Silica Sand Research Articles

Analysis of cement raw material control using the min-max stock method in the PT semen bosowa maros

Inventory of raw materials is one of the crucial problems in the company. Errors in determining the size of raw material inventory is very influential for the smooth production of the company. PT Semen Bosowa Maros is a private company that focuses on cement production. This study aims to avoid excess and shortage of raw materials by calculating the amount of raw material inventory at PT Semen Bosowa Maros. This study uses the Min-Max Stock method. The research data was obtained from the company's annual data with related parties. The results of the study obtained safety stock values of Silica Sand 166.46 ton’s, Gypsum 1482.96 ton’s, Fly Ash 33.71 ton’s, and Trass 30.76 ton’s. Then, the minimum inventory calculation is carried out, it is known that the minimum inventory results are found in Trass raw materials of 260.18 ton’s while the results for maximum inventory are in Gypsum of 22117.18 ton’s. After calculating the min-max, an order policy can be obtained for each material, Silica Sand 1074.85 ton’s, Gypsum 9575.63 ton’s, Fly Ash 217.68 ton’s, and Trass 198.65 ton’s.

Material point method simulations of displacement pile and CPT penetration in sand considering the effects of grain breakage

Full displacement installation dramatically alters the stress and strain fields applying around piles and Cone Penetrometer (CPT) probes at sand sites. Calibration chamber tests have indicated that severe particle crushing occurs near to the pile or cone tips and a distinct shear zone may develop that leaves crushed sand adhering to the pile or cone shaft. It is therefore important to investigate how particle breakage affects the stress and deformation fields developed as this process occurs. In this study, installation by monotonic jacking of conically tipped model piles or CPT probes into silica sand is simulated by material point method (MPM) analyses. A thermodynamically consistent model which considers competing grain crushing and dilation is employed to model the sand behavior, while an MPM approach is adopted to cater for the large deformations involved in the penetration process. Particle crushing is predicted beneath the pile tip and around the pile shaft. The numerical results are compared to directly related instrumented pile calibration chamber tests. The numerical results show that the computed stress and displacement fields match key aspects of the experimental results well, especially in reproducing the volumetric compression observed experimentally. The results confirm that combining MPM with suitably sophisticated constitutive models creates new capabilities for analyzing large-deformation problems.

ANALIZE DIE CASTING PROCESS AND STRUCTURE OF MOLDING FOR INTERNAL COMBUSTION ENGINE VEHICLE

Die casting is part of manufacturing process for making metal product, especially internal combustion engine of vehicle. Molding is component for making product from metallurgy process or polymer process. Basically, all part of molding process will be using 3 conditions of process. First is solid raw material for process production, second is melting process of raw material for making product using molding and third is solid for part of finish product after process molding process. In this research will analyze of molding process and structure of engine for internal combustion engine vehicle. Mold casting will be using specification for SUV capacity 2.7L. basic raw material is silica sand, resin, bentonite, and sea coal. The result show that after process mixing optimal pressure from machine to molding is 109675,8 N. and spot test check result show that, after process die casting no any crack founding by 10 specimens of engine of vehicle.

Models of supply chain management in the efforts to develop the banyumasan batik industry

Inventory of raw materials is one of the crucial problems in the company. Errors in determining the size of raw material inventory is very influential for the smooth production of the company. PT Semen Bosowa Maros is a private company that focuses on cement production. This study aims to avoid excess and shortage of raw materials by calculating the amount of raw material inventory at PT Semen Bosowa Maros. This study uses the Min-Max Stock method. The research data was obtained from the company's annual data with related parties. The results of the study obtained safety stock values of Silica Sand 166.46 ton’s, Gypsum 1482.96 ton’s, Fly Ash 33.71 ton’s, and Trass 30.76 ton’s. Then, the minimum inventory calculation is carried out, it is known that the minimum inventory results are found in Trass raw materials of 260.18 ton’s while the results for maximum inventory are in Gypsum of 22117.18 ton’s. After calculating the min-max, an order policy can be obtained for each material, Silica Sand 1074.85 ton’s, Gypsum 9575.63 ton’s, Fly Ash 217.68 ton’s, and Trass 198.65 ton’s.

