High Pressure Temperature Conditions Research Articles

Phase Stability and Hydroxyl Vibration of Brucite Mg(OH)2 at High Pressure and High TemperatureSupported by the National Key Research and Development Program of China (Grant No. 2019YFA0708502).

Brucite Mg(OH)2 is an archetypal hydrous mineral and it has attracted a great deal of attention. However, little is known about the evolution of hydroxyl groups in brucite with respect to subduction fluids. We carried out Raman measurements up to 15.4 GPa and 874 K via an externally heated diamond anvil cell, investigating the stability of brucite under the conditions relevant to subducting slabs. The hydroxyl vibration mode A 1_g(I) of brucite is weakened under simultaneous high pressure-temperature conditions. Meanwhile, the presence of carbonated solution can destabilize the hydroxyl groups of brucite at low pressure. Our results suggest that brucite releases water when reacting with hydrogen carbonate ion to form magnesite MgCO3 in subduction zones. This implies that the global water cycle is largely coupled with the deep carbon cycle in Earth’s interior.

Facile fabrication of ultra-robust underwater superoleophobic coating with remarkable self-cleaning performance in harsh environments

Preparation of robust oil-repellant surfaces in aqueous environment with mechanical stability is imperative, yet challenging for the extensive range of real applications where high durability is required. We report the robust underwater superoleophobic properties of mineral surfaces coated with a nanofluid based on synthesized TiO2/Al2O3 nanocomposites functionalized by poly(vinyl alcohol) (PVA). The produced nanofluid demonstrated predominant stability in harsh environments including acid/base solutions, saline solutions with strong ionic strength and high temperature–high pressure conditions. The sandpaper abrasion test (grit numbers 400, 240 and 180; 57 kPa) exhibited that the obtained coating retains its functions significantly after suffering the abrasion distance of 16000 cm. Meanwhile, the multifunctional coating nanofluid impart properties of self-cleaning. A crude oil droplet released at height of 9 mm from the coated surface undergoes first a lateral movement from its trajectory and misshaping, touching the surface after 300 ms, bouncing and rolling off easily with no tilt of solid substrate. This durable underwater superoleophobic nanofluid has thermal stability up to 150 °C; novel industrial applications include within Chemical Enhanced Oil Recovery (CEOR) methods applied to produce trapped oil from naturally oil-wet reservoirs.

Experimental study of spontaneous imbibition for oil recovery in tight sandstone cores under high pressure high temperature with low field nuclear magnetic resonance

Spontaneous imbibition (SI) plays a key role in production mechanism of unconventional reservoirs. Trivially, with the goal of getting higher efficiency there always has been an incessantly research activities to develop the technology progressively. In this regard, thermodynamic variables (i.e. pressure and temperature) can directly influence the process performance of SI. Thus, numerous papers have been published by considering normal conditions (e.g. 20 °C, 0.1 MPa), high pressure (HP) or high temperature (HT). To bridge an existing gap in the literature, an inhouse built imbibition experimental setup was used to carry out the SI under high pressure-high temperature (HPHT) conditions (50 °C, 10 MPa). The core samples used in this study were tight sandstone taken from Yanchang formation, Ordos Basin. Experimental conditions were: 1) simulated formation conditions (50 °C, 10 MPa), 2) normal condition (20 °C, 0.1 MPa), 3) pulse imbibition (20 °C, 8/4 MPa in cyclic alteration) and 4) simulated formation conditions (50 °C, 10 MPa) for fractured cores (1/3 and 2/3 length). Moreover, NMR was employed to characterize the dynamic behavior of imbibition for each sample. It was found, samples tested under HPHT conditions yielded higher imbibition efficiency (average of 63.49%) compared to ambient conditions (27.31%). and imbibition efficiency of HPHTSI (max, 73.47%, min, 55.23%) showed early imbibition with higher rate. Ultimately, micropores had the largest imbibition efficiency and matrix core samples exhibited lower recovery than fractured ones (74.6%). Collectively, this study presents the importance of fracture-matrix interaction in tight sandstones which is a crucial component for higher recovery rates.

