Thermodynamic Software Research Articles

Study on improving the fluidity of Ti2AlNb alloy

In this paper, the effects of main elements like Al, Nb and trace elements like Fe, Mo, W, Co, B and Si on the fluidity of Ti–22Al–25Nb alloy were investigated. The alloy composition which is beneficial to improve the fluidity was selected by calculating the thermal property parameters affecting the fluidity of the alloy through thermodynamic software, numerical simulation test of the fluidity of the alloy and verification test of the fluidity of the preferred alloy. Finally, the improvement mechanism of the alloy fluidity was discussed. Results showed that the appropriate reduction of Nb element was better than Al element for the improvement of fluidity. The addition of trace Fe, B and Si elements was beneficial to the improvement of fluidity, the improvement effect of B element was the best, while the addition of trace Mo, W, and Co was not conducive to the improvement of fluidity. The cessation mechanism of Ti2AlNb alloy is the cessation mechanism of the alloy with a wide crystallization temperature range. The composition which was the most beneficial to improve the fluidity was Ti–22Al–24Nb-0.1B. The main reasons for the improvement of the fluidity were that on the one hand, reducing 1 at% Nb and adding 0.1 at% B not only increased the superheat and crystallization latent heat but also reduced the melt viscosity and thermal conductivity, thus improving the fluidity. And on the other hand, the TiB phase refined the grains, and the fine grains prevented the dendrites from growing into a well-developed dendritic network, inhibited the adverse effect of the increase in the width of the solidification zone on the fluidity, and further improved the fluidity.

Al–Si–Fe alloy-based phase change material for high-temperature thermal energy storage

Abstract Carnot batteries, a type of power-to-heat-to-power energy storage, are in high demand as they can provide a stable supply of renewable energy. Latent heat storage (LHS) using alloy-based phase change materials (PCMs), which have high heat storage density and thermal conductivity, is a promising method. However, LHS requires the development of a PCM with a melting point suitable for its application. For the Carnot battery, the reuse of a conventional ultra-supercritical coal-fired power plant with a maximum operating temperature of approximately 650°C is considered. Therefore, developing a 600°C-class alloy-based PCM is crucial for realizing a highly efficient and environmentally friendly Carnot battery. Using thermodynamic calculation software (FactSage), we found that Al-5.9 mass% Si-1.6 mass% Fe undergoes a phase transformation at 576–619°C, a potential 600°C-class PCM. In this study, we investigated the practicality of an Al–Si–Fe PCM as an LHS material based on its heat storage and release properties and form stability. The examined Al–Si–Fe PCM melted until approximately 620°C with a latent heat capacity of 375–394 J·g−1. Furthermore, the PCM was found to have a thermal conductivity of approximately 160 W·m−1·K−1 in the temperature range of 100–500°C, which is significantly better than that of conventional sensible heat storage materials in terms of heat storage capacity and thermal conductivity.

Initial Pressure Optimization of Thermal Power Unit under Deep Variable Operating Conditions

Aiming at the problem of how to adjust the main steam pressure under the load instruction from the frequency modulation of the power grid to make the operation safer and more economical in the process of peak regulation, we take that 650 MW reheating condensed steam turbine as the research object. This paper introduces some domestic scholars’ research status of initial pressure optimization. The model is established by using EBSILON Professional thermodynamic system simulation software and combining it with the heat balance diagram of the power plant under VWO working conditions. The initial pressure optimization under deep variable working conditions is studied, then introduces the operation mode of the steam turbine under variable working conditions during peak shaving. The mathematical relationship between heat consumption rate and initial pressure was established to determine the feasible range of initial pressure. The exhaustive method traverses the feasible pressure interval under a particular working condition. The heat consumption rate under each pressure was calculated to screen out the optimal initial pressure and optimize the initial pressure curve.

