Empirical Relationships between Observed Ozone Concentrations and Geographical Areas with Concentrations Likely to Be above 120 ppb

The extent to which existing ozone monitoring data can be used to represent concentrations outside the area immediately surrounding a monitoring station is investigated. The results should be of Interest to those who wish to define areas within which standards are likely to have been exceeded. Relationships are established between the observed second-maximum hour-average ozone concentrations and the area within which It is possible to state with reasonable probability that National Ambient Air Quality Standards (NAAQS) have or have not been exceeded. All pairs of SAROAD stations (Storage and Retrieval of Aerometric Data) separated by 500 km or less which had nearly complete annual data sets were considered for the years 1974 through 1977 to determine the probability that the NAAQS would be exceeded at one station of the pair, given station separation and the observed second-maximum hourly ozone concentration at the other station. The resulting relationship was applied to SAROAD data for 1977, and circles were drawn around each SAROAD monitoring site to show the area within which it is 90% probable that the 120 ppb NAAQS was exceeded during 1977.     

A Comparison of Two Techniques for the Collection and Analysis of Polynuclear Aromatic Compounds in Ambient Air

A demonstration of the GHEMFIX solidification/stabilization process was conducted under the United States Environmental Protection Agency’s (EPA) Superfund Innovative Technology Evaluation (SITE) program. The demonstration was conducted in March 1989, at the Portable Equipment Salvage Company (PESC) uncontrolled hazardous waste site in Clackamas, Oregon. Waste containing lead, copper, and polychlorinated biphenyls (PCBs) from four different areas of the site were treated. Results showed substantial reduction of leachable lead and copper between the untreated waste and treated waste utilizing the EPA Toxicity Characteristics Leaching Procedure (TCLP) test. The effectiveness of this process for immobilizing PCBs could not be determined since the raw waste did not leach PCBs at high concentrations, utilizing the TCLP test. Data from other leaching tests for lead and copper would need to be utilized as input into a site specific groundwater model to determine whether solidification/stabilization would be an acceptable remedy for the site. Physical testing results indicated durability in exposed conditions.     

The Everchanging Air Pollution Control Market

While the United States is the largest single market for air pollution control equipment, it constitutes only about one-third of the total world market. This overview explores the legislative, economic, and technological factors that affect those markets.     

Electrostatic Stimulation of Fabric Filtration

The concept of electrostatic stimulation of fabric filtration (ESFF) has been investigated at pilot scale. The pilot unit consisted of a conventional baghouse in parallel with an ESFF baghouse, allowing direct comparison. All results reported in this paper are for pulse-cleaned bags in which the electric field was maintained parallel to the fabric surface. The performance of the ESFF baghouse has been superior to the parallel conventional baghouse by several measures. The ESFF baghouse demonstrated: (1) a reduced rate of pressure drop increase during a filtration cycle, (2) lower residual pressure drop, (3) stable operation at higher face velocities, and (4) improved particle removal efficiency. These benefits can be obtained with only minor modifications to conventional pulse-jet hardware and at low electrical power consumption. The indicated ability to operate at increased face velocities with only modest expenditure for electrical hardware leads to very favorable economic projections.     

Pollutant Removal from Wood and Coal Flue Gases by Soil Treatment

If many homeowners convert to solid fuels for heating, residential flue gases will be a large source of air pollution. Control of this pollution requires an inexpensive, reliable, and effective method of flue gas treatment. One such method is to force flue gases through soil beds. Such soil treatment removes all detectable smoke, odor, and polynuclear organic matter (POM), up to 97% of the CO, and at least 97% of the SO₂ from flue gases of wood and coal combustion. The technique is low cost, reliable, almost maintenance-free, and also appears suitable for other small point sources of air pollution.     

Comparison of Air Pollutant Emissions from Vaporizing and Air Atomizing Waste Oil Heaters

Information presented in this paper is directed to individuals concerned with emissions from combustion of waste crankcase oil for space heating. Studies were performed to characterize gaseous and particulate emissions and vaporizing pot solid residues resulting from the combustion of waste crankcase oil. Two types of waste oil burners were tested. One was a vaporizing oil burner rated at 35.2 kW (120,000 Btu/h heat input), and the other was an air atomizing oil burner rated at 73.3 kW (250,000 Btu/h heat input). Except for NO_X and SO_X, gaseous emissions were similar to those from conventional distillate oil combustion. NO_X and SO_X emissions were higher due to higher fuel nitrogen and sulfur concentrations. Waste oil from automotive use showed higher inorganic levels than crankcase oil used for truck engine lubrication. Both burner types discharged high levels of metallic species, but the air atomizing unit had much higher stack emission levels than did the vaporizing pot system. Also, particulate loading levels were an order of magnitude higher for the air atomizing burner than for the vaporizing pot burner when firing the waste oils. However, the vaporizing pot burner generated a waste residue containing the majority of its elemental emissions. Elements which exceeded threshold limit values for one or both heaters were cadmium, chromium, cobalt, copper, iron, lead, nickel, phosphorus, and zinc. However, the nickel and much of chromium appeared to be a sampling artifact caused by the stainless steel sampling system.     

Dry FGD at United Power Association’s Stanton Station

The United Power Association’s dry FGD system at Stanton, North Dakota was the first utility-operated lime spray dryer to be put into service in the United States. At 60 MW in size, it utilizes a single spray dryer vessel with three rotary atomizers and a ten-compartment fabric filter. It is currently operating at better than expected efficiency and Is meeting state and federal air quality requirements. Start-up and operation have shown that certain areas of design and operating conditions are critical to reliable operation. Flue gas, slurry, and water distribution and mixing must be carefully controlled if reliable, long term operation is to be achieved. Likewise, water chemistry Is Important in the reagent preparation equipment. Start-up of the system was accomplished In a step-wise fashion to bring the baghouse on line first, followed by the spray dryer. The spray dryer was operated at gradually lower outlet temperatures until design conditions were met. Measures taken since start-up to ensure reliable operation, and operation over an eighteen month period are discussed. Both particulate and SO₂ emission performance are evaluated.