Recent advances in the marketing, impurity characterization and purification of quartz

Due to its stable physical and chemical properties and its abundance in nature, quartz is widely employed in industrial and high-tech applications. However, the presence of diverse types and states of impurities in quartz ores from different geological formations poses a challenge in the process of purifying high-purity quartz, leading to wastage of raw materials and escalated costs. This study presents the socio-economic applications of quartz, scrutinizes the formation and separation mechanisms of impurities in quartz ores from a mineralogical perspective, examines the obstacles faced in quartz purification, explains the current state of development, and provides a technical summary of quartz purification. The analysis reveals that lattice impurity elements and various types of inclusion impurities are the principal factors affecting the purity of quartz. Various green separation techniques are applied based on the composition of the quartz minerals and the state of the impurities. Standard practices may involve physical pre-treatment such as scrubbing, ultrasonic crushing, and electromagnetic pulse cracking, followed by rough cleaning through color separation, superconducting high gradient magnetic separation, and flotation, and chemical pre-treatment (high-temperature or microwave roasting with chloride doping, and ammonium sulfate thermal crushing combined with water quenching to remove gas-liquid inclusions from quartz minerals). Finally, finishing processes such as fluorine-free and catalytic hot-pressure acid leaching or microbiological purification treatment with filamentous or Aspergillus fungi are used to obtain high-purity silica sand with an anticipated purity of about 99.99%.

Layanan Pengolahan Air Limbah Binatu bagi Usaha Mikro, Kecil, dan Menengah dengan Teknik Filter Karbon Aktif

Laundry activities utilizing detergents as cleaning agents generate non-degradable waste, posing environmental and health hazards. Laundry services, or laundries, have experienced rapid growth in Jayapura City, resulting in substantial laundry waste discharge directly into the environment. Activated carbon, with its porous and highly absorptive nature, proves effective to absorb waste particles. This community engagement initiative focuses on providing education and implementing small to medium-scale laundry waste treatment for micro, small, and medium-sized enterprises. The project collaborates with Zifara Laundry, a laundry business located in Waena, Heram District, Jayapura City. The partner receives essential education on the importance of pre-treating laundry waste before disposal into the environment. The engagement team installs waste filters based on activated carbon, augmented with silica sand, gravel, and cotton filters in each layer. As a result, both the business owner and laundry workers gain a profound understanding of the significance of treating laundry waste before environmental discharge. The waste filters installed by the engagement team on the central laundry waste disposal channel contribute to an improvement in laundry wastewater quality. Turbidity levels decrease from a scale of 150-200 NTU to 1-2 NTU after the installation of activated carbon-based laundry waste filters.

Experimental study on the mechanical behavior and energy absorption capacity of coral sand at high strain rates

This study investigated and compared the compression responses and energy absorption capacities of coral sand and silica sand at a strain rate of approximately 1000 s−1. To this end, the effects of the relative density and particle size distribution on the abovementioned properties were analyzed, and the stress–strain curves, yield stresses, compressibilities, energy absorption curves, and energy absorption ratios were obtained. The experimental results showed that coral sand had a significantly higher energy absorption capacity than silica sand owing to its higher compressibility. The energy absorption curve for sand was primarily influenced by the yield stress and energy absorption ratio. The lower relative density of coral sand contributed to its higher compressibility and energy absorption capacity compared to silica sand. For coral and silica sands with different particle sizes, the intersection of the stress–strain and energy absorption curves was observed and analyzed. Formulas for predicting the yield stress, compressibility, and energy absorption curve of coral sand were derived, considering the variations in the relative density and particle size. The study findings reveal that using poorly graded coral sand with large particle sizes can improve the energy absorption capacity of coral sand.