Influence of enhanced Li content on the as-cast eutectic phase features and the evolution during homogenization of Al-Cu-Li alloys

The microstructure of Al-Cu-Li alloys is influenced by the alloying contents, which in turn affect the ultimate performance. This study examined the microstructure characteristics of Al-Cu-Li alloys with varying Li contents (1.05, 1.30, and 1.66 wt%) in as-cast state, as well as microstructure evolution during homogenization treatments. The investigation employed a range of analytical techniques, including optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), differential scanning calorimeter (DSC), focused ion beam (FIB), transmission electron microscopy (TEM), and thermodynamic calculation software. The findings indicate that the eutectic phase exhibited significant variations with the Li content changing. Three distinct low-melting phases were identified in 1.05Li alloy, including Ag-containing Al2CuMg, Al7Cu4Li, and Al2Cu. As Li content was elevated to 1.30 wt%, there was a noticeable drop in the quantities of Ag-containing Al2CuMg and Al7Cu4Li phases. Conversely, the Al2Cu phase increased, and a few Al2CuLi phases emerged. When the Li raised to 1.66 wt%, an increased Al2CuLi phase was discovered, which existed along the dendritic edges. However, there were only little Ag-containing Al2CuMg phase, and no Al7Cu4Li phase detected. The initial melting temperatures for the four soluble eutectic phases were systematically arranged in the following order: Ag-containing Al2CuMg < Al7Cu4Li < Al2Cu < Al2CuLi. The elevated Li content resulted in a challenge of dissolution of the eutectic phases. Following 500 °C/12h homogenization process, the containing-Ag Al2CuMg phase dissolved. Additionally, the Al7Cu4Li and Al2Cu phases were eliminated through subsequent 515 °C/12h homogenization. In addition, the Al2CuLi phase was still existing.

Reduced-Order Models Blend Chemistry, Machine Learning for Water-Property Analysis

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 213869, “Water Digital Avatar—Where Chemistry Is Mixed With Machine Learning,” by Jesse Farrell, SPE, and Sergey Makarychev-Mikhailov, SPE, SLB. The paper has not been peer reviewed. _ Water affects almost every operation in the exploration and production industry. Until now, time-intensive laboratory tests or cumbersome third-party simulators were required to extract physicochemical properties. In the complete paper, a family of machine-learning-based reduced-order models (ROMs) trained on rigorous first-principle thermodynamic simulation results is presented. The developed ROMs that predict water properties enable automated decision-making and improve water-management work flows. The presented approach can be extended to other oilfield, chemical, and chemical-engineering applications. Introduction The properties of the water phase and all produced fluids directly influence flow assurance, three-phase flow pressure/volume/temperature modeling, and fluid-compatibility aspects across the full life cycle of the well, including during well construction, stimulation, and production operations. Modeling these systems enables one to predict, mitigate, and, in some cases, completely prevent deleterious effects in tubing, the reservoir, and near-wellbore regions. First-principle thermodynamic simulations are often considered to be ground truth in the oilfield industry and are widely used in place of time-consuming laboratory experiments. The use of rigorous thermodynamic software, however, is not always practical. In certain cases, commercial and open-source simulators are overloaded with functionality unnecessary for a task, require training of personnel, and are often difficult to incorporate into digital work flows in the cloud or to deploy at the edge on surface equipment or the downhole tools available to model changing conditions in real time. This is where ROMs find their application because they are fast, reasonably accurate, and highly customizable solutions. The authors’ scientific hypothesis was that machine-learning-based ROMs can be used to quantify the physicochemical properties and scaling tendencies of oilfield waters in place of rigorous, first-principle thermodynamic models. Methods The United States Geological Survey (USGS) Produced Waters Geochemical Database was used as the initial data source for this study. The original database contains approximately 115,000 produced-water and other deep-formation water samples collected and characterized in the United States in the past 120 years. Although the USGS database is an excellent source, the data still required cleaning and enrichment. For the first step, inconsistent, poorly populated, and outlier samples were removed, which led to noticeable data attrition and resulted in approximately 85,000 “clean” records. The enrichment phase included several manipulations and alterations of the original data. The resulting data set is not always accurate regarding individual samples but is much better populated than the original one in terms of minor ion concentrations, and is believed to be representative on a large scale.

Formation and aggregation behavior of inclusions in Ni-based alloys with different Mg contents

