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A pilot facility was designed and built in the Thermal Fluids Laboratory at the Savannah River Technology Center to demonstrate the slurry transport of ion exchange resins in and out of ion exchange columns.

This engineering analysis calculates minimum slurry transport velocities intended to maintain suspensions of solid particulate in slurries. This transport velocity is also known as the slurry flow critical velocity. It is not universally recognized that a transfer line flow velocity in excess of the slurry critical velocity is a requirement to prevent solids deposition and possible line plugging. However, slurry critical velocity seems to be the most prevalent objective measure to prevent solids deposition in transfer lines. The following critical velocity correlations from the literature are investigated: Durand (1953), Spells (1955), Sinclair (1962), Zandi and Gavatos (1967), Babcock (1968), Shook (1969), and Oroskar and Turian (1980). The advantage of these critical velocity correlations is that their use is not reliant upon any measure of bulk slurry viscosity. The input parameters are limited to slurry phase densities and mass fractions, pipe diameter, particle diameter, and viscosity of the pure liquid phase of the slurry. Consequently, the critical velocity calculation does not require determination of system pressure drops. Generalized slurry properties can, therefore, be recommended if the slurry can be adequately described by these variables and if the liquid phase viscosity is known. Analysis of these correlations are presented, indicating that themore » Oroskar and Turian (1980) models appear to be more conservative for smaller particulate sizes, typically those less than 100 microns diameter. This analysis suggests that the current Tank Farms waste compatibility program criteria may be insufficient to prevent particulate solids settling within slurry composition ranges currently allowed by the waste compatibility program. However, in order to relate a critical velocity associated with a certain slurry composition to a system limit, a means of relating the system capabilities to the slurry composition must be found. Generally, this means expressing the bulk or effective viscosity of the slurry being transferred to some more readily obtainable variable, such as slurry density or solids concentration. No universally recognized model exists to accomplish this, and there is great uncertainty among results from those models that do exist. Following this analysis of critical velocity correlations, a recommendation is made to revise the waste transfer compatibility program criteria relating to solids transport. The new criteria states that a special engineering evaluation is required for any waste transfer that involves particulate solid transport. This evaluation is needed to gain a measure of confidence that the critical velocity for a given slurry composition is within the capabilities of the transfer system.« less

An instrument has been developed which measures the solids concentration in slurry pipelines ranging in diameter from 5-150 cm. The operating principle is based on conductance, and in contrast to the gamma densitometer, the instrument does not require a nuclear radiation source. The instrument operates online, is non-intrusive, and provides real-time output. The instrument measures local concentration around the pipe periphery, and the local values are integrated to obtain the area-average concentration. A graphical display shows the variation of concentration from the top of the pipe to the bottom as well as the area-average concentration history. The instrument has been extensively tested in a slurry transport facility at the University of Florida as well as on-line at the Swift Creek phosphate mine in the state of Florida. Excellent performance of the instrument is observed over a wide range of operating conditions.

Over 100 million gallons of radioactive waste is currently stored in more than 270 large underground storage tanks at U.S. Department of Energy (DOE) nuclear reservations (Manke 1996). Of these tanks, 177 are located at the Hanford Site in southeastern Washington State (Gephart and Lundgren, 1996). These tanks have capacities ranging from 50,000 gallons to around 1,160,000 gallons. The waste in the Hanford Site tanks primarily exists as liquids (e. g., saturated salt solutions), sludge (a mixture of water and insoluble metal oxides and hydroxides), and saltcake (moist water-soluble salts such as sodium nitrate).

