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1.
Determination of nitrous oxide, methane, and ammonia emissions from a swine waste composting process 总被引:7,自引:0,他引:7
Takashi Osada Kazutaka Kuroda Michihiro Yonaga 《Journal of Material Cycles and Waste Management》2000,2(1):51-56
The amounts of harmful gas emissions from the process of composting swine waste were determined using an experimental composting
apparatus. Forced aeration (19.2–96.1 l/m3/min) was carried out continuously, and exhaust gases were collected and analyzed periodically. With weekly turning and the
addition of a bulking agent in order to decrease the moisture content and increase air permeability, the temperature of most
of the contents rose to 70°C and composting was complete within 3–5 weeks. NH3, CH4, and N2O emissions were high in the early stage of composting. About 10%–25% of the nitrogen in the raw material was lost as NH3 gas during composting. The emission rate of NH3 mainly depended on the aeration rate, so that as the aeration rate rose, the level of NH3 emissions increased. The CH4 and N2O emissions could be kept lower with adequate treatment at more than 40 l/m3/min aeration. N2O may be mainly the result of the denitrification of NO
x
-N in the additional matured compost used as a composting accelerator.
Received: September 11, 1998 / Accepted: November 8, 1999 相似文献
2.
Demetres Briassoulis Epifania Babou Miltiadis Hiskakis 《Journal of Polymers and the Environment》2011,19(2):341-361
The field performance of experimental biodegradable drip irrigation thin wall and regular pipes was investigated through three
sets of full-scale experiments and in the laboratory. These experimental biodegradable drip irrigation systems were produced
through the processing of biodegradable under real soil conditions polymers, Mater-Bi and Bioflex. The mechanical behaviour
of the biodegradable thin wall pipes during the irrigation period was more unstable when compared to the corresponding behaviour
of the rigid pipes. The tensile strength of the Mater-Bi and Bioflex thin wall pipes remained almost constant during the total
exposure time, except from the folding areas. During the first 7–23 days of exposure in the field, the thin wall pipes had
already lost more than the 50% of their initial elongation at break value due to degradation. However, their hydraulic performance
began to decline only after a period of 100–120 days with the simultaneous formation of the first cracks. Likewise, the majority
of the series of biodegradable rigid pipes exhibited a remarkable reduction in their elongation at break values in the transverse
direction within the first 2 weeks. Despite the significant drop of the elongation at break, all biodegradable rigid pipes
generally retained their tensile strength as well as a satisfactory hydraulic performance during almost the whole duration
of their exposure. A few premature leakages in some points adjoining the drippers were observed after 8–10 weeks of exposure. 相似文献
3.
Neslihan Akdeniz Jacek A. Koziel Hee-Kwon Ahn Thomas D. Glanville Benjamin P. Crawford 《Waste management (New York, N.Y.)》2010,30(10):1981-1988
Emergency mortality composting associated with a disease outbreak has special requirements to reduce the risks of pathogen survival and disease transmission. The most important requirements are to cover mortalities with biosecure barriers and avoid turning compost piles until the pathogens are inactivated. Temperature is the most commonly used parameter for assessing success of a biosecure composting process, but a decline in compost core temperature does not necessarily signify completion of the degradation process. In this study, gas concentrations of volatile organic compounds (VOCs) produced inside biosecure swine mortality composting units filled with six different cover/plant materials were monitored to test the state and completion of the process. Among the 55 compounds identified, dimethyl disulfide, dimethyl trisulfide, and pyrimidine were found to be marker compounds of the process. Temperature at the end of eight weeks was not found as an indicator of swine carcass degradation. However, gas concentrations of the marker compounds at the end of eight weeks were found to be related to carcass degradation. The highest gas concentrations of the marker compounds were measured for the test units with the lowest degradation (highest respiration rates). Dimethyl disulfide was found to be the most robust marker compound as it was detected from all composting units in the eighth week of the trial. Concentration of dimethyl disulfide decreased from a range of 290–4340 ppmv to 6–160 ppbv. Dimethyl trisulfide concentrations decreased to a range of below detection limit to 430 ppbv while pyrimidine concentrations decreased to a range of below detection limit to 13 ppbv. 相似文献
4.
