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ABSTRACT For the past two years a large Canadian pipeline company has installed magnesium anodes powered by solar panels to obtain levels of protection in high resistivity environments. Pipelines are remote from AC power sources, making conventional impressed systems cost prohibitive. Magnesium anodes alone are also cost prohibitive due to the quantities required in high resistivity environments. Solar powered magnesium anodes have shown to be both a technically and economically sound alternative to conventional methods of supplying cathodic protection current to the company's pipelines in high soil resistivity environments. INTRODUCTION TransCanada Pipeline is a Canadian transmission company that transports natural gas from the Canadian Western Basin to the eastern market. The company owns and operates approximately 40,000 kms (24, 800 mi.) of high-pressure transmission pipeline. Geographically the company's system stretches from the province of Alberta in the west to the province of Quebec in the east. Pipeline systems consist of a gathering system within Alberta, and multiple transmission lines that run adjacent to the 49 th parallel, and loop around the Great Lakes. Looping around the Great Lakes forces the pipeline right of way through Northern Ontario, see Figure 1.TransCanada Mainline System. The 1998 Thunder Bay Region Corrosion Remedial Program focussed on installations on the "Thunder Bay Shortcut", while the 1999 Thunder Bay Region Corrosion Remedial Program consisted of work in the western part of the region. See Figures 2 and 3 for detailed locations. Environmental conditions in Northern Ontario are often detrimental to pipeline construction and providing cathodic protection. Terrain conditions typically consist of bedrock less than 1 m (3.3 ft) from grade, sand, swamp, water bodies, steep rises, and undulating right of ways. Much of the right of way is remote, making access and the availability of conventional power sources (AC power lines) major issues. PAST PRACTICES The operator subscribes to exceeding the "-0.850 volts polarized potential" criteria as per RP0169-96 (with respect to the CHfCuSO4 reference cell) or 150 mV of depolarization for Northern Ontario. The company criteria of 150 mV of polarization is 50 mV greater than the NACE International 100 mV criteria due to earlier inaccuracies of survey and interruption equipment. Synchronized "OFF" potential surveys in earlier years were very inaccurate due to timing devices within the current interrupters and lack of timing devices in the data collectors. Today, these problems have been resolved and a re- evaluation of this criterion may take place. Areas failing to meet either criterion are addressed with additional cathodic protection. Areas below protection are typically 50 to 200 metres (164 to 656 ft) in length and are discrete. In the past, the operator has tried a variety of options to address sub-criterion potentials on their pipelines. Sacrificial magnesium anodes where tried in the past with mixed results. Installations were often costly due to the quantity of sacrificial anodes required to deliver the cathodic protection current in high resistivity soils. Conventional impressed current systems have also been installed in remote areas. Installations of 3 to 5 km (1.86 to 3.1 mi.) and greater of either AC or DC poleline were common practice. Cathodic protection was delivered to the discrete, unprotected areas, but at approximately $15 000 / km (CDN$) ($9,300 / mi.) to install poles and overhead cables, this option becomes cost prohibitive. Wind generators as AC sources have also been used and for the most part failed due to the lack of consistent wind. Thermoelectric Generators (TEG) have also been installe
- North America > Canada > Ontario (1.00)
- North America > Canada > Alberta (0.89)
INTRODUCTION ABSTRACT Polypropylene (PP) and PVDF lined pipe experienced frequent failures in spent (60-78%) sulfuric acid after about seven to ten years in service. The failures were due to exceeding the design temperature when mixing 98% acid where high temperature is generated which then created thermal stress in the liner and bolted flared joints and developed cracks and product leaks. The PP was replaced by Polytetrafluoroethylene (PTFE) lined pipe using proper bolting torque. PTFE has been in service for more than 7 years without any failure. Plastics are widely used in industries, especially petrochemical plants due to their good chemical resistance to most of the aggressive chemical products. It is important during the design stage to consider all possible operational cases that may occurred during operation in the field such as changes in the temperature, concentration and other process parameters. This study helps in reducing failure and personnel injury specially when dealing with hazardous chemicals such as acids or caustic. For example, if carbon steel material was selected for 98% Sulfuric acid but there is a possibility of getting diluted acid into the system in the future. Then it is beneficial to consider this possible change and use better material such as alloy steels or lined pipe in order to prevent failures and injuries. Evaluation of the proper material selection in at the design stage may cost