BaFe[CO3]2, a new double carbonate: Synthesis, structural characterisation, and geostability implications for high and low PT

For the first time, a new ordered double carbonate, BaFe(CO3)2, was synthesized by a solid-state reaction between BaCO3 and FeCO3 at high pressure-temperature conditions (PT; 3 GPa and 700 °C). This finding adds a new so-far unknown member to the group of norsethite-structured carbonates, which is often used as a geochemical analogue for dolomite. Thermogravimetric (TG) analysis and differential scanning calorimetry (DSC) reveal that BaFe(CO3)2 decomposes between temperatures of 450 °C and 880 °C, which is similar to norsethite (BaMg(CO3)2), but substantially higher than of pure FeCO3. The formation of BaFe(CO3)2 through solid-state reaction is evidently slower than that of BaMg(CO3)2 and BaMn(CO3)2 under the same experimental conditions. Using synthetic BaFe(CO3)2 powder as starting material, the reaction in the presence of CO2-bearing solution in contrast to water as a flux medium indicates the BaFe(CO3)2 instability at high PT conditions. The crystal structure and composition of the double carbonate were obtained using single crystal X-ray diffraction (XRD), Raman spectroscopy, and electron probe (EP) analysis. Two different types of the new double carbonate were identified: The experimentally derived phase belong to crystal structures that are related to the R3¯m and R3¯c space groups, respectively. The Raman spectra indicated that the difference is caused by a superstructure parallel to the c-axis. The charge and spin states of Fe in the new phases is determined using Nuclear forward scattering of synchrotron radiation. Furthermore, the thermodynamic properties of the double carbonate at standard conditions are estimated and a phase diagram is constructed depicting the stability field in low-temperature aqueous environments with these results being compared to natural aqueous solutions.

Impact of surface fluorination on phase stability of nanodiamond particles and inter-granular bonding in polycrystalline diamond under HPHT conditions

Polycrystalline diamond (PCD) compacts, made by conventional high pressure-high temperature (HPHT) technology, contain Co catalyst in inter-granular spaces causing degradation of PCD mechanical strength and thermal stability during rock cutting due to thermal expansion and graphitization. To solve this problem a catalyst-free synthesis of PCD based on HPHT sintering of fluorinated nanodiamond (FND) and submicron size aluminum mixtures was explored in the present work. The feasibility of using FND has been established by evaluation of phase stability of FNDs of 5, 10, and 90 nm sizes under industrially favorable P-T conditions (7.5–8 GPa, 1500–1700 °C) for PCD synthesis. It was found that surface fluorine slows down the graphitization of nanodiamond particles. Enlargement of diamonds from 5 and 10 nm up to a 10 μm has been observed for FND/Al systems. This phenomenon can be associated with the Wurtz-type reaction under the HPHT conditions leading to formation of inter-granular carbon‑carbon bonds between the nanoparticles and formation of the fluid Al-C-F phases in the samples volume, accelerating the mass transport and re-crystallization of nanodiamond. PCD samples sintered from mixtures of fluorinated micro-diamonds, nano-diamonds FND-90 and 3 wt% aluminum exhibited enhanced up to 1200 °C thermal stability and as high wear resistance as leached commercial PCD.

Tannin-Based Deflocculants in High Temperature High Pressure Wells: A Comprehensive Review

Clay deflocculants that are commonly used in water-based muds under high temperature high pressure (HTHP) oilwell drilling conditions have been found to contain chromium which is toxic. Tannin-based deflocculants are regarded as a more environmentally friendly and suitable alternative to the chrome-based deflocculants. However, tannin-based deflocculants have not been studied extensively and understood completely, and for the past two years, there have not been many active pieces of research in the area. To advance research in the area, there is a need to critically and holistically review research works that have been done so far on tannin-based deflocculants as drilling mud additives to identify research challenges and opportunities. This review paper provides an overview of tannin-based deflocculants used in water-based muds under HTHP drilling conditions, including the various forms, thermal stability, deflocculating ability and environmental acceptance of the deflocculant. The review revealed that under HTHP conditions, modified and unmodified tannin-based deflocculants both deflocculate water muds well and are thermostable. However, only a few studies have been conducted on their usage as deflocculants at temperatures of 150oC or above. The research gaps identified if pursued could advance the use of tannin-based deflocculants as green substitutes for the conventional chrome-based deflocculants.

Enhancing Hematite-Based Invert Emulsion Mud Stability at High-Pressure High-Temperature Wells.

