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Managing black powder in sales gas transmission pipelines
Abstract
Black powder is regenerative, and is formed inside natural gas pipelines as a result of corrosion of the internal walls of the pipeline. More specifically, black powder forms through reactions of the pipeline steel with condensed water containing O2, H2S, and CO2. A synopsis of published literature including earlier findings; new field evidence showing the presence of excess moisture in the lines; various black powder management philosophies and methods; and the ongoing black powder research activities at the Saudi Aramco Research and Development Center are presented.
... Their findings concluded that the main sources of BP formation are pipe milling and air-drying of pipelines post hydrotesting. Microbial corrosions were found to be insignificant in BP formation (Sherik, 2016); H 2 S and CO 2 levels are always maintained at low concentrations in sales gas, thus, do not tend to be a major contributor to BP. Nevertheless, in the presence of water moisture, such gases can indeed cause corrosion Sherik and Davis, 2009). ...
... In light of such findings, BP mitigation and removal solutions were investigated (Al-Qabandi et al., 2015;Khan and Al-Shehhi, 2015;Powell et al., 2012;Sherik, 2016;Venkatadri and Brayden, 2015). The commonly adopted removal solutions involve the use of filters and cyclone separators. ...
... Installation of filters downstream of gas pipelines can protect pipeline instrumentation and customers. Different types of filter cartridges have been reported in (Khan and Al-Shehhi, 2015;Sherik, 2016;Triflieff and Wine, 2009). Cyclone separators are based on the principle of centrifugal force, whereby heavy solid contaminants precipitate in a collection hub at the bottom of the cyclone and the solid-free gas is exhausted from the top. ...
... Experience from world-wide operators indicates that black powder severely impacts pipelines reliability, operation and integrity leading to malfunctioning of equipment such as compressors, sensors, control valves and flanges. Most importantly, it contaminates the gas end customer fuel supply and increases the risk of associated H&SE events, (Sherik, 2007;Sherik et al., 2008;Azadi et al., 2012;Baldwin, 1998;Trabulsi, 2007;Tsochatzidis, 2008;Zhang et al., 2012;Dugstad and Sirnes, 2011). ...
... These variations have to be taken into consideration in the design and operation philosophy of plant upgrades and in new plants. Sherik et al. (Sherik et al., 2008) suggested several black powder prevention methods. For the new pipelines internal coatings, moisture control and good commissioning practices can offer better control on preventing black powder formation. ...
... Oxygen is considered as one of the key elements in internal corrosion of gas pipelines. Sherik et al. (Sherik et al., 2008) reported that the major reason for internal corrosion at Saudi Aramco pipeline network was condensed water containing O 2 , H 2 S and CO 2 with O 2 being the most critical element while the source was inefficient gas dehydration process in some treatment plants. They reported that moisture content measured in one of the sales gas plants was higher than maximum allowable by Aramco moisture in air specifications of 11.2 Â 10 À5 kg/m 3 . ...
Black powder is a global issue faced by almost all gas producing countries. Understanding characteristics and nature of black powder is required for successful pipeline operations and to assess root-cause of its formation. This paper is mainly divided into two parts. First part gives a synopsis of the global black powder experience and summarizes associated issues and challenges. Second part of the current study is dedicated to chemical characterization of black powder samples received from a sales gas pipeline and root-cause assessment of its formation in a gas processing plant in the Middle East. Elemental analysis of black powder samples show presence of mainly iron and sulfur with traces of various other elements. Further analysis shows presence of both iron sulfides and iron oxides in the network. Root-cause assessment measurements are made from three gas treating and dehydration units in a gas processing plant. Analysis of about 5 month's data indicated that the H2S levels in one of the trains were 3-4 times higher than the other two trains. Assessment analysis points to the possibility of black powder being generated in some processing units and in the sales gas pipeline.
