Granite Processing Research Articles

Use of ornamental rock waste as a partial substitute for binder in the production of structural concrete

Abstract Due to the population increase, to the improvement of life conditions, to the elevation of levels of consumption and the growing industrialization of developing countries, it is estimated that the production of concrete will present significant increase in the next decades. The process of producing cement is responsible for approximately 5 % of the emissions of CO2, an expressive environment pollutant. In this context, this work presents an evaluation of the influence of partial substitution of cement by ornamental rock waste (ORW) on the physical and mechanical properties of concrete. ORW from a local marble and granite processing company was used. The waste was mineralogically characterized through X-ray diffraction (XRD) essays, energy-dispersive X-ray (EDX) microanalysis, and physically characterized through laser granulometry and specific mass. For this, was adopted a concrete trace as reference, produced with CP V-ARI cement (similar to ASTM Type III), from IPT dosage. Waste was used in proportions of 5 %, 7.5 %, 10 % and 12.5 % of substitution of cement by mass. Results were treated with ANOVA and multiple comparison of means, indicating a possibility of substitution of until 10% of cement by ORW, creating a concrete with proper resistance to Brazilian regulations regarding the classification as structural.

Assessment of magmatic versus post-magmatic processes in the Mueilha rare-metal granite, Eastern Desert of Egypt, Arabian-Nubian Shield

The Mueilha rare-metal granite, exposed in the central Eastern Desert of Egypt, is a post-collisional intrusion that formed in the final magmatic stage of the evolution of the Arabian-Nubian Shield. The Mueilha intrusion was emplaced as a high-level magmatic cupola into metamorphic country rocks. It consists of two cogenetic intrusive bodies: an early phase emplaced at shallow depth and now penetratively altered to white albite granite and a later phase of red granites emplaced at greater depth that better preserve magmatic features. The albite granite is less common and represents the upper margin of the Mueilha intrusion, the apex of the magmatic cupola. The red granites are volumetrically dominant and appears to have crystallized from the margins inward, forming a composite pluton zoned from muscovite granite to alkali feldspar granite. All parts of the Mueilha pluton appear to have been emplaced within a short time interval, before complete crystallization of the earliest phase. The geochemistry of the Mueilha granites is typical of rare-metal granites, characterized by high SiO2, Na2O + K2O, Nb, Rb, Ta, Y, U, Th, Sn, and W with depletion in P, Mg, Ti, Sr and Ba. They are weakly peraluminous and highly fractionated with A-type character. The chondrite-normalized REE patterns have strongly negative Eu anomalies, typical of highly differentiated granites that evolved through a transitional magmatic–hydrothermal stage. The primary magma feeding the Mueilha intrusion was generated by partial melting of the juvenile crust of the Arabian-Nubian Shield; it subsequently underwent extensive fractional crystallization and metasomatism by late- to post-magmatic fluids. Separation of fluids from the oversaturated melt promoted both diffuse greisenization and focused segregation of pegmatite and fluorite and quartz veins. Alkalis liberated from feldspars consumed by greisenization were redeposited during albitization in the uppermost part of the magma chamber. Despite penetration of the intrusion boundary by discrete dikes, veins, and aphophyses, diffuse alteration of the metamorphic country rocks is not apparent. Primary columbite-series minerals crystallized from the melt and were later partly replaced by secondary Nb and Ta minerals (fluorcalciomicrolite and wodginite) during hydrothermal alteration.