N. Serramiá M.A. Sánchez-Monedero A. Fernández-Hernández C. García-Ortiz Civantos A. Roig 《Waste management (New York, N.Y.)》2010,30(10):1939-1947
One of the main disadvantages in the composting of two-phase olive mill wastes (TPOMW) is the long time required for its transformation (up to 40 weeks). The aim of this work was to evaluate the relationship between the degradation of the lignocellulosic fraction of TPOMW and the organic matter (OM) mineralisation rate in four composting piles prepared with different bulking agents and N-sources used to enhance OM degradation. The kinetics of degradation of the lignocellulosic fraction was compared to conventional maturation and stability indices to evaluate its impact on the duration of the composting process. The composition of bulking agents mainly affected the water-soluble fraction which influenced the OM degradation rate (linear or exponential OM degradation pattern) at early stages of the composting process but it neither modified the duration of the process (between 34 and 36 weeks) nor the total OM degradation underwent by the piles. The high initial mineral N availability was a key factor to significantly enhanced microbial activity. The mixture with urea as N-source registered the most efficient degradation of hemicellulose, cellulose and lignin, reducing the thermophilic phase and the total duration of TPOMW composting. 相似文献
5.
R. Yañez P. Bueno A. Rivera A. García-Barneto M.J. Díaz 《Waste management (New York, N.Y.)》2010,30(5):755-763
Organic matter stabilization resulted from the decrease of cellulose, xylan, arabinan, acetyl groups, glucuronic acids, galacturonic acids (easily biodegradable fractions) and the increase of lignin (resistant compound) and humic substances coming from the initial wastes have been studied. A central composite experimental design was used to investigate the influence of environmental composting parameters (moisture, aeration and particle size) on organic matter evolution. The organic matter evolution was clearly influenced by the studied composting parameters. All results were concordant, with an increase of humic substances and lignin and a decrease of the rest of the cellulose and hemicellulose compounds. Lower cellulose, xylan, acetyl groups and glucuronic acids contents (higher degradation) have been observed under low particle size (1 cm) and higher moisture content (70%). However lower lignin and higher humic substances under medium (3 cm) to low particle size and low moisture content (40%) have been found. 相似文献
6.
7.
Verónica P. Martino Eric Pollet Luc Avérous 《Journal of Polymers and the Environment》2011,19(4):819-826
The swelling capability of chitosan was explored in order to use water both, as volatile plasticizer and as pore-forming agent.
Chitosan powder was swelled in acidic aqueous solution and melt blended with poly(ε-caprolactone) (PCL). After stabilization
at 57% RH and 25 °C, samples suffered a water mass loss of around 30 wt% without dimensions variation. Despite the low miscibility
of these biopolymers, quite homogeneous dispersion of chitosan within the polyester matrix was obtained. Some interactions
between both biopolymers could be observed. To obtain chitosan phase with a thermoplastic-like behaviour, the plasticization
effect was also studied by the addition of 25 wt% glycerol as non volatile plasticizer. The equilibrium moisture content of
samples increased with the incorporation of glycerol due to its hydrophilic nature. Morphology, thermal and mechanical properties
of the blends were determined after stabilization. The preparation of rich PCL blends allowed the formation of macroporous
structures since samples were not contracted after water loss and stabilization. These biomaterials with such a porous structure
could be used for biomedical applications. 相似文献
8.