... It can be attributed to corrosion of vessels, plant piping from upstream side by a combination of H 2 S, moisture and erosion of protective films. Sherik et al. (2008a) presented black powder management philosophies and provided an insight into the ongoing research at Saudi Aramco. They have discussed the black powder formation mechanism and showed that black powder can by formed by reactions of iron present in ferrous pipelines with condensed moisture containing O 2 , H 2 S and CO 2 . ...
... A research study by Zhu (Zhu) showed that iron oxides may be formed due to microbiologically induced corrosion (MIC) that results from either iron oxidizing bacteria (IOB) or acid producing bacteria (AOB). Sherik et al. (2008a) reported that the major reason for internal corrosion at Saudi Aramco pipeline network was condensed water containing O 2 , H 2 S and CO 2 with O 2 being the most critical element while the source was inefficient gas dehydration processes in some treatment plants. They reported that moisture content measured in one of the sales gas plants was higher than maximum allowable by Aramco moisture in air specifications of 7 lbs/mmscf. ...
... Purging of valve station at the entrance of the border metering station in Greece with gas after pigging (Tsochatzidis and Maroulis, 2007). Sherik et al. (2008a) presented several methods of black powder removal and prevention available to operators for mitigating the formation and managing the impact of black powder. Some of the removal methods presented include; mechanical and chemical cleaning, use of separators, filters and cyclon-filters. ...
Natural gas is extensively used in energy production, process industry and domestic applications across the globe. Black powder has been identified as a major operational problem faced by the gas industry today. A detailed literature review was carried out to report recent studies on black powder phenomenon in the gas pipelines. Focus has been on reporting research studies conducted at industrial level. Presence of black powder causes product contamination, erosion, clogging, fouling and flow reduction in the pipelines. Sitting black powder may cause operational problems, but its movement with gas flow poses even bigger challenge. A substantial amount of work has been reported on characterization and removal of black powder. The current review highlights research gaps and recommends quantifying effects of several operational and geometric parameters to better understand and manage black powder in gas pipelines.
... Evidence collected so far, points to the fact that BP particles are generated when hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ) or oxygen (O 2 ) are present in the gas or by bacterial corrosion of the internal walls of the pipelines (Sherik, 2007(Sherik, , 2008Sherik et al., 2008;Cattanach et al., 2010). BP is known to contain primarily 81% iron oxides (Godoy et al., 2005;Tsochatzidis and Maroulis, 2007) and, in other cases, a mixture of iron oxides and iron sulfides (Baldwin, 1998;Godoy et al., 2005;Sherik, 2007;Tsochatzidis and Maroulis, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). ...
... Evidence collected so far, points to the fact that BP particles are generated when hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ) or oxygen (O 2 ) are present in the gas or by bacterial corrosion of the internal walls of the pipelines (Sherik, 2007(Sherik, , 2008Sherik et al., 2008;Cattanach et al., 2010). BP is known to contain primarily 81% iron oxides (Godoy et al., 2005;Tsochatzidis and Maroulis, 2007) and, in other cases, a mixture of iron oxides and iron sulfides (Baldwin, 1998;Godoy et al., 2005;Sherik, 2007;Tsochatzidis and Maroulis, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). ...