Numerical Simulation of the Influence of Flow Velocity on Granite Temperature Field Under Thermal Shock

Under thermal shock, the heat conduction between granite and fluid will lead to the redistribution of rock temperature field, while indoor thermal shock test cannot determine the distribution rule of temperature field inside granite accurately. In order to explore the influence of fluid velocity on the thermal shock process of granite, the temperature field and flow field is numerically simulated by COMSOL. The results show that heat transfer between granite and fluid is in the form of waves. In the process of heat conduction, the internal temperature and heat balance time of granite are greater than those of rock surface. The time of heat balance in rock provides reference for the design of indoor thermal shock test. After thermal shock, the temperature of granite is lower than the initial temperature. With the increase of fluid velocity, the thermal equilibrium time of granite decreases, and the final rock stable temperature decreases. According to the relationship between velocity and granite temperature, a linear correlation model between velocity and maximum instantaneous thermal shock velocity is proposed. It is also verified that the thermal fluid–solid coupling model of granite under thermal shock is feasible to simulate the heat conduction and temperature distribution in granite.

Monazite and cassiterite U[sbnd]Pb dating of the Abu Dabbab rare-metal granite, Egypt: Late Cryogenian metalliferous granite magmatism in the Arabian-Nubian Shield

The Abu Dabbab rare-metal granite in the Eastern Desert of Egypt is a highly-evolved alkali-feldspar granite with transitional magmatic-hydrothermal features. Extreme geochemical fractionation and the associated significant TaSn resource make the Abu Dabbab intrusion an important feature in the metallogenic evolution of the Arabian-Nubian Shield. UPb dating by laser ablation sector field (SF)-ICPMS analysis of igneous monazite yields a Concordia age of 644.7 ± 2.3 Ma, identical within uncertainty to a lower intercept Tera-Wasserburg isochron age of 644.2 ± 2.3 Ma obtained from hydrothermal cassiterite. Both ages place tight constraints on the timing of magmatic-hydrothermal processes in the Abu Dabbab granite which represents the oldest highly-evolved granite recognized so far in the Pan-African Arabian-Nubian Shield. Thus, the new ages also date the start of a period of late-orogenic metalliferous granite magmatism, when the basement of the Eastern Desert underwent a geodynamic transition from a compressive subduction-collision regime towards orogenic collapse in the late Cryogenian.

Epoxy Granite Properties using Indian Origin Granite

Precision machine tools are expected to operate at higher machine speed to produce precise products. Hence, its structures must have high structural stiffness and high damping along with dimensional and geometrical stability. Granite is the material used for metrological and precision machine manufacturing applications. Granite is also used in some of the high accuracy machine tool manufacturing. Considering the natural properties and limitations of granite a new emerging material named Epoxy Granite is evolved. In this paper, Epoxy Granite properties using Indian Black granite are studied. In particular, the maximum load-bearing and density of epoxy granite are focussed. Also, the combination which is best suited for the applications can be easily dragged out. Density is compared with maximum load-bearing and their relation is also put forward to simplify the selection process of epoxy granite.

Deformation and Acoustic Emission Characteristics of Cracked Granite during Creep

A series of multistage creep tests under different confining pressures with acoustic emission monitoring have been performed to investigate the deformation characteristic and failure process of cracked granite during creep. The critical axial strain of cracked sample showed an increasing tendency with the increase of confining pressure. In contrast, critical lateral strain experienced a process of descending first at low confinement and then remaining nearly constant at high confinement. Compared with loading‐cracked specimen, smaller critical axial strain, greater critical lateral strain, and higher lateral creep strain rate were found for unloading‐cracked specimen. Based on the spatial and temporal distribution of acoustic emission events, the cracking process during creep was analysed. The AE events with high energy are mainly concentrated at the final fracture area of the specimen. The higher the confining pressure, the more the AE events with low energy. Compared with the loading‐cracked specimen, the percentage of AE events with high energy is relatively small for the unloading‐cracked specimen.

