Shale Powder Research Articles

Effect of Electrostatic Interactions on Water Uptake of Gas Shales: The Interplay of Solution Ionic Strength and Electrostatic Double Layer

We conduct spontaneous imbibition experiments using different fluids (deionized, DI, water and brines) and different media (unwashed and washed shale powder) to study the wetting behavior of the shale samples from the Horn River Basin (HRB), a massive unconventional gas play in the Western Canadian Sedimentary Basin. As expected, unwashed shale powder imbibes DI water faster than brine. Surprisingly, washing the powders results in faster imbibition of DI water. The imbibition of DI water into washed shale powders, which have a reduced soluble/leachable ion content, cannot be fully explained by osmotic effects. We explain the observed imbibition profiles using the electrostatic interaction theory. We measure the ion concentration of the brines by ICP-MS analysis and determine the ionic strength, I, of the in situ formed brine. We also calculate the characteristic thickness of electrostatic double layer, κ–1, formed around the surface of charged shale powders. The results indicate that the imbibition rate d...

Bentonite-Free Water-Based Drilling Fluid with High-Temperature Tolerance for Protecting Deep Reservoirs

A bentonite-free water-based drilling fluid (BFDF) with high-temperature tolerance (up to 200°C) was developed for protecting reservoirs in deep wells. The fluid is composed of heatresistant polymeric thickener and starch, sodium sulfite, etc. A series of methods including environmental scanning electron microscopy (ESEM), linear expansion and hot-rolling dispersion test, and core-flow experiments and measurements of the rheological parameter, filtrate, and biotoxicity were used to evaluate the performance of the BFDF formulation. Laboratory results indicate that the fluid has excellent high-temperature tolerance. Its yield point and plastic viscosity ratio is up to 0.38 even after aging at 200°C for 16 h with API filtrate of 9.8 mL. Its apparent viscosity, plastic viscosity, and yield point at 180°C are 30 mPa·s, 17 mPa·s, and 14.5 Pa, respectively, which show its good well-cutting carrying performance and wellbore purification capacity. The BFDF formulation exhibits a strong ability to restrain the linear expansion rate of bentonite and shale powder, to improve cutting recovery, to protect the well reservoir by cutting down water blocking and lowering permeability damage, and to minimize biotoxicity with a high EC50 value and is suitable for drilling deep wells in environmentally sensitive areas.

Initiation, movement, and run-out of the giant Tsaoling landslide — What can we learn from a simple rigid block model and a velocity–displacement dependent friction law?

Tsaoling landslide is the largest and best documented landslide among several large landslides induced by the 1999 Taiwan Chi-Chi earthquake. Pliocene sedimentary rocks of about 125Mm3 in volume slid along very flat bedding planes dipping by 14° with an average speed of 35–40m/s for about 1650m, before hitting the bank of the Chinshui River during the landslide. Detailed analysis of DTMs before and after the earthquake using a GIS software leads to an accurate determination of the locations of the centroids of landslide mass, revealing the horizontal and vertical displacements of the 2524m and 524m, respectively. Those displacements and landslide mass give an apparent friction coefficient of 0.21 and the release of the potential energy of 1.6×1015J. We conducted rotary-shear high-velocity friction experiments on fault gouge from bedding-parallel faults under semi-wet conditions and at 3MPa normal stress corresponding to the overburden pressure of the landslide mass. We also compiled reported data on the frictional properties on shale powders and fault gouge from the landslide site under both dry and wet conditions, and proposed a velocity–displacement dependent friction law that can describe most experimental data. Newmark analysis of landslide motion with six scenarios for different landslide materials and conditions, assuming a simple rigid block sliding and using measured frictional parameters, revealed that the landslide did not occur with dry frictional properties, and that the landslide occurred at 38–39s with accumulated displacements of 0.62m–1.09m and reached at the river bank at 82–87s after the generation of Chi-Chi earthquake at its epicenter. Those timings are consistent with high-frequency signals at 32–40s and at 76s recorded at a nearby seismic station and with a survivor's witness that the landslide initiated 10s after he felt strong ground motion, possible S wave arrival at 25.2s. Slip-weakening is essential in initiating the landslide and low friction coefficient (0.08–0.1) allowed high-speed of the landslide possible. The landslide was caused by a few peaks of northeast-oriented strong accelerations of the ground motion. Frictional work during the sliding of the landslide mass was estimated to be of about 23% of potential energy, and the rest of the released energy is likely to have been consumed during the stopping phase of the landslide after hitting the river bank in complex processes such as fragmentation, heat dissipation, and spreading of the landslide deposits.