Mobilization of sludge waste stored in underground storage tanks can be achieved safely and reliably by sluicing. In the project discussed in this report, the waste in Hanford single-shell Tank 241-C-106 will be mobilized by sluicing, retrieved by a slurry retrieval pump, and transferred via an 1800-ft slurry pipeline to Tank 241-AY-102. A sluicing strategy must be developed that ensures efficient use of the deployed configuration of the sluicing system: the nozzle(s) and the retrieval pump(s). Given a sluicing system configuration in a particular tank, it is desirable to prescribe the sequential locations at which the sludge will be mobilized and retrieved and the rate at which these mobilization and retrieval processes take place. In addition, it is necessary to know whether the retrieved waste slurry meets the requirements for cross-site slurry transport. Some of the physical phenomena that take place during mobilization and retrieval and certain aspects of the sluicing process are described in this report. First, a mathematical model gives (1) an idealized geometrical representation of where, within the confines of a storage tank containing a certain amount of settled waste, sludge can be removed and mobilized; and (2) a quantitative measure of the amount of sludge that can be removed during a sluicing campaign. A model describing an idealized water jet issuing from a circular nozzle located at a given height above a flat surface is also presented in this report. This dynamic water-jet model provides the basis for improving the geometrical sluicing model presented next. In this model the authors assume that the water jet follows a straight trajectory toward a target point on a flat surface. However, the water jet does not follow a straight line in the actual tank, and using the true trajectory will allow a more accurate estimate of the amount of disturbed material. Also, the authors hope that developing accurate force and pressure fields will lead to a better description of the scouring process and more realistic material removal rates.

The retained gas volume can be estimated by several methods. All of these methods have significant uncertainties, but together they form a preponderance of evidence that describes the gas retention behavior of the tank. The methods are (1) an increase in nonconvective layer thickness; (2) a waste surface level rise (surface level effect [SLE] model); (3) the barometric pressure effect (BPE model); (4) direct void measurement; and (5) the consequences of the transfer process. The nonconvective layer thickness can be determined with sufficient accuracy to describe the overall waste configuration by means of temperature profiles or densitometer indications. However, the presence of a nonconvective layer does not necessarily indicate significant gas retention, and small changes in layer thickness that could quantify gas retention cannot be detected reliably with the methods available. The primary value of this measurement is in establishing the actual {open_quotes}fluffing factor{close_quotes} for thermal calculations. Surface level rise is not a useful measure of gas retention in Tank 241-C-106 (C-106) since the waste level fluctuates with regular makeup water additions. In Tank 241-AY-102 (AY-102) with the existing ventilation system it should be possible to determine the gas retention rate within 30-60% uncertainty from the surface level rise, should a significant rise be observed. The planned ventilation system upgrades in AY- 102 will greatly reduce the exhaust flow and the headspace humidity, and the evaporation rate should be significantly lower when transfers begin. This could reduce the uncertainty in gas retention rate estimates to around {+-} 10%.

The main objective of this project was to conduct intensive research and development of the Coal Log Pipeline (CLP). Specifically, the R & D was to concentrate on previously neglected and insufficiently studied aspects of CLP which were deemed significant. With improvements in these areas, CLP could be implemented for commercial use within five years. CLP technology is capable of transporting coal logs for long distances. The many potential advantages of CLP over truck and railroad transportation include: lower freight costs, less energy consumption, less air pollution, decreased environmental problems, increased safety, and improved reliability. Previous studies have shown that CLP is advantageous over slurry pipeline technology. First, CLP uses one-third the water required by a coal slurry pipeline. Second, CLP provides easier coal dewatering. Third, the CLP conveying capacity of coal is twice as much as a slurry transport line of equal diameter. In many situations, the cost for transporting each ton of coal is expected to be less expensive by CLP as compared to other competing modes of transportation such as: truck, unit train and slurry pipeline.

Wastes stored in Hanford Tank 241-SY-102 are planned to be retrieved from that tank and transferred to 200 East Area through the new pipeline Replacement Cross Site Transfer System (RCSTS). Because the planned transfer of this waste will use the RCSTS, the slurry that results from the mobilization and retrieval operations must meet the applicable waste acceptance criteria for this system. This report describes results of the second phase (the detailed assessment) of the SY-102 waste retrieval study, which is a part of the efforts to establish a technical basis for mobilization of the slurry, waste retrieval, and slurry transport. Hanford Tank 241-SY-102 is located in the SY Tank Farm in the Hanford Site`s 200 West Area. It was built in 1977 to serve as a feed tank for 242-S Evaporator/Crystallizer, receiving supernatant liquid from S, SX, T, and U tank farms. Since 1981, the primary sources of waste have been from 200 West Area facilities, e.g., T-Plant decontamination operations, Plutonium Finishing Plant operations, and the 222-S Laboratory. It is the only active-service double-shell tank (DST) in the 200 West Area and is used as the staging tank for cross-site transfers to 200 East Area DSTs. The tank currently stores approximately 470 kL (125 kgal) of sludge wastes from a variety of sources including the Plutonium Finishing Plant, T-Plant, and the 222-S Laboratory. In addition to the sludge, approximately twice this amount (about 930 kL) of dilute, noncomplexed waste forms a supernatant liquid layer above the sludge.

