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1.
The Air Quality Control Program of the Commonwealth of Massachusetts has developed an implementation plan for the Metropolitan Boston Intrastate Air Quality Control Region as required by PL 90-148. An essential part of the plan was a set of control regulations designed to achieve and maintain an air quality compatible with adopted standards. Control strategy modeling was used as a tool in selecting the most appropriate regulations to achieve this goal. The body of information presented in this paper is directed to those state and county air pollution control officials concerned with the formulation and evaluation of regulations.

The paper details the procedures developed and presents a case history of their use in the region. The system is a synthesis of generally-available software and newly-developed computer programs to provide ahighly automated computational structure. It permits rapid simulation of the emissions resulting from the application of various control regulations. Predictions on the changes expected in ambient air quality levels are then made by the use of the Air Quality Display Model (AQDM).

The initial step in the application was a calibration of the system using predicted and measured annual concentrations. This step yielded correlation coefficients of 0.92 for sulfur dioxide and 0.85 for particulates. Subsequently, the system was used to evaluate the baseline case of uncontrolled sulfur in fuel use. Alternative sulfur control strategies were tested for compatibility with air quality standards. The principal strategies tested were: (a) 1% sulfur uniformly throughout the region; (6) 1% sulfur in core area of region, 2.2% sulfur elsewhere; (c) 0.5% sulfur in core area of region, 2.2% sulfur elsewhere; (d) 0.5% sulfur in core area of region, 1.0% sulfur elsewhere.

Strategies (b) and (d) were implemented into a time phased set of control regulations for the region.

Experience with the system has shown it to be a convenient and rapid method for simulating the effects of control regulations. Furthermore, the utility of this initial model warrants expansion of its application to the other air quality control regions in the Commonwealth.  相似文献   

2.
Fumes from a FeSi (75% Si) open submerged-arc furnace have been carefully collected on filters and the particle size distributions determined by optical, and transmission electron microscope methods. The sampling method, counting technique, and some of the theory for computing the results are briefly described.  相似文献   

3.
This paper deals with packed beds in discussion of separation of entrained particles and fumes from an air stream. Packed beds develop between the gas and liquid a maximum of contact in order to get maximum mass transfer from a gas to a liquid phase, and they are considered to be one of the better methods of scrubbing contaminants from a gas stream.  相似文献   

4.

More knowledge on the composition of aqueous extracts of broiler litter amended for Water Soluble P (WSP) reduction would help to understand how amendments work. We measured pH, concentrations of Ca, Mg, Fe, Al, Cu, Mn, Zn, Molybdate Reactive P (MRP), and Dissolved Unreactive P (DUP) in water extracts of broiler litter treated with aluminum sulfate (ALS), ferrous sulfate (FES), ferric chloride (FEC), and gypsum (GYP) at 0, 5, 15, and 25% w/w. In order to study the effects of acidification, the same properties were measured in aqueous extracts of broiler litter suspensions that were titrated to end-points 3, 4, or 6 with 0.5N HCl. Concentrations of MRP, DUP, Ca and Mg, were 61%, 53%, 3.8 times, and 2.6 times greater in extracts from suspensions acidified to pH 6 than at the original pH of 8.9. ALS, FES, and FEC reduced pH, and showed similar effects on WSP concentrations, which were greater than with GYP. The magnitude of the reductions in WSP by ALS, FES, and FEC is uncertain because the actual amount of WSP immobilized cannot be determined. This is because of two opposite effects: 1) Through adsorption, soluble aluminum and iron remove phosphates from solution, and 2) Through acidification, iron and aluminum compounds release phosphates to solution.  相似文献   

5.
Canada’s new Green Plan charts a course for dealing with environmental issues that will require an unflinching commitment to changes in thought, decision-making and action by all sectors of Canadian society. The five-year, $3-billion Plan lists 120 specific initiatives in eight areas of activity. It will enlist the participation of some 40 federal departments and agencies, alone, cooperatively or in creative partnerships with industry, the academic and scientific community, and citizens’ groups.  相似文献   