some money but in the long term, it pays back by reducing failures and frequent replacement. Therefore, process and material engineers should work together during the design stages in order to select the proper material that gives the design life without failures. The common plastic or plastic lined carbon steel materials used in industries are: ~ 1. Polyethylene (PE) - This material can be joined by thermal welding. It is widely used up to approximately 60°C especially for water service application. It is attacked by strong oxidants and is susceptible to environmental Stress Cracking (ESC) by some inorganic (48% hydrofluoric acid) and organic chemicals (notably detergents, wetting agents, alcohol, ketones, aldehydes, and organic acids). Chlorinated solvents and strong oxidants are to be avoided. 2. Polypropylene (PP) - This material is closely related to PE; they are both members of polyolefins group, composed only of carbon and hydrogen, its maximum temperature is around 107 °C and has melting point of 166°C. PP is stronger and somewhat more chemical resistance than (PE). However, it is susceptible to ESC in hot brine solutions and in 98% sulfuric acid. 3. Polyvinylchloride (PVC) - This material is very popular for water use, particularly in the presence of chlorine or other oxidants. Chlorinated PVC (CPVC) is used for hot-water services. Both PVC & CPVC have excellent resistance to both acids and alkalis at low concentration, but their solvent resistance is very limited. 4. Polyvinylidene Chloride (PVDC) - has improved strength, hardness, and chemical resistance, especially to organic solvents, mineral acids, and oxidants. 5. Fluorocarbons - These are the most versatile and important group of plastics for process industries. They have excellent corrosion resistance to almost all chemicals. Polytetrafluoroethylene (PTFE) provides adequate heat stability up to 260°C. Fluorinated ethylene propylene (FEP), Chlorotrifluoroethylene (CTFE), Polyvinylfluoride (PVF), Polyvinylidene fluoride (PVDF), Ethylene Chlorotrifluoroethylene (ECTFE) and Perfluoroalkoxy (PFA), are types of fluorocarbons which have different properties and uses. Fluoroplastics have a low coefficient of friction, especially the fluorinated resins, giving them unique non-adhesive
- Well Drilling > Drilling Fluids and Materials > Drilling fluid selection and formulation (chemistry, properties) (0.55)
- Management > Professionalism, Training, and Education > Communities of practice (0.51)
- Data Science & Engineering Analytics > Information Management and Systems > Knowledge management (0.51)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Corrosion inhibition and management (including H2S and CO2) (0.49)
ABSTRACT New information is emerging every day. Every day we each learn many new things, some valuable and some not so valuable. Some of this knowledge is valuable only to ourselves, but much of it is valuable to the world at large. In the corrosion field, practitioners are learning new things every day. Knowledge developed in the research laboratory spreads into the corrosion community through publication. The vast majority of the new knowledge, however, is based on experience and remains in the mind of the practitioner. This experienced-based knowledge is every bit as valuable to the practitioner's company, and the corrosion community as a whole, as the laboratory-based knowledge developed by the researcher. This paper will discuss the use of computer-based communications technology to tap into the experienced-based knowledge in the corrosion community and preserve it in a manner that makes it available to others in the practitioner's company, and to the corrosion community as a whole. INTRODUCTION The knowledge management industry classifies knowledge into two categories: explicit and tacit. Explicit knowledge is that which is easily communicated in terms of words and numbers, chemical formulas, or other general sets of rules. 1 Some examples of explicit knowledge in the corrosion community include the basic corrosion reactions of iron in water, the reactions by which sulfate reducing bacteria cause pitting, and the science of cathodic protection. Numerous publications are available that clearly describe the science involved. This kind of information is readily available from many sources, to anyone looking for it. Tacit knowledge, on the other hand, is much less easily formalized. It is largely in the possession of individuals, and is based on experience. Tacit knowledge is very personal. The individual in possession of the knowledge may not be able to express it, verbally or in written form, making it very difficult to communicate to others. 