Application of Infrared Spectroscopy to Exhaust Gas Analysis

Abstract

The Mohave Valley region of southern Nevada/southwestern Arizona has experienced elevated particulate concentrations and is classified as a PM₁₀ nonattainment area. Anthropogenic aerosol sources in the area include the Mohave Power Project (MPP), a 1,580-MW coal-fired power plant; motor vehicles; construction activities; and paved and unpaved road dust and disturbed desert soil. Aerosols may also be transported long distances from other areas, such as the Los Angeles Basin. Based on the infrequency of plume contact at sites in the valley (as determined by SO₂ measurements), it was believed that the contribution of the MPP to primary PM₁₀ was minimal and that fugitive dust was the primary source of ambient particulate matter.

To evaluate the magnitude of source contributors, PM₁₀ measurements were made using a medium-volume sampler along with ancillary meteorological and air quality measurements in the Mohave Valley at Bullhead City, Arizona, for a period of longer than one year (September 1988 through mid-October 1989). The aerosol filter samples were analyzed for mass, elements, ions, and carbon. Source apportionment using the Chemical Mass Balance (CMB) receptor model was performed. On average, geological dust was the major contributor to PM10 (79.5%), followed by primary motor vehicle sources (16.7%), secondary ammonium sulfate (3.5%), secondary ammonium nitrate (0.1%), and primary coal-fired power plant emissions (0.1%).     

Spatial and temporal variability of atmospheric mercury concentrations emitted from a coal-fired power plant in Mexico

Atmospheric mercury in the environment as a result of the consumption of fossil fuels, such as coal used in electricity generation, has gained increased attention worldwide because of its toxicity, atmospheric persistence, and bioaccumulation. Determining or predicting the concentration of this pollutant in ambient air is essential for determining sensitive areas requiring health protection. This study investigated the spatiotemporal variability of gaseous elemental mercury (GEM) concentrations and its dry deposition surrounding the Presidente Plutarco Elías Calles (CETEPEC) coal-fired power plant, located on Mexico’s Pacific coast. The CALPUFF dispersion model was applied on the basis of the daily consumption of coal during 2013 for each generating unit in the power plant and considering the local scale. The established 300-ng/m³ annual average risk factor considered by the U.S. Department of Health and Human Services (U.S. DHHS) and Integrated Risk Information System (IRIS) must not be exceeded to meet satisfactory air quality levels. An area of 65 × 60 km was evaluated, and the results show that the risk level for mercury vapor was not exceeded because the annual average concentration was 2.8 ng/m³. Although the predicted risk level was not exceeded, continuous monitoring studies of GEM and of particulates in the atmosphere, soil, and water may be necessary to identify the concentration of this pollutant, specifically that resulting from coal-fired power plants operated in environmental areas of interest in Mexico. The dry mercury deposition was low in the study area; according to the CALPUFF model, the annual average was 1.40E?2 ng/m²/sec. These results represent a starting point for Mexico’s government to implement the Minamata Convention on Mercury, which Mexico signed in 2013.

Implications: The obtained concentrations of mercury from a bigger coal-fired plant in Mexico, through the application of the CALPUFF dispersion model by the mercury emissions, are below the level recommended according to the US Department of Health and Human Services and Integrated Risk Information System. These results provide evidence of important progress in the planning and installation to the future of monitoring mercury stations in the area of interest.     

Noise Control Legislation

The national Environmental Protection Agency is expected to issue its recommendations on noise legislation some time during the latter part of 1973. This agency will assume primary responsibility for enforcing noise limits on new products, such as vehicles, construction equipment, electrical equipment, etc. Primary responsibility for community noise control will remain with local governments. Local EPA’s, now involved in air and water pollution, will be given the additional responsibility to enforce anti-noise legislation.This legislation will cover noise emissions fromvehicles, industries, construction equipment, residential air conditioners, and power equipment, and the noises that pervade multifamily dwellings. Responsibility for controlling aircraft noise will be shared with the FAA.

The noise ratings used in this legislation must be capable of easy measurement and yet correlate well with subjective response. For most noises the decibel level read on the A-scale of a sound level meter (dBA) is adequate. For aircraft noise a more complex rating scale must be used which includes consideration of the duration of the noise and the presence of a pure tone (engine whine). For still other noises (industries, construction) some consideration must be given to the total daily exposure time of the noise, along with its dBA rating.