Numerous studies (Section 8) have,addressed the Theological properties of simulated process slurries at the Savannah River Laboratory for the Defense Waste Processing Facility and at Pacific Northwest Laboratory`(PNL) for the Hanford Waste Vitrification Plant (HWVP). These studies were reviewed to summarize existing data applicable to HWVP design. The reviewers determined that the existing data provide important information on the effects of feed variability, solids loading, temperature, formating, pH, and scale-up. However, these data cannot serve as a basis for fundamental slurry transport calculations because data are not reported in sufficient detail over a range of shear rates and in appropriate terms to be sufficient for transport calculations.

This activity supports the retrieval data quality objective (DQO) process by identifying the material properties that are important to the design, development, and operation of retrieval equipment; the activity also provides justification for characterizing those properties. These properties, which control tank waste behavior during retrieval operations, are also critical to the development of valid physical simulants for designing retrieval equipment. The waste is to be retrieved in a series of four steps. First, a selected retrieval technology breaks up or dislodges the waste into subsequently smaller pieces. Then, the dislodged waste is conveyed out of the tank through the conveyance line. Next, the waste flows into a separator unit that separates the gaseous phase from the liquid and solid phases. Finally, a unit may be present to condition the slurried waste before transporting it to the treatment facility. This document describes the characterization needs for the proposed processes to accomplish waste retrieval. Baseline mobilization technologies include mixer pump technology, sluicing, and high-pressure water-jet cutting. Other processes that are discussed in this document include slurry formation, pneumatic conveyance, and slurry transport. Section 2.0 gives a background of the DQO process and the different retrieval technologies. Section 3.0 provides the mechanistic descriptionsmore » and material properties critical to the different technologies and processes. Supplemental information on specific technologies and processes is provided in the appendices. Appendix A contains a preliminary sluicing model, and Appendices B and C cover pneumatic transport and slurry transport, respectively, as prepared for this document. Appendix D contains sample calculations for various equations.« less

Slurry-transport and -settling experiments were conducted to improve current descriptions of proppant transport and the results were used to formulate a new slurry-transport model incorporated into a fully 3D fracture simulator. The model was tested and verified vs. experimental observations of slurry transport in a 4 × 16-ft slot model. Results of the study indicate that proppant-slurry transport can be modeled accurately by accounting for the effects of single-particle settling, density-driven flow, particle-velocity profiles, and slurry rheology

The gamma emission imaging technique has been effectively applied for determination of the slurry radial flow pattern and mixing profile within the ball charge in a wet laboratory ball mill. Aqueous technetium, Tc99m radioisotope that emits 140 keV photons with a short half-life of 6.02 h, was utilized as a flow follower while the glycerol–water mixture was used to mimic the motion of the actual slurry as found in full scale systems. Tests were conducted under two different slurry viscosity conditions for two mill speed levels. Both qualitative and quantitative information of the slurry radial flow and mixing behaviour inside the mill were obtained. The slurry flow and mixing behaviour displayed a marked dependence on the mill speed and slurry viscosity. The slurry mixing time in the ball charge varied directly with the slurry viscosity but inversely with the mill rotational speed.

This paper reviews some of the problems limiting broad manufacturing implementation of chemical mechanical polishing (CMP) as a planarization process for interlevel dielectrics. We examine the mechanism whereby polish rates tend to decrease as the polish pad ages, and propose an explanation based on slurry transport. We review a simple theory which provides an understanding in terms of basic mechanical principles of how CMP produces its planarizing effect. Finally, we demonstrate a method capable of providing a quantitative measure of planarity.