Black powder (BP) is a universal problem that occurs in sales gas pipelines all over the world. It can cause costly problems for the pipeline operation, instruments and processing industries. The main objective of the present study is to develop a novel methodology for tracking the concentration of BP within the gas transmission network taking into account the deposition of solid particles. The mathematical model is based on the 1D flow and dusty gas assumptions. The analytical solution of a one-dimensional scalar advection/reaction equation is used to track the concentration of BP within the whole gas network. The reaction term in the advection/reaction equation represents the concentration changes due to the deposition of solid particles. Different flow conditions and particle diameters are considered. The approach is tested by considering particle-laden flow in pipe segments with and without junctions which were simulated using CFD based on the discrete particle model (DPM). The 1D approach is validated with the CFD simulation for single pipe geometry. The results for the tree-shaped network shows that the sub-microns particle can be transported throughout tree shaped network, while the larger particles of diameters dp > 1 (µm) are likely to settle rapidly near to the source, forming stratified beds. The obtained results from the present study are of significant practical interest, due to the lack of available data on BP dispersion in natural gas networks that have been reported in the literature to date. Mapping of BP distribution within the gas transmission network provides essential data that can help to identify the locations of where the filters/cyclone separators can be installed within the gas transmission network. This leads to better options for efficiently removing and managing the BP in the gas network to protect the downstream equipment
... Evidence collected so far, points to the fact that BP particles are generated when hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ) or oxygen (O 2 ) are present in the gas or by bacterial corrosion of the internal walls of the pipelines (Sherik, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). BP is known to contain primarily 81% iron oxides (Godoy et al., 2005;Tsochatzidis and Maroulis, 2007) and, in other cases, a mixture of iron oxides and iron sulfides (Baldwin, 1998;Godoy, 2005;Sherik, 2007;Tsochatzidis and Maroulis, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). ...
... Evidence collected so far, points to the fact that BP particles are generated when hydrogen sulfide (H 2 S), carbon dioxide (CO 2 ) or oxygen (O 2 ) are present in the gas or by bacterial corrosion of the internal walls of the pipelines (Sherik, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). BP is known to contain primarily 81% iron oxides (Godoy et al., 2005;Tsochatzidis and Maroulis, 2007) and, in other cases, a mixture of iron oxides and iron sulfides (Baldwin, 1998;Godoy, 2005;Sherik, 2007;Tsochatzidis and Maroulis, 2007;Sherik, 2008;Sherik et al., 2008;Cattanach et al., 2010). ...
Black Powder (BP) is a universal issue in sales gas transmission pipelines. It can cause serious problems in pipelines operations and instruments and contaminate customer supply. The objective of the present study is to develop a novel methodology for tracking the dispersion of Black Powder within gas transmission pipelines using a 1D approach based on the dusty gas assumption and the usage of analytical solutions of one-dimensional scalar advection/reaction equation. The study takes into account the deposition of Black Powder particles under different flow conditions, different particle diameters and different surface roughness. The proposed approach is applied to particle-laden flow in pipe segments with and without junctions and contrasted against CFD simulations based on the discrete particle model (DPM). The results shows that the finer particle with a particle diameters dp < 1 (μm) can be transported easily to the downstream of the tree shaped network, while the larger particles dp > 1 (μm) are likely to settle rapidly near to the source location where Black Powder is generated and consequently forming beds. It is shown also that surface roughness increases the deposition rate of small particles dp ≤ 1 (μm) controlled by the Brownian forces. However, the deposition of larger particles in the inertial regime is not affected by the change in the surface roughness. These reported results are of significant practical interest, due to the lack of available data of Black Powder concentration in natural gas networks that have been reported in the literature to date
... However, under certain working conditions in gas transmission networks, corrosion might cause the generation of solid particles. These with a general composition of iron oxides and sulfides, is what is commonly known as Black Powder, and form and propagate randomly inside the gas piping network [5,6]. The ideal, but very difficult to achieve in practice, safety procedure consists in eliminating the sources of Black Powder completely. ...
... The ideal, but very difficult to achieve in practice, safety procedure consists in eliminating the sources of Black Powder completely. In fact, experience shows that attempts to eliminate the formation of Black Powder are still not satisfactory due to the complexity of the task and the ever present industrial constraints [6]. Consequently, Black Powder must be controlled and monitored to minimize its effects on the equipment of gas producers and consumers. ...
In this study, CFD is used to investigate an important local phenomenon when populations of particles are split within junctions of gas piping networks. The particle-laden turbulent flow is studied using the k-ε turbulence model and the Discrete Phase Model DPM. The phase split is obtained for different working conditions including the effect of the particle diameter, the angle and the orientation of the branch. Particular attention is given to the effects of the flow rate of the gaseous phase when imposed at the outlets of the junction to replicate the flow control in real installations using valves.