Nutrients and phytochemical density in Mesembryanthemum crystallinum L. cultivated in growing media supplemented with dosages of nitrogen fertilizer

Mesembryanthemum crystallinum L. is an annual halophyte that originated from southern Africa. However, little has been reported about factors that modulate the quantity of secondary metabolites in the plant. In this study, the twin effect of different nitrogen concentrations (0.36, 0.6, 0.8 g/L) and growing media (LECA clay, peat, vermiculite and silica sand) on plant growth, chlorophyll contents, minerals, proximate and antioxidant metabolites in hydroponically cultivated M. crystallinum was investigated. This is important to determine the dosage of N fertilizer that will optimize the bio-productivity and biosynthesis of secondary metabolites and antioxidants in M. crystallinum grown in a hydroponic system. The untreated plant (0 g/L N) was taken as the control. At the end of the experiment, optimum yields in leaf number (9.2), fresh weight (50.40 g), Ca, N, and Protein (34.04 %) were recorded in M. crystallinum grown with peat enhanced with different dosages of N-fertilizer. Likewise, chlorophyll level, dry weight, ABTS/TEAC, FRAP, ADF and NDF contents were optimized in LECA clay treated with N-fertilizer. Silica sand with 0.36 g/L dosage of nitrogen fertilizer optimized P, Mn and Zn levels, so also the moisture (9.83 % at 0.8 g/L N), fat (2.38 %, 0 g/L N) and carbohydrates (44.98 and 44.95 %). The highest ash content, Mg and Fe were recorded in the untreated vermiculite as well as polyphenols and K, at 0.6 g/L; Cu and root length (14.60 cm), at 0.8 g/L. In conclusion, different dosages of nitrogen fertilizer and growing media could enhance the growth potential, chlorophyll, phytochemicals, and nutritional properties of M. crystallinum.

Wettability, flowability and core bending strength of wet silica sand particles based on the interfacial properties of liquid silicate binders

The flowability of wet silica sand particles containing liquid binders, which are among the new moulding materials for green casting, must be further improved. Herein, we conducted an in-depth study on the interface characteristics of silicate binders with the addition of anionic surfactants. Through particle flow experiments and sand core bending fracture experiments, the influence of anionic surfactants on the flow characteristics of wet sand particles and the mechanical properties of silicate-bonded sand was explored. The experimental results showed that the addition of 0.10 wt% of an anionic surfactant significantly reduced the surface tension and contact angle of solutions, from 78.99 to 28.53 mN/m, and from 49.9° to 34.4°. Moreover, compared with unmodified wet particles, the flowability of wet particles modified with 0.10 wt% of the anionic surfactant was improved to some extent. However, the flexural strength of silicate-bonded sand was also reduced to a certain extent.

Calcium silicate biocomposites: effects of selenium oxide on the physico-mechanical features and their in-vitro biological assessments

Bone tissue regenerative material serves as a prospective recovery candidate with self-adaptable biological properties of bio-activation, degradability, compatibility, and antimicrobial efficacy instead of metallic implants. Such materials are highly expensive due to chemical reagents and complex synthesis procedures, making them unaffordable for patients with financial constraints. This research produced an efficient bone tissue regenerative material using inexpensive naturally occurring source materials, including silica sand and limestone. The extracted SiO2 and CaO particles (75:25 wt%) were subjected to hydrothermal synthesis (water treatment instead of chemical solvents) to produce the CaSiO3 biomaterial (code: S). Selenium oxide was doped with calcium silicate at 3, 5, and 10 wt.% to enhance its properties, yielding biocomposite materials (i.e. S3, S5, and S10). The physico-mechanical properties of these materials were investigated with x-ray diffraction, Fourier transform infrared, FESEM-EDS, and micro-universal testing machine. The results revealed that the synthesized biocomposites have a crystalline wollastonite phase with a porously fused rough surface. From structural parametric calculations, we found that the biocomposites have reduced particle size and enhanced surface area due to the influence of selenium oxide. The biocomposite S10, having high SeO2 content, attained the maximum compressive strength of 75.2 MPa. In-vitro studies of bioactivity, biodegradability, biocompatibility, and antibacterial activity were performed. At 7 and 14 d of bioactivity, the synthesized biocomposites are capable of dissolving their ions into simulated body fluid (SBF) solution to precipitate hydroxyapatite and a required Ca/P ratio of 1.69 was achieved by S3. A comparative analysis has been performed on the degradation activity in Tris-HCl and the consequent pH changes during SBF treatment. The bio-analysis revealed that the biocomposite S3 shows enhanced bioactivity through a controlled degradation rate and secured cell viability of 88% at a concentration of 100 μg ml−1. It also offers significant bacterial inhibition potency against E.coli and S.aureus bacteria.