The role of stress on chemical compaction of illite shale powder

Abstract Experimental compaction curves for mud are key factors in sedimentary basin models but they are poor at predicting porosity evolution beyond 2.5 km depth, where chemical compaction dominates shale diagenesis. This study presents the results of experimental simulation of diagenesis and low-grade metamorphism of an illite shale powder. By applying amphibolite facies conditions using high-pressure–high-temperature deformation apparatus, the transformation of illite to phengite that takes place under anchizone and epizone metamorphic conditions could be accelerated and completed within laboratory timescales. In accordance with observation of naturally compacted shales, our experimentally compacted metapelites range in porosity from 1% to 16% and contain authigenic phengite, biotite, and quartz. By compacting illite shale powder under both lithostatic and non-lithostatic conditions, the role of stress or tectonic forces during diagenesis could be evaluated. Based on microstructural and chemical similarities we infer that both types of samples compact in the same way, indicating that chemical compaction is unaffected by differential stress. Basin evolution models can therefore extend the 1D generalization of the stress field to depths where chemical compaction takes place. However, as chemical compaction enhances mineral alignment, anisotropy of physical properties such as permeability and sonic velocities can change substantially.

Incorporação de pó de rocha sedimentar em massas para telhas cerâmicas - parte 1: efeitos nas propriedades físicas e mecânicas

Este trabalho tem por objetivo reformular uma massa típica de telhas de Campos dos Goytacazes, RJ, com adições de argilito em pó, rocha sedimentar comum em Itu, SP, e extensivamente utilizada na produção de cerâmica estrutural naquela região. Composições com argila plástica de Campos dos Goytacazes e 30, 40 e 50% em peso de argilito em pó foram preparadas e caracterizadas. As propriedades e características das massas com argilito foram comparadas às de uma massa para telhas da região norte-fluminense. Para a determinação das propriedades físicas e mecânicas foram utilizados corpos de prova preparados por extrusão e queimados nas temperaturas entre 800 e 1050 ºC. As propriedades tecnológicas avaliadas foram: densidade aparente, retração linear após secagem e queima, absorção de água e resistência à flexão. Os resultados demonstram que a utilização de argilito em pó pode melhorar as propriedades das telhas cerâmicas produzidas em Campos dos Goytacazes.

Research on Mixing Ratio of Waste Mud Brick

In order to achieve green building materials, energy conservation, waste reuse purposes. Use city sewage sludge as part of the raw materials for production of shale brick is studied by experiments adopted the different mixing ratio, find matching and the relationship between the compressive strength. Experimental results show that the shale powder to add quality percentage is 40% of dry sludge, formed a burning brick, brick of various performance accord with national standards, not only can save coal and mineral resources, improve the heat insulation brick, but also a lot of recycling of utilization of sludge.

