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21.
Valto P Knuutinen J Alén R 《Environmental science and pollution research international》2009,16(3):287-294
Background, aim, and scope In papermaking, there is a continuous interest both to minimize fresh water consumption and to reduce discharges into the
environment. These general trends mean an increase in the amounts of detrimental substances, such as resin and fatty acids,
in papermaking process waters. Resin acids, in particular, are responsible for much of the toxicity typically present in paper
mill effluents and, for this reason, the routine and rapid monitoring of these compounds in various process streams is necessary.
This also means that there is a continuous need to develop straightforward offline and online techniques to clarify problems
occurring, for example, as a result of the introduction of more intensively closed systems of water circulation. In the present
study, we describe the use of a novel, online, sample enrichment technique followed by atmospheric pressure chemical ionization–mass
spectrometry (APCI-MS) suitable for monitoring the concentration levels of common resin and fatty acids in papermaking process
waters.
Materials and methods The representative process water samples were taken from the grinding zone of a thermomechanical pulping mill. The samples
were first preconcentrated in a precolumn C18, and the analytes were transferred online to MS. The high intensive [M–H]− ion was used for the identification of each analyte since, according to the present ionization method, no other fragmentation
was observed. Laboratory-scale, online measurements with an online sample feed were carried out by connecting a centrifugal
pump and a ceramic filter to the APCI-MS.
Results Quality parameters, such as repeatability, linearity, and limit of detection (LOD), were determined by using dehydroabietic
acid (DHAA) in order to evaluate the suitability of the method for the rapid screening of concentration levels. This method
provided satisfactory linearity and a good correlation between analyte concentration and peak area. The suitability of the
system for the continuous analysis of the same acids was evaluated in laboratory-scale, online experiments. In all cases,
the response to changes in the analyte concentration was linear, and the repeatability of the system was also satisfactory.
Discussion Only a few studies have been published on the analysis of resin and fatty acids with MS techniques. The present method was
applied to the monitoring of dehydroabietic, oleic, and stearic acids. The quality parameters were highly comparable with
those reported earlier, and the LOD values of the DHAA were below the levels usually encountered in process waters. The quality
parameters were only slightly higher than those obtained by the traditional methods of analysis, probably due to the absence
of an effective sample clean-up before analysis.
Conclusions The results of the laboratory-scale, online experiments indicated that the online enrichment APCI-MS system is a suitable
alternative for monitoring the concentration levels of selected resin and fatty acids in papermaking process waters. The method
can be used, for example, to provide useful information about the concentration levels of these acids in different stages
of the process, thus signaling possibly impending problems. In general, faster and simpler measurements are needed to meet
the requirements for a reduction in fresh water usage in papermaking.
Recommendations and perspectives Compared to the conventional methods used for this purpose, the main benefits of the method are rapidity of measurement, simplicity
of use, and absence of the need for multistage sample treatments (short analysis time). For this reason, this online method
is more suitable for the control of papermaking by analyzing the concentration levels of interfering substances (i.e., selected
resin and fatty acids) than an offline analysis detailing all the individual extractives-based compounds in process streams.
It is also obvious that the technique can easily be modified for other environmental pollutants as well. 相似文献
22.
Kiljunen M Vanhatalo M Mäntyniemi S Peltonen H Kuikka S Kiviranta H Parmanne R Tuomisto JT Vuorinen PJ Hallikainen A Verta M Pönni J Jones RI Karjalainen J 《Ambio》2007,36(2-3):257-264
This study examines the extent to which Finnish human dietary intake of organochlorines (PCDD/Fs and PCBs) originating from Northern Baltic herring can be influenced by fisheries management. This was investigated by estimation of human intake using versatile modeling tools (e.g., a herring population model and a bioenergetics model). We used a probabilistic approach to account for the variation in human intake of organochlorines originating from the variation among herring individuals. Our estimates were compared with present precautionary limits and recommendation for use. The results show that present consumption levels and frequencies of herring give a high probability of exceeding recommended intake limits of PCDD/Fs and PCBs. Furthermore, our results clearly demonstrate that in the risk management of dioxinlike organochlorines, regulating fishing (in this case increasing fishing pressure) is a far less effective way to decrease the risk than regulating the consumption of herring. Increased fishing would only slightly decrease organochlorine concentrations of herring in the Finnish fish market. 相似文献
23.
