A Global Outlook to the Carbon Dioxide Emissions in the World and Emission Factors of the Thermal Power Plants in Turkey

World primary energy demand increases with increases in population and economic development. Within the last 25 yr, the total energy consumption has almost doubled. For the purpose of meeting this demand, fossil energy sources are used and various pollutants are generated. CO₂ is also one of these gases, which cannot be removed like other pollutants, and it causes greenhouse effect and climate change. Reducing the CO₂ emission is very important because of the environmental concerns and regulations, especially the Kyoto Protocol. This paper reviews the estimated world carbon emissions, Turkey's situation in electrical energy production, emission amounts estimated until the year 2020 and emission factors for dust, SO₂, NO_x and CO₂. The estimated results show that CO₂ emissions from thermal power plants in Turkey will make about 0.66 % of the global CO₂ emissions in 2020.     

炉排炉焚烧垃圾过程中主要污染物的控制

概述了二恶英、重金属、酸性气体、灰渣等垃圾焚烧的主要污染物，以二段式（往复）焚烧炉为例，介绍了炉排炉焚烧处理工艺和污染控制设备。提出通过控制垃圾焚烧条件、尾气处理以及吸附等方法，可以有效控制二恶英类污染物的排放；重金属的控制可以用除尘器或使用相应的吸附剂处理；采用较为成熟的烟气处理技术，可以控制处理酸性气体；灰渣可采用固化稳定化或酸提取法处置。     

Modeling of Combined Aerosol and Photooxidant Processes in the Mediterranean Area

The combined UAM-AERO/RAMS modeling system has been applied to study the dynamics of photochemical gaseous species and particulate matter processes in the eastern Mediterranean area between the Greek mainland and the island of Crete. In particular, the modeling system is applied to simulate atmospheric conditions for two periods, i.e., 13-16 July 2000 and 26-30 July 2000. The spatial and temporal distributions of both gaseous and particulate matter pollutants have been extensively studied together with the identification of major emission sources in the area. New pre-processors were developed for the UAM-AERO model for evaluating detailed emission inventories for biogenic compounds, resuspended dust and sea salt. Comparison of the modeling results with measured data was performed and satisfactory agreement was found for a number of gaseous species. However, the model underestimates the PM₁₀ measured concentrations during summer. This is mainly due to the considerable underestimation of particulate matter emissions and in particular dust resuspension, the effect of forest fire emissions and the contribution of Saharan dust episodes.     

Characterization, leachability and valorization through combustion of residual chars from gasification of coals with pine

This paper presents the study of the combustion of char residues produced during co-gasification of coal with pine with the aim of characterizing them for their potential use for energy. These residues are generally rich in carbon with the presence of other elements, with particular concern for heavy metals and pollutant precursors, depending on the original fuel used.The evaluation of environmental toxicity of the char residues was performed through application of different leaching tests (EN12457-2, US EPA-1311 TCLP and EA NEN 7371:2004). The results showed that the residues present quite low toxicity for some of pollutants. However, depending on the fuel used, possible presence of other pollutants may bring environmental risks.The utilization of these char residues for energy was in this study evaluated, by burning them as a first step pre-treatment prior to landfilling. The thermo-gravimetric analysis and ash fusibility studies revealed an adequate thermochemical behavior, without presenting any major operational risks.Fluidized bed combustion was applied to char residues. Above 700 °C, very high carbon conversion ratios were obtained and it seemed that the thermal oxidation of char residues was easier than that of the coals. It was found that the char tendency for releasing SO₂ during its oxidation was lower than for the parent coal, while for NO_X emissions, the trend was observed to increase NO_X formation. However, for both pollutants the same control techniques might be applied during char combustion, as for coal. Furthermore, the leachability of ashes resulting from the combustion of char residues appeared to be lower than those produced from direct coal combustion.     

