study was conducted for production of oyster mushrooms using sterilized and carbonized fruiting bags. Using these agro-wastes as substrates in different mixture proportions, the productivity of oyster mushrooms was investigated in terms of the number of yields, mass, size, and height. An experimental research design was used to test the hypothesis of the significant difference in the yields and growth of oyster mushrooms between SPH-LS and CPH-LS. The percentage, weighted mean, ANOVA TEST, and two-tailed test were used to interpret the data gathered based on a comparative study of mushroom productivity in terms of the earlier mentioned variables. Analysis of data revealed that SPH-LS (25%?75%) is not significantly different (p > 0.05) from CPH-LS (25% ? 75%) as both showed almost the same average height produce. However, compared with the other two CPH-LSs is more recommended. Carbon could be mixed with another substrate rich in cellulose to grow mushrooms. The results showed that increasing the percentage of lye straw in the CPH and the SPH increases the yields, mass, and size of oyster mushrooms. This means that the said mixture combination is effective for mushroom production; however, no significant effect in the height of the mushroom in different mixture proportions with (P=0.015) was recorded. The results showed that increasing the percentage of lye straw in the carbonized palay husks and the sterilized palay husks increases the yields, mass, size and height of oyster mushrooms. Substrates with sterilized palay husks 25% with lye straw 75% were the most suitable substrate formulas for the cultivation of oyster mushrooms. This substrate gave the highest value in the number of yields, mass, size, and height with a smooth, white, and wide in diameter fan shape cap, overlapping cluster, with slightly course gills running from the cap down below the elongated stem. Notably, the substrate with 100% carbonized palay husks gave no harvest of oyster mushrooms in the entire 30-day period of study). It was also found that the increasing ratio of lye straw in the substrate closely correlates with the number of yields, mass, size, height, texture, and appearance. There is a significant difference between the sterilized palay husk and carbonized palay husk as the fruiting oyster mushroom bag. It was revealed that the sterilized palay husk with lye straw produced a more significant amount of oyster mushroom in yield (piece), mass (gram), and size (cm) compared with carbonized palay husk but there is no significance in terms of height. Since that the production of oyster mushrooms using carbonized palay husk with lye straw was increased in terms of height. Therefore, the hypothesis of this study was partially accepted. It is recommended to utilize of the efficiency of agro-wastes as the substrate in cultivating oyster mushroom. More specifically the 25 % sterilized palay husk with 75 %lye straw. It can harvest more amount oyster mushroom in terms of yields, mass, and size. However, it is more recommended to used 25% carbonized palay husk with 75 % lye straw in terms of height of oyster mushroom.

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.

Dynamics of Fractional Composition of Grain-and-Straw Mass Being Threshed in the Threshing Mechanism of a Combine Harvester

Introduction. The article presents the results of theoretical and experimental studies of threshing and separation processes in the threshing mechanism of the combine harvester with a digital assessment of the fractional composition of the grain-and-straw material being threshed. The obtained data will allow detecting dynamics of fractional composition of grain-and-straw mass being threshed in the threshing gap of the threshing mechanism depending on its supply. Materials and Methods. The research was carried out on a special stand in the form of a separate unit of the combine threshing mechanism. Grain-and-straw samplers were installed under each threshing section. The mass feed was changed from 1.0 to 6.0 kg/s at a straw ratio of 1:1. The obtained data were approximated using a standard procedure. Results. There was determined the amount of grain and straw passed through the threshing section screen and the rest of grain and straw entering the straw separator depending on their initial amount. For each fraction, there were determined the ratio of straw mass to grain mass, the density and thickness of the grain-and-straw heap layer on the shaking board ahead of the grates and at the beginning of the straw separator keys. The dynamics of grain-and-straw separation was identified by scanning the length of the grains with the determination of the density and compression degree of the grain-and-straw mixture layer in the threshing gap. Discussion and Conclusion. It was found that in the heap of grain-and-straw passed through a threshing section, the ratio of straw mass to grain mass decreases from 0.46 to 0.27 and density increases from 60.1 to 84.0 kg/m3. In the heap of grain-and-straw that fell on the straw separator, the ratio of the straw mass to the grain mass decreases from 11.2 to 2.0, the density increases within a small range from 21.7 to 26.4 kg/m3. Thickness of the heap layer on the shaking board in front of the cleaning sieves varies in the range 0.25‒10.20 cm, and on the straw walker ‒ 2.2‒19.8 cm when changing the supply of the total mass for threshing from 1 to 6 kg/s.