Raimo Lilja 《Journal of Cleaner Production》2009,17(9):863-872
The aim of this article is to analyse the challenges and opportunities in applying a sector specific negotiated agreement for promoting waste prevention and material efficiency in Finnish industry. The study was conducted mainly through structured interviews targeted at the main stakeholders. By using an existing agreement on energy efficiency as the initial model, a concept for a material efficiency agreement was developed in an iterative process by balancing the expectations and doubts expressed in the stakeholders' views.As a result, the proposed concept represents a platform of dialog between the relevant Ministries and industrial organisations for setting sector specific targets for material efficiency, waste recycling and waste prevention. The targets could also include some qualitative issues concerning material efficiency in the value chain and cover several actors in the life cycle of targeted industrial products. A vision of the interaction between the negotiated agreement and other policy instruments is presented. 相似文献
24.
Eija K. Saski Raimo Mikkola Jussi V. K. Kukkonen Mirja S. Salkinoja-Salonen 《Environmental science and pollution research international》1997,4(4):194-202
Environmental properties of organic matter contained halogen and sulfur were studied in sediments of bleached kraft pulp mill
effluent (BKME) recipient lakes and 2 m3 outdoor enclosures (mesocosms). The BKME contributed to 1% (v/v) of the total water flow in the lake downstream of the pulp
mill where the sediments contained 1.7 to 4 mg of tetrahydrofuran extractable organic halogen (EOX-Cl) and 0.6 to 0.8 mg of
tetrahydrofuran extractable organic sulfur (EOS-S) g−1 of organic matter. Upstream sediment contained 0.03 mg of EOXCl and 0.7 mg of EOS-S g−1 of organic matter. EOX was a better indicator for the influence of BKME in the recipient sediment than EOS. The polarity
of BKME contained EOX corresponded to log Kow of < 1, and that of the downstream sediment contained EOX to > 4.5. HP-SEC analysis of the molecular weight distribution
(MWD) of the EOX showed a peak between 300 to 600 g mol−1 for the BKME and between 1000 to 2000 g mol−1 for the downstream sediment. The MWD of the BKME contained EOS peaked at 300 to 1000 g mol−1, and that of the downstream sediment contained EOS at 1000 to 5000 g mol−1. These results indicate that BKME contained organic halogen and sulfur undergo major structural transformations when incorporated
into sediment. The biota-to-sediment accumulation factor (BSAF) of EOX from sediments formed downstream of the mill and in
the mesocosms to the lipids ofLumbriculus variegatus was 0.4 to 0.7. This is of a similar order of magnitude to the BSAF reported for 2,3,7,8-tetrachlorodibenzop-dioxin and 2,3,7,8-tetrachlorodibenzofuran. 相似文献
25.
Walker TR Habeck JO Karjalainen TP Virtanen T Solovieva N Jones V Kuhry P Ponomarev VI Mikkola K Nikula A Patova E Crittenden PD Young SD Ingold T 《Ambio》2006,35(5):220-228
Using interdisciplinary field research in the Usa Basin, northeast European Russia, we compared local inhabitants' perception of environmental problems with chemical and remote-sensing signatures of environmental pollution and their local impacts. Extensive coal mining since the 1930s around Inta and Vorkuta has left a legacy of pollution, detected by measuring snowpack, topsoil, and lichen chemistry, together with remote-sensing techniques and analysis of lake water and sediments. Vorkuta and its environs suffered the worst impacts, with significant metal loading and alkalization in lakes and topsoils, elevated metals and cations in terricolous (reindeer) lichens, and changes in vegetation communities. Although the coal industry has declined recently, the area boasts a booming oil and gas industry, based around Usinsk. Local perceptions and concerns of environmental pollution and protection were higher in Usinsk, as a result of increased awareness after a major oil spill in 1994, compared with Vorkuta's inhabitants, who perceived air pollution as the primary environmental threat. Our studies indicate that the principal sources of atmospheric emissions and local deposition within 25 to 40 km of Vorkuta were coal combustion from power and heating plants, coal mines, and a cement factory. Local people evaluated air pollution from direct observations and personal experiences, such as discoloration of snow and respiratory problems, whereas scientific knowledge played a minor role in shaping these perceptions. 相似文献
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