An optical technique for flow diagnostics is developed to study the slurry transport on the surface of a pad and in an inter-pad-wafer region during chemical mechanical polishing. In this paper, we show that the variations in mean gray scale and nonuniformity with the wafer and pad rotation speeds agree in trend with the existing data of removal rate and nonuniformity for a 150 mm wafer. The simulation results of wafer-scale-averaged slurry shearing stress and nonuniformity also agree in trend with the data of mean gray scale and nonuniformity for a 200 mm wafer. The present flow diagnostics technique can be further used for the optimization of slurry injection rate and injection position to simultaneously obtain a high removal rate as well as a low nonuniformity. In this paper, we also show the optimum slurry injection rate.

Understanding the fluid dynamics, specifically the extent of flow nonidealities during chemical mechanical polishing ~CMP! is essential for maintaining a stable and predictable process especially as film thicknesses continue to decrease and wafer sizes continue to increase in accordance with the International Technology Roadmap for Semiconductors (ITRS). 1 Previous research indicates that slurry distribution under the wafer significantly influences the process. 2-4 Despite a wide consensus that slurry transport is a critical parameter, limited experimental research has been performed on slurry flow under the wafer. The purpose of this study is to develop a greater understanding of fluid dynamics using lubrication theory and the residence time distribution ~RTD! technique to determine the vessel dispersion number at a variety of operating parameters. By employing classical RTD techniques coupled with well-defined vessel dispersion models for nonideal reactors, this study quantifies the extent of axial dispersion ~and therefore flow nonideality ! as functions of slurry flow rate, wafer pressure, and pad-wafer velocity. The dispersion model is used to describe nonideal reactors, where the axial dispersion is superimposed on the plug flow of a fluid. The dispersion number is defined as

Due to the complexity of chemical mechanical polishing (CMP) in general and metal CMP in particular, modeling of CMP processes has been pursued only minimally in the literature. A fundamental understanding of these metal CMP processes is needed to minimize manufacturing and development costs that will continue to escalate as more devices migrate to subhalf-micrometer technologies where metallization schemes are more complicated. In this work, we have used two different models to characterize the tungsten CMP process. While the chemical Preston model is used to explain the effect of process parameters on the mean polish rate, the slurry transport model is useful in explaining the within wafer uniformity for the polishing process. We successfully validated the chemical Preston model using design of experiment (DOE) data and demonstrated the importance of slurry transport and the pad to wafer gap, to the within wafer uniformity for the embossed and regular politex polishing pads. We showed that better uniformity is obtained throughout the wafer with the embossed politex than the regular politex pad due to the presence of grooves in the embossed pad, which allow for better slurry transport across the pad. We effectively characterized the process and studied the effects of changing the various tool and process parameters on process performance.

In order to better understand the role of the fluid behavior in chemical mechanical planarization, we measured slurry transport beneath a glass wafer. We quantified the slurry transport using residence time distribution techniques and two measures of slurry transport efficiency, defined as the percentage of new slurry beneath a wafer, Slurry transport efficiency depended on platen speed flow rate and the conditioning method. We found that the average fluid residence times under the wafer decreased roughly linearly with platen speed. A threefold increase in platen speed decreased slurry mean residence time by a factor of 3.5. Changing the flow rate from 20 to 50 mL/min decreased the slurry mean residence times by 80%. In situ conditioning generally increased the slurry mean residence times and the amount of slurry mixing. In situ conditioning also decreased gradients in the slurry composition across the wafer, Pad topography had a large effect on the slurry gradients that developed across the wafer. Finally, we found that the slurry mixing history can be accurately modeled using a simple continuous function.

Ultrasonic waves are well suited for use in measurements that characterize multiphase fluids and flows. The waves can interrogate fluids and dense optically opaque suspensions. Transducers can give signals that penetrate vessels. Such transducers, together with supporting instrumentation, can provide on‐line real‐time measurements for use in process monitoring and control. Staff at the Pacific Northwest National Laboratory have developed a family of devices that measure fluid and slurry density, viscosity, flow rheology, particle size distribution, concentration, and velocity profiles. The transducers have been deployed on model systems to provide data that can be integrated to provide a more complete characterization of a process streams, including to detect time‐dependent changing interfaces caused by fouling or phase changes, to track process conditions during mixing, sedimentation, stratification, and slurry transport. A summary of the fundamental physical acoustics for wave‐process stream interaction...