5. Tacit knowledge may be written down, but is typically in a form not readily usable by another person. By and large, however, tacit knowledge exists primarily in the mind of the practitioner. Much is based on the individual's experience in a specific field. In the case of corrosion science and its practical application, many individuals with large amounts of tacit knowledge in the field bear the title of NACE Fellow. When an experienced practitioner in the corrosion field, or any other field, retires from practice, the tacit knowledge that he has accumulated over a lifetime of work retires with him. Corporations are now recognizing that this tacit knowledge is a very valuable asset, and are searching for new ways to capture it and turn it into explicit knowledge that can be easily accessed by others in the corporation. G This paper will address the use of computer communications technology to capture this tacit knowledge hidden within corporations and the corrosion industry as a whole and convert it to explicit knowledge. LIST SERVERS A list server is an email-based system that allows diverse groups of people to communicate easily. It s tarts by establishing the list on a host computer and having members join. Once the members have joined, any message that is sent to the list server computer is automatically rebroadcast to all members of the list. This approach easily allows group communications, without the necessity of knowing which specific individual has the knowledge being sought. The simple fact that a question was answered in this manner does not convert the tacit knowledge possessed by one individual to explicit knowledge. It only results in two people having that bit of tacit knowledge. In o
- North America > United States > Louisiana (0.25)
- Asia > Middle East > Israel > Mediterranean Sea (0.25)
- North America > United States > Texas > Harris County > Houston (0.17)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Materials and corrosion (0.69)
- Well Completion > Well Integrity > Subsurface corrosion (tubing, casing, completion equipment, conductor) (0.55)
- Data Science & Engineering Analytics > Information Management and Systems > Knowledge management (0.54)
- Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (0.49)
ABSTRACT Corrosion is one of the great causes of accident and economic losses in petroleum and petrochemical industries. Thus, new materials, inhibitors and monitoring techniques are constantly under development in order to improve corrosion prevention and plant reliability. The last years have shown the great importance of Monitoring Techniques applied process industries. However, corrosion monitoring alone doesn't assure the control of corrosion process. Corrosion control in the industrial field can be quite complex since their domain is itself complex. It involves multidisciplinary knowledge and continuous actions from different agents. Knowledge Based Systems or Expert Systems developed trying to simulate the human expert intelligent behavior in the task of solving a specific problem are shown its importance in this scenario. This paper presents an overview on knowledge-based systems development and its interaction with industrial environment as well makes an approach to computer tools that facilitate their development, installation and maintenance. INTRODUCTION Corrosion costs 3 to 4% of Gross National Product in a Developed Country. Corrosion related failures constitute over 25% of failures experienced in the oil and gas industry. Existing technology could save up to thirty three percent of these costs 1. Corrosion Control in oil and gas, transportation and energy generation industry is a complex and time-consuming task. It depends on the continuous analysis of a great number of variables by corrosion experts and the prompt correction by plant operators. Modern technologies for corrosion measurement are allowing more data on the corrosion process and shorter periods of sampling. Corrosion process can be defined more precisely throughout these new methods, but large amount of data is added to database from which analysis must be performed. Monitoring and corrosion control naturally relies on Computer Science Technology to process the great amount of data required in this kind of industry. However, Computer Science help for Corrosion Monitoring is not restricted to data processing. It can also be used to save and increase the availability of an article with much more value: knowledge. Expert Systems (ES) can be used to reproduce human knowledge in computer systems. The most commonly used ES systems are based on rules that model the reasoning of the human expert. With such systems, knowledge is safely stored and made available in several plants at the same time, 24 hours a day, 7 days a week. Despite ES can provide an effective corrosion control in process plants 2 3, they are not very popular. Due to difficult to its development like knowledge transfer to system, long term required by system development and their high cost, few systems applied to corrosion monitoring and control have been conclude and are operating 4. ES development technology, its integration with plant data system and interaction with the different teams involved with corrosion control are described, based on four system developed 2,3.4 Technology applied to ES development as here described includes tolls like the BLOCK ES DEVELOPER SYSTEM. This tool allows the development of an ES in a shorter term, with lower cost and facilitating the knowledge acquisition and transfer to the system. CORROSION MONITORING Corrosion in process plant is normally characterized by a great number of variables involved, many of them presenting a high degree of interdependency with operational parameters. For this reason, corrosion monitoring must deal with many data, acquired from corrosion measurement probes, process plant instrumentation and laboratory chemical analysis.
