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1.
Baseline study of methane emission from open digesting tanks of palm oil mill effluent treatment 总被引:1,自引:0,他引:1
Anthropogenic release of greenhouse gases, especially CO2 and CH4 has been recognized as one of the main causes of global warming. Several measures under the Kyoto Protocol 1997 have been drawn up to reduce the greenhouse gases emission. One of the measures is Clean Development Mechanisms (CDM) that was created to enable developed countries to cooperate with developing countries in emission reduction activities. In Malaysia, palm oil industry particularly from palm oil mill effluent (POME) anaerobic treatment has been identified as an important source of CH4. However, there is no study to quantify the actual CH4 emission from the commercial scale wastewater treatment facility. Hence, this paper shall address the CH4 emission from the open digesting tanks in Felda Serting Hilir Palm Oil Mill. CH4 emission pattern was recorded for 52 weeks from 3600 m3 open digesting tanks. The findings indicated that the CH4 content was between 13.5% and 49.0% which was lower than the value of 65% reported earlier. The biogas flow rate ranged between 0.8 l min−1 m−2 and 9.8 l min−1 m−2. Total CH4 emission per open digesting tank was 518.9 kg day−1. Relationships between CH4 emission and total carbon removal and POME discharged were also discussed. Fluctuation of biogas production was observed throughout the studies as a result of seasonal oil palm cropping, mill activities, variation of POME quality and quantity discharged from the mill. Thus only through long-term field measurement CH4 emission can be accurately estimated. 相似文献
2.
In this study we investigated both the decomposition and unintentional formation of polychlorinated biphenyl congeners during combustion experiments of refuse-derived fuel (RDF) and automobile shredder residue (ASR) at several stages in thermal treatment plant equipment composed of a primary combustion chamber, a secondary combustion chamber, and other equipments for flue gas treatment. In both experiments, the unintentional formation of PCB occurred in the primary combustion chamber at the same time as the decomposition of PCB in input samples. By combusting RDF, non-ortho-PCB predominantly formed, whereas ortho-PCB and symmetric chlorinated biphenyls (e.g., #52/69, #87/108, and #151) tended to be decomposed. ASR formed the higher chlorinated biphenyls more than RDF. These by-products from ASR had no structural relation with ortho-chlorine. Lower chlorinated biphenyls appeared as predominant homologues at the final exit site, while all congeners from lower to higher chlorinated PCB were unintentionally formed as by-products in the primary combustion chamber. This result showed that the flue gas treatment equipments effectively removed higher chlorinated PCB. Input marker congeners of RDF were #11, #39, and #68, while those for ASR were #11, #101, #110/120, and #118. Otherwise, combustion marker congeners of RDF were #13/12, #35, #77, and #126, while those for ASR were #170, #194, #206, and #209. While the concentration of PCB increased significantly in the primary combustion chamber, the value of toxicity equivalency quantity for dioxin-like PCB decreased in the secondary combustion chamber and the flue gas treatment equipments. 相似文献
3.
Hasegawa J Guruge KS Seike N Shirai Y Yamata T Nakamura M Handa H Yamanaka N Miyazaki S 《Chemosphere》2007,69(8):1188-1194
The present research was intended to determine the suitability of the CALUX assay as a screening method for dioxins in fish oil used as a feed ingredient in Japan. Alteration of TEQ in fish oil according to newly proposed toxic equivalency factors (TEF) is also discussed. In the analysis, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in 41 fish oil samples were determined by using high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS) and CALUX bioassay. The mean TEQ values derived from 1998 WHO-TEF of PCDD/Fs and DL-PCBs were 2.6 and 9.9 pg g(-1) (ww), respectively. The levels of TEQ derived from the recently re-evaluated 2005 WHO-TEF were slightly lower than those of the former in both groups. Notably, the contribution of mono-ortho DL-PCBs to total 2005 WHO-TEQ was considerably decreased compared to the case of 1998 WHO-TEQ, resulting from the reduction in its TEF values, while the non-ortho DL-PCBs contribution was increased. The mean TEQ determined by CALUX assay for PCDD/Fs was approximately three times higher, whereas DL-PCBs was approximately two times lower than WHO-TEQ determined by HRGC/HRMS; the sum of PCDD/Fs and DL-PCBs was very similar by both methods. The correlation coefficients of TEQ between the CALUX assay and HRGC/HRMS analysis were 0.84, 0.89, and 0.90 for PCDD/Fs, DL-PCBs, and the sum, respectively. These results suggest that the CALUX assay is a very useful method for the screening of dioxin-related compounds in fish oils. 相似文献
4.
