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Viscous heating technology can destroy disease-causing microorganisms with no additional heat input. A laboratory-scale unit was constructed and tested with a simulant, and viscous heating achieved temperatures as high as 190°C. This study discusses additional variables – length and spacing – that are important to process design and optimization. The viscosity (μ) was described as a function of shear rate (γ̇); μ = 140 Pa s for t = 0 s and μ = 32*(γ̇)−0.6 Pa s for t > 0 s. The advantages of viscous heating to sanitize fecal mass are presented. The results show temperature gradient is more sensitive to changes in gap spacing than reactor length. For high throughput, the viscous heater length must be increased to provide fluid sufficient residence time to achieve the desired effluent temperature.

Highly viscous substances, such as feces, produce significant heat when layer deformation occurs. We describe the use of viscous heating sufficient to destroy disease-causing microorganisms and whipworms in feces. Computational fluid dynamics (CFD) was used to evaluate preliminary design and provide initial geometric specifications for a laboratory-scale unit. The laboratory device has a rotating core separated from a fixed shell wall by a defined space. Data were obtained over a range of operating conditions with simulant materials. The CFD model was validated with the experimental results. The temperature observed with the smallest spacing was 190 °C. Alternative geometries are considered for high-volume sludge processing. Potential design modifications include enhancing efficient water evaporation and recovery.

Interfacial contamination of batches of refined petroleum products transported through multiproduct pipelines is a long standing problem in the petroleum industry. Determination of the extent of mixing depends on various factors including fluid properties, operating conditions and flow regimes. The convective-diffusion model along with a fictional parameter, known as the axial dispersion coefficient introduced by Sir G. I. Taylor, is the commonly employed methodology to evaluate longitudinal mixing. However, the model was formulated with a uniform turbulent or laminar flow across the entire flow field. It is argued that the assumption of a uniform flow regime leads to inaccuracies in predicting the extent of contamination at the interface. This study incorporates both the turbulent and the viscous effects in predicting the interfacial contamination volume. Taylor’s analysis of dispersion coefficients has been reviewed, and an improved model combining the weighted effects of the viscous boundary layer contributions and the turbulent core contributions to axial dispersion is proposed. The proposed model provides a possible explanation for the underlying physics of interfacial contamination in flow through straight pipes without pipe fittings and other devices. A comparison of the model predictions with literature data demonstrates the importance of considering both turbulent and viscous effects to achieve better overall prediction accuracy.

Low temperature ash (LTA) samples prepared from nine US coals were characterized by X-ray diffraction. X-ray fluorescence, and surface area analyses. The results showed that illite, kaolinite, quartz and pyrite are major components in LTAs and that SFe ratios of some LTAs decreased significantly after H2 treatment implying the occurrence of a partial reduction of pyrite during this treatment. Surface areas of LTAs increased drastically on H2 treatment but decreased after exposure to sulphur and nitrogen compounds in activity testing. Correlations for the surface areas of LTAs before and after H2 treatment were found in terms of clay content and element concentrations.

The ILWAS model has been enhanced for application to multiple-lake hydrologic basins. This version of the model has been applied to the Big Moose basin, which includes Big Moose Lake and its tributary streams, lakes, and watersheds. The basin, as defined, includes an area of 96 km2, with over 20 lakes and ponds, and 70 km of streams. Hydrologic and chemical calibrations have been made using data from seven sampling stations. When total atmospheric sulfur loading to the basin is halved, the model predicts, after four years of simulation, a decreasing sulfate concentration and to a lesser extent a rising alkalinity at Big Moose Lake outlet. At the end of four years, the results show an increase in pH of 0.1 to 0.5 pH units depending upon season.

