排序方式: 共有49条查询结果,搜索用时 15 毫秒
31.
K. Ootsuka N. Arashi Y. Hishinuma S. Matsuda F. Nakajima M. Mukai 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1053-1056
The body of information presented in this paper is directed to those individuals concerned with the catalytic NOx removal reactor for a dirty (containing dust) flue gas. In the case of treating a dirty flue gas, the concentration of dust is the most important factor. While the dirty gas passes through the catalytic reactor, dust particles deposit and plug up the catalyst causing the reactor pressure loss to rise. As a result, the NOx reduction efficiency decreases more and more, and continuous operation becomes impossible. A new type of NOx removal reactor for dirty flue gas, the intermittent moving bed reactor, has been developed. The following characteristics have been evaluated: (1) method of calculating reactor pressure loss caused by dust particles, (2) static pressure distribution across the catalyst bed in the reactor, (3) method of evaluating uniform movement of catalyst and (4) reentrainment pattern of dust by catalyst movement. After carrying out various successful pilot plant tests, the information needed for construction and operation of a commercial plant has been developed. 相似文献
32.
S. Matsuda M. Takeuchi T. Hishinuma F. Nakajima T. Narita Y. Watanabe 《Journal of the Air & Waste Management Association (1995)》2013,63(4):350-353
The body of Information presented in this paper is directed to those Individuals concerned with the removal of NOx in combustion flue gases. A catalytic process for the selective reduction of nitrogen oxides by ammonia has been investigated. Efforts were made toward the development of catalysts resistant to SOx poisoning. Nitrogen oxides were reduced over various metal oxide catalysts in the presence or absence of SOx(SO2 and SO3). Catalysts consisting of oxides of base metals (for example, Fe2O3) were easily poisoned by SO3, forming sulfates of the base metals. A series of catalysts which are not susceptible to the SOx poisoning has been developed. The catalysts possess a high activity and selectivity over a wide range of temperatures, 250—450°C. The catalysts were tested in a pilot plant which treated a flue gas containing 110-150 ppm NOx, 660-750 ppm SO2, and 40-90 ppm SO3. The pilot plant was operated at 350°C and at a space velocity of 10,000 h-1. The removal of nitrogen oxides was more than 90% for several months. A mechanism of the NO-NH3 reaction has also been investigated. It is found that NO reacts with NH3 at a 1:1 mole ratio in the presence of oxygen and the reaction is completely inhibited by the absence of oxygen. The experimental data show that the NO-NH3 reaction in the presence of oxygen is represented byNO + NH3 + 1/4 O2 = N2 + 3/2 H2O. 相似文献
33.
Tsuyoshi Noma Katsuki Ide Jun Yoshikawa Kazutaka Kojo Hiroshi Matsui Ryo Nakajima Kiyoshi Imai 《Journal of Material Cycles and Waste Management》2012,14(3):153-161
To achieve both high-efficiency power generation and high detoxification performance, advanced-type waste power generation plants such as pyrolysis and gas reforming plants are suggested. Further surveys on actual operational data of these plants are required in terms of reliability of the system when it is introduced to waste disposal sites. To verify the technical effectiveness of advanced-type waste power generation using the pyrolysis and gas reforming method, we evaluated 10?tons/day of municipal solid wastes (MSW) treated in a demonstration plant. A demonstration test was conducted over 100?days including 35?consecutive days of operation treating MSWs. The test results show high recycling performance and harmless nature of the plant which proves it to be an excellent waste recycling system. Major test results are as follows: (1) stabilization of waste treatment is possible with the wastes of various qualities, (2) clean gas is produced from the waste whose energy recovery ratio is approximately 40?%. (3) 99.3?% weight % of dried waste are recovered as valuable materials such as clean gas, char and metal, (4) total amount of dioxin emission to the outside of the plant is very small, down to 0.0051–0.018?μg?TEQ per ton waste. 相似文献
34.
Todaka T Hirakawa H Kajiwara J Hori T Tobiishi K Onozuka D Kato S Sasaki S Nakajima S Saijo Y Sata F Kishi R Iida T Furue M 《Chemosphere》2007,69(8):1228-1237
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho coplanar polychlorinated biphenyls (non-ortho PCBs), and mono-ortho coplanar polychlorinated biphenyls (mono-ortho PCBs) in blood collected between 2002 and 2004 from 195 pregnant women living in Sapporo City of Hokkaido Prefecture, Japan. The present study is one of the few studies in which PCDDs, PCDFs, and dioxin-like PCBs have been measured in the blood of pregnant women. Of the 195 pregnant women, 101 were primipara (mean: 28.8 years) and 94 were multipara (mean: 32.4 years). The arithmetic mean total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs of primiparous and multiparous mothers in Sapporo City were 17.4 (median: 15.7) and 14.0 (median: 13.9)pgTEQ/glipid, respectively, and the concentrations were in the range of 6.6-43.4 and 3.4-28.2pgTEQ/glipid, respectively. In regard to the relationship between the total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in maternal blood and the number of deliveries or age of primiparous and multiparius mothers, the levels of these dioxin-like compounds tended to decrease with increases in the number of deliveries and significantly increased with increasing maternal age in both groups. Furthermore, significant correlations were observed between the total TEQ concentrations of these dioxin-like compounds and the age of primiparae and multiparae. The total TEQ concentration of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs measured in 195 pregnant women has decreased compared to past levels in Japan for the last several decades. The results of the present study have indicated that dioxin contamination in the blood of young women in Japan is continuing to decrease. 相似文献
35.