Geology and Geochemistry of Schlieren cum Nebulites from Bauchi, Northeastern Nigeria

Bauchi is part of sheet 149NE which falls within the Northern Basement Complex of Nigeria. In this study, the area was mapped on a scale of 1:25,000. Samples were collected at the flanks of the outcrops, railway cuts, road cuts as well as blasting sites within the area. At each sampling point, two or more samples were collected based on morphological variations. The first and second order morphological classifications of migmatites as being metatexite or diatexite; banded orthogneiss, stromatic, schlieren or nebulite were used as the guiding principle. This technique was repeated for the rest of the sampling points in the area covering about fifteen (15) different locations. A total of 10 representative samples were studied geochemically. Together with the field relationship and morphological features, it was observed that the area has five (5) different lithologic units as metasediment (quartzite), melanocratic diatexite (schlieren), nebulites (Bauchite, quartz-diorite and granulitic granite) in a sequence of prograde metamorphism. The SiO2 content for the samples is between 64.2 and 77.8 wt %. Save for CaO, K2O and Sr, all the major oxides and minor elements show negative correlation with the silica. Zr and Hf show no clear correlation with the SiO2. Negative Nb, Ta, Ce and Y anomalies are characteristics of volcanic and plutonic rocks formed above subduction zones. It further signifies the contribution of mantle materials to the melt. All the samples are ferroan, which probably reflects derivation from reduced basaltic rock either by fractional crystallization or partial melting; and peraluminous which implies high development of K-Feldspar that is necessary for the formation of the nebulites. The rise in alumina and a corresponding decline in silica indicate fractionation which is yet against normal granitization process (magmatism).

Parameter analysis and modelling of grinding special-shaped granite by diamond tools based on a robot stone machining system

The processing parameters of special-shaped granite processing by robots are still determined artificially and the machining efficiency and quality are limited. To address this challenge, in this paper, the grinding process was divided into rough machining and finish machining with different diamond tools and parameters. The relationships among processing parameters, forces and errors of the cutting depth in rough machining and the relationships among processing parameters, contour errors and surface roughness in finish machining were investigated. Based on the experiments, the artificial neural networks of the two processes were conducted separately, having high precision with errors less than 9% and 6%, which can be used to direct the selection of the parameters. This research can be applied directly during production to improve the processing efficiency and quality.

Methodologies for evaluating sawability of ornamental granite and relation modeling combining sawability with environmental impacts: An application in a stone industrial park of China

Abstract Due to the rapid economic development and urbanization in China, the ornamental stone industry is developing fast, resulting in several environmental problems. Compared with the marble, granite is more difficult to be processed with greater environmental impacts. At present, many advanced and clean technologies are emerging in granite processing field, such as new processing technologies, wastewater treatment system and solid waste reusing technologies. Therefore, a reasonable clean technology planning is crucial for granite processing companies to achieve cleaner production (CP) mode. The purpose of this study is to develop a methodology for evaluating sawability of ornamental granite and constructing the relational model between sawability and environmental impacts from sawing process. The relation model can be used to predict key environmental impacts and support the clean technology planning. This paper firstly develops a characterization mechanism to describe the granite sawability based on Multiple Attribute Decision Making (MADM) theory. The characterization mechanism provides a specialized score system as uniform metric of sawability for ornamental granite. Secondly, definition of sawability function is proposed in this paper to make sawability evaluating process with better operability and applicability. The method for developing the sawability function is investigated combining the characterization mechanism with the design of experiment (DOE) theory. Thirdly, relational models between the granite sawability and the key environmental impacts are investigated by numerical fitting. The uncertainty analysis method for the modeling process is also provided in this paper. The methodology has been applied in a granite processing plant in Laizhou stone industrial park in Shandong province of China. Energy consumption, water consumption and solid waste generation of the plant have been estimated based on the relational models. The models have been proved to be helpful in providing basis for the cleaning technology planning in the plant.