The fluid flow split yields different flow rate fractions in the two sides of the junctions which generates complex flow topologies affecting the solids split remarkably. The straight prolongation of the main pipe is called the main while the other side of the junction is the branch with different angles and orientations. Under extreme cases of fluid flow split, vortices form at the entrance of the main and alter the trend of solids split remarkably. In addition, large particles undergo a slight settling affecting their spatial distribution upstream of the junction which adds a degree of complexity to the solids split.
... Indeed, gas piping networks are designed for the transport of clean gas and junctions of different types can be used for the split between branches to transport gas to different destinations from the same source. Under the effects of corrosion, particles of iron oxides and iron sulfides, called Black Powder, form and propagate randomly inside the gas piping network [4,5]. The ideal, but very difficult, safety procedure consists in eliminating the sources of Black Powder completely. ...
... Size distribution at the outlets of the junction for poly-dispersed particles (Injection 1). defined in Eq. (5). The vertical component of the drag force represents the maximum based on local variables upstream and underneath the junction. ...
The present study consists in simulating turbulent gas–particle flows through pipe junctions under different geometrical
and flow conditions. The purpose is to study the effects of the particles' size and orientation of the pipes
with different degrees of asymmetry at junctions on phase split. Solid particles can be present in gas transmission
networks as contaminants in the form of Black Powder to be eliminated. The simulation based on the standard
k-ε turbulence model and the Discrete Phase Model (DPM) showed that the solid phase split can be considered
to follow the air flow split closely for Stokes numbers small enough than unity (St = 0.2). While for intermediate
Stokes numbers (St = 1) and slightly higher than unity (St = 5), the particles gain some independence from the
gaseous phase and for the later, the pipe orientation plays a significant role. Effects of the shape of the particles
and their initial positions at the inlet are also considered.
... The pressure inside the natural gas pipelines will decrease, and this will lead to higher resistance for compressors. The third impact of BP is that it affects the natural gas network monitoring equipment such as flow meters, and this results in misleading network information [7], [8]. ...
Natural gas transmission pipeline networks are facing serious issues related to the solid particles deposition that is called black powder (BP). The creation of BP inside natural gas pipeline is not completely understood, but it mainly results from the pipelines inner walls corrosion, which is a complex chemical reaction between the natural gas and pipelines. Moreover, the exact BP generation time, amount, and location are still vague. This work aims to reduce the effect of BP by estimating BP concentrations in natural gas networks. This will significantly help natural gas pipeline networks operators to plan more effective maintenance schedules. This work takes into account the industrial need for simple, fast, and accurate techniques for estimating BP concentration in natural gas pipeline networks. The proposed BP estimation technique is based on a lookup table (LT) which is constructed from a one-dimensional model of BP deposition and transport. This technique eliminates the need for extensive computational efforts and long estimation times that are necessary for other optimization-based BP estimation techniques. The proposed LT-based BP estimation technique is validated and compared to other BP estimation techniques using simulation studies. The results of the proposed BP estimation technique show that it is promising and has potentials for application in existing and future natural gas networks.
... Further, up to 50% of black powder contamination can be at 5 microns or less; 30% of it can be at 1 micron or less [15]. Sherik reported 50% of contamination of gas pipelines in Abu Dhabi was between 3 and 5 µm, while only 5% was in the 50 to 100 µm range [16]. Moreover, Mueller analyzed wet and dry samples in laboratory and the experimental results show that 81.6% of black powder samples had a size less than 1 µm [17]. ...
... Especially in gas pipelines, black powder is the most common solid contaminant through the world 11 . Its composition differs from different situations and can be considered as the mixture of either iron sulfides, carbonates, hydroxides or oxides which probably came from scales, corrosion products, rust, salts or mill-scale 12,13 . There are two basic ways of scale solids present in pipelines: suspending in aqueous solution or adhering to the pipe surface 14 . ...