Long Term Trends in Concentration of Major Pollutants (SO<Subscript>2</Subscript>, CO,NO, NO<Subscript>2</Subscript>, O<Subscript>3</Subscript> and PM<Subscript>10</Subscript>) in Prague – Czech Republic (Analysis of Data Between 1992 and 2005)

To assess the effect of changes in traffic density and fuels used for heating at the beginning of the 1990s, 1992–2005 monthly averages of PM₁₀, SO₂, NO₂, NO, CO and O₃ from Prague, the Czech capital, were analyzed together with long term trends in emissions of major pollutants, fuel consumption and number of vehicles registered in Prague. The data from all monitoring stations were retrieved from the database of the state automated monitoring system. Correlation coefficients between ambient monthly averaged temperature and all pollutants of concern showed distinct seasonal trends. The results showed that while SO₂ and to some extent also CO concentrations dropped namely in the first half of the analyzed period (1992–1997) as a result decreased fossil fuel consumption for local heating, the behaviour of other pollutant concentrations followed a different pattern. PM₁₀ concentrations decreased during the beginning of the 1990s but showed a sign of increase after 2000. Concentrations of ozone and NO₂ did not reveal any significant change throughout the whole studied period. It can be concluded that during the studied period traditional urban sources of pollution, such as coal and oil combustion, lost their importance but were simultaneously substituted by pollutants from automotive transport (namely PM and NO₂) making the problem of air quality even worse.     

Tools for evaluation of impact associated with MSW incineration: LCA and integrated environmental monitoring system

The identification of significant pollutants emitted from the contamination source is the first step in evaluating the impact associated with anthropic activity. Municipal solid waste (MSW) incinerators are still generally perceived as great pollutant sources, in particular due to their gaseous emissions from the stack, which constitute the major effluent from the plant. In this work a life cycle assessment and an integrated environmental monitoring system were applied together, in order to obtain complete information about the incineration process and its environmental impact. The former is a proven methodology, but its application to waste management systems constitutes a relatively new field of application with a great developmental potential. The contribution of the incineration process to the different environmental impact categories was investigated, finding many avoided impacts due to energy recovery. The latter is an innovative approach that allows a remarkable understanding of impact due to a contamination source; interesting correlations were found between heavy metals both in gas emissions and in natural matrices in the surroundings.     

Incineration of healthcare wastes: management of atmospheric emissions through waste segregation

The amount of atmospheric pollutants emitted through the incineration of healthcare wastes can be estimated using emission factors. Emission factors have been published without including sufficient information about the types of wastes incinerated. This paper reports the first emission factors estimated for the incineration of wastes segregated into different types according to the Portuguese legislation. One controlled-air incinerator without air pollution control devices was used in the research. The main objectives of the study were: (i) to estimate the emission factors for particulate matter, dioxins, heavy metals and gaseous pollutants, according to the type of waste incinerated; (ii) to evaluate the quality of atmospheric emissions; and (iii) to define a methodology for the management of atmospheric emissions, evaluating the influence of type of waste incinerated and of the segregation method used on the emitted amounts. It was concluded that: (i) when emission factors are not associated with the type of incinerated mixture, the utility of the emission factors is highly doubtful; (ii) without appropriate equipment to control atmospheric pollution, incineration emissions exceed legal limits, neglecting the protection of human health (the legal limit for pollutant concentrations could only be met for NO(x), all other concentrations were higher than the maximum allowed: dioxins, 93-710 times; Hg, 1.3-226 times; CO, 11-24 times; SO(2), 2-5 times; and HCl, 9-200 times); (iii) rigorous segregation methodologies must be used to minimize atmospheric emissions, and incinerate only those wastes that should be incinerated according to the law. A rigorous segregation program can result in a reduction of the amount of waste that should be incinerated by 80%. A reduction in the quantity of waste incinerated results in a reduction on the amounts of pollutants emitted: particulate matter, 98%; dioxins, 99.5%; As, Cd, Cr, Mn and Ni, respectively, 90%, 92%, 84%, 77% and 92%; Hg and Pb, practically eliminated; SO(2) and NO(x), 93%; and CO and HCl, more than 99%.     