Asako Nishijima Jun Nakatani Kazuo Yamamoto Fumiyuki Nakajima 《Journal of Material Cycles and Waste Management》2012,14(1):52-64
Many life cycle assessment studies have evaluated and compared the environmental performance of various technologies for recycling
plastic containers and packaging in Japan and other countries. However, no studies have evaluated the combination of recycling
technologies in consideration of the resin composition in terms of the quantity of each recycled product so as to maximize
their environmental potential. In this study, 27 scenarios of recycling schemes for household waste plastic containers and
packaging are developed through integrating a conventional recycling scheme with additional recycling schemes. The conventional
recycling scheme involves municipal curbside collection and either the material recycling or feedstock recycling of waste
plastics. The additional recycling schemes are feedstock recycling in steel works of the residue from conventional material
recycling processes, and corporate voluntary collection and independent material recycling of specific types of plastic trays.
Life cycle assessment based on the modeling of recycling processes considering the resin composition in terms of the quantity
of each recycled product is applied to evaluate and compare these scenarios from the viewpoints of fossil resource consumption
and CO2 emission. The results show that the environmental loads are reduced in all scenarios including the additional recycling schemes
compared with the conventional recycling scheme. However, the independent plastic tray recycling scheme exhibits lower additional
environmental savings when the residue recycling scheme is integrated with the conventional material recycling scheme. This
is because both additional recycling schemes aim to utilize polystyrene and polyethylene terephthalate, which would otherwise
be incinerated as residue from material recycling processes. The evaluation of the environmental loads of plastic recycling
with consideration of the resin composition in terms of the quantity of each recycled product makes it possible to investigate
recycling schemes that integrate different technologies to maximize their environmental potential. 相似文献
36.
Miyuki Nishiyama Akihiko Sekizawa Kohei Ogawa Hideaki Sawai Hiroaki Nakamura Osamu Samura Nobuhiro Suzumori Setsuko Nakayama Takahiro Yamada Masaki Ogawa Yukiko Katagiri Jun Murotsuki Yoko Okamoto Akira Namba Haruka Hamanoue Masanobu Ogawa Kiyonori Miura Shunichiro Izumi Yoshimasa Kamei Haruhiko Sago 《黑龙江环境通报》2016,36(12):1121-1126
37.
Results of surveys on Polychlorinated biphenyls (PCB) and organochlorine insecticides (HCH and DDT) in fish and shellfish from Lake Biwa were summarized from 1987 to 1996. In 1975, fish and shellfish in Lake Biwa were highly contaminated with PCB, HCH and DDT but recently in 1992–1996 the concentrations of these chemicals were very low and nearly constant. In the composition of HCH isomers, β‐HCH was dominant in all kinds of fish and shellfish. In the composition of DDT and DDT metabolites, pp'‐DDE was similarly dominant in all kinds of fish and shellfish. Further, the data in Lake Biwa were compared with those in Lake Michigan and Lake Baikal. 相似文献
38.
Christensen AM Nakajima F Baun A 《Environmental pollution (Barking, Essex : 1987)》2006,144(2):621-625
The urban stream Store Vejle? (Denmark), which receives discharges of urban runoff, was investigated using a combination of biological toxicity tests and chemical analysis. The urban stormwater and road runoff gave low, but statistically significant, effects on the reproduction of the alga Pseudokirchneriella subcapitata. In all pre-concentrated water samples toxic effects were found and differences in toxicity depending on time and location of sampling were identified. Undiluted pore water samples from sediments collected in the stream were all toxic towards the algae and dilutions from 4 to 14 times were needed compared to a pore water sample from an unpolluted stream where a dilution factor of only 1.6 was required. A qualitative correlation between the toxicity of the pore water and the degree of pollution as evidenced by the metal concentration was observed, but statistically significant correlations could not be established by ranking procedures of, e.g. metal content or PAH-concentrations versus the observed toxicity. 相似文献
39.
M Nakajima 《Journal of environmental science and health. Part. B》1983,18(1):147-172
The inhibitory potencies of BHC isomers against Na+-K+- ATPase, yeast growth and nerve conduction of the American cockroach were determined. The insecticidal and neuroexcitatory activities of a number of analogs with the same configuration as lindane in which some chlorine atoms had been replaced by other substituents were also examined against American cockroaches. The structure-activity relationships and the mode of action of lindane and its analogs were discussed. Their metabolic fate was studied extensively in vivo as well as in vitro. The critical step in the biodegradation of lindane is the cleavage of C-H bonds which we found by utilizing the isotope effect of hexadeuterated lindane. 相似文献
40.
Funasaka K Miyazaki T Kawaraya T Tsuruho K Mizuno T Nakajima H Yamamoto T Hara H 《Environmental pollution (Barking, Essex : 1987)》1999,106(1):47-53
Atmospheric particulates were monitored on a typical high concentration day in early winter in Osaka, Japan, using a compact and portable eye-safe laser radar system. The height of mixing layer was about 0.4 km at 8:00 and gradually increased to 0.8 km at 14:00. The development of the layer was in inverse proportion to the decrease of particulates near the ground surface. Analysis of particulates collected with high-volume air samplers showed that concentrations of elemental carbon (EC), lead and ammonium ion near the surface decreased significantly from morning to midday, while concentrations of sulfate, nitrate, sodium and calcium ions were almost constant. The results obtained in the preliminary study suggest that anthropogenic particulates such as EC and lead are on the rise with development of mixing layer from morning to midday. 相似文献