... Especially in gas pipelines, black powder is the most common solid contaminant through the world 11 . Its composition differs from different situations and can be considered as the mixture of either iron sulfides, carbonates, hydroxides or oxides which probably came from scales, corrosion products, rust, salts or mill-scale 12,13 . There are two basic ways of scale solids present in pipelines: suspending in aqueous solution or adhering to the pipe surface 14 . ...
a review of the current NDT technologies used to quantify and identify the scale deposits that occur in transmission pipelines
... It also represents health and environmental issues. More importantly, it increases the risk of associated HS&E events, [1][2][3][4][5][6][7][8]. UAE have come across this contamination problem, [4][5][6][7][9][10][11][12][13]. ...
Black powder (BP) is a typical contaminant usually found in sales gas pipelines. Its presence may cause major operational and maintenance issues including blockage of sensors and filters, erosion of pipeline bends and compromise the sales gas quality. There has been little known about its composition and sources of formation in the gas pipelines. Understanding its characteristics is considered crucial for appropriate mitigation planning and execution of smooth pipelines operations. Black powder samples collected from sales gas pipelines network of a Middle Eastern gas company are analyzed using scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray diffraction (XRD) methods for surface analysis and phase identification of the crystalline material. These analyses revealed variation in size distribution and shape of the BP samples. Likewise, most of the BP particles were found agglomerated. Elemental analyses of the sample have shown presence of iron as the most abundant element after sulfur. XRD patterns can be indexed with both iron oxides and sulfides suggesting presence of moisture and hydrogen sulfide in the gas.
... Sometimes, such sub-micron sized particles accumulate forming larger particles. [4][5][6][7][8][9]. ...
The process industry is concerned with the processing of crude resources into other products.
Such crudes consist of multiphase components that introduce major challenges to the
operators; hence the need for efficient instrumentations that address such challenges is highly
desirable. One major need is an early deposit detection system that detects deposit before it
builds-up in a pipeline or equipment to prevent any possible hazard. Another critical
requirement is the need to continuously monitor the flow and deduce the flow rate of every
individual phase in order to study and analyse the produced product. Hence, in order to
ensure safety, increase profits, optimize production and ensure production quality, the
multiphase flow must be adequately monitored and controlled. This thesis demonstrated the
efficiency of novel ECT algorithms for early deposit detection and multiphase flow
measurement in order to measure the flow rate of all separate phases. This thesis focuses on
developments in ECT image reconstruction specifically the inverse solutions and is divided
into three main studies where they all build up to complete each other. In the first study, ECT
is used for the first time with a narrowband pass filter to focus on targeted locations in a pipe
where dielectric contaminants are expected to deposit in order to enhance the resolution of
the produced images. The experimental results showed that different deposit regimes and
accumulated fine deposits could be detected with high resolution. The second study allowed a
better understanding of how conductive material could be imaged using a conventional ECT
device and how state of the art algorithms such as iterative total variation regularisation
method and the level set method could enhance this application. Also, absolute ECT imaging
is presented for the first time where the level set algorithm uses only one set of ECT
measurement data. This study gives a novel solution for detecting conductive deposits as well
as paves the way to use the new level set algorithm for multiphase flow measurement. In the
third study, the novel narrowband level set algorithm was modified to image multiphase
media in order to correctly determine the number, location and concentration of the present
phases. The innovative absolute ECT imaging using level set method is tested with high
contrast and low contrast multiphase data, which adds more to the challenge.
... Jin et al. (2015) conducted an experimental and modeling study on the deposition of barite in onedimensional tube to replicate problems occurring when seawater is injected in oil reservoir to maintain their pressure. In this study, focus will be on solid particles of iron oxides and iron sulfides, called Black Powder, that form, deposit or get transported inside natural gas transportation piping network which usually consist of long horizontal pipes with limited vertical segments (Baldwin, 2000;Sherik, 2007). It is therefore important to predict their deposition rate accurately since it affects their transport and dispersion in such piping systems. ...