ANALISIS BREAK EVEN POINT HASIL PELEDAKAN BATU GRANIT PADA UNIT PELEDAKAN PT ADITYA BUANA INTER DI KECAMATAN MERAWANG KABUPATEN BANGKA

The process of mining granite in PT Aditya Buana Inter is mined with an open pit (quarry)system. The granite blasting system at PT Aditya Buana Inter consisted of 5 blasting and with 386holes of explosive holes obtained, the total institutional volume was 199.996 m3 (BCM) and the totalvolume of blasting was 13001, 7 m3 (BCM) of the target company of 16,000 m3 (BCM) / month. Drillingand blasting activities to produce blasting volumes of course there are factors that influence theseactivities. Factors that influence drilling and blasting activities affect the costs incurred and the volumeof blasting results produced, the factors that influence these activities include: weather, frontconditions, equipment damage, less optimal blasting geometry measurements. The activity is certainlynot inseparable from the costs that must be incurred by PT Aditya Buana Inter both fixed costs andvariable costs. The total costs incurred by PT Aditya Buana Inter on September 2, 2018 to October4, 2018 are Rp 352,677,200.00 which includes fixed costs of Rp 170,616,020.00 and variable costs(variable costs) of Rp 182,061,000.00, and variable costs per m3 the volume of blasting yield is Rp14,003 /m3. Break even points obtained from calculations for units are 812,468 m3 and in rupiah Rp181,992,901.00. PT Aditya Buana Inter income from the sale of split stone is Rp 472,846,080.00obtained from the sales volume of 2110.92 m3 with a selling price of Rp 224,000 /m3, the profit (L)obtained is Rp 90,610,140.00. Calculation of Break Even Point analysis can determine the minimumamount of volume of rock from the blasting that will be produced and to find out the condition of thecompany not making a profit and also not losing.

Characterizing three-dimensional creep of Beishan granite by the variable-coefficient Abel dashpot

Accurate description of creep behavior is of great significance to the safety evaluation of high-level radioactive waste disposal in granite. In this study, a fractional derivative constitutive model is proposed to depict the creep process of Beishan granite, based on the conformable derivative. A variable-coefficient Abel dashpot considering the effect of damage evolution on creep properties is introduced to describe the nonlinear dilatancy strain in the accelerating stage. A new model is proposed and further generalized to three-dimensional creep equations by adopting Drucker–Prager criterion, and the analytic solutions are given employing the Laplace transform. The parameters of new creep model are determined based on experimental data and fitting results are compared. The fitting curves present a good agreement with experimental data, indicating that the conformable derivative creep model achieves a good performance in describing all three creep stages. The proposed model is validated by the comparison of different experiments and degradation of fractional derivative model. In addition, a sensitivity analysis is carried out to show the effects of stress level, fractional derivative order, damage exponent, and other parameters.

Granitization and High-Temperature Metasomatism in Mafic Rocks: Comparison between Experimental Data and Natural Observations

The paper reports newly obtained data that append older results of experimental modeling of granitization processes. The experiments were aimed at modeling high-temperature metasomatism of mafic rocks, a process that involves the transfer of major components at 750°C and 500 MPa at a pressure gradient. The source of the transported Si, Ca, and Mg in the experiments was garnet. The solution was pure H2O and 25 wt % NaCl aqueous solution. In the experiments, garnet was decomposed into pyroxenes, amphiboles, plagioclase, and minor amounts of melt, ilmenite, and iron oxides. The associated partial dissolution led to the transfer and redeposition of the dissolved components on the surface of a gabbroanorthosite underlay and to the development of mineral rims, which were analogous to those produced at garnet decomposition. The compositions of the newly formed minerals in the rims were identical to those produced at metamorphism of gabbroanorthosite at Т ≥ 750°C, P > 700 MPa. When the mineral rim was formed, some elements are removed, and this process was controlled by the composition of the fluid phase. The pure H2O fluid removed Fe, Ca, and Mg. The aqueous fluid containing NaCl (XNaCl ≈ 0.1) did not extract Ca from minerals. This indicates that no high NaCl concentrations are typical of fluid in processes that form basificates at granitization. The experiments have shown that H2O and H2O–NaCl fluids remove more Fe that other elements. Preferable Fe extraction from naturally occurring associations is evident from the elevated Fe mole fractions of the mafic minerals and from the fact that the basificates typically contain magnetite and hematite.