REVIEW “SLURRY TRANSPORT USING CENTRIFUGAL PUMPS” Elsevier Science Publishers Ltd., Crown House, Linton Rd., Barking, Essex, IG11 8JU U.K., 1992, 355 pp. ISBN 1-85166-745-8 HB £ 52

In slurry transport, the critical velocity is defined as the minimum velocity demarcating flows in which the solids form a bed at the bottom of the pipe (bed load flows) from fully suspended flow. An analysis based on balancing the energy required to suspend the particles with that derived from dissipation of an appropriate fraction of the turbulent eddies is used to develop a correlation for prediction of the critical velocity. Comparison of the results with available experimental critical velocity data, relating to a rather wide variety of slurry systems, confirms that the present correlation does a superior job of prediction than all previously proposed critical velocity correlations.

A concept for residential refuse management is examined that calls for individual household refuse grinders, dilute slurry transport of ground refuse in the existing sanitary sewer system, and joint treatment of refuse and sewage at an expanded treatment facility that includes anaerobic digestion for methane generation. Hydraulic transport of ground refuse in existing sewer systems may be feasible only if both metals and glass are excluded, and a conventional collection of the nongrindable and bulky constituents of residential refuse will still be needed. The total 1973 cost of such a wet system is estimated at between –110 and –200 per household per year, of which –80-–105 is for grinding. This compares to a total cost for sewage and refuse collection and disposal under existing concepts of –40-–115 per household per year. If the cost of the grinder is excluded (individuals would purchase grinders), the 1973 wet system costs to the public sector would be on the order of –30-–90.

The ability of water to hold solid particulate matter in suspension, together with its fluidity, make it a desirable medium for use in the transportation of solid material in slurry pipelines. However in some areas, the vast amount of water required for this type of system may not be readily available. Presented here is a discussion of the technical and economic advantages of a slurry transport system, in which foam is used as the transport medium. Also included are the results of an experimental investigation designed to determine the feasibility and transport capacity of such a system. The results of the experimental investigation indicate that the use of foam in the transport of solid particulate material is technically sound, economically attractive and environmentally acceptable.

Summary A two-part study was conducted to define optimal gravel-pack procedures for some high-angle well completions in an area operated by Chevron U.S.A. Inc. In the first part of the study, gravel slurries were pumped through a 1,080-ft [329-m] tubing string to simulate actual slurry transport conditions in high-angle wells. The tubing string had an inclination of 80 deg. [1.4 rad] from vertical. Measurements were made to determine suitable viscosity and solids concentration for effective gravel transport. In the second part of the study, a frill-scale cased-hole completion model was constructed. Gravel slurries that had satisfactory transport performance were tested for packing characteristics in the model wellbore (completion interval). The need for special completion-interval geometry to obtain satisfactory packs was investigated. Results showed that high-viscosity carrier fluids (600 to 700 cp [0.6 to 0.7 Pas]) with high gravel concentrations (15 lbm/gal [1797 g/dm3]) provide good transport, but they are unsuitable for use in completion intervals in wells with angles of 80 deg. [1.4 rad] from vertical. Satisfactory transport and improved packing were achieved with lower carrier viscosity and concentration (300 to 400 cp, 4 lbm/gal [0.3 to 0.4 Pas, 479 g/dm ]). Special liner-tailpipe (washpipe) geometry considerations reported by previous investigators are required in conjunction with the optimal slurry properties defined in this study. Completion operations designed from results of this study have satisfactorily met general placement criteria. Field experience to date has been in wells with inclinations up to 80 deg. [1.4 rad] from vertical. Introduction The experimental study described in this report was designed to simulate actual high-angle gravel-pack completion operations scheduled for offshore wells in the U.S. gulf coast. Costs for the study were justified on the basis of high installation cost and the practical limitations of gravel-packing high-angle wells with then-existing techniques. The subject wells are generally directional and highly deviated, some with maximum deviation angles of 80 deg. [1.4 rad] from vertical. Our experience with high-angle wells such as these indicates that successful gravel-pack operations require special completion-design considerations. Previous studies, including one simulating large-diameter completions (11 in. [28 cm]), demonstrated placement problems as well as procedures required to overcome them and to place a gravel pack successfully in an 80 deg. [1.4-rad] wellbore. Tests were scaled to the dimensions of the actual wellbores because of closer tolerances (casing/liner) of the planned completions. Transport studies were made to identify problems in getting gravel to the completion zone. Three transport tests were performed in a 1,080-ft [329-m] tubing string, and five gravel-pack tests were run in an 80 deg. [1.4-rad] inclined, frill-scale, transparent 7-in. [17.8-cm] diameter model wellbore. The pumping tests were designed to show the effects of fluid viscosity and gravel concentration when they were pumped through a long, highly deviated tubing string. Pumping services were provided by oilfield service companies. The gravel-pack tests were run in a model wellbore having the same dimensions as downhole hardware commonly used by Chevron in one area of the gulf coast. The purpose of these tests was to determine the packing characteristics of the slurries studied in the long-tubing-string transport tests. The smaller casing size used to construct the model for this study distinguishes it from a previous study. All slurries were prepared with hydroxyethel cellulose (HEC) polymer. Low-, intermediate-, and high-viscosity carrier fluids up to 600 to 700 cp [0.6 to 0.7 Pa s] and gravel loads up to 15-lbm/gal [1797-g/dm ] concentration were studied. Use of such viscous fluids is state of the art for gravel packing. Because of their high carrying capacity, viscous carrier fluids result in shorter placement times. Primary job-design considerations for slurry packing include eliminating blank sections in the wellbore (leakoff through a liner or screen is required for pack dehydration). For somewhat vertical wells, a reserve of gravel above the perforations or open hole is required to accommodate after-pack settling, a characteristic of slurry packing. Routine success associated with slurry packing vertical and near-vertical wellbores is not obtained in highly deviated wellbores. Premature sandouts and after-pack settling often cause completion failure in deviated wells. Process variables available for overcoming these problems include carrier viscosity and liner-tailpipe annulus restriction. JPT P. 69^