The deposition of Black Powder particles in gas pipelines is a critical industrial problem. Gas-solid flow in a pipe is simulated using the Reynolds Stress Model (RSM) and the Discrete Phase Model (DPM). In this study, 3D meshes for pipes with different orientations are considered. Vertical orientations were, also, considered although they are not as common as the horizontal pipeline in the gas industry. Efforts were made to predict an accurate turbulent flow field as a requirement for successful simulation of particle deposition velocity. A fine mesh was used to resolve the viscous sublayer and DNS or experimental profiles of the fluctuating velocities were imposed to minimize the inaccurate prediction of the RSM model to determine the fluctuating velocity needed for the particle trajectories. Black Powder particles, in the range 1–50 μm, were injected in the computational domain as mono-dispersed and poly-dispersed size distributions respectively. The spatial distribution of the particles, injected at the inlet of the three-dimensional pipe, was randomly varied with time to replicate realistic distributions.
... In transmission and distribution lines in which the gas has been treated to remove H 2 S, presence of H 2 S in amounts greater than the maximum allowable likely indicates microbes, although it could also mean the failure of a treatment plant [3,4]. ...
Black Powder has identified as a significant problem in all areas of hydrocarbon production facilities and transit or export lines. The phrase ‘Black Powder’ in the oil industry used to describe a contaminant found from wellhead, Gathering Centers and gas export lines. The constituents of black powder are known to adversely affect the efficiency, integrity and reliability of oil and gas production, refining and transportation. Its combines of corrosion material such as Iron sulfide, Iron oxide, Wax, Asphaltene, silt and sands. Its vary from one location to another within the process of the oil and gas production. Its presence in all areas of upstream, midstream and downstream oil and gas production. It's affecting the flow assurance and quality of performance of the facilities from compressors, vessels, tanks, sensors and pipelines and finally impacting the refinery efficiency. Its major problem start to be present recently in oil industry which many different operators have different misunderstanding to overcome these phenomena of the black powder. The paper will be to look at best strategy and solution success to mitigate the problem of the black powder in Kuwait Oil Company from west Kuwait operation facilities to Refinery. It will highlight also roots cause, Impact and prevention plan. It will show how it help reduce gas flaring, minimization facility shutdown, reduce Flowlines leaks, and optimize chemicals consumption in operation facilities which lead to cost optimization.
... Indeed, gas piping networks are designed for the transport of clean gas and junctions of different types can be used for the split between branches to transport gas to different destinations from the same source. Under the effects of corrosion, particles of iron oxides and iron sulfides called Black Powder form and propagate randomly inside the gas piping network [3,4]. Eliminating the sources of Black Powder is the perfect solution by investigating the appropriate operating conditions and material characteristics of the pipes. ...
The present study is a part of an industrial research project and consists in simulating a gas-particle flow through junctions under different geometrical and flow conditions. The purpose is to study the effects of the size of particles, the angles of the junction and the flow rate on the flow split. The particles are usually considered as products to transport, such as in pneumatic conveying, where phase split, if necessary, is done in symmetrical Y-junctions to avoid mal-distribution issues. Thus, asymmetrical junctions were, usually, avoided in transportation networks. However, it appeared that the particles can manifest within networks for transportation of gases as contaminants to be eliminated. A typical example is that of Black Powder in gas pipelines in the oil industry. In such piping networks, different types of junctions can be used and it is worth understanding the behavior of particles for unsymmetrical configurations as well. The numerical simulation combines the k-ε and the Discrete Phase DPM turbulence and multiphase models, respectively. Relatively, good agreement in the results between the model and the experiments was obtained. The simulations were extended to Black Powder particles and the corresponding results showed interesting features for different Stokes numbers. The simulation results showed that, for Stokes numbers much smaller than unity (St≤0.2), the solids phase split can be considered to follow the air flow split closely. For intermediate Stokes numbers (St≈1), the particles gain some independence from the gaseous phase. For Stokes numbers slightly higher than unity (St≥5), the orientation plays an important role.