Blast Furnace Slag as an Alternative to Silica Sand for A356 Alloy Casting-Feasibility Study

Blast Furnace Slag as an Alternative to Silica Sand for A356 Alloy Casting-Feasibility Study

Optimizing material selection: A study of erosion-corrosion performance in homogeneous and carbide-containing materials

Erosion-corrosion is a major factor contributing to material loss and reduced useful life of hydro-transport equipment. The combined effect of erosion and corrosion is responsible for high degradation rates. In oil sand mining, materials from different classes are used for various applications depending on the severity of degradation. In this research, we assessed the erosion-corrosion characteristics of four uniform materials (pipeline and abrasion-resistant steels) as well as five materials containing varying types and quantities of carbide (chrome white iron and WC-based overlay). The materials underwent erosion-corrosion testing within a slurry container (comprising 3.5 wt% NaCl + 35 wt% natural silica sand) at a temperature of 45 °C. Under the test conditions, it was found that matrix wear influences the extent of carbide degradation for all carbide-containing materials. To provide good erosion-corrosion resistance, the surrounding matrix that supports the carbide must have sufficient wear and corrosion resistance. This study also identifies the dominant wear mechanisms for both uniform and carbide-containing materials.

EXPERIMENTAL AND NUMERICAL STUDY ON THE BEHAVIOUR OF SILICA SAND SLOPE MODEL SUBJECTED TO SURCHARGE LOAD

Natural disasters such as landslides are becoming more frequent due to global warming. Because of the more frequent occurrences of natural disasters, there is an urgent need for researchers in geotechnical engineering to conduct slope stability analysis. This paper presents the findings of a laboratory experiment and numerical analysis of the behaviour of silica sand under static loading conditions. The laboratory experiment modelled a small-scale slope in a 500mm wide, 1000mm high and 1500mm long acrylic box. The numerical modelling in the experiment employed, Finite Element Modelling (FEM), Plaxis 3D, and the Hardening Soil Model (HSM). The researchers conducted a consolidated-drained (CD) triaxial compression test to determine the parameters of the silica sand. The FEM results are similar to the test results for the maximum loading conditions of 9.6kN/m2. The experimental observation revealed that applying a surcharge load on the top of the slope surface resulted in deformation and bulging. These observations were consistent with and validated the experimental and numerical results. The results of this study will be used to investigate the application of a proposed prototype inclinometer sensor for slope monitoring technology.

Analysis of the Influence of PET and Glass Packaging Waste Materials on the Physical and Mechanical Properties of Cementitious Composites

The limited availability of natural resources, such as sand, and the need to reduce CO2 emissions, which are produced in large quantities in the production of binding materials, indicate the need to look for alternative raw materials used in construction materials. At the same time, there is a strong need to utilise waste packaging materials, the global production of which is constantly increasing. This work aims to investigate the possibility of using recycled polyethylene terephthalate (PET), utilised as a partial substitute for fine aggregate, and waste glass, implemented as powder, serving as a partial substitute for cement in the manufacturing of the cementitious composites. An experimental study was carried out to evaluate the physical and mechanical properties of the resultant cementitious composites. The incorporated PET aggregate comprised 0%, 5%, and 10% by volume of silica sand and 0%, 10%, and 20% glass powder by weight of cement. The addition of waste raw materials augmented the flow of fresh mortars, predominantly subsequent to the introduction of PET recyclate. The deployment of artificial aggregate in mortars induces a decrease in the volumetric density. Concurrently, the mechanical properties of mortars enriched with waste materials exhibited a reduction, in terms of both compressive and flexural strength, with the detriment escalating in conjunction with the content of waste raw materials. An analysis of statistical significance of effects, grounded in an analysis of variance, is delineated within this document, pinpointing the quantities of waste raw materials that can be assimilated in mortars without inducing a substantial deterioration of strength properties. Through studies on phase composition, it has been demonstrated that the utilised glass waste, possessing a grain size analogous to cement, exhibited poor pozzolanic properties. The test results indicate that it is possible to partially replace cement with glass powder, up to 10%, and fine aggregate with PET waste, up to 5%, without a significant reduction in the mechanical properties of the material.