Drilling fluids have a crucial continued role in drilling a successful well; however, most of the drilling technical and operational challenges are incorporated with the drilling mud stability and properties. The solid particles settling in drilling mud that deteriorates its stability is a common issue encountered in high-pressure high-temperature (HPHT) conditions. This issue, known as solids sagging, may eventually result in stuck pipes, wellbore instability, and loss of circulation. The objective of this work is to introduce garamite to enhance the stability of hematite-based invert emulsion mud under HPHT situations. The used garamite and hematite weighting material were analyzed using X-ray fluorescence, scanning electron microscopy, and particle size distribution to identify their compositions, morphologies, and particle sizes. The effects of adding different concentrations of garamite (0.5, 1.0, 1.25, and 1.5 g) to the field formula of hematite-based invert emulsion mud were investigated. The mud density, stability, sagging tendency, rheology, viscoelasticity, and filtration properties were studied to formulate a stabilized and distinguished-performance drilling mud. The obtained results indicated that garamite did not change the mud density while enhancing the emulsion stability by increasing the electrical stability proportionally with the added garamite quantity. The sagging experiments showed that adding 1.25 g of garamite is sufficient to prevent the sagging problem in both static and dynamic conditions as it was enough to enforce the sag parameters into the safe range of sag performance indicators. This 1.25 g of garamite improved the yield point by 152% from 19 to 48 lb./100 ft2 with a slight increase in plastic viscosity from 14 cP for base mud to 18 cP and significant increase in the gelling strength and viscoelastic properties. Adding 1.25 g of garamite showed a slight enhancement in the filtration properties as the filtrate volume was reduced by 8% from 3.7 to 3.4 cm3 and the filter cake thickness has 16% reduction from 2.69 to 2.26 mm. As a result, a mud with distinguished performance, in terms of rheology, suspension, sag performance, and stability, was obtained. Hence, a basis for safely drilling the HPHT formations was delivered, which reduces the drilling cost by minimizing the nonproductive time.

Experimental Investigation of Noble Viscoelastic Surfactant and Chelating Agent for Heavy Oil Enhanced Oil Recovery in High‐Pressure–High‐Temperature Carbonate Reservoirs

AbstractThe success of chemical enhanced oil recovery (cEOR) is significantly dependent on the type of reservoir and its pressure and temperature conditions. The recovery of heavy oil from carbonate reservoir using cEOR method is still challenging because of its highly complex internal structures and high pressure–high temperature (HPHT) conditions. This research work is the first account of the use of AGA‐97 (viscoelastic surfactant [VES)) along with a chelating agent diethylene triamine penta acetic acid (DTPA) for their application in cEOR method in heavy‐oil‐carbonate reservoirs. Several core flooding experiments were carried out to ascertain the effectiveness of the VES AGA‐97 and chelating agent for cEOR method. The effect of VES on viscosity and interfacial tension was also studied with varying concentration, temperature, and time. The thermal stability of VES was analyzed with the help of thermogravimetric analysis, nuclear magnetic resonance (NMR) and Fourier‐transform infrared spectroscopy. VES AGA‐97 was found to have high thermal stability in short‐term aging. The static adsorption and dynamic adsorption of VES AGA‐97 was studied with the help of total organic carbon analysis. After all the analysis, it was found that VES AGA‐97 and DTPA can be effectively used for cEOR method in carbonate reservoir at HPHT conditions, and the total additional oil recovery of 5.82–9.64% may be achieved.

Self-welding of Inconel 617 under high-pressure-high-temperature conditions for nuclear reactors

In response to continuously declining availability of fossil fuels, nuclear power has become an important alternative source of power generation. Growing application of nuclear power has relieved the shortage of electricity. However, it is also accompanied with new drawbacks, such as radioactive waste, and potential catastrophic consequences in case of major accidents. For nuclear power plants, severe accidents mostly originate from the reactor, making the reliability of the reactor of paramount importance to the overall safety of a nuclear power plant. Massive heat generation through nuclear fission/fusion and heat exchange render the whole reactor operating at extremely high temperatures (i.e., 900–1000 °C), which, in conjunction with large load from subsystems/ components made of special heavy alloys, renders the reactor under the risk of self-welding, a phenomenon that could lead to strong bonding between components and paralyze the operability of the nuclear reactor. This paper investigates the self-welding behavior of Inconel 617, a primary candidate nickel alloy for key components of the next generation gas cooled nuclear plant, inside a controlled atmospheric furnace with preset static load, simulating the high-pressure high-temperature conditions inside nuclear reactors. Test results show that Inconel 617 experiences self-welding through common oxide zone at the interface, and it has remarkable bonding strength, requiring 4114 N (57.15 MPa) and 4338 N (60.25 MPa) to break apart a mated sample pair, under an apparent contact pressure of 0.341 MPa after 50-h aging, in helium and air atmospheres, respectively. The higher oxygen presence in air results in slightly stronger oxide bond at the interface, compared to helium, and the bond strength increases with dwell time.