Marijana Ponjavic Marija S. Nikolic Sanja Jeremic Lidija Djokic Jasmina Nikodinovic-Runic Vladan R. Cosovic Jasna Djonlagic 《Journal of Polymers and the Environment》2018,26(6):2346-2359
Hydrolytic, enzymatic degradation and composting under controlled conditions of series of triblock PCL/PEO copolymers, PCEC, with central short PEO block (M n 400 g/mol) are presented and compared with homopolymer (PCL). The PCEC copolymers, synthesized via ring-opening polymerization of ε-caprolactone, were characterized by 1H NMR, quantitative 13C NMR, GPC, DSC and WAXS. The introduction of the PEO central segment (<?2 wt%) in PCL chains significantly affected thermal degradation and crystallization behavior, while the hydrophobicity was slightly reduced as confirmed by water absorption and moisture uptake experiments. Hydrolytic degradation studies in phosphate buffer after 8 weeks indicated a small weight loss, while FTIR analysis detected changes in crystallinity indexes and GPC measurements revealed bulk degradation. Enzymatic degradation tested by cell-free extracts containing Pseudomonas aeruginosa PAO1 confirmed high enzyme activity throughout the surface causing morphological changes detected by optical microscopy and AFM analysis. The changes in roughness of polymer films revealed surface erosion mechanism of enzymatic degradation. Copolymer with the highest content of PEO segment and the lowest molecular weight showed better degradation ability compared to PCL and other copolymers. Furthermore, composting of polymer films in a model compost system at 37 °C resulted in significant degradation of the all synthesized block copolymers. 相似文献
9.
Effects of bulking agent addition on odorous compounds emissions during composting of OFMSW 总被引:1,自引:0,他引:1
Li-Ming Shao Chun-Yan Zhang Duo Wu Fan Lü Tian-Shui Li Pin-Jing He 《Waste management (New York, N.Y.)》2014,34(8):1381-1390
The effects of rice straw addition level on odorous compounds emissions in a pilot-scale organic fraction of municipal solid waste (OFMSW) composting plant were investigated. The cumulative odorous compounds emissions occurred in a descending order of 40.22, 28.71 and 27.83 mg/dry kg of OFMSW for piles with rice straw addition level at ratio of 1:10, 2:10 and 3:10 (mixing ratio of rice straw to OFMSW on a wet basis), respectively. The mixing ratio of rice straw to OFMSW had a statistically significant effect on the reduction of malodorous sulfur compounds emissions, which had no statistically significant effect on the reduction of VFAs, alcohols, aldehydes, ketones, aromatics and ammonia emissions during composting, respectively. The cumulative emissions of malodorous sulfur compounds from piles with the increasing rice straw addition level were 1.17, 1.08 and 0.88 mg/dry kg of OFMSW, respectively. The optimal mixing ratio of rice straw to OFMSW was 1:5. Using this addition level, the cumulative malodorous sulfur compounds emissions based on the organic matter degradation were the lowest during composting of OFMSW. 相似文献
10.
Takeki Maeda Juzo Matsuda Hiroshi Nakashima Koichi Yoshida Joji Suzuki 《Journal of Material Cycles and Waste Management》2000,2(2):143-149
Over a period of 21 months, we composted food refuse from a student restaurant in Hokkaido University using a commercially
available composting machine. The machine had two reactors, each with a working volume of 250 l. The refuse was mixed with
sawdust in a ratio of 5 l sawdust to 10 kg refuse, and this mixture was fed into the machine daily. We studied the characteristics
of the refuse, the composting mixture, and the finished compost in an effort to optimize the operating parameters. We also
evaluated the effectiveness of the composting process by determining the decomposition rates of the composting materials.
The optimum moisture content of the composting mixture was between 30% wet basis (wb) and 40% wb in this machine. The composting
machine worked well when the first reactor was filled with composting mixture and 0.5 kg lime was added once per week. The
mass of the materials supplied was reduced by 84% over the study period. The decomposition rate of the volatile matter in
all composting materials was 66%. The mass of the food refuse supplied was 14.8 kg/day on average, and the moisture content
of the refuse was 77% wb on average.
Received: October 4, 1999 / Accepted: April 4, 2000 相似文献
11.