Flexible Tools with Diamond Blades for Polishing Granite Surfaces

Polishing is an operation of treating the surface of the stone that gives it final useful features, giving the surface shine, which in the final stage of stone surface treatment give it important usable features, which include: aesthetics, i.e. surface property of the stone, characterized by the glassiness of the surface in some case has a mirror effect, which is characterized by a high degree of reflection of light, allowing it to observe the structure of the stone well in the aspect of its decorative elements placed on its surface. The physical features of polished surfaces are, above all, a shorter time to maintain moisture on its surface, which is the basic factor of material destruction. The quality of the polished surface of natural stone determines the degree of its longevity, this principle is particularly important for polished marble and concrete surfaces. An important value of the quality of polished products is the assessment of this parameter in a commercial assessment. The property of achieving a high degree of polishing can only be achieved with the help of highly effective diamond tools for polishing operations, where the quality of their work is evaluated by instrumental methods using tools measuring the amount of reflected light from the polished surface (gloss meter). Flexible diamond tools for dry and wet polishing operations are a set of 8 discs with a diameter of 100 mm mounted on a fast link formed in the friction surface on a synthetic binder of diamond abrasive with a grain size of 50 ÷ 3000 #. In order to increase the efficiency of surface treatment technology in polishing operations, it is necessary for granite processing for a given polishing operation with grain size 800 #, to select the appropriate hardness resulting from the synthetic binder formulation.

Behavior of RC Beam under Monotonic and Cyclic Loading using Waste Materials as Fine Aggregate

Crusher sand or Manufactured sand (M-Sand) obtained from stone aggregate quarries is widely used as fine aggregate in concrete to avoid the depletion of natural river sand. To avoid air and land pollution due to direct dumping of wastes in open land area from granite processing industries and thermal power stations, the behavior of reinforced concrete beam without waste (RC beam) and with waste (RCW beam) materials like granite powder (10%) and bottom ash (10%) as combined partial replacement for M-Sand was carried out. The parameters like load carrying capacity, ductility, energy absorption capacity and stiffness degradation were evaluated. The behavior of all the parameters of both the beams was similar and there was slight decrease (10%) in strength parameters due to increase in fine pore particles. Hence, the granite powder and bottom ash can be used as partial replacement for fine aggregate in building constructions.

Granitization and high-temperature metasomatism in mafic rocks: comparison of experimental and natural data

The paper reports newly obtained data that append older results of experimental modeling of granitization processes. The experiments were aimed at modeling high-temperature metasomatism of mafic rocks, a process that involves the transfer of major components at 750°C and 500 MPa at a pressure gradient. The source of the transported Si, Ca, and Mg in the experiments was garnet. The solution was pure H2O and 25 wt % NaCl aqueous solution. In the experiments, garnet was decomposed into pyroxenes, amphiboles, plagioclase, and minor amounts of melt, ilmenite, and iron oxides. The associated partial dissolution led to the transfer and redeposition of the dissolved components on the surface of a gabbroanorthosite underlay and to the development of mineral rims, which were analogous to those produced at garnet decomposition. The compositions of the newly formed minerals in the rims were identical to those produced at metamorphism of gabbroanorthosite at Т ≥ 750°C, P > 700 MPa. When the mineral rim was formed, some elements are removed, and this process was controlled by the composition of the fluid phase. The pure H2O fluid removed Fe, Ca, and Mg. The aqueous fluid containing NaCl (XNaCl ≈ 0.1) did not extract Ca from minerals. This indicates that no high NaCl concentrations are typical of fluid in processes that form basificates at granitization. The experiments have shown that H2O and H2O-NaCl fluids remove more Fe that other elements. Preferable Fe extraction from naturally occurring associations is evident from the elevated Fe mole fractions of the mafic minerals and from the fact that the basificates typically contain magnetite and hematite.

