scholarly journals BIOMETHANE POTENTIAL (BMP) OF ARROWROOT POWDER PROCESSING WASTE AND EFFECT OF ALKALINE PRE-TREATMENT

2018 ◽  
Vol 56 (2C) ◽  
pp. 171-177
Author(s):  
Nguyen Pham Hong Lien

Arrowroot waste has been being discharged without treatment in powder/starch processing villages in Viet Nam causing serious environmental problem. This waste is degradable and might have good Biomethane Potential (BMP) which leads to a possibility to treat them by anaerobic digestion. Therefore, the study aimed to find out the BMP of the waste and to find out if alkaline pre-treatment would improve it. Solid waste from arrowroot powder processing was collected in Duong Lieu village, Ha Noi, and different samples were going through BMP test: the untreated sample and NaOH pre-treated samples at different NaOH dose from 3 to 9 wt. % (dry weight based). BMP was determined in 590 mL bottles at 37 oC for 50 days. As the results, BMP of the original arrowroot waste sample was 253 NmLCH4/gVS and alkaline pretreatment increased BMP of the waste 21.9 % at 7 % NaOH. The reduction of lignin content and hemicellulose content at this pretreatment were 7.2 % and 9.4 %, respectively. The results show that the waste has potential for methane recovery and alkaline pre-treatment by NaOH would slightly improve its biodegradability. 

Cassava starch processing industry produces cassava pulp as a by-product or waste. In the well-known Duong Lieu village, this waste is released in surrounding environment without treatment causing serious environmental problems. The study aimed to (1) determine the Biomethane Potential (BMP) of the waste and to (2) find out if alkaline pre-treatment would improve it. Different cassava pulp samples were going through BMP test: untreated sample; pre-treated samples at different NaOH doses of 2, 6, 8 wt.% (dry weight-based) and pre-treated samples at different NaHCO3 doses of 2, 4, 6, 8 wt.% (dry weight based). BMP assays were conducted in 590mL bottles at 37oC for 40 days. As the result, BMP of the untreated waste was 281 NmLCH4/gVS and alkaline pretreatment increased BMP of the waste up to 479 mLCH4/gVS by treatment with NaOH 6 wt.% and 450 mLCH4/gVS by treatment with NaHCO3 6 wt.%. In addition, there was a significant reduction of lignin content of the substrate after alkaline pre-treatment. The results show that cassava pulp waste has moderate potential for biogas recovery. In addition, alkaline pre-treatment by either NaOH or NaHCO3 would significantly improve its BMP, possibly thanks to the reduction of lignin content.


2021 ◽  
Vol 924 (1) ◽  
pp. 012071
Author(s):  
N A Rohma ◽  
S Suhartini ◽  
I Nurika

Abstract Production of biogas from lignocellulosic biomass by anaerobic digestion (AD) has attracted much interest. Oil palm empty fruit bunches (OPEFB), one of lignocellulosic biomass, is highly abundant in Indonesia and has potential as feedstock for bioenergy production such as biogas or methane. Yet, pre-treatments are needed to improve biogas production due to its complex crystalline structures. Chemical pre-treatments with acid or alkaline solution were reported to increase cellulose or highly reduce the lignin content of OPEFB. This study aimed to evaluate the effect of acid and alkaline pre-treatments on the characteristics of OPEFB and methane potential. The acid pre-treatment experimental design was used factor of H2SO4 concentration (1, 1.3, and 1.6 (%v/v)) and NaOH concentration (1.8, 2.8, and 3.8 (%w/v)). Methane potential evaluation was carried out using the biochemical methane potential (BMP) test with the Automatic Methane Potential Test System (AMPTS) II under mesophilic condition (37°C), operated for 28 days. The results showed that both dilute acid and alkaline pre-treatment positively impact altering the characteristics of OPEFB, hence the specific methane potential. Alkaline pre-treatment with NaOH 3.8 (%w/v) gave the highest average SMP value of 0.161 ± 0.005 m3 CH4/kgVSadded.