Yueqin Yu Lingxiu Liu Yanyan Kong Erchi Zhang Yanping Liu 《Journal of Polymers and the Environment》2011,19(4):926-934
A high-swelling superabsorbent was synthesized with biodegradable N-maleyl chitosan as cross-linker, acrylic acid (AA) and acrylamide (AM) as the monomers, ammonium peroxodisulfate–sodium bisulfite
(NaHSO3) as redox initiation system, by means of aqueous solution polymerization. The best reaction condition was based on the orthogonal
experiment design. The optimal conditions on distilled water absorbency and on 0.9 wt% NaCl solution absorbency were monomer
concentration 20 wt%, mole ratio of AA to (AA + AM) 60%, the neutralization degree of AA 40%, cross-linker concentration 2%
and monomer concentration 25 wt%, mole ratio of AA to (AA + AM) 60%, neutralization degree of AA 50% and cross-linker concentration
1%, respectively. Factors influencing the water absorbency of superabsorbent also were investigated, by single factor experiment
method. The absorbency of superabsorbents in distilled water and 0.9 wt% NaCl solution increased and then decreased with the
increasing of monomer concentration, mole ratio of AA to (AA + AM) and degree of neutralization of AA. With the increasing
of cross-linker concentration, the absorbency in distilled water increased and then decreased, but it decreased all the time
in 0.9 wt% NaCl solution. In enzymatic degradation tests, the weight loss of superabsorbent was related to the content of
cross-linker. 相似文献
12.
Mohammad Taghi Taghizadeh Reza Abdollahi Naser Sadeghpour Orang 《Journal of Polymers and the Environment》2012,20(1):208-216
The degradation of chitosan by means of ultrasound irradiation and its combination with homogeneous photocatalysis (photo-Fenton)
was investigated. Emphasis was given on the effect of additive on degradation rate constants. 24 kHz of ultrasound irradiation
was provided by a sonicator, while an ultraviolet source of 16 W was used for UV irradiation. To increase the efficiency of
degradation process, degradation system was combined with Fe(III) (2.5 × 10−4mol/L) and H2O2 (0.020–0.118 mol/L) in the presence of UV irradiation and the rate of degradation process change from 1.873 × 10−9−6.083 × 10−9 mol1.7 L s−1. Photo-Fenton process led to complete chitosan degradation in 60 min with the rate increasing with increasing catalyst loading.
Sonophotocatalysis in the presence of Fe(III)/H2O2 was always faster than the respective individual processes. A synergistic effect between ultrasound and ultraviolet irradiation
in the presence of Fenton reagent was calculated. The degraded chitosans were characterized by X-ray diffraction (XRD), gel
permeation chromatography (GPC) and Fourier transform infrared (FT-IR) spectroscopy and average molecular weight of ultrasonicated
chitosan was determined by measurements of intrinsic viscosity of samples. The results show that the total degree of deacetylation
(DD) of chitosan change, partially after degradation and the decrease of molecular weight led to transformation of crystal
structure. A negative order for the dependence of the reaction rate on total molar concentration of chitosan solution within
the degradation process was suggested. Results of this study indicate that the presence of catalyst in the reaction medium
can be utilized to reduce molecular weight of chitosan while maintaining the power of irradiated ultrasound and degree of
deacetylation. 相似文献
13.
Jung-Eun Lee 《Journal of Material Cycles and Waste Management》2011,13(3):259-263
Effective handling of municipal digested sludge requires that the product cake have low water content. To this end, we investigated
the change in sludge dewaterability after the addition of fly ash to municipal digested sludge, dewatering of which is difficult
because of its high organic content. The performance of the dewatering is compared with that of electroosmotic dewatering
(EDW) and conventional mechanical dewatering (CMD). Fly ash classified by sieving to the size of 25–75 μm and >75 μm is added
to the municipal digested sludge by 10, 20, and 50 wt% by wet base. When adding fly ash particles to municipal digested sludge,
dewatering efficiency improved with smaller fly ash particle size and with increase in the amount. When sludge was dewatered
using an electroosmotic dewatering method, the dewatering efficiency is improved about 40% by adding fly ash of 25–75 μm particle
size with 20 wt% when compared with conventional mechanical dewatering method without adding the fly ash. It is concluded
that fly ash particles rich in inorganic material are helpful in the dewatering process when added to municipal digested sludge
and EDW is more effective than CDW. 相似文献
14.