An analysis was made of flocculated slurries outside of their compaction zone. The analysis of the flocculated slurries was complicated by the fact that measurements of solid particle size and density are not necessarily indicative of those of the flocs. Successful correlation of availabie experimental data appears to justify the supposition that the mechanism for particle suspension in conduits is similar to that in mechanical mixers. It was concluded that in order to transport a nonflocculated slurry outside its compaction zone without deposition of solids, it is necessary that the flow be turbulent. For very slowly settling particies in small lines, the only requirement is that the flow be fuliy turbulent. For more rapidly settling particles or larger conduits, greater eddying movements are necessary to supply the vertical forces that keep the particie in suspension. (P.C.H.)

Transportation of solids in form of slurries has become one of the most important unit operations in industries across several disciplines. In fact, the need is more pronounced in industries that are very important for human survival such as food processing, pharmaceuticals and energy (coal, oil and gas). A lot of work has been done in the past 30 years in understanding the factors affecting the deposition velocity of solids in slurries. Experimental observation and theoretical predictions pointed to mixture velocity and solid/fluid properties especially rheology of the resulting slurry to be the most important factors that dramatically affect particle motion and patterning. This paper presents a critical deposition velocity model and a “stability flow map” for complex rheology slurries. The critical deposition model utilizes a more robust generalized two-parameter rheology model to account for any given slurry rheology. The “stability flow map” demarcates the different flow patterns that may be observed at different mixture velocities and rheologies. On this map, the homogeneous slurries are predicted at low rheology and high mixture velocity, whereas heterogeneous slurries (with a concentration gradient) predicted at high rheology (yield stress effects). Sensitivity analysis was conducted on critical Reynolds number, particle density, carrier fluid density, generalized flow behavior index and pipe diameter. It was observed that increase in shear thinning behavior, particle density, pipe diameter and particle diameter led to a decrease in the laminar region and an increased unstable region. The model showed good performance when tested on glass and stainless steel beads test data available in open literature. Preliminary simulation with this map may help engineers select flowline size and carrier fluid rheology for a given type of solid particle.