1984 ◽  
Vol 35 (2) ◽  
pp. 115 ◽  
Author(s):  
DJ Mares

Germinability in harvest-mature wheat grain showed a marked dependence on temperature. The optimum temperature for the complete germination of all grains ranged from 20�C for the non-dormant variety, Timgalen, to 10�C for the strongly dormant red wheat RL 4137, whereas the optimum in terms of the shortest lag period ranged from 25� to 15�C for the same varieties. Germinability gradually increased during post-harvest storage and, for after-ripened grain, the optimum temperature for both complete germination and shortest lag period were greater than 30�C. Germinability could also be increased by pre-treating imbibing grains at temperatures of 5�, 10� or in some cases 15�C. This treatment was only effective for grain at moisture contents >25% (dry weight) and the effect was not reversed by redesiccation. The pre-treatment temperature required for maximum germinability decreased with increasing levels of grain dormancy. Complete removal of dormancy required a pre-treatment period of c. 48 h; however, lesser periods gave the shortest lag period in the case of the dormant varieties. The implications of these results for the utilization of dormancy in the development of preharvest sprouting damage tolerant varieties and their subsequent use in practice are discussed.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Leilah Krounbi ◽  
Akio Enders ◽  
John Gaunt ◽  
Margaret Ball ◽  
Johannes Lehmann

AbstractThe conversion of dairy waste with high moisture contents to dry fertilizers may reduce environmental degradation while lowering crop production costs. We converted the solid portion of screw-pressed dairy manure into a sorbent for volatile ammonia (NH3) in the liquid fraction using pyrolysis and pre-treatment with carbon dioxide (CO2). The extractable N in manure biochar exposed to NH3 following CO2 pre-treatment reached 3.36 g N kg−1, 1260-fold greater extractable N than in untreated manure biochar. Ammonia exposure was 142-times more effective in increasing extractable N than immersing manure biochar in the liquid fraction containing dissolved ammonium. Radish and tomato grown in horticultural media with manure biochar treated with CO2 + NH3 promoted up to 35% greater plant growth (dry weight) and 36–83% greater N uptake compared to manure biochar alone. Uptake of N was similar between plants grown with wood biochar exposed to CO2 + NH3, compared to N-equivalent treatments. The available N in dairy waste in New York (NY) state, if pyrolyzed and treated with NH3 + CO2, is equivalent to 11,732–42,232 Mg N year−1, valued at 6–21.5 million USD year−1. Separated dairy manure treated with CO2 + NH3 can offset 23–82% of N fertilizer needs of NY State, while stabilizing both the solid and liquid fraction of manure for reduced environmental pollution.


2017 ◽  
Vol 13 (3) ◽  
pp. 1-9
Author(s):  
Yasmeen Salih Mahdi ◽  
Asem Hassan Mohammed ◽  
Alaa Kareem Mohammed

Abstract   In this study, modified organic solvent (organosolv) method was applied to remove high lignin content in the date palm fronds (type Al-Zahdi) which was taken from the Iraqi gardens. In modified organosolv, lignocellulosic material is fractionated into its constituents (lignin, cellulose and hemicellulose). In this process, solvent (organic)-water is brought into contact with the lignocellulosic biomass at high temperature, using stainless steel reactor (digester). Therefor; most of hemicellulose will remove from the biomass, while the solid residue (mainly cellulose) can be used in various industrial fields. Three variables were studied in this process: temperature, ratio of ethanol to water and digestion time. Statistical experimental design type Central Composite Design (CCD) has been used to find a mathematical relationship between the variables and the remaining lignin percent as dependent variable. The results obtained in this study were represented by a polynomial mathematical equation of the second degree.  The results showed that the best digestion time was (80 minutes), which gave the best percent remaining concentration of lignin (3%) at temperature of 185oC and ratio of ethanol: water equal to 50: 50 wt/wt. In order to reduce digesting time, the effect of using different catalysts have been studied such as (NaOH, H2SO4, Ca (OH) 2) at low concentration (0.025, 0.025, 0.05M) respectively. It was found that the best catalyst is sodium hydroxide at concentration (0.025) mol/L which gave the same percent of  lignin 3% but with low digestion time about 30 min. Keywords: Biomass pre-treatment, delignification, lignin, organosolv, date palm fronds.


Author(s):  
Ding-Yuan Chen ◽  
Axel R Persson ◽  
Kai Hsin Wen ◽  
Daniel Sommer ◽  
Jan Gruenenpuett ◽  
...  