Large non-metallic inclusions affect the mechanical properties and service life of nickel-based superalloys. This study investigates the effects of magnesium elements on non-metallic inclusions in K4169 nickel-based superalloys, exploring the formation mechanisms and aggregation relationships of the inclusions. Four gradients of the magnesium content were used to simulate the erosion of MgO refractories on inclusions in the vacuum induction melting of nickel-based superalloys. The observed inclusions mainly comprised MgO, TiN, MgAl2O4, and MgAl2O4–TiN composites. To study the formation mechanism of inclusions in Ni-based alloys with different Mg contents, the predominance diagram of Mg–Al–Ti–O inclusions in nickel-based superalloy systems was calculated using Factsage thermodynamics software and classical thermodynamics separately. The aggregation behavior of MgAl2O4 and MgO inclusions on the surface of molten nickel-based superalloys was observed in situ under a high-temperature confocal laser scan microscope. The capillary force acting on inclusions in nickel-based superalloys was calculated using the Kralchevsky–Paunov model (K–P model), the calculation was verified with experimental results, and the influencing factors were analyzed. The capillary force acting on inclusions on the surface of molten nickel-based superalloys weakened in the order of MgAl2O4 > MgO > Al2O3, which is the opposite of the order for the force acting on inclusions in molten steel. Minimizing the magnesium content in the alloy is crucial to preventing the formation of large inclusions in nickel-based superalloys, and the use of magnesium-containing materials in the smelting process should thus be avoided.

Simultaneous recovery of valuable metals W, Co, Ta, and Nb from tungsten leaching residue by sodium-based slag refining

As a hazardous solid waste in the tungsten (W) materials industry, the utilization of W leaching residue (W-residue) has become a challenge. In this study, we propose a sustainable strategy for the simultaneous extraction of valuable elements W, Ta, Nb, and Co from W-residue by a sodium-based slag refining. The slag system was designed to provide a slag-liquid phase to facilitate the mass transfer and reduction reaction of the valuable metallic compounds during the refining process. The characteristics of Na2O-SiO2-NaF slag system, including the liquidus temperature and viscosity, were predicted using FactSage thermodynamics software and evaluated experimentally. Using 0.5Na2O-0.3SiO2-0.1NaF slag, the recovery efficiency of the valuable elements from W-residue can reach 94%(W), 66%(Co), 53%(Ta), and 77%(Nb), and a total recovery rate was reached 75%. The mechanism illustrated that the valuable elements (W, Co, Ta, and Nb) in W-residue can be transformed to (W, Ta, Nb, Ti)C and (Fe, Co)Si, which co-precipitated as alloy phases during the slag refining process. The present work offers a strategy, not merely limited to waste utilization of W-residue, to supplement the recycling route of W materials industry.

Hydration and Fractal Analysis on Low-Heat Portland Cement Pastes Using Thermodynamics-Based Methods

Low-heat Portland (LHP) cement is a kind of high-belite cement, which has the characteristic of low hydration heat. Currently, it is extensively used in the temperature control of mass concrete. Based on the thermodynamic database of OPC-based materials, the thermodynamic software GEM-Selektor (noted as GEMS) is used for simulating the hydration products of the LHP cement paste. Then, according to the GEMS thermodynamic simulation results, MATLAB is used to visualize the initial and ultimate stages of LHP cement pastes; the effects of curing temperature and water to cement (w/c) ratio on hydration products are addressed; and the porosity, fractal dimension, and tortuosity of different pastes are calculated. It is found that an appropriately high curing temperature is important for reducing porosity, especially in the early hydration stage. Hydration time also has a significant impact on the hydration of LHP cement paste; long hydration time may reduce the impact of temperature on hydration products. The w/c ratio is another important consideration regarding the hydration degree and porosity of LHP paste, and under different curing temperatures, hydration times, and w/c ratios, the porosity varies from 5.91–32.91%. The fractal dimension of this work agrees with the previous findings. From tortuosity analysis, it can be concluded that the high curing temperature may cause significant tortuosity, further affecting the effective diffusivity of LHP cement paste. For cement pastes with low w/c ratio, this high curing temperature effect is mainly reflected in the early hydration stage, for ones with high w/c ratio, it is in turn evident under long-term curing.

A methodology to determine the precision uncertainty in gas turbine engine cycle models

Abstract This paper proposes a methodology to define and quantify the precision uncertainties in aerothermodynamic cycle model comparisons. The total uncertainty depends on biases and random errors commonly found in such comparisons. These biases and random errors are classified and discussed based on observations found in the literature. The biases account for effects such as differences in model inputs, the configurations being simulated, and thermodynamic packages. Random errors consider the effects on the physics modeling and numerical methods used in cycle models. The methodology is applied to a comparison of two cycle models, designated as the model subject to comparison and reference model, respectively. The former is the so-called Aerothermodynamic Generic Cycle Model developed in-house at the Laboratory of Applied Research in Active Control, Avionics and AeroServoElasticity (LARCASE); the latter is an equivalent model programmed in the Numerical Propulsion System Simulation (NPSS). The proposed methodology is intended to quantify the bias and random errors effects on different cycle parameters of interest, such as thrust, specific fuel consumption, among others. Each bias and random errors are determined by deliberately preventing the effects from other biases and random errors. The methodology presented in this paper can be extended to other cycle model comparisons. Moreover, the uncertainty figures derived in this work are recommended to be used in other model comparisons when no better reference is available.