5.
Yuri Sekimoto Tomoki Okiharu Haruka Nakajima Toshihiro Fujii Koji Shirai Hiroshi Moriwaki 《Environmental science and pollution research international》2013,20(9):6531-6538
The aim of this study is to investigate the use of keratin colloidal solution, which was obtained from wool, for the removal of Pb(II) from water. The addition of keratin colloidal solution (15 g L?1, 0.30 mL) to a Pb(II) solution (1.0 mM, 0.90 mL, pH 5.0) resulted in the formation and precipitation of a Pb–keratin aggregate. Measurement of the Pb(II) and protein concentrations in the supernatant solution revealed that 88 and 99 % of the Pb(II) and keratin protein were removed from the solution, respectively. The maximum Pb(II) uptake capacity of keratin in the colloidal solution was 43.3 mg g?1. In addition, the Pb–keratin aggregate was easily decomposed via the addition of nitric acid, which enabled the recovery of Pb(II). However, aggregation did not occur in solutions with Pb(II) concentrations below 0.10 mM. Therefore, we used a keratin colloidal solution encapsulated in a dialysis cellulose tube to remove Pb(II) from 0.10 mM solutions, which enabled the removal of 95 % of the Pb(II). From these results, we conclude that keratin colloidal solution is useful for the treatment of water polluted with Pb(II). 相似文献
6.
In this study, we investigate association patterns of 249 bottlenose dolphin feeding groups off Sardinia Island (Italy) from
January 2000–May 2007 and describe how their association behaviour is related to their response to food patches created by
a marine fin fish farm. We also tested the hypothesis that dolphins have different social structures with different feeding
activities: Associations should decrease during opportunistic feeding behaviours as it is easier to capture prey, and cooperation
is not as necessary. Sixteen individually identified bottlenose dolphins were observed participating in both opportunistic
and not opportunistic feeding activities, with a mean of 30 ± 8 times and 9.6 ± 1 times, respectively. Bottlenose dolphins
show non-random social behaviour during feeding and this behaviour differs depending on their specific foraging activity.
Dolphin associations during feeding can be divided into three categories: acquaintances, affiliates, and feeding associates.
Association behaviour during fish farm feeding is consistent with our hypothesis that during opportunistic behaviours, benefits
from cooperation decrease, as it is easier to capture prey. Group size homogeneity in both feeding activities demonstrates
that the number of dolphins engaging in foraging is not necessarily related with cooperation levels. Moreover, an adult dolphin
may prefer to associate with a specific individual, independent of the sex, who shares the same foraging priorities. This
study is the first to show how aquaculture is not only directly affecting marine predators but could also indirectly affect
their social structure and behaviour. 相似文献
7.
In this study, a new method for calculating total PCB and toxic equivalents (TEQ) of coplanar PCB (Co-PCB) was proposed, called the 'PCB dual method'. This method analysed various kinds of technical PCB, samples contaminated by technical PCB and byproduct PCB. In the PCB dual method, a data set of 15 indicator congeners was utilized for the calculations, having IUPAC nos. #3, #8, #28, #52, #77, #101, #105, #118, #126, #138, #153, #180, #194, #206 and #209. The 15 congener set was chosen from the major congeners, determined by HRGC/HRMS analysis, in 18 technical PCB, Kanechlor, Aroclor, Clophen and Chlorofen, and 20 other samples, such as indoor air, flue gases, emission gases, municipal solid waste (MSW), ash and sealant. To obtain total PCB and TEQ of Co-PCB, the intermediate sum for the concentration of the 15 congeners was multiplied by each multiplication factor. As a result, we obtained the average factor used to calculate total PCB in technical PCB and other samples. For technical PCB, the factor was 3.01, while for indoor air samples, flue and emission gases, MSW, ash and sealants, the factors were 3.92, 4.16, 3.68, 4.52 and 4.77, respectively. Moreover, the factor used to calculate the TEQ of Co-PCB in Kanechlor and other source samples were also obtained. The factors for Kanechlor, indoor air samples and emission gases from a cement plant were in the order of 10(-5), while the factor for flue gases in a MSW incinerator was in the order of 10(-3). These data were valuable for the rough estimation of the TEQ of Co-PCB without separation from other PCB before individual measurements. 相似文献
8.