Abstract The impact on the performance of GaN HEMTs of in situ ammonia (NH3) pre-treatment prior to the deposition of silicon nitride (SiN) passivation with low-pressure chemical vapor deposition is investigated. Three different NH3 pre-treatment durations (0, 3, and 10 minutes) were compared in terms of interface properties and device performance. A reduction of oxygen at the interface between SiN and epi-structure is detected by Scanning Transmission Electron Microscopy-Electron Energy Loss Spectroscopy measurements in the sample subjected to 10 minutes of pre-treatment. The samples subjected to NH3 pre-treatment show a reduced surface-related current dispersion of 9 % (compared to 16% for the untreated sample), which is attributed to the reduction of oxygen at the SiN/epi interface. Furthermore, NH3 pre-treatment for 10 minutes significantly improves the current dispersion uniformity from 14.5 % to 1.9 %. The reduced trapping effects result in a high output power of 3.4 W/mm at 3 GHz (compared to 2.6 W/mm for the untreated sample). These results demonstrate that the in situ NH3 pre-treatment before low-pressure chemical vapor deposition of SiN passivation is critical and can effectively improves the large-signal microwave performance of GaN HEMTs.


Agriculture ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 170 ◽  
Author(s):  
Gerhard Gramss ◽  
Klaus-Dieter Voigt

Crossing annual cereals, legumes, and oilseeds with wild rhizomatous relatives is used to create perennial lines that fruit over 2–3 seasons. Contrary to annual crops, the year-round vegetation cover should contribute to carbon sequestration, soil formation, and root mineral preservation. Soil erosion, nutrient leaching, and labor expenses may be reduced. While deep-rooted grasses actually inhibit nitrate leaching, advantages in nutrient storage and soil formation are not yet shown. Therefore, the turnover of organics and minerals in the perennial goldenrod was compared with that of winter wheat between blooming and resprouting (28 February) by gravimetry and ICP-MS. From blooming (23 August) to harvest (13 November), goldenrod stalks of 10,070 (given in kg ha−1) lost 23% by dry weight (DW) and released 14.9/9.6/65.7 in NPK and 2193 in water-soluble organics via leaching and root exudation. Apart from a transient rise of 28.8 in N around 13 November, the stubble/rhizome system held CaKMg(N)P stable at a level avoiding metal stress from 23 August to 28 February. Filling seeds in wheat excluded net losses of minerals and organics from anthesis to harvest (23 July). Stubbles (16 cm) and spilt grains of 2890 represented 41.8/2.91/62.5 in NPK and lost 905 in biomass with 25.4/1.8/59.8 in NPK to the soil by 28 February. In wheat-maize rotations, ploughing was avoided until early March. Weeds and seedlings emerged from spilt grains replaced losses in stubble biomass, N, and P but left 40.5 in K unused to the soil. In wheat-wheat rotations, organics and minerals lost by the down-ploughed biomass were replenished by the next-rotation seedlings that left only 18.3 in K to the soil. In summary, off-season goldenrod rhizomes did not store excess minerals. The rate of mineral preservation corresponded with the quantity of the biomass irrespective of its perennial habit. Released water-soluble organics should foster microbial carbon formation and CO2 efflux while soil improving gains in humate C should depend on the lignin content of the decaying annual or perennial biomass. Clues for NPK savings by perennials were not found.


1998 ◽  
Vol 23 (1) ◽  
pp. 170-172
Author(s):  
Arthur A. Hower ◽  
Paul Rebarchak

Abstract Two tests were conducted to evaluate the efficacy of insecticides against potato leafhopper. The experiments were conducted at the Russell E. Larson Agricultural Research Center at Rock Springs, Centre County, PA on a second-year (first full harvest year) alfalfa (Pioneer 5373) crop. Plots of 40 X 40 ft were arranged in a RCB design with an untreated check in each of four replications. Potato leafhopper densities were estimated from 20 pendulum sweeps of a 15-inch-diam insect beating net taken randomly across each plot. Prior to treatment, potato leafhopper densities were estimated on 9 Jun (Experiment 1). Due to inclement weather, a pre-treatment sweep was not taken for Experiment 2. With the exception of LABS 116 in Experiment 1, all insecticide treatments were applied as foliar sprays on 16 Jun (Experiment 1) and 25 Jul (Experiment 2). LABS 116 was applied in Experiment 1 on 17 Jun as a result of needing an additional product shipment. Cygon 4E was added as a standard insecticide treatment in both Experiments. Alfalfa height at application was 4-6 inches. Insecticides were applied in 25 gal of water per acre at 25 psi with a tractor-mounted sprayer equipped with a 20-ft boom containing 80 degree flat fan nozzles and 50 mesh screens. Leafhopper densities were sampled on 19, 23, 30 Jun and 8 Jul (i.e. 3, 7, 14, 22 DAT) for Experiment 1, and 25 Jul, and 1, 8, 15, 24 Aug (i.e. 3, 7, 14, 21, 30 DAT) for Experiment 2. Densities reported represent the number of adults, number of nymphs, and the combined numbers of adults and nymphs collected per 20 sweeps. Alfalfa yield was determined on 8 Jul (Experiment 1) and 25 Aug (Experiment 2) from a 60-ft2 swath taken from each plot with a Carter Forage Harvester (Carter Mfg. Co. Inc., Brookston, IN). Percent moisture was determined by oven drying a subsample of alfalfa (approximately 2 lb wet). Alfalfa yield is reported as dry weight lb per acre.