In the literaturey many methods for the calculation of pipeline hydraulic transport of solids have been published. Their degree of exactness and applicability is variabie and therefore it is hard to the designer to make a convincible decision regarding their practical use. A new concept for the computation of slurry hydraulic transport in horizontal pipes proposed by O. Molerus and P. Wellmann based on numerous measurement data seems to provide a practicle method to predict the head loss in slurry pipeline transport. In this report the new method is introduced and a number of new experimental results to verify the new concept. Furthermore some suggestions are presented te impreve the new methed.

In the literaturey many methods for the calculation of pipeline hydraulic transport of solids have been published. Their degree of exactness and applicability is variabie and therefore it is hard to the designer to make a convincible decision regarding their practical use. A new concept for the computation of slurry hydraulic transport in horizontal pipes proposed by O. Molerus and P. Wellmann based on numerous measurement data seems to provide a practicle method to predict the head loss in slurry pipeline transport. In this report the new method is introduced and a number of new experimental results to verify the new concept. Furthermore some suggestions are presented te impreve the new methed.

The existing relationships based on Durand's method to predict pressure gradients for slurry flow in pipelines appear to be inadequate when accounting for a wide range of variables such as particle size and relative density as well as concentration. Using the coal, sand and iron ore data collected from various literature sources with the aid of non-dimensional analysis, new equations for the case of the heterogeneous flow regime were derived on the base of nondimensional parameters. The equations have the same structure for each material considered, but the coefficients are different.

A review is presented on slurry pipeline transportation of minerals and coal. Primary emphasis is put on past commercial applications, technical characteristics of the various pipeline system components, preliminary costing methodologies, and the hydraulic design criteria for both conventional as well as nonconventional slurries. A number of numerical examples are included for illustration purposes. Although a majority of the technical details pertain to cross-country, large-throughput coal slurry pipelines, appropriate generalizations are also offered for application to other types of slurry pipelines. Also assessed briefly are the overall energy, economic and environmental aspects of slurry pipelines.

The existing relationships based on Durand's method to predict pressure gradients for slurry flow in pipelines appear to be inadequate when accounting for a wide range of variables such as particle size and relative density as well as concentration. Using the coal, sand and iron ore data collected from various literature sources with the aid of non-dimensional analysis, new equations for the case of the heterogeneous flow regime were derived on the base of nondimensional parameters. The equations have the same structure for each material considered, but the coefficients are different.

Pneumatic transport is not a novel concept and commercial experience with pneumatic pipelines for short haul distances is plentiful. The list of applications is long and includes transporting ores, chemicals and pharmaceutical products, agricultural products, and domestic and industrial wastes. The most recent economic evaluation of pneumatic transportation of coal concluded that there are immediate advantages for short-distance transport (less than 100 miles) and that it is both technologically and economically feasible. That study also concludes that pneumatic transport has a higher potential and more promising profitability in long-distance applications than rail if new track and roadbed must be built. Some of the advantages of long and short distance pneumatic pipeline transport of coal compared to rail and slurry transport are given.

Test results of sludge slurry transport through the Interarea Transfer Line (IAL) Mock-up Facility showed little risk of plugging the interarea pipelines with sludge slurry. Plug-free operation of the pipeline was successfully demonstrated by worst case IAL operating scenarios. Pipeline pressure gradients were measured vs. flow rate for comparison with a computer model over a range of sludge slurry rheological properties. A mathematical computer model developed by L. M. Lee is included in this report which will predict pressure drop for Bingham plastic fluid flow in a pipeline. IAL pluggage situations and pumping requirements may be realized from this model. 4 refs., 11 figs., 2 tabs.

We demonstrate the advantages of a new hydraulic fracturing simulator comprising a fine-scale fracture hydrodynamics and in-situ kinetics model. In contrast to existing commercial modeling tools, it has a sufficient resolution and other functionality for adequate representation of modern stimulation technologies: pulsing injection of proppant, mixtures of multiple fracturing materials (fluids, proppants, fibers, etc.), materials degradation, etc. This simulator accounts for the influence of materials distribution on fracture propagation and calculates fracture conductivity distribution. We coupled it with a production simulation model and established a complete framework for hydraulic fracturing treatment design. In addition to the selection of the pumping schedule, this model can be used to define specifications for novel hydraulic fracturing materials. This is a step change tool for wellbore stimulation and production forecast.