6.
This paper deals with the installation of electrostatic precipitators on a new oxygen lanced open hearth furnace. The considerations include the various factors pertinent in the design of the precipitators, i.e., gas volume, temperature, dewpoint, dust concentrations, oxygen lancing rates, etc., along with some comments on the operation of the units.  相似文献   

7.
Abstract

This study attempts to assess the effectiveness of control strategies for reducing volatile organic compound (VOC) emission from the polyvinyl chloride (PVC) wallpaper production industry. In Taiwan, methyl ethyl ketone, TOL, and cyclohexanone have comprised the major content of solvents, accounting for ~113,000 t/yr to avoid excessive viscosity of plasticizer dioctyl phthalate (DOP) and to increase facility in working. Emissions of these VOCs from solvents have caused serious odor and worse air quality problems. In this study, 80 stacks in five factories were tested to evaluate emission characteristics at each VOC source. After examining the VOC concentrations in the flue gases and contents, the VOC emission rate before treatment and from fugitive sources was 93,000 and 800 t/yr, respectively. In this study, the semiwet electrostatic precipitator is recommended for use as cost-effective control equipment.  相似文献   

8.
Biofilter technology has been applied recently to treating rendering odors. Soil beds are one class of biofilter but as yet have not been used for this application. Although wet scrubbers have been a traditional method of odor control, their capital and operating costs are impacting more severely. Soil bed systems are less expensive to install and operate.

A soil bed system was installed at a rendering plant in Arizona and has been in operation since September 1983. The soil bed treats 1100 m3/h (650 cfm) of cooker noncondensables with a surface area of 420 m2(4500 ft2). The pressure drop across the soil bed is 5 cm (2 in.) of water. Odor sensory testing with the MTRI forced-choice triangle dynamic olfactometer indicates an odor removal efficiency of 99.9 percent is obtained with the soil bed. Soil bed odor removal efficiency is equivalent to or superior than that for incineration or scrubbing of high intensity odors from the rendering process. Recent experience during this past winter indicates a soil bed is a viable method for operation in a northern climate with severe winter weather conditions. Also, monitoring of the leachate from a soil bed indicated no contamination.  相似文献   

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Chlorinated atmospheric pollutants are presently receiving much attention because of expected chlorine-ozone interactions in the stratosphere.1,2 The fully halogenated pollutants,such as CCI3F, CCl2F2, and CCl4, have no known removal processes that operate in the troposphere. These compounds are accumulating on a global scale, their atmospheric mixing ratios having reached about 2 X 10-10 for CCl2F2,1.2 X 10-10 for CCl3F, and 9 X 10-11 for CCl4.3-5  相似文献   

11.
The body of information presented in this paper is directed to those individuals concerned with the control of air pollution emissions which occur as a result of the operation of by-product coke plants. It describes a new process which represents a major change in the charging operation wherein preheated coal can be charged to coke ovens via a closed pipeline system thus replacing the conventional larry charging car and thereby eliminating air pollution estimated to be as much as 70% of the total emissions from coke oven operations. Coal is dried and preheated in a continuous fluidized bed process utilizing products of combustion of coke oven gas. The coal is recovered in conventional cyclone collectors and conveyed to the ovens via a new and novel pneumatic conveying system where the gas used is superheated steam. Jet energy repeatedly thrusts the coal upward and forward through the pipe, obtaining a high efficiency of transport of solids ten times that of conventional systems. Major advantages of the process demonstrated to date include (1) elimination of emissions from charging, (2) reduction of emission from pushing, (3) improved battery top working conditions, (4) increased oven productivity as much as 45%.  相似文献   