New community noise ordinances will draw on the research and experience associated with the present Chicago, III., ordinance. Some modifications of this ordinance are expected, however, to improve enforcement procedures and to lower vehicle noise levels, which are considered the worst of all the community noise pollutants.     

Analysis of Industrial Boiler Solid Waste Impacts

This paper presents an examination of industrial coal-fired boiler waste products. Presently the atmospheric emissions from all new boilers larger than 250 × 10⁶ Btu/hr are controlled by existing New Source Performance Standards, and boilers smaller than 250 × 10⁶ Btu/hr are controlled to levels required by the regulations of the particular state in which the facility is located. The 1977 Clean Air Act Amendments, however, specify categories of sources for which EPA must develop revised New Source Performance Standards. Industrial coal-fired boilers are included as one of these categories, and a relevant issue concerns the potential amount of solid waste generated as a result of tightened emission standards that require flue gas desulfurization. This paper examines the air quality and solid waste impacts of moderate and stringent emission controls for particulate and SO₂ emissions from industrial coal-fired boilers.

Comparisons are presented of physical and chemical characterizations of the emissions and solid wastes produced when boilers are equipped with particulate and SO₂ control equipment. The SO₂ systems examined are lime spray drying, lime/limestone, double alkali, sodium throwaway, physically cleaned coal, and fluidized-bed combustion. The solid waste disposal alternatives and the disposal costs are discussed. The most common disposal methods used are landfill for dry wastes and impoundment for sludges, with special wastewater treatment requirements for the sodium throwaway aqueous wastes.     

The Plume Volume Molar Ratio Method for Determining NO2/NOx Ratios in Modeling—Part I: Methodology

ABSTRACT

During New Source Review modeling of proposed major sources of oxides of nitrogen (NO_x), maximum impacts are often predicted to occur very close to the source. At the same time, current modeling guidance recommends techniques that may be overly conservative in estimating the fraction of nitrogen dioxide (NO₂) in these plumes. A new technique called the Plume Volume Molar Ratio Method (PVMRM) is being proposed that simulates both chemistry and dispersion to better estimate the fraction of NO₂. This paper documents the methodology behind the technique. A follow-up pa-per¹ will evaluate its performance against a number of databases. This method is designed to realistically predict NO₂ fraction at close-in receptors yet still provide conservative estimates so that the air quality standards can be protected.     

Short Term Air Quality Standards for Suspended Particulate Matter in New York State

The Clean Air Act of 1970 requires each state to submit plans for implementation, maintenance, and enforcement of national ambient air quality standards subsequent to promulgation. Such plans have been geared to meet annual averages and maximum values. Based on experience in implementing the abatement plan it was found that air quality standards for averaging times shorter than one year are needed to shorten the time required to show contravention and to provide a basis for early corrective measures to regulate specific sources. This paper reports on the need and procedures used by New York State to develop such standards for suspended particulates. Daily suspended particulate data were analyzed by the Kolmogorov-Smirnov method goodness of fit technique to determine that the form of the distribution was log normal. A method developed by Larsen for predicting short term maximum concentrations for log normally distributed data was used to determine numerical values for one, two, and three month standards. Monthly, bi-monthly, and tri-monthly suspended particulate standards of 130, 110, and 100 µg/m³, respectively are proposed for the most extensively developed areas of New York State and correspondingly lower values for other areas. The methods used in this development are generally applicable to other air contaminants.     

Central power generation versus distributed generation – An air quality assessment in the South Coast Air Basin of California

This study assesses the air quality impacts of central power generation and compares them with the impacts of distributed generation (DG). The central power plant emissions factors used are from a newly installed combined cycle gas turbine system. Because location of power plants is a key parameter affecting air quality impacts, this study considers three potential locations for the installation of central power plants. Air quality impacts are evaluated for the South Coast Air Basin of California, in the year 2010, using a three-dimensional air quality model. Results are compared to air quality impacts from two potential DG scenarios to meet the same power demand as that of the central power plant case.Even though emissions from central generation are lower than emissions from the DG technology mix considered herein, central generation concentrates emissions in a small area, whereas DG spreads emissions throughout a larger cross-section of the air basin. As a result, air quality impacts from central generation are more significant than those from DG. The study also shows that assessment of air quality impacts from distributed and central generation should not only consider emissions levels, but also the spatial and temporal distribution of emissions and the air quality that results from atmospheric chemistry and transport – highly non-linear processes.Finally, analysis of population exposure to ozone and PM_2.5 shows that central generation located in coastal areas upwind from populated areas would cause the highest population exposure and even though emissions from central generation are considerably lower than DG emissions spread throughout the basin, results show that central generation causes a higher pollutant exposure than DG.     