- South America > Brazil (0.50)
- North America > United States > Texas (0.29)
- Energy > Oil & Gas > Upstream (1.00)
- Materials > Chemicals > Commodity Chemicals > Petrochemicals (0.74)
- Well Completion > Well Integrity > Subsurface corrosion (tubing, casing, completion equipment, conductor) (1.00)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Corrosion inhibition and management (including H2S and CO2) (1.00)
- Facilities Design, Construction and Operation > Pipelines, Flowlines and Risers > Materials and corrosion (1.00)
- Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (1.00)
INTRODUCTION ABSTRACT Fumes from a pharmaceutical production plant and its support facilities are drawn into one of two regenerative thermal oxidizers (RTOs) where they are destroyed to acceptable regulatory standards. Furan and vinyl ester fiberglass reinforced plastic (FRP) ducts are successfully being used to transport the fumes from their origin to the RTOs. The fumes range from concentrated (above upper explosive limit) to dilute (<15% lower explosive limit) mixtures of various chlorinated and non- chlorinated solvents. Each section of the fume transport system (FTS) is specifically designed based on pressures, solvent type, solvent concentration, temperature, moisture and flow. The ducts range in size from 4 to 120 inches (10.2 cm to 3.05m). This paper will discuss the general design, application and performance of each major portion of the FTS. In addition, it will emphasize the importance of ancillary equipment such as access points, grounding, connectors, and relief systems in the design. During the production of specific pharmaceuticals, a variety of both chlorinated and non-chlorinated solvents must be utilized. Some of the emissions from these solvents are highly flammable at low concentrations and are also listed as hazardous air pollutants (HAPs) by the Environmental Protection Agency (EPA). One such facility voluntarily constructed a system in the early 1990's capable of capturing and destroying the emissions from the manufacturing processes. Two regenerative thermal oxidizers (RTOs) were installed and are being utilized to destroy the process emissions. One of the biggest obstacles was determining how to safely and cost effectively transport the solvent emissions (referred to as fumes) from the point of generation to the RTOs. Any time an ignition source is present with a specific ratio of fuel and oxidant (known as the fire triangle), an ignition and fire will occur. If one leg of the fire triangle is not present, an ignition and/or fire will not take place. The fume transport system (FTS) was designed so that no more than one leg of the fire triangle would be present if at all possible. The first safeguard is to ensure that no ignition source is present in the system. Any system utilized must be capable of dissipating electrical energy generated as well as ensuring temperatures are kept below ignition temperatures for the fumes. The electrical energy is dissipated by grounding the duct, valves, probes, and all associated equipment. Temperatures are addressed in the process design phase process hazards reviews (PHRs) and are monitored throughout the system. I f high temperatures are detected, flame transport is stopped. The second safeguard is to ensure that the ratio of oxidant and fuel are not combustible. This is accomplished by nitrogen inerting or air diluting the atmosphere. This facility uses both of these methods but air dilution is the most widely used. Unfortunately, the high concentration of fumes requires large volumes of air to keep the duct contents safely below explosive levels. Typically, the flammable vapor loading is less than 5% of the lower explosive limit (LEL). This factor required some of the FRP to be large diameter, 120 inches (3.05m) so that it was capable of conveying up to 70,000 SCFM (1982 um3/min) at three to six inches of water column vacuum (746 to 1492.8 Pa). Fiberglass reinforced plastic (FRP) ducts were determined to be the best solution to the fume transport issues mentioned above. Areas of the plant that contained high concentrations of fumes and/or the potential for condensation were constructed of flaran. Areas that contained lower concentrations of fumes and little potential for condensation were constructed of vinyl ester.