A Thermodynamic Simulation Package for Catalytic Polyolefin Reactors: Development and Applications

A Thermodynamic Simulation Package for Catalytic Polyolefin Reactors: Development and Applications

Analysis of Phase Transformations in Fe-Ni-Al Alloys Using Diffusion Couples of Fe/Fe-33at.%Ni-33at.%Al Alloy/Ni

The present work focused on analyzing the phase transformation in Fe-Ni-Al alloys employing a diffusion couple of Ni/Fe-Ni-Al/Fe, and Calphad-based diffusion and thermodynamic software. Diffusion couples were prepared by annealing at 1100 °C for 200 h and then air-cooled. These couples were also aged at 750 °C for 100 and 275 h. Both numerical and experimental results indicated that the diffusion path between Ni or Fe pure metal and the Fe-33at.%Ni-33at.%Al alloy is not linear. The phases formed during the diffusion anneal at 1100 °C correspond to those shown in the Calphad-calculated Fe-Ni-Al equilibrium diagram. The aging treatment at 750 °C promoted the inverse precipitation β′ → β′ + α, which caused the softening of the alloy. Moreover, the normal precipitation reactions, α→α + β′ and γ → γ + γ′, were also observed to occur during the aging of diffusion couple at 750 °C, originating precipitation hardening.

Effect of oxygen on trace impurities in extremely pure metal ingots used for realising ITS-90 fixed point temperatures

The International Temperature Scale of 1990 (ITS-90) provides a scheme for calibrating thermometers which is largely based on the freezing points of pure metals such as indium, tin, zinc, aluminium and silver. The existence of trace impurities in pure metals results in uncertainties in the realization of these freezing points. Several methods such as the sum of individual estimates (SIE) and overall maximum estimate (OME) are used to assess the uncertainties due to the presence of impurities. However, it is becoming evident that the oxidation of impurities results in their precipitation, which means that these insoluble oxides no longer play a significant role in the elevation or depression of the freezing temperature. Hence the conventional correction techniques may overestimate the magnitude of the effect. In this study, the thermodynamic modelling software MTDATA was used to evaluate the effect of oxygen on selected impurities in In, Sn, Zn, Al and Ag by calculating the binary impurity-metal phase diagram in the presence of specific amounts of oxygen. It was found that oxygen has a significant effect on many of the systems studied. The most significant effect was observed in the Ag system, and then, in decreasing order of significance, In, Sn, Zn and Al.

Thermodynamic Calculation of 2618 High Performance Aluminum Alloy

The thermodynamic-related physical parameters, precipitation amount of equilibrium phase, and initial precipitation temperature of Al-(1.9–2.5) Cu-(1.2–1.8) Mg-(0.9–1.5) Fe-(0.9–1.5) Ni alloy were simulated by using the thermodynamic simulation software JMat-Pro. The results show that with the change of element content, the liquidus temperature is in the range of 641.92–638 °C. The precipitation transition temperature of the eutectic phase with a low melting point ranges from 515 °C to 517.25 °C. The solidus temperature is closely related to Cu/Mg. The dendrite spacing decreases with the increase of Mg and Fe (Ni) contents, among which Mg has the greatest influence, followed by Fe (Ni) and Cu. The partial molar Gibbs free energy of Cu, Mg, Fe, and Ni is negative. The activity of Mg increases with the decrease in temperature, and the maximum activity is 0.10189, while the activities of Cu, Fe, and Ni are close to 0. The initial precipitation temperatures of S(Al2CuMg) and Al9FeNi phases are 424–450 °C and 635.4–643.01 °C, respectively. The initial precipitation temperature of the Al9FeNi phase decreases with the increase of Cu and Mg contents, while it increases with the increase of Fe (Ni) contents. With the increase of Cu and Mg contents, the initial precipitation temperature of S(Al2CuMg) increases and decreases with the increase of Fe (Ni) contents. The precipitation amount of S(Al2CuMg) mainly depends on the content and ratio of Cu and Mg, while that of Al9FeNi increases with the increase of Fe and Ni elements in the same proportion.