An Evaluation of CO2, Measurements as an Indicator of Air Pollution

Measurements of ambient carbon dioxide (CO₂), made at the Continuous Air Monitoring Program station in downtown Cincinnati, Ohio, and at a rural location near Cincinnati are presented and evaluated to determine the significance of CO₂ data in urban air quality monitoring programs. Through analysis of rural CO₂ data and evaluation of combustion-sources by means of a diffusion model, it is demonstrated that the variation of urban CO₂ concentrations around the prevailing atmosphere background level results from combustion-and noncombustion {natural) sources. The concentration from natural sources can be substantial and in fact override the combustion sources. Because it is not yet practical to predict the contribution of natural sources to urban CO₂ concentrations, data obtained for-this gas have only limited utility as an index of air quality. Significant statistical relationships between CO₂ data and air quality measurements for summer months are shown to result from similar meteorological effects rather than similar sources. A seasonal and spatial variation of ih-ese relationships is postulated and subsequently demonstrated by analysis of CO₂ and air quality measurements from New Orleans, Louisiana, and SU Louis, Missouri.     

Air Pollution Assessments Of New Fossil Energy Technologies

This paper presents an overview on air pollution assessments of new fossil energy technologies for baseload electric generating plants. The discussion is oriented towards those who must understand the broad issues affecting the design and performance of such power plants. It is motivated by the potential air pollution problems caused by the near doubling of coal use projected for the next 15 years.

The paper first reviews the applicable emissions performance standards for these plants, as well as predictions of likely future standards needed to protect the environment. The conclusion is reached that significantly tighter emissions standards will apply in the future.

Next, the cost, emissions performance, and development status of the three major technology groups for coal fired baseload plants are reviewed. It is observed that while all of the technologies can meet the current standards, only the Baseline plant with Advanced Control Technology can meet future standards, without unreasonable increases in electrical generation costs. Furthermore, since Advanced Direct Combustion Technologies and Fuel Conversion Technologies are in very early stages of development, only the Baseline plant with Advanced Control Technology will be available to the utilities in the near term. This is because it will be evolved from the current commercial Baseline Technology.

Hence, it is concluded that the utilities will use mainly the Baseline coal fired plant with Advanced Control Technology to protect the environment for the next 15-20 years.     

Reduction of atmospheric emissions due to switching from fuel oil to natural gas at a power plant in a critical area in Central Mexico

ABSTRACT

A case study was conducted to evaluate the SO₂ emission reduction in a power plant in Central Mexico, as a result of the shifting of fuel oil to natural gas. Emissions of criteria pollutants, greenhouse gases, organic and inorganic toxics were estimated based on a 2010 report of hourly fuel oil consumption at the “Francisco Pérez Ríos” power plant in Tula, Mexico. For SO₂, the dispersion of these emissions was assessed with the CALPUFF dispersion model. Emissions reductions of > 99% for SO₂, PM and Pb, as well as reductions >50% for organic and inorganic toxics were observed when simulating the use of natural gas. Maximum annual (993 µg/m³) and monthly average SO₂ concentrations were simulated during the cold-dry period (152–1063 µg/m³), and warm-dry period (239–432 µg/m³). Dispersion model results and those from Mexico City’s air quality forecasting system showed that SO₂ emissions from the power plant affect the north of Mexico City in the cold-dry period. The evaluation of model estimates with 24 hr SO₂ measured concentrations at Tepeji del Rio suggests that the combination of observations and dispersion models are useful in assessing the reduction of SO₂ emissions due to shifting in fuels. Being SO₂ a major precursor of acid rain, high transported sulfate concentrations are of concern and low pH values have been reported in the south of Mexico City, indicating that secondary SO₂ products emitted in the power plant can be transported to Mexico City under specific atmospheric conditions.

Implications: Although the surroundings of a power plant located north of Mexico City receives most of the direct SO₂ impact from fuel oil emissions, the plume is dispersed and advected to the Mexico City metropolitan area, where its secondary products may cause acid rain. The use of cleaner fuels may assure significant SO₂ reductions in the plant emissions and consequent acid rain presence in nearby populated cities and should be compulsory in critical areas to comply with annual emission limits and health standards.     