Bioconversion of Agricultural Wastes into a Value-Added Product: Straw of Norwegian Grains Composted with Dairy Manure Food Waste Digestate in Mushroom Cultivation

Commercial mushroom production is based on composted locally available agro-industrial wastes rich in carbon and nitrogen such as wheat straw supplemented with chicken manure. Either component can be replaced by other kinds of grain straw: barley, oat, or a mixture of different straw types and combined with diary manure—food waste digestate after anaerobic biogas digestion. Original, unseparated liquid digestate is nutritious, rich in nitrogen and organic matter. This research aimed to investigate the effect of digestate and different straw ratios on the composting process and productivity and their consequent effect on mushroom cultivation parameters of Agaricus subrufescens. All investigated experimental mushroom compost (EMC) types worked well during the composting process, reaching the desired moisture of 65–75%, N content of 1.43–1.93%, and a C/N ratio ranging from 21.5 to 29.1, supporting growth of mycelium and producing mushrooms. Supplementation with barley straw resulted in better EMC structure with the highest yield and biological efficiency (BE) (157.9 g kg−1; 64%), whereas oat addition gave the lowest yield and BE (88.6 g kg−1 and 38%). Precociousness (yield at mid-cycle of the crop development) was higher for oat substrates (68.9%), while earliness (days to harvest from casing) was lower for barley EMC.

Effect of molasses on fermentation quality of wheat straw ensiled with perennial ryegrass

Context Insufficient supply of silage has limited the development of animal husbandry in Tibet, where natural pasture may not meet requirements. Although wheat (Triticum aestivum L.) straw could be a supplementary forage, it is difficult to ensile. Mixing perennial ryegrass (Lolium perenne L.) and adding molasses may help to facilitate successful ensilage. Aims The objectives were to determine the proper mixing ratios of wheat straw and perennial ryegrass for silage, and to evaluate the effects of different levels of molasses on fermentation quality. Methods In Experiment 1, wheat straw was ensiled without perennial ryegrass or mixed at ratios of 4:1, 3:2 and 2:3 (fresh-weight basis). Fermentation quality was evaluated when the laboratory silos were opened after 7, 14, 30 and 60 days. In Experiment 2, a mixture of wheat straw and perennial ryegrass (2:3) was treated with 0%, 3%, 4% and 5% molasses (fresh-weight basis) and ensiled. Fermentation quality was determined at 7, 14, 30 and 60 days. Key results In Experiment 1, inclusion of perennial ryegrass significantly (P &lt; 0.05) increased lactic acid and water-soluble carbohydrate contents and the lactic acid:acetic acid ratio, and significantly (P &lt; 0.05) decreased pH and contents of ammonia-nitrogen, acetic acid, butyric acid and total volatile fatty acids. The 2:3 mixture of wheat straw ensiled with perennial ryegrass was judged the best, with the highest lactic acid content and lowest pH and butyric acid content (P &lt; 0.05). In Experiment 2, molasses addition significantly (P &lt; 0.05) increased lactic acid, water-soluble carbohydrate and dry matter contents, and significantly (P &lt; 0.05) decreased pH and ammonia-nitrogen content compared with the control. Trace amounts of propionic and butyric acids were observed in all silages. Fermentation quality was similar among all treatments with added molasses. Conclusions Considering the costs of additives, 3% molasses was most suitable for practical application when ensiling wheat straw with perennial ryegrass at an optimum ratio of 2:3. Implications This work may help to inform producers on efficient utilisation of wheat straw for silage making by demonstrating successful ensiling with perennial ryegrass and added molasses.

Effects of cow manure ratios on methane production and microbial community evolution in anaerobic co-digestion with different crop wastes

The present study investigated the effects of cow manure ratios mixed with maize stover, rice straw, and wheat stalk at 3, 2, 1 (total solid based, TS-based), respectively, on methane production and microbial community structure during the anaerobic co-digestion process. Results showed cow manure co-digested with maize stover, wheat stalk, and rice straw at ratios of 2, 1, and 3 had the highest cumulative methane yields (272.99, 153.22 167.73 mL/g volatile solid (VS), respectively) and better stability (e.g. pH, volatile fatty acids (VFAs) and their component). The main microbe evolution had a similar trend which was Petrimonas and Methanosaeta in the early digestion process (Days 0-7) and then evolved into Longilinea, Ruminofilibacter, and Methanosarcina with the progress of digestion, but the relative abundance of these microbes in each reactor was different. It was worth noting that Caldicoprobacter in cow manure to maize stover ratio of 2, and to rice straw ratio of three reactors had a relatively higher proportion than reactor of cow manure to wheat stalk ratio of 1, and Hydrogenophaga was the specific bacterium in cow manure to wheat stalk ratio of 1 reactor. In addition, Petrimonas showed positive relationship with VFAs and Longilinea was the opposite. Methanosaeta and Methanobacterium contributed the most during the peak period of methane production in cow manure and maize stover co-digested reactor, and showed positive relationship with acetic acid. However, Methanosarcina and Methanospirillum made a great contribution during the peak period of methane production in cow manure co-digested with wheat stalk and rice straw reactors. These findings could provide further information on the application of cow manure co-digested with crop wastes. Keywords: cow manure ratio, methane production, microbial community evolution, crop wastes, anaerobic co-digestion DOI: 10.25165/j.ijabe.20221505.7148 Citation: Hao J J, Jia S F, Sun H, Chen G P, Zhang J X, Zhao Y B, et al. Effects of cow manure ratios on methane production and microbial community evolution in anaerobic co-digestion with different crop wastes. Int J Agric & Biol Eng, 2022; 15(5): 219–228.