- Materials > Chemicals > Commodity Chemicals > Petrochemicals (1.00)
- Health & Medicine (1.00)
INTRODUCTION ABSTRACT The dramatic increase in the power of desk top personal computers coupled with advances in relatively low priced software (as compared to similar software for mainframes) has made it possible for the designer of fiberglass reinforced plastic (FRP) vessels to use advanced techniques which at one time were restricted to aircraft, spacecraft and military projects. A large FRP scrubber vessel 25 ft 7 inch (7.8 m) in diameter, a shell length of 79 ft 5 inch (24.2 m) and a skirt length of 14 ft 9 inch (4.5 m) was designed in accordance with ASME RTP- 1 Subpart 3B with advanced computer software. The vessel was designed using a layer-by-layer Finite Element model. The material properties of the layers and macro layers was calculated using lamination analysis. Layer strengths were determined using in some cases with ASME RTP-1 strain limits and in some cases by laboratory testing. The vessel was field fabricated in Europe for a major US petrochemical company and the project was very successful. Finite Element Analysis is unquestionably one of the greatest advancements in engineering analysis of all time. When first introduced, the cost of computer equipment and FEA software limited its use to high budget projects such as military hardware, spacecraft and aircraft design. As the cost of both computer time and the software fell, FEA began to be used for high volume product design in such areas as automotive and computer peripherals. Desktop computers running FEA software have been on the market for about 15 years and both hardware and software have undergone incredible advancements in capability. This has brought the cost of this very advanced tool to a level where it can be used in the design of one-of-a-kind products such as large FRP tanks and vessels. A particularly interesting case history shall be used to demonstrate the capability and benefits of FEA as a practical design tool. TRADITIONAL DESIGN OF FRP VESSELS Fiberglass reinforced plastic (FRP) is a general term for a wide range of composite materials consisting of numerous reinforcement schemes and dozens of types of resins. Mechanical properties of laminates are controlled to a major extent by the reinforcement scheme and to a lesser extent by the resin properties. For corrosion resistant applications, resin selection is normally based on corrosion resistance and temperature range. In some cases elongation is also a factor in resin selection. Basic reinforcement schemes typically found in corrosion resistant vessels may be grouped in three categories: Random fiber, Bi-axial fiber, and Oriented fiber reinforcement. Laminates reinforced with random chopped mat have isotropic macroscopic properties. Laminates reinforced with bi-axial oriented fibers (such as woven roving) have quasi-isotropic macroscopic properties. Laminates reinforced with uni-directional or helically wound oriented fibers have anisotropic macroscopic properties. Before advanced computer based design tools were available, the macroscopic properties of laminates had to be determined by lab testing. There are a number of design standards for FRP tanks and vessels for corrosion applications which have been developed over the years. One of the first was NBS PS15-69. This was followed by ASTM D3299, ASTM D4097 and BS-4994. All of these standards employ the use of simple design formulas for the various vessel components such as cylindrical shells, ASME F&D dished heads, conical heads, etc. The presence of discontinuity stresses and thermal stresses is far outside the scope of these simple design formulas so large design factors were used to account for these "uncalculable" stresses. Typically a design factor of 10 is used for co
- North America > United States (0.29)
- Europe (0.25)
- Materials > Chemicals > Commodity Chemicals > Petrochemicals (0.56)
- Energy > Oil & Gas (0.36)
- Production and Well Operations > Production Chemistry, Metallurgy and Biology > Corrosion inhibition and management (including H2S and CO2) (0.76)
- Management > Professionalism, Training, and Education > Communities of practice (0.62)
- Data Science & Engineering Analytics > Information Management and Systems > Knowledge management (0.62)
ABSTRACT On May 22, 1998, Bridgeport Harbor Station Unit No. 3 operated for nearly four (4) hours with saltwater intrusion into the boiler water and steam systems via a condenser tube leak. After deliberate and detailed study with world-renown corrosion inspection and mitigation experts and EPRI, a plan of action was developed to mitigate the salt water intrusion from the boiler waterwall and steam system, in order to place these portions of the unit in a "before incident" condition. The boiler waterwall system was thoroughly recirculated and flushed with condensate, and then chemically cleaned prior to service. A complete turbine overall has been undertaken, a portion of which includes thorough blasting, surfactant soaking, rinsing and drying of all stages of steam buckets, diaphragms, and turbine blading. A multi-stage high velocity water flush was successfully completed to mitigate saltwater