2006 ◽  
Vol 45 ◽  
pp. 1696-1703 ◽  
Author(s):  
Paola Palmero ◽  
Laura Montanaro

The elaboration of 50 vol.% Al2O3/YAG (Y3Al5O12) nanocomposites was pursued by comparing two processing routes. In one case, a composite powder was firstly synthesized via reverse-strike co-precipitation and then submitted to an optimized thermal and extensive milling pre-treatment prior to sinter. In the second case, a pure-alumina precursor was prepared via reverse-strike precipitation and then doped with an yttrium salt solution; such doping procedure was performed on alumina samples submitted to several thermal and/or mechanical pre-treatments carried out to yield more or less relevant α-phase amounts. The optimization of the thermal/mechanical pre-treatment of the former powder led to a very homogeneous, dense and fine microstructure, made of α-alumina and YAG grains of about 300 nm in size. On the contrary, sintered bodies characterised by a larger mean grain size and a lower homogeneity in microstructure were obtained by using the second starting powder, even if, also in this case, a suitable control of the powder processing can allow a promising improvement of the microstructural features.


1997 ◽  
Vol 48 (2) ◽  
pp. 147 ◽  
Author(s):  
G. M. Smith ◽  
C. L. White

We determined the effects of increased dietary concentrations of molybdenum and sulfur on the accumulation and tissue concentrations of cadmium in sheep, and compared them with effects on copper. Forty sheep, each weighing approximately 40 kg, were adjusted for 3 weeks to a basal diet of 80% wheaten chaff and 20% lupin seed containing (per kg dry weight) 0·016 mg Cd, 0·45 mg Mo, 3·4 mg Cu, and 1·9 g S. On Day 0 of treatment, 8 sheep were killed and the tissues analysed for trace minerals to provide a baseline value. The remaining sheep were divided into 4 dietary treatment groups: control (basal diet plus 4 mg Cd/kg), +Mo (control diet plus 15 mg Mo/kg), +S (control diet plus 4 g S/kg), +Mo+S (control diet+15 mg Mo+4 g S/kg). The treatment period lasted 80 days, after which sheep were killed for tissue samples. Sulfur alone reduced the accumulation of Cd in liver, kidney, and muscle by 60% compared with control sheep (P < 0·05). Molybdenum alone reduced Cd accumulation by 40% in liver and muscle (P < 0·05) and 30% in kidney (P = 0·09). When provided together (+Mo+S), the effect was equivalent to feeding with Mo alone, showing that Mo blocked the effect of S. Cadmium concentrations in whole kidneys for the 4 respective treatments were 6·40 ± 0· 7, 2·8 ± 0·3, 4·5 ± 0·8, and 5·0 ± 0·5 mg/kg fresh weight. The pre-treatment concentration was 0·7 ± 0·2 mg/kg. For Cu in blood and tissues, the effects of Mo and S treatment were consistent with the thiomolybdate hypothesis, and were quite different from those seen for Cd. Copper concentrations in whole kidney for the 4 treatments were 4·1 ± 0·1, 3·5 ± 0·2, 4·7 ± 0·3, and 22·4 ± 3·9 mg/kg fresh weight. The pre-treatment concentration was 4·1 ± 0·3 mg/kg. The results show that increased dietary levels of Mo and S reduce the accumulation of Cd in tissues, and the mechanisms of action differ from those involving Cu.


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