Influence of corn straw on distribution and migration of nitrogen and heavy metals during microwave-assisted pyrolysis of municipal sewage sludge

This study explored pyrolysis characteristics, nitrogen transformation and migration of heavy metals during microwave-assisted pyrolysis of municipal sewage sludge in a continuously operated auger pyrolyser at different temperatures and corn straw ratios. The results showed higher temperatures and more corn straw resulted in more gas yield (e.g., CO2, CO, CH4 and H2) and less char yield. 5 wt% corn straw addition at 750 °C achieved high-quality bio-oil with less O-containing compounds, which was more favorable for upgrading to transportation fuels. Sludge chars prepared at higher corn straw ratios had lower ratios of H/C and N/C, and higher carbon content. Nitrogen transformation pathways and mechanisms were investigated. The residual ratio of heavy metals (except Cd) in sludge char was 67.74–100%. However, the residual ratio of Cd decreased significantly to 6.46% at 750 °C. Concentrations of all heavy metals in sludge char conformed to national standard (CJ/T 362-2011, China), and the potential ecological risk was slight. Sludge chars prepared in the presence of corn straw had lower ecological risk and higher retention capacity of heavy metals (e.g., Pb, Cr, Mn, Cu, Zn, and Ni) compared with pyrolysis of sewage sludge.

Preparation of Ni-La/Al2O3-CeO2-Bamboo Charcoal Catalyst and Its Application in Co-pyrolysis of Straw and Plastic for Hydrogen Production

The conversion of biomass and plastic into hydrogen through catalytic pyrolysis is a promising technology for the production of clean fuels. The developed Ni-La/Al2O3-CeO2-Bamboo charcoal (ACB) catalyst was applied to the co-pyrolysis of straw and polyethylene (PE) to produce hydrogen. This research explored the optimal mixing ratio of straw and PE, and the influence of the presence and stability of the catalysts on hydrogen production. Experiments show that the best mixing ratio is 5:5. Ni-La/ACB can significantly promote the production of H2 (13.56 mmol/g), and it can still maintain high stability after repeated use, which is inseparable from the introduction of La to improve the performance of the catalyst. It can be concluded that adding a certain proportion of plastic is beneficial to increase H2 production, and co-pyrolysis can solve the pollution problem caused by improper treatment of plastics while making full use of renewable energy.

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.

Anaerobic Fermentation of Combined Chicken Manure and Straw on a Sequencing Batch Reactor: Analysis of Stability and Numerical Modeling

Anaerobic fermentation experiments were performed using combinations of chicken manure and straw at a temperature of 37±0.5 °C for 70 d. In this investigation, system stability and methane production were analyzed using the Logistic model. According to our results, the highest cumulative methane yield was 292.87 mL/g VS at a straw ratio of 3%. This value was 17.43% higher than the one obtained using pure chicken manure. In addition, a positive correlation between ammonia concentration and content of chicken manure was observed. At the end of the reaction, pH values in the four groups were between 7.0 and 8.0. However, pH in the M2 group was significantly higher than that observed in the rest of the groups. Data also indicated that hydrolase activities were positively correlated with SCOD concentrations. In this context, cellulase activity reached the highest value on day 40. Proteinase activity presented two peaks on days 20 and 40. In the case of lipase, activities and amylase initially increased and later decreased, but the change is small. According to the results of the Logistic model, the highest methane production potential was of 404.41 mL/g VS, at a straw proportion of 3%. In addition, the highest daily methane yield was 6.13 mL/g VS.

Parameter Optimization of a Potted Seedling Tray Prepared from a Mixture of Rice Straw and Fermented Cow Manure Using the Response Surface Methodology.

Biomass is generally regarded as a significant renewable resource, which can be used as the raw material for bioproducts. In the study, a mixture of rice straw and fermented cow manure was utilized to produce potted seedling trays, which are biodegradable and environmentally friendly. The effects of process parameters on the quality of final products were assessed by measuring damage resistance (DR) and expansion ratio (ER). Single-factor experiments and the response surface methodology (RSM) were used to optimize process parameters, including moisture content, forming pressure, mass percentage of straw (the ratio of rice straw to the mixture), and forming temperature as variables, and DR and ER of potted seedling trays as responses. The results showed that moisture content had the largest effect on DR and ER, followed by forming pressure, forming temperature, and mass percentage of straw. The optimal conditions were identified as a moisture content of 13%, forming pressure of 124 kN, mass percentage of straw equal to 8%, and forming temperature of 132 °C. There was a good agreement between the experimental data and the predicted results, indicating the reliability of the optimization process. Under the optimal conditions, the effectiveness of the regression model was further validated by the desirability of 0.97. Our findings shed new light on the perfect utilization of straws and animal manure and provided a reliable reference for the preparation of potted seedling trays from other types of biomass produced by agriculture.