Perspective for elasticity of minerals in the Earth's top lower mantle.

The elasticity of minerals under high pressure-temperature conditions is crucial for constraining mantle composition. This perspective highlights recent advances in experimental and theoretical work in determining the elasticity of minerals to resolve the origin of low-velocity layers and the seismic anisotropy in the top lower mantle.

An integrated FMEA and MCDA based risk management approach to support life extension of subsea facilities in high-pressure–high-temperature (HPHT) conditions

The majority of facilities installed in offshore oil and gas fields during the 1980s and 1990s were designed to operate in ‘normal’ conditions. However, during the operational life of the fields, some new high pressure/high temperature (HPHT) wells may be discovered and tied back to older facilities. Operating these facilities beyond their design parameters in harsh environments may lead to catastrophic failures, resulting in significant economic losses and environmental problems. Managing the risks associated with failure of ageing subsea facilities in HPHT environments is considered as a very complex and critical task. To overcome such challenge, there is a need for development of decision-making methods that are capable of estimating precisely the risks associated with HPHT conditions as well as prioritising the risk mitigation and remediation strategies. This paper aims to propose an integrated risk management framework – based on Failure Mode and Effects Analysis (FMEA) approach and a hybrid Multi-Criteria Decision Analysis (MCDA) model – for evaluating the risks and prioritising mitigation strategies over the extended lifetime of subsea facilities in HPHT environments. For the purpose of illustrating the model, a case study of subsea manifold and flowlines is provided and the results are evaluated and discussed. Our findings indicate that the proposed approach offers significant improvement to the classical risk management processes applied to subsea oil and gas facilities as it can assist asset managers, risk analyst, regulators and policy makers with a decision model which considers both subjective (qualitative) judgements and objective (quantitative) evaluation measures.

Integrated Approach for the Wellbore Instability Analysis of a High-pressure, High-temperature Field in the South China Sea

Wellbore instability and lost circulation were frequently encountered while drilling the first batch of exploration wells in a low-permeability, high-pressure, high-temperature (HPHT) gas field in the South China Sea. These problems are attributed to very narrow drilling mud weight windows resulting from the HPHT reservoir conditions. This study focuses on combining and leveraging geophysical data, rock mechanics testing data, and well logging data to predict wellbore instability and lost circulation under HPHT conditions. Full-scale core samples were acquired from HPHT reservoirs of the field, and uniaxial and triaxial rock mechanics tests were performed to determine the mechanical properties of the rock. The influence of heat transfer between the wellbore and the formation, temperature field, mechanical properties, in situ stresses, collapse pressure, and fracture pressure were investigated. According to the results, changes in wellbore temperature generate thermal stress, which may aggravate wellbore instability. The wellbore temperature decreased by 50–60°C during the mud circulation process. Furthermore, the safe mud weight window, which was originally narrow because of the HPHT conditions, became narrower under the influence of temperature change. The use of multi-source data and the integrated model will significantly improve the accuracy of wellbore instability and lost circulation prediction in HPHT fields.

Optical and electronic solutions for power stabilization of CO2 lasers.

High pressure-temperature conditions can be readily achieved through the laser-heated diamond anvil cell (LH-DAC). A stable laser source is required for reliable in situ measurements of the sample, as the sample is small with a thermal time constant of the order of microseconds. Here, we show that the power instabilities typical of CO2 gas lasers used in LH-DAC's are ±5% at the second timescale and ∼±50% at the microsecond timescale. We also demonstrate that the pointing instability of the laser requires either a diffuser or an integrating sphere for reliable total power measurements with small sized detectors. We present a simple solution for stabilizing the power of a CO2 gas laser on the second timescale by the direct modulation of the current across the tube and another solution that stabilizes the power to the microsecond timescale by externally modulating the CO2 laser beam. Both solutions can achieve a ±0.3% power stability.