Air Quality Impact of the Coal-Fired Power Plants in the Northern Passageway of the China West-East Power Transmission Project

Abstract

This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO₂) and coarse particulate matter (PM₁₀) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO₂ and PM₁₀ concentrations exceed 2 and 2.5 µg/m3, respectively. The maximum increases of the annually averaged SO₂ and PM₁₀ concentrations are 8.3 and 7.2 µg/m³, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO₂ and PM₁₀ concentrations fall to 4.9 and 4 µg/m³, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO₂ and PM₁₀ concentrations are, respectively, 6.3 and 5.6 µg/m³, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 µg/m³ after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.     

ESP Performance with Atmospheric Fluidized-Bed Combustion

Electric utilities considering atmospheric fluidized-bed combustion (AFBC) as an economic way to reduce SO₂ and NO_x emissions at coal-fired power plants must evaluate the impact AFBC will have on existing or planned plant systems and components. Because fly ash in AFBC units can have characteristics significantly different from that generated in pulverized-coal-fired boilers, a particular concern in this regard is the performance of the plant's particulate control equipment.     

Reduced mercury deposition in New Hampshire from 1996 to 2002 due to changes in local sources

Changes in deposition of gaseous divalent mercury (Hg(II)) and particulate mercury (Hg(p)) in New Hampshire due to changes in local sources from 1996 to 2002 were assessed using the Industrial Source Complex Short Term (ISCST3) model (regional and global sources and Hg atmospheric reactions were not considered). Mercury (Hg) emissions in New Hampshire and adjacent areas decreased significantly (from 1540 to 880 kg yr⁻¹) during this period, and the average annual modeled deposition of total Hg also declined from 17 to 7.0 μg m⁻² yr⁻¹ for the same period. In 2002, the maximum amount of Hg deposition was modeled to be in southern New Hampshire, while for 1996 the maximum deposition occurred farther north and east. The ISCST3 was also used to evaluate two future scenarios. The average percent difference in deposition across all cells was 5% for the 50% reduction scenario and 9% for the 90% reduction scenario.     

Emissions and risks associated with oxyfuel combustion: State of the science and critical data gaps

Oxyfuel combustion is a promising technology that may greatly facilitate carbon capture and sequestration by increasing the relative CO₂ content of the combustion emission stream. However, the potential effect of enhanced oxygen combustion conditions on emissions of criteria and hazardous air pollutants (e.g., acid gases, particulates, metals and organics) is not well studied. It is possible that combustion under oxyfuel conditions could produce emissions posing different risks than those currently being managed by the power industry (e.g., by changing the valence state of metals). The data available for addressing these concerns are quite limited and are typically derived from laboratory-scale or pilot-scale tests. A review of the available data does suggest that oxyfuel combustion may decrease the air emissions of some pollutants (e.g., SO₂, NOx, particulates) whereas data for other pollutants are too limited to draw any conclusions. The oxy-combustion systems that have been proposed to date do not have a conventional “stack” and combustion flue gas is treated in such a way that solid or liquid waste streams are the major outputs. Use of this technology will therefore shift emissions from air to solid or liquid waste streams, but the risk management implications of this potential change have yet to be assessed. Truly useful studies of the potential effects of oxyfuel combustion on power plant emissions will require construction of integrated systems containing a combustion system coupled to a CO₂ processing unit. Sampling and analysis to assess potential emission effects should be an essential part of integrated system tests.

Implications: Oxyfuel combustion may facilitate carbon capture and sequestration by increasing the relative CO₂ content of the combustion emission stream. However, the potential effect of enhanced oxygen combustion conditions on emissions of criteria and hazardous air pollutants has not been well studied. Combustion under oxyfuel conditions could produce emissions posing different risks than those currently being managed by the power industry. Therefore, before moving further with oxyfuel combustion as a new technology, it is appropriate to summarize the current understanding of potential emissions risk and to identify data gaps as priorities for future research.     

"Fuel Cleaning" and Materials Separation at Waste-to-Energy Plants

Separation of materials from municipal waste streams is not recycling. Successful recycling is demand-pulled rather than supply-driven; it depends on local markets that reuse separated materials. For this reason EPA's Office of Solid Waste has opposed national mandates for materials separation which do not address associated markets. But a recent Air Act decision could reverse that stance, potentially mandating high levels of materials separation for every new waste-to-energy (WTE) facility.