Ozone Episode in the Milan Metropolitan Area A Comparative Evaluation of UAM-V and CALGRID Models

Data from an ozone episode (2–5 June, 1998) in the Milan metropolitan area were used for an application of two photochemical grid models: UAM-V and CALGRID. To assure a fair comparison, the models were run on the same domain and grid size, with same source emission inputs, CALMET diagnostic meteorology, and initial and boundary conditions taken from air quality data and literature values. Hourly emissions were derived from the AutoOil-II programme inventory except for on-road mobile source emissions; a new traffic emission inventory, based on both COPERT II methodology and road classification has been developed. NO_x and O₃ concentration results were compared to local network monitoring data. Results indicate that both models predict the highest ozone values along the north-east direction and are able to reproduce the ozone daytime trend though differences can be found between the two models on ozone spatial distribution. Average normalised bias for both models is about 50%, peak daily ozone concentrations are underestimated, with simulated peak shapes broader than the observed ones and a temporal shift between the two models. Night-time concentration levels of pollutants were not successfully reproduced due to an incorrect parameterisation of vertical turbulence calling for further work.     

新型旋流除尘器在100万吨/年乙烯装置尾气除尘中的应用

为了去除石化行业乙烯装置裂解炉烧焦尾气中的颗粒污染物,对传统用于气体除尘的旋风分离器进行改进,设计了一种新型旋流除尘器,并将其应用于乙烯装置裂解炉清焦过程中。经新型旋流除尘器处理后,出口气中焦粉颗粒质量浓度基本控制在15 mg/m³以下,符合GB 31570—2016《石油炼制工业污染物排放标准》的排放要求（≤20 mg/m³）,平均分离效率达到92.8%,粒径在10 μm以上的焦粉颗粒得到大幅度去除。     

Dioxin emissions: Possible techniques for maintaining the limit of 0.1 ng TE m−3 (as of 1990/91)

Processes which will achieve up to 100-fold reduction of exhaust gas emissions of dioxin as proposed for the new German Standards are reviewed. A combination of processes which remove fly ash, NO_x, SO_x, HCl and other pollutants will also remove dioxins. Reduction of chlorinated compounds fed to the incinerator is not likely to make any significant difference. Good turbulence with elimination of cold spots in the firebox will ensure initial thermal destruction. Dioxins are synthesized on fly ash particles at temperatures between 200 and 400° C. Rapid temperature reduction across this range by water injection will greatly reduce dioxin levels. Catalytic inhibitors can also be used. Since dioxin is adsorbed on fly ash, efficient scrubbing is essential for high removal efficiency. Sorption on active carbon beds is also being evaluated.     

Urban Metal Flows – A Case Study of Stockholm. Review and Conclusions

Metals have rapidly accumulated in the anthroposphere, especiallyin urban areas, indicating possible environmental and resource problems. Here, Stockholm City was chosen for a case study of urban metal flows, i.e. metal inflow to, metals in the stock of,and metal outflow from the anthroposphere to the biosphere. Themetal stock of Stockholm is large and still growing. The large amounts of metals in the solid waste fraction totally dominatethe outflow from the city. For major parts of the stock, the emissions from goods in use are negligible. There are, however,goods applications corresponding to significant emissions: e.g. the traffic sector (Cu, Zn, Cr, Ni, Pb), the tapwater system (Cu), roofs/fronts or other metal surfaces (Cu, Zn). Today's known metal flows from the anthroposphere of Stockholm to the biosphere and sewage sludge are quantitatively dominated by Zn(34 ton y^-1) and Cu (14 ton y^-1). Historical and present emissions have resulted in high metal concentrations insediments (especially Cd, Hg and Pb, but also Cu and Zn), groundwater (Cu, Hg) and in soils (Hg, Cu, Pb). At present theannual median concentrations are below the Swedish limits for metals in sewage sludge, even if the safety margins aresmall for Cd, Hg and to some extent Cu. The flows of Cu and Zn to Stockholm soils are high with a significant accumulationindicating an environmental impact in a longer time perspective.High levels of metals in surface sediments in the waterenvironments reflects an ongoing input where these metals aretransported from known (Cu, Zn) and or partly unknown (Cd, Hg, Pb) sources. In future urban areas, monitoring of metal flows must be performed both in the anthroposphere and the biospherein order to have a pro active approach to urban environmentalproblems and to get prompt answers to measures taken.     