Oxalic Acid and Succinic Acid Mediate the Weathering Process of Granite in the Cold-Temperate Forest Regions of Northeast China

Granite is an important soil-forming rock and is widely distributed in the cold-temperate forest area of northeast China, such as northern Greater Hinggan, where its biochemical weathering plays an important role in the formation of local soils. Due to the special latitude and elevation, lichen plays a crucial role in the biochemical weathering of granite here, of which the role of low molecular organic acids (short for organic acids) is of interest. We simulated the concentrations of oxalic acid (OA) and succinic acid (SA) in the local lichens of Northeast China, applied OA or SA (10, 20, 30, 40, and 50 mmol L–1) to granite powders for 1 (10 min), 10, 20, 30, 40, 50, or 60 days, and studied the effects of organic acids on the bio-weathering process of granite, such as the dissolution regularity of various ions and the morphological changes of rock surfaces. OA and SA both induced the weathering and dissolving of granite, significantly promoted the release of Na+, K+, Al3+, Fe3+, Mg2+, Mn2+, Ca2+, and $${\text{SiO}}_{3}^{{2 - }}$$ from granite powders. For the ion dissolution, the effect of OA was stronger than that of SA. Infrared analysis showed that both organic acids did not change the structures of their own groups, and the weathering mechanism was mainly the complexation of organic acids. The results of electron microscopy also presented the dissolution of granite powders by organic acids, and the effects were enhanced as the treatment time increased. After organic acid applications, the concentrations of dissolved ions from the granite powder varied with the type and concentration of organic acids, and treatment time. The concentration of each ion usually reached its maximum at 50 or 40 mmol L–1 OA, and 50 mmol L–1 SA (except for Fe3+ of some treatments). At day 1, the concentrations of $${\text{SiO}}_{3}^{{2 - }}$$ , Al3+, Fe3+, and Mn2+ treated with OA were higher than those of other times. Compared with SA, OA could dissolve more ions from granite powders, especially at day 1. However, the metal ions dissolved by OA were easy to complex with OA, so the concentrations of ions treated by SA were higher than those of OA, and the ions dissolved by OA would enter into the soils more frequently in OA–metal complexes.

Experimental investigation of progressive cracking processes in granite under uniaxial loading using digital imaging and AE techniques

For a full understanding of the cracking processes in granite, uniaxial compression tests are conducted on prismatic specimens with pre-existing flaws, and digital imaging and AE techniques are applied to monitor real-time rupture behaviors. The digital image correlation (DIC) method is used to detect the process zone nucleation characteristics in granite. A novel approach for representing AE data in terms of the inter-event time (IET) function F(τ) is employed to analyze fracture-related AE event rate characteristics. Based on the coupled analyses of the acousto-optic-mechanical characteristics, the complete cracking processes of granite are classified into six levels, which are distinguishable by five characteristic stresses. Process zone nucleation, which represents the clustering of micro-cracks, is incorporated into the classification for the first time. Process zone nucleation is visualized as a white patch and is either linear or diffuse. By DIC analysis, the maximum principal strain field reliably predicts a linear white patch, and the maximum shear strain field implies a diffuse white patch. The evolutionary rules of the IET function F(τ) strongly support the new classification of cracking levels in granite. For the identification of stress thresholds and cracking levels, a combined acousto-optic-mechanical methodology is established, in which the role of the IET function F(τ) is highlighted.

