Nancy J. Sell

The agronomic landspreading of coal bottom ash: Using a regulated solid waste as a resource

Abstract Within the U.S., approximately 8860 Mg of dry coal bottom ash is generated daily, the majority of which is disposed of by landfilling. The disposal cost varies significantly depending on location. In Wisconsin, for example, in 1987 public landfill disposal costs ranged from U.S.

Methanol-gasoline blends: blending agents to prevent phase separation

8.90 to

Fly ash as a sorbent for the removal of biologically resistant organic matter

30 per Mg. However, bottom ash appears to be an acceptable soil amendment which may alter texture and improve tilth by making clay soils more friable and decreasing crust formation. If a generic exemption for this material can be developed with the appropriate regulatory bodies, use of coal bottom ash as a soil amendment has societal and economic advantages. This paper describes the key point of an agronomic management plan. An economic comparison indicates that, based on 1987 costs, agronomic use is only 38% as costly as landfill disposal.

SEDIMENTATION BEHAVIOR OF VARIOUS PULP FIBERS

Abstract The use of methanol-gasoline blends as automotive fuel is limited, in part, by phase separation at low temperatures. The separation temperature of these mixtures can be adjusted by varying the percentage of blending agent present. Two blending agents were considered in this study, tertiary butyl alcohol and isopropyl alcohol. Both were found to significantly lower the separation temperature, although, isopropyl alcohol is more effective, possibly due to its greater ability to form hydrogen bonds. Correlation equations were derived relating the percentage compositions and the separation temperature.

The potential for synfuels production from cellulosic papermaking wastes

Abstract Six different fly ashes, in both an untreated and an acidified form, were studied with respect to their ability to remove color and organic materials from a municipal waste treatment facility effluent. Color, fluorescence, and chemical oxygen demand were used to monitor the removal. The apparent predominant mechanism varies with the pH and the chemical characteristics of the ash. These mechanisms include carbon sorption, calcium precipitation of tannins and humics, sorption on the fly ash surface by silica, alumina, and/or iron oxide and, in the acidified situation, coagulation of colored colloids in the effluent dissolved from the fly ash. Some additional deleterious components are dissolved into the effluent during the treatment process. Many of these materials can, however, be removed by using a two-stage fly ash sorption process.Particularly of interest is the ability to remove over 90% of the boron from the effluent.

Lead contamination associated with snowmobile trails.

Abstract Wood pulp fibers form floes which settle by “zone settling.” These fiber floes do not exhibit Stokes’ Law settling behavior. A new filtration model was developed. This model describes quite well the settling of most types of pulp fibers, and its application generates a parameter, K’, which can be used to monitor pulp refining. However, decrilled samples, i.e., pulp from which fines have been removed, do not follow the new model. More work is needed to understand the settling behavior of fines-free pulp.

Energy conservation and dust production in wet rotary cement kilns

Abstract Papermaking wastes, available in large quantities, have the potential for providing the raw materials for production of commodity chemicals, many of which are suitable for fuels use. A number of techniques are being developed for the recovery of these chemicals. All methods involve three stages: pretreatment, hydrolysis, then fermentation. The hydrolysis techniques include using conventional and non-conventional pulping, acid hydrolysis, high temperature and pressure, microbial digestion (fermentation), or combinations of these. Several recent advances show potential for being cost effective. Estimated production costs for ethanol so produced range as low as 22.5¢/L (85 ¢/gallon U.S.).

MAPPS fluidized bed calcination of lime mud: modelling for design

Lead associated with one seasons use of a snowmobile trail was determined by atomic absorption. Pb in the snow and, particularly, in the associated soil/particulate matter was extremely high, ranging upward to 136 μg-atom Pb/m2 where the trail narrows to approximately 2 m. In comparison to these levels, the lead present in field soil due to automobile traffic on nearby roads was found to be negligible. Some possible environmental effects of this lead source are also discussed.

Effect of in-process treatment on contaminant levels during the recycling of paper-mill water streams

Abstract Energy conservation is currently a major concern of the cement industry. A comparison of data supplied by the U.S. Federal Energy Administration with that gathered in an extensive private study incorporating 29 wet cement plants indicates that a significant reduction of the energy consumed can be accomplished by decreasing the amount of dust generated in the process. Energy saving of 8 percent through dust suppression appears possible by increasing the slurry moisture and by using hammermills rather than impactors as the crushing technique.

The economic and energy costs of dust handling in the cement industry

Abstract The Institute of Paper Chemistrys MAPPS (Modular Analysis of Pulp and Paper Systems) program was used to model the operation and design of a fluidized bed calciner. In addition to the mass and energy balances, the model can be used to calculate the parameters such as minimum and maximum fluidization velocities, air compressor power requirements and bed size.