Turbidity Reduction by Using Variations of Filtration Media Sizes (Case Study of Treated Water PT. X Jakarta)

Turbidity is one of the main water quality parameters in drinking water quality. One way to reduce turbidity levels is by filtration. The filtration unit in the water treatment plant must use appropriate media so that the processed raw water meets World Health Organization (WHO) standards. WHO states that the turbidity of processed water before disinfection is 1 NTU. This research was conducted to know the efficiency of filtration processing with various media in reducing the concentration of turbidity in raw water. This study used three types of media, namely 50% silica sand with a mesh size of 12-16 and 50% silica sand with a mesh size of 8-12 (C), 100% silica sand with a mesh size of 12-16 (K), and 100% silica sand in mesh size. 8-12 (B). Porosity value for each sample C, K, and B is 0.412; 0.423; and 0.388. The detention time at maximum discharge for samples C, K, and B was 3.6, respectively; 3.76; and 3.45 minutes. The flow rates used for media samples C, K, and B were 4125 L/s and 2500 L/s, respectively. The removal efficiency produced by the highest turbidity was obtained in medium C with values of 90.8% and 89.9%, respectively. Meanwhile, media B gave the lowest turbidity removal efficiency, namely 86.3% and 86.4%. The results of all variations of the media used have met WHO standards, where the processed results have produced turbidity concentrations of 0.25 - 0.32 NTU.

Wettability, adhesive performance and structural evolution of an environment-friendly modified silicate binder for foundry moulding and coremaking

For the manufacturing of sand cores, silicate inorganic binders have emerged as promising green casting binder materials; however, their adhesive performance requires further improvement. In this study, to evaluate the impact of using water-soluble polyols, i.e. polyethylene glycol (PEG) and xylitol, to modify silicate adhesives, the effect of the content and type of water-soluble polyol on the colloidal stability, wettability and adhesive performance of a silicate binder were investigated. The structural evolution of the modified silicate binder and the polysilicate bondswere studied using characterisation techniques including infrared spectroscopy and 29Si nuclear magnetic resonance (NMR) spectroscopy. Results revealed that PEG 400 and PEG 600 increased the size of polysilicate particles in the solution, resulting in flocculation of the silicate binders and easy precipitation or separation in a short period of time. However, PEG 200 and xylitol exerted little effect on the stability of the silicate solution. Moreover, 0.25 wt% PEG 200 reduced the surface tension of the solution from 78.93 to 54.15 mN/m and the equilibrium contact angle from 45.0° to 34.6°. The polyol promoted the dehydration and condensation of silicic acid gel to form a more stable three-dimensional network structure, improving the bonding strength of casting sand cores prepared using the silicate binder and silica sand from 2.42 to 3.02 MPa. This study not only unveils the role of PEG in improving the wettability and bonding behaviour but also provides an example of the rational use of environment-friendly water-soluble polyols to enhance the performance of green inorganic adhesive materials.

Shrinkage, Permeation and Freeze-Thaw Characteristics of Ambient Cured High Calcium-Based Alkali-Activated Engineered Composites.

Sustainable zero cement-based one-part ambient cured alkali-activated engineered composites (AAECs) are developed. The durability and microstructural characteristics of developed AAECs using 2% v/v polyvinyl alcohol (PVA) fibers, silica sand, binary or ternary combinations of precursors (fly ash class C 'FA-C', fly ash class F 'FA-F' and ground granulated blast furnace slag 'GGBFS') and two types of powder form alkaline reagents (Type 1 and Type 2) are evaluated compared to conventional engineered cementitious composites (ECCs) and alkali-activated mortars (AAMs) without fiber. AAECs developed satisfactory compressive strength ranging from 34 MPa to 46 MPa. Expansion/shrinkage and mass change (loss/gain) behaviors are affected by binary/ternary combination of source materials, reagent types and curing regimes (water or ambient) for both AAMs and AAECs. The binary (FA-C + GGBFS) and reagent 2 (calcium hydroxide + sodium sulfate) composites demonstrated lower shrinkage due to formation of crystalline C-A-S-H/C-S-H binding phases than their ternary (FA-C + FA-F + GGBFS) and reagent 1 (calcium hydroxide + sodium metasilicate) counterparts which formed amorphous N-C-A-S-H/N-A-S-H phases. The matrix densification due to the formation of reaction products and fiber-induced micro-confinement leads to lower shrinkage and mass change of AAECs compared to their AAM counterparts. Composites exhibited lower or comparable secondary sorptivity indices compared to control ECC, indicating their superior permeation performance. All AAECs had a relative dynamic modulus of elasticity (RDME) greater than 90% at 300 cycles (comparable to control ECC), exhibiting satisfactory freeze-thaw resistance with reagent 2 mixes showing better performance compared to those with reagent 1. The production feasibility of strain hardening AAECs with powder form reagents having satisfactory mechanical and durability properties is confirmed.

The Effect of Surface Roughness of Inconel 738 Superalloy on the Adhesive Properties of 8YSZ Coatings Deposited by Electrophoretic Deposition (EPD)

The electrophoretic deposition coating method has recently received attention as a new method for thermal barrier coating due to its advantages such as the simplicity of the method, controllability of the process, and the need for simple equipment. In this study 8 wt % yttria- stabilized zirconia was deposited on Inconel 738 substrate at room temperature by electrophoretic deposition. Before deposition, the substrates were treated by sand blasting treatment (by silica sands with different sizes) and roughness in the range of Ra=1 and Ra=3 was achieved on the substrate surfaces. The coated samples were sintered at 1100 °C temperature under controlled atmosphere (Ar atmosphere). X-Ray diffraction, scanning electron microscopy and thermal shock resistance technics were used to investigating of structural and phase properties and adhesiveness between coatings and substrates. Results from thermal shock resistance test show that by increasing roughness number, the thermal shock resistance ability first increased and then decreased. In addition, according to SEM images, increasing of roughness number, causes decrease the microcracks that creating in the coating surface. The best result was observed for coatings deposed on substrate with Ra=2.

Alkali-based components as slag fluidizers in steelmaking processes: A thermodynamic assessment

Defining the optimized volume of dual saturated (CaO and MgO) slags is of utmost importance to secondary metallurgy, especially for the ladle furnace. To be effective, these slags may present high desulphurization capability, combining the ability to shield the electric arc flare, to avoid the skull formation in the ladle borders and bottom, and suitable viscosity to provide fast incorporation of additives and tapping. Some fluidizers are applied for attaining the purpose of taking CaO/MgO into solution, being fluorspar (calcium fluoride, CaF2) and silica sand (silicon oxide, SiO2) broadly used in Si-killed steelmaking plants. At the Al-killed plants, either bauxite (mainly aluminum hydroxide) or calcium-aluminates are recommended choices. Nevertheless, for various reasons, some steelmakers use alternative fluidizers containing a significant amount of Na2O and K2O, such as sodalite and nepheline. Based on thermodynamic calculations (CALPHAD method), the effects of such alkalis on the CaO/MgO solubility and the optical basicity of slags on the CaO–SiO2–MgO–Al2O3 system were explored in this paper. Moreover, the potential impact on the performance of MgO-based refractories in contact with these alkali-containing slags was also assessed by a thermodynamic approach. Although kinetic aspects must also be considered, it was seen that (Na2O)2·(K2O) additions into these systems must be carefully managed to make the most of their ability to improve desulphurization, while avoiding the earlier corrosion of the refractory lining.

Effect of Carbon Dioxide Temperature on Adhesion of Na2SiO3 Binder to Silica Sand Surface: Comparison of Experimental Data with Molecular Dynamics Simulations

Effect of Carbon Dioxide Temperature on Adhesion of Na2SiO3 Binder to Silica Sand Surface: Comparison of Experimental Data with Molecular Dynamics Simulations