Hydrogeochemical modeling of water injection into an oil and gas well under high-pressure high-temperature (HPHT) conditions

Approximately 80% of water extracted from oil and gas deposits in Poland is disposed of by injection into the rock matrix. The aim of the model research was to predict both the hydrochemical reactions of water injected into wells for its disposal and the hydrogeochemical processes in the reservoir formation. The purpose of hydrogeochemical modeling of the hydrocarbon formation was also to determine the potential of formation waters, injection waters, and their mixtures to precipitate and form mineral sediments, and to determine the corrosion risk to the well. In order to evaluate saturation indices and corrosion ratios, the geochemical programs PHREEQC and DownHole SAT were used. The results of hydrogeochemical modeling indicate the possible occurrence of clogging in the well and the near-well zone caused mainly by the precipitation of iron compounds (iron hydroxide Fe(OH)3 and siderite FeCO3) from the formation water due to the presence of high pressures and temperatures (HPHT). There is also a high certainty of the precipitation of carbonate sediments (calcite CaCO3, strontianite SrCO3, magnesite MgCO3, siderite FeCO3) from the injection water within the whole range of tested pressures and temperatures. The model simulations show that temperature increase has a much greater impact on the potential for precipitation of mineral phases than pressure increase.

Temperature dynamics and its effects on gas influx handling during managed pressure drilling operations

With Managed Pressure Drilling (MPD) becoming increasingly important to oil and gas well construction, there has been a growing demand for comprehensive models that can accurately describe the well hydraulic dynamics, especially for complex well geometries, High-Pressure High-Temperature (HPHT) conditions, during well control events, etc. To meet this demand, new multi-phase hydraulic models have been developed. However, despite their improvement over the traditional lumped parameter models, these models typically do not consider detailed temperature effects, which markedly influence well hydraulics and need to be explicitly considered for accurate MPD control.The development of a new integrated multi-phase thermal and hydraulic modeling framework is presented in this paper. This integrated model can estimate the mud temperature in the drillstring and the annulus, as well as the temperature variations of the formation during complex well control situations. The model uses a semi-implicit finite volume approach and solves the mixture energy equation for the wellbore fluids, assuming that all the phases are in thermal equilibrium. Heat transfer between the drillstring and wellbore fluids, and between the wellbore fluids and the formation is calculated using thermal resistance networks.The steady-state and transient temperature behaviors during mud circulation are compared to the steady-state analytical model by Hasan and Kabir and commercial software. These comparisons show good agreement for both steady-state and transient cases. To demonstrate the importance of accurate temperature estimation of the drillstring and annulus fluids in HPHT conditions, offshore kick scenarios for non-aqueous drilling fluids and dynamic kick control methods are simulated. Simulation results indicate that the model enables real-time estimation of crucial parameters during well control, such as the wellbore pressure and temperature profiles, increased outflow and pit gain during kicks, gas thermodynamic behavior including solubility and unloading behavior at low pressure conditions, gas rising velocity, and temperature-dependent formation strength.

Oxidation of the Interiors of Carbide Exoplanets

Abstract Astrophysical measurements have shown that some stars have sufficiently high carbon-to-oxygen ratios such that the planets they host would be mainly composed of carbides instead of silicates. We studied the behavior of silicon carbide in the presence of water under the high pressure–temperature conditions relevant to planetary interiors in the laser-heated diamond-anvil cell. When reacting with water, silicon carbide converts to silica (stishovite) and diamond at pressures up to 50 GPa and temperatures up to 2500 K: . Therefore, if water can be incorporated into carbide planets during their formation or through later delivery, they could be oxidized and have mineralogy dominated by silicates and diamond in their interiors. The reaction could produce CH4 at shallower depths and H2 at greater depths that could be degassed from the interior, causing the atmospheres of the converted carbon planets to be rich in reducing gases. Excess water after the reaction can be stored in dense silica polymorphs in the interiors of the converted carbon planets. Such conversion of mineralogy to diamond and silicates would decrease the density of carbon-rich planet, making the converted planets distinct from silicate planets in mass–radius relations for the 2–8 Earth mass range.