A New Thermodynamic Model to Approximate Properties of Subcritical Liquids.

In order to obtain the thermodynamic properties of compressed liquids, it is usual to consider them as incompressible systems, since liquids and solids are well represented by this thermodynamic model. Within this model, there are two usual hypotheses that can be derived in two different submodels: the strictly incompressible (SI) model, which supposes a constant specific volume v=v0, and a more general model, called temperature-dependent incompressible (TDI) model, which relates a specific volume to temperature, v=vT. But, usually, this difference ends here in the thermal equation of state, and only the SI model was developed for caloric and entropic equations. The aim of this work is to provide a complete formulation for the TDI model and show where it can be advantageously used rather than the SI model. The study concludes that the proposed model outperforms the traditional model in the study of subcritical liquid. One conceivable utilization of this model is its integration into certain thermodynamic calculation software packages (e.g., EES), which integrate the more elementary SI model into its code for certain incompressible substances.

Study on volatilization behaviour of BOF converter slag containing CaCl2

ABSTRACT The volatilization behaviour of CaCl2-containing basic oxygen furnace (BOF) slags was investigated in laboratory at steelmaking temperature. During the melting process, the volatilization ratio was measured, and the volatile compounds were collected with some conductive tapes. Thermogravimetric analysis was conducted to clarify the volatilization of CaCl2-containing slags, and the volatilization ratio was also calculated by the thermodynamic software HSC. It was found that volatilization takes place in both CaCl2-containing and CaF2-containing BOF slags, but their influential mechanisms are different. FeCl2 is the main volatile compound in CaCl2-containing BOF slags. The increasing contents of CaCl2 and FeO in these slags are favourable for volatilization, while higher slag basicity plays the opposite role. In the case of CaF2-containing BOF slags, the volatilization compounds have little relation to the FeO content in the slags, and the volatilization ratio is smaller than that of CaCl2-containing BOF slag.

Effect of MgO on wetting and corrosion behaviour of corundum substrate by CaO–SiO2–MgO (–Al2O3) slags

ABSTRACT Effect of MgO content on wetting and corrosion behaviour of corundum substrate by CaO–SiO2–MgO (−15%Al2O3) molten slags was investigated at 1450°C via joint application of a sessile drop technique, SEM–EDS detection and FactSage thermodynamic software. All slags exhibit good wettability on the substrate, and the contact angle values are small. Increasing MgO content from 7% to 9% in CaO-SiO2-MgO slags can increase the contact angle between the droplet and the substrate, while the substrate dissolution thickness and the slag penetration depth tend to decrease. Increasing MgO content from 8% to 15% in CaO-SiO2-MgO-15% Al2O3 slags can also increase the contact angle, but significantly decrease the slag penetration depth. The indirect dissolution thickness increases instead due to the formation of a large amount of MgAl2O4 by the interface reaction. The wettability can give an indication of the slag penetration depth in the substrate but not the dissolution thickness of the substrate.

The Effect of SiC on the Phase Composition and Structure of Mixed Slag

In order to investigate the influence of SiC on the composition and structure of mixed slag (blast-furnace slag: steel slag = 1:9), the chemical composition, equilibrium-phase composition, and microscopic morphological characteristics and elemental distribution in the microscopic region of the SiC-reagent-tempered slag samples were analyzed by X-ray diffractometer (XRD), FactSage7.1 thermodynamic analysis software, scanning electron microscope, and energy spectrum analyzer. It was found that the main physical phases of the tempered slag samples were magnesia–silica–calcite (Ca3Mg(SiO4)2, C3MS2), calcium–aluminum yellow feldspar (Ca2Al2SiO7, C2AS), C2S, and iron alloy. Theoretical calculations suggest that the experimental temperature should be higher than 1500 °C to facilitate the combination of P5+ with Fe and Mn in the liquid phase to form an alloy, reduce the P5+ content in the tempered slag, and create conditions for the self-powdering of the conditioned slag. The doping of the SiC reagent can increase the liquid phase line temperature and reduce the binary basicity in the liquid phase; the liquid phase line temperatures were 1150 °C, 1200 °C, and 1300 °C and the basicities in the liquid phase were 4.68, 4.13, and 3.10 for the doping amounts of 3%, 4%, and 5% of the SiC reagent, respectively. The mixed slag doped with 4% SiC reagent achieves self-powdering and reduction of ferroalloys during the air-cooling and cooling processes, realizing the purpose of “resource utilization” of blast-furnace slag and steel slag.

