Anaerobic co-digestion of sodium hydroxide pretreated sugarcane leaves with pig manure and dairy manure

Sugarcane leaves(SL)pretreated by alkali was used as substrate to enhance biogas production via mesophilic anaerobic digestion(AD)in this study.Effectiveness of different concentrations of NaOH pretreatment on AD performance was investigated.Results showed that compared to untreated sample of SL,the lignocellulose(LCH)content of NaOH pretreated group was decreased by 5.79%-16.85%.However,the cumulative biogas production of the pretreated samples increased in the range of 34.54%-82.67%;moreover,T90 was shorten by 5-7 d.The highest anaerobic digestibility of SL was achieved at 6%NaOH pretreatment,which produced 287.30 mL/g TS of biogas.A significant interactive effect of the three parameters(temperature,SL/manure mixing ratio and C/N ratio)was found on the biogasification of anaerobic co-digestion,and a maximum biogas production was achieved at 36.2oC,mixing ratio of 1.6 and C/N ratio of 29.2.These show that the verification experiment confirmed the optimization results.This study provides meaningful insight for exploring efficient pretreatment strategy and optimal condition to stabilize and enhance AD performance for practical application.

Conversion of Sugarcane Shoots and Leaves into Reducing Sugars by Pretreatment and Enzymatic Hydrolysis

Sugarcane shoots and leaves consist of 38% cellulose, 30.6% hemicellulose and 12.8% lignin on dry solid （DS） basis and have the potential to serve as low cost feedstocks for ethanol production. The pretreatment and enzymatic hydrolysis conditions include particle size, alkali （NaOH）/dilute acid （H2SO4） pretreatment, chemical and substrate concentrations, temperature, autoclaving time for pretreatment, enzyme concentration, pH and temperature for hydrolysis varied were evaluated for conversion of sugarcane shoots and leaves cellulose and hemicellulose to reducing sugar. The optimum conditions were accomplished by using 14% w/v DS of 0-10 mm sugarcane shoots and leaves in particle size, pretreated with 1.5% w/v of dilute sulfuric acid at 121℃, 15 lbs/in2 for 15 min and enzymatic saccharification using 40 FPU/g DS cellulose at 50℃ and pH 5, After incubating at 160 rpm for 12 hrs, 59 g/L or 386,38 mg/g DS of reducing sugar and 50.69% saccharification were obtained.

Effect of Different Pretreatment Methods on Enzymatic Saccharification and Ethanol Production from Sugarcane Shoots and Leaves

Sugarcane shoots and leaves consist of 35.2% cellulose, 23.43% hemicellulose, 12.6% lignin and 6.59% ash on dry solid （DS） basis and have the potential to serve as low cost feedstocks for ethanol production. To improve the enzymatic digestibility of these biomass and bioethanol production, three pretreatment methods had been investigated and compared, including： （1） 2% w/v NaOH solution autoclaving pretreatment; （2） 2% w/v H2SO4 solution autoclaving pretreatment and （3） two steps of 2% w/v NaOH solution autoclaving followed by 2% w/v H2SO4 solution autoclaving pretreatment. Among them, the best result for ethanol production was obtained when 15 g DS of sugarcane shoots and leaves was pretreated by using two step of 2% w/v NaOH solution autoclaving followed by 2% w/v H2SO4 solution autoclaving. The highest ethanol concentration 30.40 g/L （92.65% in fermentation efficiency） was obtained from reducing sugar 89.25 g/L at 48 h. Moreover, the washing step of solid residue after pretreatment could reduce furfural and hydroxymethylfurfural （HMF） in all pretreatment methods when compared to unwashing solid residue after pretreatment.

Design and Analysis on Compression Mechanism of Small Square Bales of Sugarcane Leaf Baler

With more and more attention paid to comprehensive utilization of agricul-tural biomass resources, environment pol ution caused by large-scale burning of sug-arcane leaves can be effectively avoided, and it is urgent to resolve storage issue of sugarcane leaf. Through referring to the relevant domestic baler models and re-search findings, preliminary design and analysis were conducted on key components compression mechanism of smal sugarcane leaf baler, involving the open compres-sion principle for sugarcane leaf square baler, determination of the crank slider-type compression mechanism and the main parameters such as crank length, compres-sion frequency, feed rate and feed inlet length. Based on SolidWorks software, this paper established the 3-dimensional models of slider-crank type compression mech-anism, and imported it into ADMAMS software for the motion simulation analysis, to establish the foundation for the design and manufacture of subsequent smal sugar-cane leaf square baler prototype.

Moving-window bis-correlation coefficients method for visible and near-infrared spectral discriminant analysis with applications

The moving window bis corelation coefficients(MW BiCC)was proposed and employed for the discriminant analysis of transgenic sugarcane leaves and B-thalassemia with visible and near-infrared(Vis NIR)spectroscopy.The well-performed moving window principal component analysis linear discriminant analysis(MWPCA-LDA)was also conducted for comparison.A total of 306 transgenic(positive)and 150 nont ransgenic(negative)leave samples of sugarcane were collected and divided to calibration,prediction,and validation.The diffuse reflection spectra were corected using Savitzky-Golay(SG)smoothing with first-order derivative(d=1),third-degree polynomial(p=3)and 25 smpothing points(m=25).The selected waveband was 736-1054nm with MW-BiCC,and the positive and negative validation recognition rates(V_REC^(+),VREC^(-))were 100%,98.0%,which achieved the same effect as MWPCA-LDA.Another example,the 93 B-thalassemia(positive)and 148 nonthalassemia(negative)of human hemolytic samples were colloctod.The transmission spectra were corrected using SG smoothing withd=1,p=3 and m=53.Using M W-BiCC,many best wavebands were selected(e.g.,1116-1146,17941848 and 22842342nm).The V_REC^(+)and V_REC^(-)were both 100%,which achieved the same effect as MW-PCA-LDA.Importantly,the BICC only required ca lculating correlation cofficients between the spectrum of prediction sample and the average spectra of two types of calibration samples.Thus,BiCC was very simple in algorithm,and expected to obtain more applications.The results first confirmed the feasibility of distinguishing B-thalassemia and normal control samples by NIR spectroscopy,and provided a promising simple tool for large population thalassemia screening.