Thermoelasticity and stability of natural epidote at high pressure and high temperature: Implications for water transport during cold slab subduction

Epidote is a typical hydrous mineral in subduction zones. Here, we report a synchrotron-based single-crystal X-ray diffraction (XRD) study of natural epidote [Ca1.97Al2.15Fe0.84(SiO4)(Si2O7)O(OH)] under simultaneously high pressure-temperature (high P-T) conditions to ~17.7 ​GPa and 700 ​K. No phase transition occurs over this P-T range. Using the third-order Birch-Murnaghan equation of state (EoS), we fitted the pressure-volume-temperature (P-V-T) data and obtained the zero-pressure bulk modulus K0 ​= ​138(2) GPa, its pressure derivative K0' ​= ​3.0(3), the temperature derivative of the bulk modulus ((∂K/∂T)P ​= ​−0.004(1) GPa/K), and the thermal expansion coefficient at 300 ​K (α0 ​= ​3.8(5) ​× ​10−5 ​K−1), as the zero-pressure unit-cell volume V0 was fixed at 465.2(2) Å3 (obtained by a single-crystal XRD experiment at ambient conditions). This study reveals that the bulk moduli of epidote show nonlinear compositional dependence. By discussing the stabilization of epidote and comparing its density with those of other hydrous minerals, we find that epidote, as a significant water transporter in subduction zones, may maintain a metastable state to ~14 ​GPa along the coldest subducting slab geotherm and promote slab subduction into the upper mantle while favoring slab stagnation above the 410 ​km discontinuity. Furthermore, the water released from epidote near 410 ​km may potentially affect the properties of the 410 ​km seismic discontinuity.

Germanium iodide mediated synthesis of nanodiamonds from adamantane “seeds” under moderate high-pressure high-temperature conditions

There is an emerging demand for nanodiamonds with controlled structures or shapes for applications in biomedical imaging and sensing. Synthetic conditions proceeding at less harsh temperatures and pressures are considered crucial to control nanodiamond formation process. We report a germanium iodide (GeI4) mediated synthesis of nanodiamonds from diamondoid molecules and alkane hydrocarbon under moderate high-pressure high-temperature (m-HPHT) conditions. For the first time, GeI4 is used to generate nanodiamonds at 3.5 GPa and 500 °C, which is considerably lower than the conditions reported for common HPHT methods for nanodiamond synthesis. The strategy reported herein allows synthesizing nanodiamonds based on well-defined molecular precursors, which paves the way to a bottom-up diamond synthesis designed at a molecular level.

Carbide Formation in Refractory Mo15Nb20Re15Ta30W20 Alloy under a Combined High-Pressure and High-Temperature Condition.

In this work, the formation of carbide with the concertation of carbon at 0.1 at.% in refractory high-entropy alloy (RHEA) Mo15Nb20Re15Ta30W20 was studied under both ambient and high-pressure high-temperature conditions. The x-ray diffraction of dilute carbon (C)-doped RHEA under ambient pressure showed that the phases and lattice constant of RHEA were not influenced by the addition of 0.1 at.% C. In contrast, C-doped RHEA showed unexpected phase formation and transformation under combined high-pressure and high-temperature conditions by resistively employing the heated diamond anvil cell (DAC) technique. The new FCC_L12 phase appeared at 6 GPa and 809 °C and preserved the ambient temperature and pressure. High-pressure and high-temperature promoted the formation of carbides Ta3C and Nb3C, which are stable and may further improve the mechanical performance of the dilute C-doped alloy Mo15Nb20Re15Ta30W20.

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions.

The externally-heated diamond anvil cell (EHDAC) can be used to generate simultaneously high-pressure and high-temperature conditions found in Earth's and planetary interiors. Here we describe the design and fabrication of the EHDAC assemblies and accessories, including ring resistive heaters, thermal and electrical insulating layers, thermocouple placement, as well as the experimental protocol for preparing the EHDAC using these parts. The EHDAC can be routinely used to generate megabar pressures and up to 900 K temperatures in open air, and potentially higher temperatures up to ~1200 K with a protective atmosphere (i.e., Ar mixed with 1% H2). Compared with a laser-heating method for reaching temperatures typically >1100 K, external heating can be easily implemented and provide a more stable temperature at ≤900 K and less temperature gradients to the sample. We showcased the application of the EHDAC for synthesis of single crystal ice-VII and studied its single-crystal elastic properties using synchrotron-based X-ray diffraction and Brillouin scattering at simultaneously high-pressure high-temperature conditions.