The decision holds that Best Available Control Technology (BACT) requires PSD permit applicants to consider separating "feasible" levels, of each "readily-ascertainable" waste component that contributes to air emissions when incinerated, despite their installation of advanced emissions controls or the lack of any evidence that emission concentrations would be further reduced by such "fuel cleaning." Because total emissions of any facility may always be reduced by requiring it to consume less fuel—or burn gas rather than oil, or use conservation rather than combust at all—the decision could radicalize New Source Review, transforming preconstruction permits from a process meant to assure specific emissions controls to one in which air agencies deny the existence of emitting sources. The decision could also delay preconstruction permits; force downsizing of disposal facilities EPA concedes to be necessary; accelerate landfill closures; inject air permit writers into solid waste management determinations; and make local waste infrastructure more difficult to finance. It demonstrates the slippery slopes created by attempts to convert single-medium statutes into multi-media programs under the banner of "pollution prevention."     

NO2 and SO2dispersion modeling and relative roles of emission sources over Map Ta Phut industrial area,Thailand

Map Ta Phut industrial area (MA) is the largest industrial complex in Thailand. There has been concern about many air pollutants over this area. Air quality management for the area is known to be difficult, due to lack of understanding of how emissions from different sources or sectors (e.g., industrial, power plant, transportation, and residential) contribute to air quality degradation in the area. In this study, a dispersion study of NO₂ and SO₂ was conducted using the AERMOD model. The area-specific emission inventories of NO_x and SO₂ were prepared, including both stack and nonstack sources, and divided into 11 emission groups. Annual simulations were performed for the year 2006. Modeled concentrations were evaluated with observations. Underestimation of both pollutants was found, and stack emission estimates were scaled to improve the modeled results before quantifying relative roles of individual emission groups to ambient concentration over four selected impacted areas (two are residential and the others are highly industrialized). Two concentration measures (i.e., annual average area-wide concentration or AC, and area-wide robust highest concentration or AR) were used to aggregately represent mean and high-end concentrations for each individual area, respectively. For AC-NO₂, on-road mobile emissions were found to be the largest contributor in the two residential areas (36–38% of total AC-NO₂), while petrochemical-industry emissions play the most important role in the two industrialized areas (34–51%). For AR-NO₂, biomass burning has the most influence in all impacted areas (>90%) except for one residential area where on-road mobile is the largest (75%). For AC-SO₂, the petrochemical industry contributes most in all impacted areas (38–56%). For AR-SO₂, the results vary. Since the petrochemical industry was often identified as the major contributor despite not being the largest emitter, air quality workers should pay special attention to this emission group when managing air quality for the MA.

Implications: Effective air quality management in Map Ta Phut Industrial Area, Thailand requires better understanding of how emissions from various sources contribute to the degradation of ambient air quality. Based on the dispersion study here, petrochemical industry was generally identified as the major contributor to ambient NO₂ and SO₂. By accounting for all stack and non-stack sources, on-road mobile emissions were found to be important in some particular areas.     

The distribution and sea–air transfer of volatile mercury in waste post-desulfurization seawater discharged from a coal-fired power plant

The waste seawater discharged in coastal areas from coal-fired power plants equipped with a seawater desulfurization system might carry pollutants such as mercury from the flue gas into the adjacent seas. However, only very limited impact studies have been carried out. Taking a typical plant in Xiamen as an example, the present study targeted the distribution and sea–air transfer flux of volatile mercury in seawater, in order to trace the fate of the discharged mercury other than into the sediments. Samples from 28 sampling sites were collected in the sea area around two discharge outlets of the plant, daily and seasonally. Total mercury, dissolved gaseous mercury and dissolved total mercury in the seawater, as well as gaseous elemental mercury above the sea surface, were investigated. Mean concentrations of dissolved gaseous mercury and gaseous elemental mercury in the area were 183 and 4.48 ng m^?3 in summer and 116 and 3.92 ng m^?3 in winter, which were significantly higher than those at a reference site. Based on the flux calculation, the transfer of volatile mercury was from the sea surface into the atmosphere, and more than 4.4 kg mercury, accounting for at least 2.2 % of the total discharge amount of the coal-fired power plant in the sampling area (1 km²), was emitted to the air annually. This study strongly suggested that besides being deposited into the sediment and diluted with seawater, emission into the atmosphere was an important fate for the mercury from the waste seawater from coal-fired power plants.     