... Black powder is a term used to describe the grayish material generated in sales gas pipelines mainly as a result of internal corrosion of the pipeline wall. 1 It occurs in a variety of ©2011 by NACE International. Requests for permission to publish this manuscript in any form, in part or in whole, must be in writing to NACE International, Publications Division, 1440 South Creek Drive, Houston, Texas 77084. ...
Black powder formation is an oxidative corrosion process that over time can cause operational problems as the solids collect within the system. There is a net weight gain within the system as molecular oxygen becomes incorporated as part of the solid materials. A novel quartz crystal microbalance (QCM) test apparatus has been developed to determine the effectiveness of various corrosion inhibitors to prevent black powder formation in sales gas pipelines. The QCM measures minute changes in frequency of a quartz crystal with weight gain/loss. For our test apparatus, the QCM crystal was coated with iron where small increases in mass due to oxidation of the iron layer are recorded as a drop in frequency. Using the Sauerbrey equation, the drop in frequency observed during corrosion testing can be converted to a corrosion rate. Several inhibitor chemistries were tested using the QCM apparatus. In this study it was found that a new oil-soluble corrosion inhibitor is the most effective for preventing black powder formation under the sales gas conditions.
A new method for determining the mass change due to oxidation of iron and the associated corrosion rate under sales gas conditions using the quartz crystal microbalance (QCM) is presented. The method involves four steps: 1) determining the overall frequency change of QCM, 2) subtracting the frequency change due to water film formation from the total frequency change, 3) calculating the resulting mass change of the QCM, and 4) determining the corresponding corrosion rates. In this paper, QCM is used to determine the effects of critical system parameters such as ΔT/relative humidity, oxygen partial pressure, and carbon dioxide partial pressure on the QCM weight gains and the corresponding corrosion rates. The relative humidity (RH) of the gas system and temperature difference (ΔT) between the gas and the metal surface play a critical role in determining the iron oxide formation and associated corrosion rates. The RH determines the thickness of the water condensation layer on the metal surface that in turn controls the corrosion rate. Some uncertainty with maintaining the water film thickness was observed. The results show that there is an increase in corrosion rate with increasing oxygen partial pressure. For a system with oxygen partial pressure of 0.2 psia, carbon dioxide was shown to have little effect on the oxide formation and corrosion rate.
This paper reviews some of the Saudi Aramco R&D Projects for increasing the asset life expectancy of its production facilities. The ultimate objective is to deliver innovative solutions to address actual or anticipated problems encountered by operations. The Research and Development Center in Saudi Aramco has developed a generic delivery model consisting, for each project, of the identification of the following four main components: business need, value created, internal competencies and partners to provide solutions in a timely manner
The portfolio for the Upstream R&D Program for the production facilities is composed of several projects:
The Crude Oil Separation project to improve the separation of the production into oil, gas and water phases.
The Emulsion Mitigation project to handle specific problems related to emulsion from the near wellbore to the separation vessels included.
The Water Systems project built with a holistic approach, to handle produced and injected water, and associated phenomena such as bacterial control and corrosion.
The Scale Mitigation project to prevent and mitigate scale in oil and gas wells, for better injectivity and productivity.
The Pipeline Integrity project, which includes a variety of issues such as sulfur deposition and blister control.
The Black Powder Management project, a multi-disciplinary project to address this specific issue caused by corrosion for sales gas pipelines.
This paper will summarize the goals and deliverables of these projects. Further potential R&D projects for Production or Midstream related issues are also listed.