发电集团应对新火电厂大气污染物排放标准的思考

新的火电厂大气污染排放标准重点加大了对火电厂大气污染物中NOx的控制力度,收严了SO2、烟尘等污染物排放限值,增设了汞及其化合物控制指标。该标准的实施对发电企业的生存和发展带来一定的影响,为了落实新标准,发电集团应在法律法规政策及技术产业方面采取相应措施,加快除尘、脱硫、脱硝、脱汞等新技术的研究和应用,从单一污染物的总量控制向多污染物协同控制转变,积极探索和思考发电集团绿色低碳发展的道路。     

GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities

GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from ?290 kg CO₂ e (glass) to ?19 111 kg CO₂ e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO₂ e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard.     

Fluxes and Loading of Heavy Metals, Benzo[a]pyrene and Oil Products in Vilnius City

The concentrations of heavy metals Pb, Cd, Cu, Zn and Hg, benzo[a]pyrene and oil products (C₁₅–C₂₈) in bulk (wet and dry) atmospheric deposition in Vilnius city in 2005–2006 were analysed. The highest flux to the ground surface of the city residential area, reaching 1,680 mg m^?2 year^?1, was determined for oil products, which in atmospheric bulk deposition was estimated to be mainly in the form of solid sediments. Among heavy metals, the highest flux was determined for Zn (113.5 mg m^?2 year^?1), while the lowest flux was determined for Hg (0.06 mg m^?2 year^?1). The flux of investigated pollutants ranges from a few times, or for some pollutants, up to one order of magnitude higher at the urban sampling site in comparison to residential or background sites. Some hundred tons of oil products, approximately 52 tons of zinc and a considerably lower amount of mercury, benzo[a]pyrene and cadmium deposit yearly to the ground and water surface of Vilnius city. Metallic constructions related to transport and buildings, automobile exhausts, spills of fuel and lubricants are suggested to be the factors which result in the accumulation of high amounts of heavy metals, oil products and other pollutants on the ground surface of the city.     

Determining distribution coefficients for low cost adsorbents

As with other construction materials, coal fly ash contains trace metals that can leach into the natural environment. As part of a broader effort to encourage appropriate coal combustion product use in infrastructure applications (e.g., road construction, stabilization, and structural fill), this study evaluated traditional and low‐cost adsorbent alternatives for their capacity to attenuate trace metals. Batch sorption tests were used as a preliminary screen for a wide variety of low cost (e.g., steel byproducts, rubber dust, and compost) and innovative materials (e.g., kudzu, biofilm, and pond weed) as well as conventional materials (activated carbon, alumina, and zeolites). The removal rates were demonstrated in this study by observing the calculated distribution coefficient (K_d) which were determined using a program called MATLAB. Limestone and steel byproducts were found to be particularly effective with large K_d values of 15,740, 1,520, and 540 L kg^?1 for cadmium, chromium, and selenium and, for ladle refractory and mill scale, K_d values of 3,910, 670, and 1,760 L kg^?1 were observed. Among the three metals tested for this study, it was observed that most low cost and innovative materials removed cadmium quite efficiently; however, the removal of selenium and chromium depended on the substrate and prevailing pH. In general, these results suggest that alternative materials may have relevance in niche applications where leaching is a concern that can be addressed through enhanced attenuation capacity via blending or layering of adsorbents.     

The effect of dust emissions from open storage piles to particle ambient concentration and human exposure