intrusion into the superheat and reheat steam systems. This paper describes the various processes used to successfully return the unit to normal, full load operation, with particular emphasis on the multi- stage high velocity water flush of the steam cycle. INTRODUCTION United Illuminating's Bridgeport Harbor Station Unit No. 3 is a Combustion Engineering [CE] Tangential Fired Controlled Circulation Boiler. Built in 1967, it produces 2,700,000 lb/hr superheated steam at 2600 psig and 1005 °F, with reheat production of 2,387,000 lb/hr at 1005 °F, both feeding a 375 MW General Electric [GEl tandem compound steam turbine. The unit is on the shores of Bridgeport Harbor, Connecticut, and uses the saltwater from the harbor for once-through cooling in various systems. On Friday, May 22, 1998, Unit No. 3 was operating normally at a full load of 375 MW. A massive condenser tube leak occurred at approx. 11:40 am; in ten (10) minutes the "B" hotwell and the boiler feed pump suction conductivities rose to ten (10) times their normal level. The saltwater intrusion into the boiler water and steam systems went unattended for four (4) hours, until a loss of vacuum and load was noticed and found to be uncorrectable and the unit was shut down. Immediate actions were taken to minimize the extent of the contamination. First the boiler waterwall system was thoroughly recirculated and caustic soda added to raise the boiler water pH from 5.3 to a normal 9.4, with conductivities of 1000 gmho and near 80 ppm chlorides. The unit was then drained, refilled from the boiler bottom with water treated with tri-sodium phosphate [TSP] and drained again. A forward flush through the Economizer and out the boiler blow-downs with TSP treated water followed. The unit was next filled with TSP treated water, and circulated for 11 hours before draining. A fourth fill and rinse with TSP was taken to the top of the steam drum, then normalized and recirculated. A fifth flush was circulated with a standard wet lay-up solution of ammonia and hydrazine, and showed no detectable chlorides (less than 50 ppb). The boiler waterwall system was subsequently chemically cleaned with EDTA prior to being placed into service. By Monday morning, the boiler Waterwalls, Economizer, and Steam Drum had been flushed, the steam turbine was being disassembled, and a project organizational team was defined to investigate the root cause of the problem and develop a comprehensive plan of remediation. After deliberate and detailed study with world-renown corrosion inspection and mitigation experts, a plan of action was developed to mitigate the salt water intrusion from the boiler waterwall and steam circuits and steam turbine, in order to place these portions of the unit in a "before incident" condition. A massive, all encompassin
- North America > United States > Connecticut (0.34)
- North America > United States > Texas (0.28)
- Production and Well Operations (1.00)
- Well Drilling > Drilling Fluids and Materials > Drilling fluid selection and formulation (chemistry, properties) (0.54)
- Health, Safety, Environment & Sustainability > HSSE & Social Responsibility Management > Contingency planning and emergency response (0.54)
- (4 more...)
ABSTRACT Top down models that include corrosion damage into a larger scheme of operation are typically based on some simple subjective assessment schemes that do not permit reusability. The difficulties in recording corrosion data are an inherent character of the complexity of the variables involved. Corrosion failures typically occur over long service periods and their impact is often hidden in normal routine replacement operations. This paper reviews some of these top- down models used in critical industries before introducing a generic framework to bridge across missing information gaps for the creation of robust knowledge based systems. INTRODUCTION The transformation of corrosion testing results into usable real life functions for service applications is a very difficult task often generating unreliable data as illustrated in Figure 1 [1]. In the best cases, laboratory tests can provide a relative scale of merit in support of the selection of materials exposed to specific conditions and environments. Models of materials degradation processes have been developed for a multitude of situations using a great variety of methodologies. For scientists and engineers working at developing materials, models have become an essential benchmarking element for the selection and life prediction associated with the introduction of new materials or processes. In fact models are, in a scientific context, an accepted method to represent current understandings of reality. Traditional models can be divided into two main categories: mathematical or theoretical models and statistical or empirical models [2]. Mathematical models have the common trait that the response and predictor variables are assumed free of specification error and measurement uncertainty [3]. Statistical models, on the other hand, are derived from data that are subject to various types of specification, observation, experimental and/or measurement errors.
- Aerospace & Defense (0.94)
- Energy > Oil & Gas > Midstream (0.47)