Terje Vasskog Ove Bergersen Trude Anderssen Einar Jensen Trine Eggen 《Waste management (New York, N.Y.)》2009,29(11):2808-2815
Sewage and sewage sludge is known to contain pharmaceuticals, and since sewage sludge is often used as fertilizer within agriculture, the reduction of the selective serotonin reuptake inhibitors (SSRIs) Citalopram, Sertraline, Paroxetine, Fluvoxamine and Fluoxetine during composting has been investigated. Sewage sludge was spiked with the SSRIs before the composting experiment started, and the concentration of the SSRIs in the sludge during a 21 day composting period was measured by liquid phase microextraction (LPME) and high-performance liquid chromatography–mass spectrometry. All the SSRIs had a significant decrease in concentration during the composting process. The highest reduction rates were measured for Fluoxetine and Paroxetine and the lowest for Citalopram. In addition three out of four known SSRI metabolites were found in all the samples, and two of them showed a significant increase in concentration during the composting period. 相似文献
15.
Lashermes G Barriuso E Le Villio-Poitrenaud M Houot S 《Waste management (New York, N.Y.)》2012,32(2):271-277
Small-scale reactors (<10 l) have been employed in composting research, but few attempts have assessed the performance of composting considering the transformations of organic matter. Moreover, composting at small scales is often performed by imposing a fixed temperature, thus creating artificial conditions, and the reproducibility of composting has rarely been reported. The objectives of this study are to design an innovative small-scale composting device safeguarding self-heating to drive the composting process and to assess the performance and reproducibility of composting in small-scale pilots. The experimental setup included six 4-l reactors used for composting a mixture of sewage sludge and green wastes. The performance of the process was assessed by monitoring the temperature, O2 consumption and CO2 emissions, and characterising the biochemical evolution of organic matter. A good reproducibility was found for the six replicates with coefficients of variation for all parameters generally lower than 19%. An intense self-heating ensured the existence of a spontaneous thermophilic phase in all reactors. The average loss of total organic matter (TOM) was 46% of the initial content. Compared to the initial mixture, the hot water soluble fraction decreased by 62%, the hemicellulose-like fraction by 68%, the cellulose-like fraction by 50% and the lignin-like fractions by 12% in the final compost. The TOM losses, compost stabilisation and evolution of the biochemical fractions were similar to observed in large reactors or on-site experiments, excluding the lignin degradation, which was less important than in full-scale systems. The reproducibility of the process and the quality of the final compost make it possible to propose the use of this experimental device for research requiring a mass reduction of the initial composted waste mixtures. 相似文献
16.
The degradation of organic compounds found in municipal solid waste (MSW) under the anaerobic landfill conditions produces gas and liquid emissions that can protract well into the landfill after-care period. The European Landfill Directives regulate the amount and nature of the organic compounds disposed into landfills. In South Africa and other developing countries, MSW is still landfilled without any kind of pre-treatment. This paper presents a pilot project of mechanical biological waste treatment (MBWT) in South Africa implemented at municipal level in the city of Durban using passively aerated open windrows. Based on case studies from Austria, England and South Africa, a waste minimisation model which can facilitate full-scale implementation of MBWT in developing countries is presented. MSW was treated in open windrows for 8 weeks. Composting temperature reached a maximum of 65 °C in less than 10 days. The results of eluate tests on waste samples from the windrows at the end of composting show a reduction of BOD5 and BOD5/COD ratios equal to 35.7% and 16.7%, respectively. The percent waste composition of the treated MSW was 28.3% putrescibles, 17.4% garden refuse, 13.3% plastic, 12.4% fabrics, 12% paper and other elements. The waste composition shows that more than 40% of un-treated organic material and also more than 40% non-biodegradable and recyclable materials are still landfilled without any form of biological treatment or resource recovery. A simple wet and dry waste collection model can promote recycling, treatment of biological waste before landfilling, resource recovery, labour intensive jobs and hence sustainable landfilling in the South African scenario as well as in similar developing countries. 相似文献
17.
Nona Merry M. Mitan Mihai Brebu Thallada Bhaskar Akinori Muto Yusaku Sakata Mitsuo Kaji 《Journal of Material Cycles and Waste Management》2007,9(1):62-68
Waste DVDs and CDs were thermally degraded at 450°C by a semibatch process. In total, 40–50 wt% was converted into liquid
product that consisted of phenol derivatives (∼75 wt%), bisphenol (∼10 wt%) and its derivatives, and small amounts of aromatic
hydrocarbons such as benzene, toluene, ethylbenzene, dimethylbenzene, methylethylbenzene, diethylbenzene, and methylisopropyl
benzene. Degradation of the polycarbonate support from DVDs and CDs was enhanced by coprocessing with vegetable cooking oil,
the degradation of which gave a homologue series of hydrocarbons and organic acids with up to 25 and 18 atoms of carbon, respectively.