Decoupling of paramagnetic and ferrimagnetic AMS development during the experimental chemical compaction of illite shale powder

Decoupling of paramagnetic and ferrimagnetic AMS development during the experimental chemical compaction of illite shale powder

Effect of Calcination Temperature on Pozzolanic Reaction of Calcined Shale Mortar

This study investigated the influence of calcination temperature on the pozzolanic activity of shale. Calcination temperatures of 500 °C, 600 °C, 700 °C, 800 °C, and 900 °C were used. The calcined shale powder was then passed through a No.200 sieve before being used to replace 20% of the cement in standard mortar samples. X-ray fluorescence spectrometery (XRF) was used to analyze the chemical composition of the calcined shale. In addition, the effects of replacing mortar with calcined shale were also examined with regard to setting time, pozzolanic activity, compressive strength, ultrasonic wave velocity, and the water absorption of the mortar. The test results demonstrate that the chemical composition of SiO2+Al2O3+Fe2O3 exceeded the 70% required by ASTM C618 specifications. The strength activity index (SAI) of calcined shale at 7, 28, 56 days exceeded 75%. At 28 days, the SAI values of samples produced with shale calcined at 700 °C and 800 °C exceeded 99%. After 28 days, the SAI, water absorption, and ultrasonic wave velocity values were nearly identical to those of control samples produced using only cement. Among all shale samples, those calcined at temperatures between 700 and 800 °C demonstrated the highest pozzolanic activity.

Improvement of water vapor adsorption ability of natural mesoporous material by impregnating with chloride salts for development of a new desiccant filter

The aim of this study is the development of a new adsorbent for the desiccant material which can be regenerated by the domestic exhaust heat by using natural mesoporous material, Wakkanai siliceous shale. To improve this shale’s performance to adsorb/desorb the water vapor, lithium chloride, calcium chloride or sodium chloride was supported into the mesopores by impregnating with each chloride solution. Especially sodium chloride was effective to increase the water vapor adsorption amount 5–7 times of that of natural shale in the relative humidity range from 50 to 70%. Moreover, the appropriate impregnating concentrations were determined as 5wt% from the relationship between the maximum water vapor adsorption amount and the mesopore volume. Based on these results, a new desiccant filter has been developed by impregnated original paper with lithium chloride and sodium chloride. This paper contained shale powder in the synthetic fibers. The dehumidification performance of this filter was evaluated under the simulated summer condition in Tokyo. From the cyclic adsorption/regeneration test, this shale and chlorides filter could adsorb and desorb 60 g/h water vapor repeatedly at the regeneration temperature of 40°C. On the other hand, a silica gel filter and a zeolite filter adsorbed and desorbed only 10 g/h and 25 g/h, respectively. These results suggested that the shale impregnated with the chlorides has the best dehumidification ability as a new desiccant material. Further, the desiccant filter made from the shale will achieve the effective use of the low temperature exhaust heat.

Organic substance as a collector of recoil atoms234Th(234U) in black shales

The content and isotopic composition of uranium extracted under various leaching and extraction conditions from the dyctionemic shale from Estonian deposits are determined by alpha-spectrometry. The interaction of uranium with organic matter (OM) was confirmed by a correlation between the specific radioactivity of uranium and contents of OM in the fractions obtained by electrostatic separation of the ground shale powder. Correlation between the results of two different analytical schemes is shown. The thickness of uranium phase layer deposited on organic matter in two parts of the seam is compared.

Calorimetric determination of the heat of retorting oil shales to 773 K

The heat of retorting raw oil shale from 298 to 773 K was determined using a Calvet-type, high-temperature calorimeter. Samples from a float and sink separation procedure were used to span a wide range of kerogen/mineral contributions: Colorado Green River shale, 87–340 1 tonne −1; Australian Rundle shale, 33–255 1 tonne −1. Small samples (40–100 mg) of dried shale powder were dropped into the calorimeter at 773 K, producing an endothermic peak in the thermopile signal. The height of the peak is a measure of the enthalpy of rapid processes (~ 120–180 s), while the peak area gives the total enthalpy over the entire run (~ 1.3–1.5 h). Besides the quantitative enthalpy values obtained, a comparison of the peak-height and peak-area values is a measure of the duration of the processes occurring in the samples upon rapid heating to 773 K. This comparison for the Rundle shale indicates slower inorganic processes occurring at this temperature.