An Air Pollution Modeling Study Using Three Surface Coverings Near the New International Airport of Mexico City

Abstract

The dry lakebed of what once was the lake of Texcoco is the location selected for the New International Airport of Mexico City. This project will generate an important urban development near the airport with regional implications on air quality. Using a prognostic air quality model, the consequences of photochemical air pollution in the metropolitan area of Mexico City resulting from three possible coverings for the areas of the lakebed that are not occupied by the runway and terminal building are investigated. These coverings are desert, grassland, and water and occupy an area of 63 km². This study is based on a representative high pollution episode. In addition to reducing the emission of primary natural particles, the water covering generates a land-water breeze capable of maintaining enough ventilation to reduce pollutant concentrations over a localized region of the metropolitan area and may enhance the wind speed on the coasts of the proposed lake.     

Long-term monitoring and modeling of polychlorinated dibenzo-p-dioxins and dibenzofurans from municipal solid waste incinerators and surrounding area in northern Taiwan

Municipal solid waste incinerators (MSWIs) have long been the major contributors of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) to ambient air in Taiwan. After stringent MSWI emission standards were introduced in 2001, the long-term continuous monitoring of flue gas and ambient air quality became necessary to ensure the effectiveness of the related control strategies. Three MSWIs and the surrounding ambient air were investigated in the current study for PCDD/F characteristics during 2006 to 2011. The average concentrations in the flue gas ranged from 0.008?~?0.0488 ng I-TEQ/Nm³, which is much less than the emission standard in Taiwan (0.1 ng I-TEQ/Nm³) (I-TEQ is the abbreviation of International Toxic Equivalent). This led to extremely low levels in the ambient air, 0.0255 pg I-TEQ/Nm³, much less than the levels seen in most urban areas around the world. Additionally, the results obtained using the Industrial Source Complex Short-Term Dispersion Model (ISCST3) indicate that the PCDD/F contributions from the three MSWIs to the ambient air were only in the range from 0.164?~?0.723 %. Principal component analysis (PCA) showed that the PCDD/Fs in the air samples had very similar characteristics to those from mobile sources. The results thus show that stringent regulations have been an effective control strategy, especially for urban areas, such as Taipei City.     

Reducing Emissions from Refuse Disposal

Estimates indicate that approximately 2.6% of the total atmospheric pollution in this country may originate as a result of refuse disposal. Although this may appear to be a comparatively low figure, it is important to note that refuse disposal is a universal problem: wherever we go, be the area urban, or rural, waste must be disposed of and in most cases the methods of disposal produce air pollution. Tabulated data indicates that the per capita rate of production has been increasing annually. In the city of Hartford, the quantity of refuse that is being burned in the municipal incinerator has been increasing at a rate of 5%/year. A comparison of the air pollutants emitted from open burning at a refuse disposal area, backyard burning and incineration of refuse in a municipal multiple chamber incinerator indicates that the quantity of pollutants emitted from the latter source is much less than those emitted from the other sources. The effect of having legislation with, enforcement authority and a program for regular inspections, has resulted in marked improvements of refuse disposal operations in Connecticut since June, 1966. Most of the burning still being done at refuse disposal areas is limited to only brush and demolition material. A multi-purpose incinerator is presently under construction in the city of Stamford, Conn. It is planned to demonstrate that not only bulky wastes and auto bodies, but also liquid wastes can be burned in the same unit without creating any adverse effect on the environment. This incinerator will be provided with an electrostatic precipitator for removing particulate emissions.

New methods of refuse disposal which are being tried are briefly described in this paper. All these methods tend to reduce or eliminate air pollution along with eliminating the health hazards normally related with open face dump type of operations.

The continual technological progress and improvements in methods of manufacture, packaging, and marketing of consumer products along with the economic, population, and industrial growth of the nation has resulted in an ever-mounting increase and change in the characteristics of the mass of material being discarded by the purchaser. In May 1967, a Three-State Conference on Air Resource Management was held at the City College of the City University of New York. This conference consisted of a number of panels or committees which discussed specialized areas of the problem of air pollution and its control. A portion of the introductory remarks from the panel report of the Solid Waste Committee1 is as follows: