Rheology-driven approaches in slurry transportation: Influence of bimodal mixtures, additives, and modelling perspectives.

Flow resistance is a critical determinant of the efficiency and economics of a slurry pipeline. This study aims to reduce pipeline resistance by integrating a swirler to enhance particle suspension. The variation laws of slurry conveying resistance with and without a swirler under various conveying conditions were investigated. Whether a swirler is present or not, the conveying resistance increases with an increase in the conveying velocity (1~6 m/s), volume concentration (10~50%), particle diameter (0.1~5 mm), particle density (1100~1500 kg/m3), and pipe inclination (0~90°). It decreases with an increase in the pipe diameter (50~200 mm). A moderate swirling intensity reduces the resistance in high-velocity large-particle slurry transport. Considering the swirling flow characteristics in the conveying pipeline, resistance loss calculation models accounting for these characteristics were established for different flow states of the slurry in the pipeline. Taking into account the swirling characteristics in the conveying pipeline, a calculation model for resistance loss of the slurry in different flow states within the pipeline was established. The average error between this model and the experimental results was 9.04%.

Slurry pipeline transportation of iron ore is recognized as a reliable and cost-effective method for long-distance mineral transport. Understanding the associated energy costs is crucial for predicting energy demand and optimizing operational control. This study analyzes the energy consumption of Samarco S.A.’s slurry pipeline 2 over a 16-month period (January 2021 to April 2022), covering 473 operational days. A direct relationship was established between the dry metric tons (dmt) pumped and the total energy consumed (kWh) by the pumping stations. The results indicate an average consumption of 3.9 kWh per dmt, corresponding to an energy cost of R$ 2.27 per dmt, considering the average Brazilian electricity tariff. These findings provide a basis for more accurate energy demand planning and highlight scenarios where deviations in consumption may signal operational inefficiencies or equipment issues.

Investigation of deposition behavior in non-Newtonian oil-wax slurry pipeline transport based on experiment and CFD-CGDEM method

The pipeline conveying system as the gangue slurry filling technology lifeline. The occurrence of pipeline blockage will lead to the paralysis of the entire filling system; timely detection of pipeline blockage and early warning are needed to ensure the safe, stable, and efficient operation of the core elements of the coal gangue slurry filling system. Based on this, this paper summarizes and analyzes the classification of pipeline blockage and summarizes the current pipeline conveying blockage detection technologies. It elaborates in detail on the principles and advantages and disadvantages of existing pipeline blockage detection technologies, and points out that distributed optical fiber acoustic wave sensor (DAS), as an emerging fiber optic detection technology in recent years, can achieve high-precision, large-scale, real-time dynamic and distributed acoustic detection, Compared with traditional monitoring for pipeline blockage, it is more suitable for detecting blockage in coal gangue slurry pipeline conveying; then from the sensing principle of distributed fiber optic acoustic wave sensing technology, it discusses the current status of DAS technology application, analyzes the pipeline blockage DAS detection mechanism, and verifies the feasibility of pipeline conveying blockage detection based on the distributed fiber optic acoustic wave sensing technology by building a pipeline blockage DAS detection simulation experiment system; finally, it puts forward the feasibility of distributed fiber optic acoustic wave sensing technology; finally, it puts forward the feasibility of distributed fiber optic wave sensing technology detection. Finally, a pipeline blockage DAS detection and identification system is proposed, the function of each subsystem is introduced, and the core key technology involved in the pipeline blockage DAS detection and identification system is analyzed in detail, and the future development direction of gangue slurry pipeline conveying blockage DAS detection technology is also pointed out in order to provide reference for the development of the subsequent gangue slurry pipeline blockage and other pipeline conveying blockage DAS detection technology.

ABSTRACTOil pipeline transportation is the primary mode of transporting petroleum products, and its safety and environmental concerns have garnered significant attention. The decommissioning of oil and gas pipelines plays a crucial role in the life cycle management of these pipelines. Worldwide, addressing the aging issue of oil and gas pipelines has become an urgent matter that requires immediate resolution. In order to effectively abandon underground oil and gas pipelines while ensuring sustainable development, this study conducts numerical simulation analysis on Controlled Low Strength Material (CLSM) used for filling and decommissioning purposes. In this paper, CLSM slurry, a new material with low strength, high fluidity, and low bleeding rate, is regarded as Bingham fluid. The changes of initial yield stress and plastic viscosity of the slurry with time are studied by rheological equations, and the rheological equations of CLSM slurry are proposed. In this paper, the flow dynamics characteristics of CLSM slurry in a straight pipe are studied by numerical simulation, and the flow velocity field changes of slurry in a straight pipe at different time points, different flows, and different diameters are analyzed. Additionally, a numerical calculation model is established to simulate the flow dynamic characteristics of CLSM slurry pipelines, aiming to provide reliable theoretical and technical support for developing a comprehensive and efficient CLSM filling technique within the context of decommissioned oil and gas pipeline systems.

In this study, the rheological feature of bottom ash-water slurry was investigated by using NaCl as an additive. The additive was added into the bottom ash suspension with proportions of 0.2, 0.4, and 0.6% (by weight). The range of solid concentration in the suspension varied from 10 to 60 % (by weight). When compared to the normal condition or without additive, the addition of NaCl results in a very obvious reduction in the apparent viscosity of the solution. The addition of 0.4% additive shows good agreement with the reduction of energy consumption as compared to the rest of the range of velocities. Because of the reduction in energy consumption, the required pump power decreased up to a remarkable limit of approximately 20%. Sensitivity analysis demonstrates that increasing NaCl concentration reduces apparent viscosity, pressure drop, and specific energy consumption, leading to improved flow efficiency. According to the findings of the investigation, the suspension of bottom ash slurry described in the above manner has the potential to be transported in a slurry pipeline using the least amount of energy.

Currently, perfusing deceleration aggregate is the most effective way to create water-blocking sections for controlling coal mine water inrush disasters. Clarifying the two-phase coupling migration mechanism of deceleration aggregate and water in coal mine water inrush channels is the key to quantitatively determining the deposition and migration distance of aggregate after entering the water inrush channel from the perfusion hole. Based on fluid mechanics, slurry pipeline transportation theory and sediment dynamics, this paper categories the entire migration process of aggregate entering the water inrush channel from the perfusion hole into three motion stages: free fall, curved-throwing, and sliding. The motion and force characteristics of each stage are analyzed, and a theoretical model for single-aggregate sedimentary migration is established. The CFD-DEM method is used to establish a transient bidirectional coupling numerical calculation model of aggregate-water to verify the theoretical model (overall error not exceeding 10%). Finally, based on this research, reasonable suggestions are proposed for the actual engineering of plugging by perfusing deceleration aggregate.

The paper determines the parameters of slurry transportation systems that have a major impact on failure-free operation of hydraulic transport systems of mining enterprises in conditions of low temperatures. A regularity of hydraulic and thermal interaction of the structural elements of pump-operated hydraulic transport has been established for selection of operating modes for the slurry pipelines in conditions of negative temperatures. This regularity was used to develop an algorithm, in which the created automatic system to control parameters of the hydraulic system and the presence of a subsystem for modeling and predicting the internal processes that take place in the pipeline, makes it possible to arrange the transportation process, in which the correction of temperature parameters of the hydraulic system is based on internal forces of the system, but not on external factors. It is proposed to use the dependence of the specific friction heat on the values of the flow velocity, the pipeline diameter, the ratio of the liquid and solid phases, and the density of the slurry for conditions of pumping copper ore tailings with a constant volume concentration, in order to form a methodology that maintains an automatic operation mode of the hydraulic transport system for highly concentrated copper ore tailings.

Vibration and wear assessment of slurry TBM discharge pipeline transporting large sized rock particles: CFD-DEM-FEM multifield coupled simulation

Heuristic based decision approach for an integrated slurry pipeline network scheduling in the phosphate industry

Slurry transportation is an essential process in numerous industrial applications, widely studied for its efficiency in material conveyance. Despite substantial research, the impact of pipe wall roughness on critical metrics such as pressure drop, specific energy consumption (SEC), and the Nusselt number remains relatively underexplored. This study provides a detailed analysis using a three-dimensional computational model of a slurry pipeline, with a 0.0549 m diameter and 3.8 m length. The model employs an Eulerian multiphase approach coupled with the RNG k-ε turbulence model, assessing slurry concentrations Cw = 40–60% (by weight). Simulations were conducted at flow velocities Vm = 1–5 m/s, with pipe roughness (Rh) ranging between 10 and 50 µm. Computational findings indicate that both pressure drop and SEC increase proportionally with roughness height, Vm, and Cw. Interestingly, the Nusselt number appears unaffected by roughness height, although it rises corresponds to Vm, and Cw. These insights offer a deeper understanding of slurry pipeline dynamics, informing strategies to enhance operational efficiency and performance across various industrial contexts.

Slurry filling technology has been increasingly adopted in coal mines in the northwest region. However, due to the complexity of slurry transport pipelines, blockages remain a frequent issue. These blockages can reduce operational efficiency, with different blockage types causing varying levels of damage. Despite the significance of this issue, there is limited in-depth analysis in the literature, especially regarding the role of pressure in pipeline blockages. This study utilizes FLUENT 2020R2 (the fluid simulation software) for computational fluid dynamics simulations of slurry pipeline blockages, focusing on the impact of blockage morphology, location, and extent on slurry transport pressure distribution. The results indicate that the greater the blockage extent, the more pronounced the pressure loss along the pipeline. Furthermore, blockage morphology also has a varying effect on pressure drop. At lower blockage levels, the pressure drop variation across the three blockage types is relatively minor. However, when the blockage exceeds 50%, sedimentation-type blockages (B-blockage) cause the most significant harm. The study identifies the underlying causes of this and provides recommendations to mitigate sedimentation-type blockages. Within 1 m downstream of the blockage, the flow velocity rapidly decreases to near zero, creating a stagnant zone that accelerates the deposition of gangue particles, thereby worsening the blockage. After a sudden blockage, the location of the blockage has minimal impact on pressure drop. The influence on slurry pressure is ranked as follows: sedimentation-type blockage (B-blockage) > composite blockage (C-blockage) > attachment-type blockage (A-blockage).

The article aims to identify possible directions for developing heat technology systems in Irkutsk Oblast, taking into account the integration of resources of the Irkutsk coal basin with high sulfur content. The study applied a systems analysis of trends in the development of high-capacity coal-fired power boilers, considering the possibility of reducing harmful emissions (NOx, CO, SOx) primarily through rational design solutions and the use of coal-water slurry. It is shown that swirl processes realized in fuel combustion schemes that are applied at the TPPs of the Irkutsk power system help to improve the ecological and economic efficiency of heat technology systems, primarily by reducing the combustion temperature and increasing the residence time in the furnace. Experience is available in applying the low-temperature swirl combustion scheme at Ust-Ilimskaya TPP (boiler 6) and a circular furnace at Novo-Irkutskaya TPP (boiler No. 8). It is proposed to redesign the existing power boilers according to the scheme of low-temperature swirl combustion (i.e., the maximum temperature in the furnace is no higher than 1000–1100℃), with the subsequent use of partially demineralized and desulphurized coal-water slurry obtained at the place of extraction and transported by slurry pipeline. Fuel can be burned in a two-stage furnace: it is ignited in its lower part where the low-temperature fluidized bed of inert material is located; then, it is burned completely in the upper part of the furnace at a temperature of 1000–1200℃. Thus, in the context of the growing use of highsulfur coal, the evolution of technological systems in the thermal power industry of Irkutsk Oblast places its cleaning within the scope of activities of power companies. The main method of reducing the emissions of sulfur compounds consists in the low-temperature combustion of fuel using desulfurized coal water slurry.

Slurry transport via pipelines is a widely used method across various industries globally. While extensive research exists on optimizing parameters for efficient slurry pipeline systems, studies on the optimal combination of two mixtures to maximize efficiency in bi-modal slurry transport remain limited. This research addresses the gap by developing a three-dimensional computational model to examine the energy, transport, and thermal characteristics of mono-dispersed and bi-modal slurries. The model compares these characteristics with the behavior of pure water flowing through a straight pipe, providing insights into how slurry composition affects flow dynamics and heat transfer. The study investigates slurry flow through a round straight pipe at Reynolds numbers ranging from 128,035 to 320,000 and volumetric concentrations (Cvf = 10–40 %). The bi-modal slurry consists of silica sand and fly ash mixtures in proportions of 85:15 and 65:35, while the uni-modal slurry has proportions of 100:0 and 0:100. Computational results indicate that the 65:35 mixture, flowing at Re = 128035 and Cvf = 10–20 % achieves the lowest pressure drop and specific energy consumption (SEC), enhancing transport efficiency. Furthermore, wall shear stress (WSS) and energy consumption increase with higher Reynolds numbers and volumetric concentrations. Notably, the 100:0 mixture achieves the highest convective heat transfer coefficient, which increases with Reynolds number and volumetric concentration.

Slurry pipeline transportation is widely used in dredging and serves as an essential method for conveying solid materials. However, accurately describing the interaction between slurry and particles through numerical simulations, while optimizing the pipeline structure to improve the performance of slurry pipelines, poses a significant engineering challenge. In this study, a Z-shaped continuous pipeline, designed using B-spline curves, is implemented in the slurry circulation system. The validity of the CFD–DEM method is confirmed through slurry circulation experiments, and the effects of various structural parameters on transportation efficiency and flow characteristics are investigated. By integrating the Kriging surrogate model with the NSGA-II algorithm, a multi-objective optimization method is proposed to reduce computational complexity and improve the sediment-carrying capacity of the Z-shaped pipeline. Using a slurry shield tunneling machine with a diameter of 6.24 m as an example, this study optimizes a Z-shaped pipeline with an inner diameter of 0.3 m and an axial height of 1.5 m. The optimized structural parameters increase the average particle velocity by 8.9% and reduce particle accumulation by 21.3%. Additionally, the interaction between the pipeline’s inclination angle \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ heta$$\\end{document}, the B-spline control parameter \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$l_{4}$$\\end{document}, and the sediment-carrying capacity is analyzed.

Dynamic fluid flow model for phosphate slurry pipeline: OCP main pipeline as case study

Under the trend of carbon neutrality, the adoption of electric mineral transportation equipment is steadily increasing. Accurate monitoring of the operational status of electric check valves in diaphragm pumps is crucial for ensuring transportation safety. However, accurately identifying the operational characteristics of electric check valves under complex excitation and noisy environments remains challenging. This paper proposes a monitoring method for the status of electric check valves based on the integration of Adaptive Focal Loss (AFL) with residual networks and Extreme Learning Machines (AFL-ResNet-ELMs). Firstly, to address the issue of unclear feature representation in one-dimensional vibration signals, grayscale operations are employed to transform the one-dimensional data into grayscale images with more distinct features. Residual networks are then utilized to extract the state features of the check valve, with Extreme Learning Machines serving as the feature classifier. Secondly, to overcome the issue of imbalanced industrial data distribution, a new Adaptive Focal Loss function is designed. This function focuses the training process on difficult-to-classify data samples, balancing the recognition difficulty across different samples. Finally, experimental studies are conducted using industrially measured vibration data of the electric check valve. The results indicate that the proposed method achieves an average accuracy of 99.60% in identifying four health states of the check valve. This method provides a novel approach for the safety monitoring of slurry pipeline transportation processes.

In this paper, implementation of a comprehensive mechanistic model for the prediction of erosive wear in pipelines due to solid particles impact was investigated.The aim of this study is to develop a mechanistic model coupled with CFD model to predict the rate of inner-wall erosive wear of pipeline due to the presence of solid particles. This mechanistic model was developed based on Hertzian contact, and Du and Wang elastoplastic impact models; taking the deformation of the erodent particles and the effective impact angle into consideration. The developed models were compared with experimental data from three different sources and with built-in erosion models in FLUENT. The outcome of the simulation show that the developed model is 92% accurate when compared with the experimental values. Themechanistic model of this study shows a good agreement with the existing models. The trend of variation of erosive wear rate with impact angle, particle velocity, and mass flow rate was the same for all the tested models and a robust improvement in the newly developed models. Erosion of coal-liquid slurry in pipelines was also studied in FLUENT using the developed model UDF. The results of the study show that coal-liquid slurry causes erosion in both bent and straight pipe. The point of dense erosion was observed to have drifted along the straight pipeline as the velocity increases, which implies that little or no erosion will be observed when a very high velocity slurry flows through a short straight pipe spool. It is expected that the results of this work will be of significant help for the strengthening of the application of mechanistic models for predicting inner-wall erosive wear. This model can be effectively applied in oil and gas industries worldwide for accurate prediction of inner-wall erosive wear.

Study on the suspending mechanism of gangue particle in coal-based solid waste slurry