Development of a Remote External Repair Tool for Damaged or Defective Polyethylene Pipe

Current procedures for repairing polyethylene (PE) gas pipe require excavation, isolation, and removal of the damaged section of pipe followed by fusing a new section of pipe into place. These techniques are costly and very disruptive. An alternative repair method was developed at Timberline Tool with support from Oregon State University (OSU) and funding by the U. S. Department of Energy National Energy Technology Laboratory (DOE/NETL). This project was undertaken to design, develop and test a tool and method for repairing damaged PE pipe remotely and externally in situ without squeezing off the flow of gas, eliminating the need for large-scale excavations. Through an iterative design and development approach, a final engineered prototype was developed that utilizes a unique thermo-chemical and mechanical process to apply a permanent external patch to repair small nicks, gouges and punctures under line pressure. The project identified several technical challenges during the design and development process. The repair tool must be capable of being installed under live conditions and operate in an 18-inch keyhole. This would eliminate the need for extensive excavations thus reducing the cost of the repair. Initially, the tool must be able to control the leak by encapsulating the pipe and apply slight pressure at the site of damage. Finally, the repair method must be permanent at typical operating pressures. The overall results of the project have established a permanent external repair method for use on damaged PE gas pipe in a safe and cost-effective manner. The engineered prototype was subjected to comprehensive testing and evaluation to validate the performance. Using the new repair tool, samples of 4-inch PE pipe with simulated damage were successfully repaired under line pressure to the satisfaction of DOE/NETL and the following natural gas companies: Northwest Natural; Sempra Energy, Southwest Gas Corporation, Questar, and Nicor. However, initial results of accelerated age testing on repaired pipe samples showed that the high density polyethylene (HDPE) pipe patch material developed a small crack at the high stress areas surrounding the patched hole within the first 48 hours of hot water testing, indicating that the patch material has a 25-year lifespan. Based on these results, further research is continuing to develop a stronger repair patch for a satisfactory 50-year patch system. Additional tests were also conducted to evaluate whether any of the critical performance properties of the PE pipe were reduced or compromised by the repair technique. This testing validated a satisfactory 50-year patch system for the pipe

Efficient Fabrication of Nanoporous Si and Si/Ge Enabled by a Heat Scavenger in Magnesiothermic Reactions

Magnesiothermic reduction can directly convert SiO₂ into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to convert diatom (SiO₂) and SiO₂/GeO₂ into nanoporous Si and Si/Ge composite, respectively. Fusion of NaCl during the reaction consumes a large amount of heat that otherwise collapses the nano-porosity of products and agglomerates silicon domains into large crystals. Our methodology is potentially competitive for a practical production of nanoporous Si-based materials.Keywords: Energy storage, Nanoparticles, Porous silicon, Nanowires, Chemical reduction, Dioxide, Electrodes, Anode materials, Lithium ion batteries, Crystallin

Gas-liquid segmented flow microwave-assisted synthesis of MOF-74(Ni) under moderate pressures

The metal organic framework, MOF-74(Ni), was synthesized in a continuous flow microwave-assisted reactor obtaining a high space-time yield (~90 g h⁻¹ L⁻¹) and 96.5% conversion of reagents. Separation of the nucleation and growth steps was performed by using uniform and rapid microwave heating to induce nucleation, which allowed a substantial increase in conversion for shorter reaction times under mild pressure. High yields were achieved in minutes, as opposed to days for typical batch syntheses, with excellent control over the material's properties due to more uniform nucleation, and the separation of the nucleation and growth steps. Optimization of the microwave reactor parameters led to improvements in MOF-74(Ni) crystallinity, reagent conversion, and production rates. Differences in MOF-74(Ni) crystallinity were observed as smaller grains were formed when higher microwave zone temperatures were used. Crystallinity differences led to different final adsorption properties and surface areas. Herein we show that a continuous high space-time yield synthesis of MOF-74(Ni) allows control over nucleation using microwave heating

High-Rate Synthesis of Cu-BTC Metal-Organic Frameworks

The reaction conditions for the synthesis of Cu-BTC (BTC = benzene-1,3,5-tricarboxylic acid) were elucidated using a continuous-flow microreactor-assisted solvothermal system to achieve crystal size and phase control. A high-rate synthesis of Cu-BTC metal-organic frameworks with BET surface area of more than 1600 m²/g (Langmuir surface area of more than 2000 m²/g) and with a 97% production yield could be achieved with a total reaction time of 5 minutes

ChangChih-Hung(Alex)ChemicalBiologicalEnvironmentalEngineeringHighRateSynthesis.pdf

The reaction conditions for the synthesis of Cu-BTC (BTC = benzene-1,3,5-tricarboxylic acid) were elucidated using a continuous-flow microreactor-assisted solvothermal system to achieve crystal size and phase control. A high-rate synthesis of Cu-BTC metal-organic frameworks with BET surface area of more than 1600 m²/g (Langmuir surface area of more than 2000 m²/g) and with a 97% production yield could be achieved with a total reaction time of 5 minutes

ChangChih-Hung(Alex)CBEEHighRateSynthesis(SupportingInformation).pdf

The reaction conditions for the synthesis of Cu-BTC (BTC = benzene-1,3,5-tricarboxylic acid) were elucidated using a continuous-flow microreactor-assisted solvothermal system to achieve crystal size and phase control. A high-rate synthesis of Cu-BTC metal-organic frameworks with BET surface area of more than 1600 m²/g (Langmuir surface area of more than 2000 m²/g) and with a 97% production yield could be achieved with a total reaction time of 5 minutes

Annual program review chemical recovery and corrosion : March 25-26, 1998

"March 25-26, 1998."Project F016-01. Control of evaporator fouling. Current trends in evaporator fouling / Wolfgang Schmidl, Wm. James Frederick -- Project F016-02. Recovery boiler modeling -- Project F016-03. Recovery boiler capacity improvements. Experimental study of the mechanisms of fine particle deposition in kraft recovery boilers / S. A. Sinquefield, L. L. Baxter, W. J. Frederick -- Project F017-04. Control of non-process elements in kraft pulp mills and bleach plants. Distribution of non-process elements in pulp mill and bleach process streams. 1. Calculating precipitation of inorganic species / W. J. Frederick, G. W. Schmidl, and C. P. Woitkovich, S. A. Sinquefield ; Solubility of aluminosilicates in kraft green and white liquors / P. N. Wannemacher, Wm. James Frederick, K. A. Hendrickson, K. L. Holman -- Project F017-06. Closed mill salt recovery / P. Pfromm Highlights of externally funded and PhD projects: Project 4182. Elimination of the calcium cycle: direct electrolytic causticizing of kraft smelt ; Project 4157-02. VOC control in kraft mills. Task B, Development of a membrane separation technology ; Project 4160. Recycling of bleach plant filtrates using electrodialysis ; Removal of inorganics from close-cycle papermachine white water ; Behavior of polymeric toner in recycling ; Removal of potassium from green liquor by ion exchange -- Project F017-07. Fundamentals of dregs removal / [Empie ... et al.] -- Project F017-08. VOC in Kraft mills. Volatile organic compounds (VOCs) in kraft mill streams. Part II, Protocol development to measure the contents and Henry's constants of VOC's in kraft mill streams / J.Y. Zhu, X.S. Chai, and B. Dhasmana ; Volatile organic compounds (VOCs) in kraft mill steams. Part III, Vapor-liquid phase equilibrium partitioning of methanol in black liquors / J.Y. Zhu and X.S. Chai -- Project F028. Gasification of black liquor / Kristiina Iisa -- Slides