The precipitation pH measured at the Woods Lake station in the Adirondack Mountains of New York fluctuated between 3.4–5.5 with a mean of 4.2 for the period extending from Mar. 1978–Dec. 1981. An analysis has been performed to identify the chemical factors causing these pH fluctuations. The pH of precipitation can be calculated from the sum of strong acid anions less the sum of base cations. The data showed that the sum of base cations increased with the sum of acid anions. However, there was only a 0.4 equivalent increase in base cations per equivalent increase in acid anions. Thus, precipitation in the Adirondacks was always acidic (pH

Precipitation chemistry from different regions of the Continental United States is characterized in terms of a graph of annual mean μ (+) vs μ(−), where μ (+) = Ca2+ +Mg+2 + NH+4 + K+ and Na+,and σ (−) = SO2−4 + NO −3 + Cl−; concentrations are given in μeq. l−1. Sites receiving acid precipitation (pH 4.5) tend to cluster near a line of slope one. Four regions. North Central (Minnesota, Wisconsin), Midwest (Illinois, Ohio), East Central (North Carolina, Virginia), and North East (Pennsylvania, New York, Vermont, New Hampshire, Maine) are presented as areas in terms of minimum and maximum μ (+) and μ (−) values. Seasonal variations of μ (+) and σ (−) tend to occur along lines of constant slope within these regions. The results from the last decade have been compared with the few measurements from the 1950s. Although one possible interpretation from this comparison is that σ(−) has increased in one or more of the regions considered, this view is tempered by the inherent difficulty in comparing single sites with regions.

The surface and outlets of two headwater lakes acidified during the 1978, 1979, and 1980 spring snowmelt periods. The decrease in pH was accompanied by an increase in nitrate whereas the other strong acid anion, SO42−, remained relatively constant. Chemical mass-balance calculations, using data from the Integrated Lake–Watershed Acidification Study, indicate that the peak in acidification observed in the Adirondack Mountains in the spring is caused by (1) a dilution of base cations (Ca2+, Mg2+, Na+, and K+) and associated alkalinity by snowmelt, (2) an increase in NO3− concentration in the acidified portion of the lakes, and (3) the constant elevated concentration of SO42−. At Woods Lake, the NO3− that accumulated in the snowpack plus that deposited from the atmosphere during snowmelt was sufficient to account for the increased NO3− in and transported from the lake. At Panther Lake, an additional source of NO3− was needed and was believed to be contributed by nitrification in the upper soil horizons. If atmospheric deposition of sulfur is reduced, low-alkalinity systems like Woods and moderate-alkalinity systems like Panther will be less likely to develop strong acidity during spring acidification.

Low molecular weight polybenzopinacols were obtained by the photolytic coupling of m- and p-dibenzoylbenzene and 4,4′-dibenzoyldiphenyl ether in isopropanol, tetrahydrofuran–isopropanol, benzene–isopropanol, and benzene–ethanol solutions. The polypinacols were soluble in common organic solvents such as tetrahydrofuran, ether, and benzene. The inherent viscosities ranged from 0.06 to 0.14. Average molecular weight (Mn) data indicated that the polymers were mostly dimers and trimers.

Atmospheric inputs to Woods, Panther, and Sagamore Lake-Watersheds in the Adirondack Mountains of New York State were measured on a daily basis from March 1978 through December 1981. Precipitation quality was nearly identical at all sites on monthly and yearly bases; ion loadings to each watershed were principally controlled by the amount of precipitation. No yearly trend was evident for any ion concentration in wet deposition. Annual precipitation quantities showed little deviation from long-term averages for this region. Throughfall measured under various species of trees showed enrichment in most base cations and acid anions. Deciduous trees were found to increase the pH of incident precipitation, while coniferous canopies tended to decrease pH.

Precipitation over a forested watershed is altered by interaction with plant surfaces which act as a filter for airborne gases and particles. This results in a major transfer to the forest floor of materials captured, washed, and leached from the forest canopy. Sequential samples of wetfall and sequential samples of throughfall under deciduous and coniferous trees were collected and chemically analyzed for major anions and cations. A simple washoff, mixing model based on leaf area index was used to simulate throughfall chemistry and to decouple foliar exudation from dry deposition. Model results gave excellent predictions of the measured sequential throughfall using estimated values of dry deposition. The model can also be used to calculate dry deposition, if the sequential throughfall data and wetfall data are used as input variables.