High Temperature,High Pressure Electrostatic Precipitation

This paper presents the results of work conducted by Research-Cottrell under EPA contract 68-02-2104. The feasibility of electrostatic precipitation at temperatures and pressures varying from ambient condition to 1366°K and 3550 kPa, respectively, has been demonstrated in a laboratory wire-pipe electrode system. Stable corona discharges are obtained at all temperatures subject to appropriate choices of electrode dimension, polarity, and pressure. Current-voltage characteristics are reported for dry air, a simulated combustion gas, and a substitute fuel gas. The effects of temperature, pressure, electrode geometry and polarity on sparkover voltage, corona-starting voltage, and current are evaluated. A precipitator performance model is included to incorporate this data into a high temperature, high pressure precipitator design. This model has been evaluated for an electrostatic (HTHP) precipitator following a pressurized fluidized bed combustor at 1089 K and 920 kPa. It is recommended that prototype HTHP electrostatic precipitators be applied to pilot coal gasifiers and fluidized bed combustors to obtain detailed design data and to verify the accuracy of the performance model under actual operating conditions.     

Captive Insurance Companies and the Management of Environmental Risks

Recent publicity has focused on the crisis in the market for commercial liability insurance. Industries and professionals concerned with air pollution are among those facing an acute shortage of insurance coverage. Captive insurance companies are gaining popularity as a means of securing comprehensive pollution liability coverage. Captives are separate corporations established by companies with similar risk management problems to write policies covering pollution emissions. Federal tax law requires that captives be set up properly, with transfer and distribution of risk, before premiums paid by the member companies are deductible. Financial responsibility requirements of the EPA are being redesigned, and may be favorable to the use of captives. Six states and several off-shore countries have statutes allowing captive insurance companies. Attention to practical details can lead to success in using captives to secure business advantages as well as protection from the risk of environmental impairment. Several of such considerations are discussed in light of the tax, environmental, and state regulatory issues relevant to the question, with an eye toward giving practical legal advice for structuring captives.     

Investor attitudes toward the value of corporate environmentalism: New survey findings

During the past several years, an increasing body of evidence and opinion has formed concerning the relationships between advancements in environmental, health, and safety (EH&S) management and the financial performance of the organization. In recent work,¹ we have described a new theoretical model linking improvements in environmental management systems and environmental performance to corporate risk, stock volatility, and market value, as well as an empirical evaluation that validated our model. A number of other studies² have documented changes in the market value of corporate equity as a function of environmental accidents, incidents, and (conversely) accomplishments. These are in addition to the numerous examples presented in the literature and at EH&S conferences and symposia that suggest that concerted efforts to reduce the organization's environmental “footprint” can yield cost savings, increased market share, reduced time to market, and perhaps other financial benefits. Some have gone so far as to proclaim that a new era has begun, in which environment-friendly corporations will increasingly be recognized and rewarded by financial market participants, and organizations that lag behind will be severely penalized.³ This article documents a new survey undertaken to identify important environmental factors, if any, investors employ in evaluating the quality and worth of equity and debt financing instruments.     

Performance of a Pulse-Jet Filter At High Filtration Velocity II. Filter Cake Redeposition

Pulse-jet filter cleaning is ineffective to the extent that collected dust redeposits rather than falls to the hopper. Dust tracer techniques were used to measure the amount of redeposition in a pilot scale pulse-jet filter. A mathematical model based on experimental results was developed to describe dust transfer from bag to bag, redeposition on the pulsed bag itself, and migration to the dust hopper. Dust redeposition upon the pulsed bag increased markedly with increasing filtration velocity, whereas migration and redeposition on bags adjacent to the pulsed bag decreased. For high velocity pulse-jet filters to operate at lowest possible pressure drop, filter cake redeposition must be minimized.     

Inactivation of coliform bacteria in Black Sea waters due to solar radiation

The effects of solar radiation and temperature on bacterial die-off rates in Black Sea coastal waters using total coliform as the indicator organism were studied. Coliform die-off experiments were carried out in seawater samples collected along the coastline. The experiments were conducted in beakers filled with seawater that were kept at constant temperatures and exposed to solar radiation. The membrane filter technique was used for the coliform analysis. Temperature ranging between 9 and 26 degrees C and solar radiation between 20 and 60 cal/cm(2) h were tested. Experiments in the dark were also conducted to isolate the effect of solar radiation from the other factors and, furthermore, to determine the effect of temperature on bacterial die-off. The solar radiation was found to be the most significant factor affecting the mortality of coliform bacteria.     

Predictors of coping behavior after a layoff

In a longitudinal study of laid-off industrial workers, we examined the effects of individual differences and situational characteristics on individuals' use of six job loss coping strategies. In each case the predictors explained a significant portion of the variance (30–47 percent) although different predictors were significantly associated with each of the six coping strategies. The results also suggest that the use of problem-focused and symptom-focused coping strategies are complementary rather than mutually exclusive. The study's implications and directions for future research are discussed as well. © 1998 John Wiley & Sons, Ltd.     

Suppressor cells prevent host resistance to tumor growth

The role of immunosuppressor cells in preventing host immune rejection of tumor cells is described. The growth of Lewis lung carcinoma (3LL) in syngeneic C57BL mice is accompanied by a weak and transient anti-tumor cytotoxic response that is later on replaced by tumor-enhancing activity. This enhancing activity is correlated with the generation of suppressor cells in 3LL-bearing mice. Such suppressors were demon strated in two ways: (a) Elimination of the hydrocortisone(HC)-sensitive lymphoid population from tumorbearing mice (TBM) resulted in a significant increase in the anti-tumor cytotoxic response and in a marked delay in tumor development. It is assumed that HC inactivates precursors of suppressor lymphocytes whereas the mature suppressor cells themselves are HC-resistant. (b) The increased resistance against the tumor could be partially re-suppressed by restoring the HC-treated TBM with spleen or thymus cells from normal C57BL. Suppression, however, was more pronounced if the resistant mice were restored with spleen or thymus cells from TBM. HC-resistant spleen cells from TBM that appear to be enriched for mature suppressor cells were capable of suppressing in vitro the secondary sensitization of spleen cells from TBM against tumor cells.