12.
13.
Abstract

The purpose of the study was to quantify the impact of traffic conditions, such as free flow and congestion, on local air quality. The Borman Expressway (I-80/94) in Northwest Indiana is considered a test bed for this research because of the high volume of class 9 truck traffic traveling on it, as well as the existing and continuing installation of the Intelligent Transportation System (ITS) to improve traffic management along the highway stretch. An empirical traffic air quality (TAQ) model was developed to estimate the fine particulate matter (PM2.5) emission factors (grams per kilometer) based solely on the measured traffic parameters, namely, average speed, average acceleration, and class 9 truck density. The TAQ model has shown better predictions that matched the measured emission factor values more than the U.S. Environmental Protection Agency (EPA)-PART5 model. During congestion (defined as flow-speeds <50 km/hr [30 mi/hr]), the TAQ model, on average, overpredicted the measured values only by a factor of 1.2, in comparison to a fourfold underprediction using the EPA-PART5 model. On the other hand, during free flow (defined as flow-speeds >80 km/hr [50 mi/hr]), the TAQ model was conservative in that it overpredicted the measured values by 1.5-fold.  相似文献   

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ABSTRACT

A sorptive slurry bioscrubber adds powdered activated carbon (PAC) to a conventional suspended-growth bioscrubber. The activated carbon increases pollutant removal from the gas phase due to adsorption on carbon. The carbon is bioregenerated in the oxidation reactor and recycled to the scrubbing column. A three-stage, conventional bioscrubber was tested with and without carbon. The experiments showed that the PAC improved the removal efficiency of the system and that bioregeneration occurred. At an inlet gas-phase acetone concentration of 50 ppmv, the steady-state removal increased from 88 to 95% when activated carbon was added to the biological slurry.  相似文献   

16.
This report deals with the entrapment, pickup, and transfer of hot gases during a typical coke oven push. Background information that led to the development of the Great Lakes Coke Oven Pushing Emission Control System is presented along with the problems that were encountered and solved during the design, construction, installation, and start-up of a pilot plant entrapment structure on a battery of 40 Simon Carves coke ovens. This unique entrapment structure has operated successfully since April 1972, and has been visited by representatives from almost all coke manufacturers in the U.S., as well as interested groups from several foreign countries. In addition to these operation groups, we have been visited by various state and federal pollution authorities, such as the Environmental Protection Agency, Battelle Institute, and National Institute of Occupational Safety and Health. At the present time we are erecting a similar entrapment structure on the north side of our plant, comprising 18 Koppers and 35 Wilputte ovens.  相似文献   

17.
An activated carbon moving bed system (10 to 100 acf m air flow) was tested for controlling VOC emissions from a commercial aircraft painting facility. The cross-flow moving adsorbent bed showed a VOC collection efficiency in the 77.1 to 99.6 percent range over a superficial gas velocity range of 27 to 185 ft/min (0.14-0.94 m/sec). The collection efficiencies were neither affected by a change in carbon flow rates from 5 to 8 Ib/hr (2.3 to 3.6 kg/hr) nor by a change in the gas superficial velocity from 27 to 185 ft/min. The VOC concentration in the emission stream from the painting hangar was found to vary by at least a factor of 20 (from 0.18 to 15 ppm) both over the five month period (during which the 15 system tests of about three hours each were conducted) and within a single eight hour work shift.  相似文献   

18.
Abstract

To test the effectiveness of California’s vehicle inspection/ maintenance (I/M) program, exclusive of vehicle-owner intervention, a fleet of more than 1,100 vehicles that previously had failed California’s Smog Check test were sent to randomly selected Smog Check stations in the Los Angeles area for covert inspections and repairs. The two-speed idle test was used for repairs. For those vehicles that were repaired at the first inspection, their FTP emission reductions were 25%, 14%, and 11% for hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx), respectively, although emissions testing for NOx was not performed at the Smog Check stations. Idle HC and CO emissions increased for 35% and 43% of the vehicles, respectively, after repairs. This data set shows that most vehicles that fail the Smog Check inspection are only marginal emitters, with 61% and 44% of the total potential for HC and CO emission reductions, respectively, coming from only 10% of the vehicles that currently fail the inspection. When the vehicles were rank-ordered by idle emissions from dirtiest to cleanest, emission reduction costs for the highest-emitting 10% of the fleet averaged $l,100/ton and $250/ton for HC and CO, respectively, attributing all the costs to each pollutant exclusively. For the remaining vehicles, costs increased dramatically.  相似文献   

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