Fracturing evolution analysis of Beishan granite under true triaxial compression based on acoustic emission and strain energy

The study of rock fracturing is a fundamental research topic in rock mechanics and engineering. In this paper, based on complete stress–strain curves obtained under TTC and the corresponding AE and strain energy results, the mechanical properties and fracturing process of Beishan granite are studied. A representative test result (σ2 = 75 MPa, σ3 = 20 MPa) is selected to analyse and illustrate the three-dimensional fracturing process of the Beishan granite. The results show that the variations in the characteristics of the brittle fracture behaviour, AE and strain energy of Beishan granite change with σ2 or σ3 following certain relationships, and the mechanisms driving these various relationships are very different. The AE and strain energy characteristics of Beishan granite are also quite different among the five fracturing evolution stages. The variations in the increments of AE count, AE event and total elastic strain energy per unit time (ΔSc/Δt, ΔSe/Δt and ΔUe/Δt) are studied at different times and under different stresses during rock failure. The rock fracturing evolution can be illustrated through the variation in these parameters, providing deep insight. This research provides a perspective for studying deep underground fracture-forming processes, such as earthquakes, tunnel sudden failure, spalling, splitting and rockburst.

Novel grain-based model for simulation of brittle failure of Alxa porphyritic granite

A grain-based model (GBM) is generally employed by many researchers to simulate the microcracking process of crystalline brittle rock by the distinct element method. In this study, a novel grain-based model (nGBM) in two-dimensional Particle Flow Code 5.0 (PFC2D 5.0) is proposed to emulate the brittle failure of crystalline rock. First, the nGBM scheme is introduced, in which the flat-joint model is employed to model the contacts in mineral grains and the smooth-joint model is assigned to the grain interface contacts. Then, compressive tests are performed using Alxa porphyritic granite, and the strength values are fitted with the Hoek-Brown failure criterion. Third, a nGBM was generated based on the petrographic texture of realistic rock, such as mineral constituents, grain size, and distribution. The input microscale parameters are carefully calibrated according the experimental results. Finally, this model is applied to study the microcracking process of Alxa porphyritic granite and the influence of spatial distribution of minerals. It is found that a relatively high ratio of uniaxial compressive strength to tensile strength of each mineral or synthetic samples can be reproduced by the nGBM. Moreover, the simulated results show this model can capture the nonlinear characteristic of the Hoek-Brown failure criterion. After modeling, numerous mineral grains were cut across, which is consistent with the actual experimental observation; the tensile crack is over the shear crack in the models, while the number of intra-grain shear crack increases dramatically with increasing confining pressure. In addition, the numerical results indicate that the effect of spatial distribution of minerals has limited influence on the evolution of microcracks but has great impact on microcrack distribution. In summary, the proposed nGBM in PFC2D can well reproduce the realistic failure process of granitic rocks under different loading conditions.

Computational and Experimental Analysis of Ultrafine Particle Dispersion During Granite Polishing

The granite manufacturing industry is an environment in which workers are exposed to high levels of ultrafine particles (UFPs) and crystalline silica dust. Overexposure to crystalline silica can cause health problems, in particular silicosis. This fatal lung disease persists worldwide despite knowledge of methods to control it. One way to partially overcome the problem of subjectivity and try to achieve objective experimental results is to run field crystalline silica dust surveys with trained human assessors (panelists). Such field inspections allow the determination of ambient air concentrations and are now seen as being a more convenient method for UFP impact assessment in the field. One drawback of field inspections is that they can get rather expensive, especially if the survey is conducted for an extended period of time involving a high number of panelists. This paper reviews the techniques that can be adopted to measure UFPs in the field and discusses how such techniques can be used as an alternative to, or in combination with, gas tracer dispersion methods for UFP impact assessment purposes, and how the results of field UFP measurements and model outputs can be related and compared to each other. Two simulation methods were used to study crystalline silica dust exposure during the granite polishing process (experimental and numerical). This study presents a method to measure UFP dispersion during granite manufacturing processes. A computational model was constructed to simulate the physical problem. The numerical study was carried out, on a simplified configuration (bench), modeling particle distribution near a rotating tool. CFD simulation results were compared to the experimental data using NaCl particles, a tracer gas (CO2), and UFP dispersion from granite polishing. The results showed good agreement between the two methods.