Flexible operation, optimisation and stabilising control of a quench cooled ammonia reactor for power-to-ammonia

This paper discusses the operation of an ammonia reactor for a Power-to-Ammonia (P2A) plant. We develop a dynamic model for an ammonia reactor system consisting of a three-bed quench cooled adiabatic reactor and a feed-effluent heat exchanger. The reactor bed model is formulated as a differential algebraic equations (DAE) system. We use the thermodynamic software Thermolib for rigorous modelling of the thermodynamic functions in the high pressure ammonia reactor. We present a case study of an ammonia synthesis loop in a P2A plant connected to a 250 MW renewable energy source with a capacity factor of 0.4. Static optimisation and stability analysis are performed for the reactor system, which located the optimal operating point close to instability. The dynamic simulations confirm the unstable operating regions as severe oscillations arise. A fluctuating energy supply from renewable sources requires the ammonia reactor to operate over a wide operating window from 20%–120% of nominal capacity. We formulate a realistic strategy for varying the supply of H2 and N2 (load) to the synthesis loop depending on the available energy. Open-loop simulations show that varying the synthesis feed flow cause oscillations in the ammonia reactor system. Therefore, we propose a regulatory control structure for stabilising the ammonia reactor. The optimisation algorithm determines the reactor set-point state by updating at changes to the synthesis loop load. Hereby, we achieved fast control and close tracking of the set-points for the ammonia reactor.

Thermodynamic Analysis of Mineral Phase Composition of Steel Slag System

In order to transform the crystalline form of Ca2SiO4 (C2S) in phosphorus-containing slag from monoclinic β-polycrystalline to square γ-polycrystalline, a volume expansion of about 11% was generated, which caused the phosphorus-containing slag to undergo self-powdering. The CaO-SiO2-Al2O3-MgO-MnO-P2O5-FeO slag system was analyzed using FactSage7.1 thermodynamic software, and the effects of different P2O5, FeO and basicity on the mineral phase composition of slag system were analyzed in the range of 1300~1700 °C. It was shown that P2O5, FeO and basicity all have an effect on the composition of the mineral phases. When the mass fraction of P2O5 in the slag was lower than 0.25%, it had less effect on the transformation of C2S crystalline structure. When the P2O5 content was higher than 0.25%, it was favorable to the generation of low-melting-point substances, but the P2O5 in the slag reacted with C2S in the silicate phase, making P5+ solidly soluble in C2S, inhibiting the transformation of β-C2S to γ-C2S and hindering the self-powdering of the slag. The FeO content in the slag system ranged from 20% to 28%, and as the FeO content increased, the C2S content in the silicate phase decreased from 33.3% to 25.9%, while the temperature at which the silicate was completely dissolved into the liquid phase decreased from 1600 °C to 1500 °C and the complete melting temperature of the slag decreased. The low FeO content facilitates the self-powdering of slag. In the high-phosphorus slag, at temperatures below 1450 °C, with the increase of basicity, the proportion of C2S in the silicate phase first increased and then decreased. With basicity at 1.8; the highest content of silicate phase, accounting for 33.7%; and the temperature exceeding 1450 °C, the silicate phase dissolved into the liquid phase, which is conducive to the removal of phosphorus from the slag, achieving the self-powdering of high-phosphorus slag.

Removing Ti5Si3 phase in Ti alloy via desilication of upgraded titania slag using low-temperature alkali leaching

Silicon in two types of upgraded titania slag (UGS) containing different components was removed using a low-temperature alkali solution and melt leaching. The effects of temperature, time, and NaOH solution concentration on desilication rate were investigated. Desilication in melt can lead to the loss of titanium in upgraded titania slag. After agitating at a speed of 600 r/min and 80 °C for 300 min, the silicon content in domestic slag decreased from 0.96 wt.% to 0.29 wt.%, and the leaching rate was 69.8% after leaching in 4 mol/L sodium hydroxide solution. Under the same conditions, the silicon content in imported slag decreased from 1.11 wt.% to 0.12 wt.%, and the desilication rate was up to 89.2%. The alloy powders obtained from the reduction of upgraded titania slag with magnesium were sintered to produce titanium alloy, and the alloy was characterized. It was determined that the Ti5Si3 phase in the titanium alloy product was successfully eliminated. In addition, the two UGS materials and the chemical principle of desiliconization were analyzed using a thermodynamic software.