The current study focus on the determination of dust emissions from piles in open storage yards of a municipal solid waste (MSW) composting site and the subsequent atmospheric dust dispersion. The ISC3-ST (Industrial Source Complex Version 3 – Short Term) model was used for the evaluation of the PM₁₀ ambient concentrations associated with the dispersion of MSW compost dust emissions in air. Dust emission rates were calculated using the United States Environmental Protection Agency proposed dust resuspension formulation from open storage piles using local meteorological data. The dispersion modelling results on the spatial distribution of PM₁₀ source depletion showed that the maximum concentrations were observed at a distance 25–75 m downwind of the piles in the prevailing wind direction. Sensitivity calculations were performed also to reveal the effect of the compost pile height, the friction velocity and the receptor height on the ambient PM₁₀ concentration. It was observed that PM₁₀ concentrations (downwind in the prevailing wind direction) increased with increasing the friction velocity, increasing the pile height (for distances greater than 125 m from the source) and decreasing the receptor height (for distances greater than 125 m from the source). Furthermore, the results of ISC3-ST were analysed with the ExDoM (Exposure Dose Model) human exposure model. The ExDoM is a model for calculating the human exposure and the deposition dose, clearance, and finally retention of aerosol particles in the human respiratory tract (RT). PM₁₀ concentration at the composting site was calculated as the sum of the concentration from compost pile dust resuspension and the background concentration. It was found that the exposure to PM₁₀ and deposited lung dose for an adult Caucasian male who is not working at the composting site is less by 20–74% and 29–84%, respectively, compared to those for a worker exposed to PM concentrations at the composting site.     

On-line detection of metal pollutant spikes in MSW incinerator flue gases prior to clean-up

SUWIC's unique mobile metals emissions monitoring laboratory has been used to measure metal pollutant spikes in the flue gas from a municipal solid waste incinerator, prior to gas clean-up. The laboratory has a heated sampling probe that extends into the plant, allowing the simultaneous on-line measurement of the concentrations of more than 30 metals by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). As little is known about temporal variation in metal concentrations, this capability is seen as a major advance. The graphs of continuous measurements show that the elemental loading is far from uniform, and that concentrations fluctuate far more than may have been conventionally expected. There are occasional significant spikes in the emission profiles for cadmium and mercury, which are believed to be due to specific items in the waste feed material. Continuous monitoring measurements are of significant value for those seeking to model metal behaviour in combustion and in pollution control devices.     

Progress toward remediation of the Sydney Tar Ponds: A major Canadian PCB/PAH “superfund” site

The Muggah Creek estuary in Sydney, Nova Scotia, received liquid and solid wastes from a steel mill and its associated coke ovens for approximately 100 years. This resulted in pollution of soils and sediments with polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), heavy metals, and other pollutants, including those in untreated domestic wastewaters. The Canadian federal and Nova Scotia provincial governments organized the Sydney Tar Ponds Agency (STPA) to develop a remediation approach for the Coke Ovens site soils and Sydney Tar Ponds sediments. The STPA developed a remediation approach for the Sydney Tar Ponds sediments, involving solidification/stabilization (S/S) through mixing cement and other materials into the sediments, and then capping them as a waste pile. High‐density polyethylene (HDPE) plastic sheeting vertical barriers are proposed to be used to divert groundwater and surface water from entering into the S/S‐treated sediments and to collect any water and associated pollutants released from the S/S‐treated sediments. The Coke Ovens site soils are proposed to be landfarmed to reduce some of the PAHs and other pollutants and then capped with a layer of soil. This remediation program is estimated to cost on the order of $400 million (CAN). This article presents a review of the significant potential problems with the STPA proposed remediation strategy of the Sydney Tar Ponds sediments and Coke Ovens site soils. © 2006 Wiley Periodicals, Inc.     

Effluents from MBT plants: Plasma techniques for the treatment of VOCs

Mechanical–biological treatments (MBTs) of urban waste are growing in popularity in many European countries. Recent studies pointed out that their contribution in terms of volatile organic compounds (VOCs) and other air pollutants is not negligible. Compared to classical removal technologies, non-thermal plasmas (NTP) showed better performances and low energy consumption when applied to treat lowly concentrated streams. Therefore, to study the feasibility of the application of NTP to MBTs, a Dielectric Barrier Discharge reactor was applied to treat a mixture of air and methyl ethyl ketone (MEK), to simulate emissions from MBTs. The removal efficiency of MEK was linearly dependent upon time, power and specific input energy. Only 2–4% of MEK was converted to carbon dioxide (CO₂), the remaining carbon being involved in the formation of byproducts (methyl nitrate and 2,3-butanedione, especially). For future development of pilot-scale reactors, acting on residence time, power, convective flow and catalysts will help finding a compromise between energy consumption, desired abatement and selectivity to CO₂.