Shirai Yoshihito Wakisaka Minato Yacob Shahrakbah Ali Hassan Mohd Suzuki Shin’ichi 《Mitigation and Adaptation Strategies for Global Change》2003,8(3):237-252
Palm oil industry in Malaysia is one of the potential candidates for the CDM project because large amount of methane is emitted
from the lagoons and open digesting tank of the wastewater treatment system. Therefore the first objective of the project
is to investigate the actual GHG emission from the lagoons and open digesting tank in palm oil mills in order to establish
the baseline for CDM project. Results indicated that methane contribution to biogas released from the open digesting tank
and lagoon systems were 35% and 45%, respectively. These values are much lower than the reported value of 65% obtained by
complete anaerobic condition of lab-scale experiments. Based on actual methane release measurement and information gathered
from palm oil mill about wastewater treatment, significant amount of methane emission to the atmosphere can be reduced with
the installation of new closed digesting tank system converted from the open digesting tank such as just by covering it with
applying CDM. It is estimated that a total of RM2.6 million could be obtained from the selling of electricity generated from
biogas generation and Certified Emission Reduction(CER).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
Hongyu Huang Noriyuki Kobayashi Miwa Sakata Yuko Suzuki Fujio Watanabe Masanobu Hasatani Kiyoshi Matsuyama Shigenori Yoshida Yoshihito Mitsuhara 《Journal of Material Cycles and Waste Management》2007,9(2):182-187
Polychlorinated biphenyl (PCB) residues from the sodium dispersion (SD) process were employed as the raw materials for the
production of activated carbon using KOH activation. The pore properties, such as the specific surface area and pore size
distribution, were characterized using the Barrett–Joyner–Halenda method and the Horvath–Kawazoe method based on the N2 adsorption isotherm at 77 K. The activated carbon produced showed similar adsorption capacities and specific surface areas
to the commercially available product. The effects of the activation conditions on the porosity of the activated carbon produced
were studied. The most significant factor affecting the specific surface proved to be the activation temperature. The activated
carbon produced from PCB residues from the high-temperature (423–443 K) SD process had a binary pore size distribution well
developed in the 4 nm region and in the micropore region. The pore structure of the carbon produced from PCB residues from
the low-temperature (333–393 K) SD process had a wide range of micropores and mesopores. 相似文献
10.
Christine Susan Fagnant Liliana Margarita Sánchez-Gonzalez Nicolette A. Zhou Jill Christin Falman Michael Eisenstein Dylan Guelig Byron Ockerman Yifei Guan Alexandra Lynn Kossik Yarrow S. Linden Nicola Koren Beck Robyn Wilmouth Evans Komen Benlick Mwangi James Nyangao Jeffry H. Shirai Igor Novosselov Peter Borus David S. Boyle John Scott Meschke 《Food and environmental virology》2018,10(1):72-82
Environmental surveillance of poliovirus (PV) plays an important role in the global program for eradication of wild PV. The bag-mediated filtration system (BMFS) was first developed in 2014 and enhances PV surveillance when compared to the two-phase grab method currently recommended by the World Health Organization (WHO). In this study, the BMFS design was improved and tested for its usability in wastewater and wastewater-impacted surface waters in Nairobi, Kenya. Modifications made to the BMFS included the size, color, and shape of the collection bags, the filter housing used, and the device used to elute the samples from the filters. The modified BMFS concentrated 3–10 L down to 10 mL, which resulted in an effective volume assayed (900–3000 mL) that was 6–20 times greater than the effective volume assayed for samples processed by the WHO algorithm (150 mL). The system developed allows for sampling and in-field virus concentration, followed by transportation of the filter for further analysis with simpler logistics than the current methods. This may ultimately reduce the likelihood of false-negative samples by increasing the effective volume assayed compared to samples processed by the WHO algorithm, making the BMFS a valuable sampling system for wastewater and wastewater-impacted surface waters. 相似文献