Silver from the reflective coating on DVDs and CDs remained in the solid residue, its concentration increasing about 2.5 times
compared to that of the original disks. 相似文献
18.
Vinay K. Khatiwala Nilanshu Shekhar Saroj Aggarwal U. K. Mandal 《Journal of Polymers and the Environment》2008,16(1):61-67
The biodegradation behavior of PCL film with high molecular weight (80,000 Da) in presence of bacterium Alcaligenes faecalis and the analysis of degraded polymer film have been carried out. Thin Films of PCL were prepared by means of solution casting
method and the bacterial degradation behavior was carried in basal medium, in presence of bacteria with time variation after
UV treatment. It was observed that after UV treatment the degradation of polymer film was increased and the degradation rate
followed a three steps degradation mechanism. The degraded polymer film was analyzed by means of Differential Scanning Calorimeter
(DSC), Thermo Gravimetric Analyzer (TGA) and Fourier Transform Infrared Spectroscope (FTIR). DSC results revealed that at
the initial stages of the degradation up to 15–20 days, the bacterium preferentially degrades the amorphous parts of the polymer
film over the crystalline zone. Thermo gravimetric analysis highlighted the low temperature stability of degraded films with
extent of degradation. FTIR results showed the chain scission mechanism of the polymer chains and also supported the preferential
degradation of amorphous phase over crystalline phase in the initial stages of the degradation. 相似文献
19.
Ingrid H. Franke-Whittle Alberto Confalonieri Heribert Insam Mirko Schlegelmilch Ina Körner 《Waste management (New York, N.Y.)》2014,34(3):632-641
Anaerobic digestion is a waste treatment method which is of increasing interest worldwide. At the end of the process, a digestate remains, which can gain added value by being composted. A study was conducted in order to investigate microbial community dynamics during the composting process of a mixture of anaerobic digestate (derived from the anaerobic digestion of municipal food waste), green wastes and a screened compost (green waste/kitchen waste compost), using the COMPOCHIP microarray. The composting process showed a typical temperature development, and the highest degradation rates occurred during the first 14 days of composting, as seen from the elevated CO2 content in the exhaust air. With an exception of elevated nitrite and nitrate levels in the day 34 samples, physical–chemical parameters for all compost samples collected during the 63 day process indicated typical composting conditions. The microbial communities changed over the 63 days of composting. According to principal component analysis of the COMPOCHIP microarray results, compost samples from the start of the experiment were found to cluster most closely with the digestate and screened compost samples. The green waste samples were found to group separately. All starting materials investigated were found to yield fewer and lower signals when compared to the samples collected during the composting experiment. 相似文献
20.
Erik Stenvall Sandra Tostar Antal Boldizar Mark R.StJ. Foreman Kenneth Möller 《Waste management (New York, N.Y.)》2013,33(4):915-922
The compositions of three WEEE plastic batches of different origin were investigated using infrared spectroscopy, and the metal content was determined with inductively coupled plasma. The composition analysis of the plastics was based mainly on 14 samples collected from a real waste stream, and showed that the major constituents were high impact polystyrene (42 wt%), acrylonitrile–butadiene–styrene copolymer (38 wt%) and polypropylene (10 wt%). Their respective standard deviations were 21.4%, 16.5% and 60.7%, indicating a considerable variation even within a single batch. The level of metal particle contamination was found to be low in all samples, whereas wood contamination and rubber contamination were found to be about 1 wt% each in most samples. In the metal content analysis, iron was detected at levels up to 700 ppm in the recyclable waste plastics fraction, which is of concern due to its potential to catalyse redox reactions during melt processing and thus accelerate the degradation of plastics during recycling. Toxic metals were found only at very low concentrations, with the exception of lead and cadmium which could be detected at 200 ppm and 70 ppm levels, respectively, but these values are below the current threshold limits of 1000 ppm and 100 ppm set by the Restriction of Hazardous Substances directive. 相似文献