Black powder formation is an oxidative corrosion process that over time can cause operational problems as the solids collect within the system. There is a net weight gain within the system as molecular oxygen becomes incorporated as part of the solid materials. A novel quartz crystal microbalance (QCM) test apparatus has been developed to determine the effectiveness of various corrosion inhibitors to prevent black powder formation in sales gas pipelines. The QCM measures minute changes in frequency of a quartz crystal with weight gain/loss. For our test apparatus, the QCM crystal was coated with iron where small increases in mass due to oxidation of the iron layer were recorded as a drop in frequency. Using the Sauerbrey equation, the drop in frequency observed during corrosion testing can be converted to a corrosion rate. Several inhibitor chemistries were tested using the QCM apparatus. In this study it was found that a new oil-soluble corrosion inhibitor is the most effective for preventing black powder formation under the sales gas conditions.
The present work was carried out to assess the (210)Pb content in "black-powder" found in pigging operations on gas pipelines in Brazil, in particular, on the Campos Basin gas pipeline. Additionally, the chemical composition of such deposits was determined and an eventual correlation with (210)Pb concentration evaluated. Typical "black-powder" generated in the natural gas pipeline from Campos Basin oilfield contains mainly iron oxide ( approximately 81%) and residual organic matter ( approximately 9%). The (210)Pb content ranges from 4.9 to 0.04k Bqkg(-1) and seems to be inversely correlated with the distance to the platforms. On the other hand, (226)Ra concentration is higher on the pipeline branch between the platform and the onshore installations. (228)Ra was only observed in few samples, in particular, in the samples with the highest (226)Ra content.
Konstantinos E. Maroulis DEPA SA Athens Effective removal of black powder from a gas transmission system often requires a combination of methods. Removing such particulates is a multistep process requiring a comprehensive understanding of the nature of the problem. Different tools may be effective in some instances but not in others. This article examines Greek Public Gas Corp. SA's (DEPA's) experience in fighting black powder in its system, focused on its determining which technique provided the most efficient and cost-effective method of powder removal. Included in this examination are the different sorts of pigs, filters, and separators DEPA used in attempting to address the problem, with the effectiveness and shortcomings of each assessed.
Pipeline internal debris can manifest itself in a number of forms. The specific form in any given situation is typically a function of the transported fluid, the metallurgy of the pipe, and the conditions at which the pipeline operates. Generally, debris formation is typically a result of a chemical reaction between the transported fluid and the pipe alloy, some change in the fluid conditions between pipeline inlet and outlet, or possibly both. A discussion covers common debris types and the most common mechanism associated with debris formation; the combined use of denser, more viscous fluids and effective cleaning pigs to satisfy requirements of overcoming the issues impeding effective debris transport; pipeline geometry and profile; debris quantity estimation; non-uniform debris distribution; and cleaning train configuration.
Black powder can have a serious impact on customer complaints and pipeline operations, i.e., instrument scraping delays and reduced in-line inspection accuracy, and control valve and pipe erosion. Without fundamental knowledge of source and formation mechanisms for black powder, the question within Saudi Aramco of whether black powder is regenerative or non-regenerative cannot be resolved. The experimental program and analysis of results conducted to determine composition, source, and formation mechanisms of black powder in Sales Gas pipelines were presented. None of the analyzed black powder samples showed hematite-Fe2O3 or wuestite-FeO that are typical iron oxide phases found in mill scale. Black Gas in Sales Gas transmission pipelines was mainly composed of iron hydroxides and an iron oxide. Internal corrosion of the internal walls of the Sales Gas lines was the source for black powder.
Recent research into black powder problems experienced by natural-gas transmission pipelines indicates steps that can be taken to control the material in gas pipelines, gathering systems, and storage facilities. Black powder (the common term for various forms of iron sulfide mixed with contaminants) is the least understood but most prominent contaminant in natural-gas pipelines and compression equipment in pipeline, refinery, gathering, and storage applications. One of two mechanisms creates iron sulfides: chemical reaction of constituents present in the pipeline, usually hydrogen sulfide, or microbial assimilation of chemical constituents in the pipe and the production of both iron sulfides and pipe-wall pitting. The paper describes the sources of black powder, filtering, gas quality, testing, removal, handling, and disposal.