2 resultados para Railway interlockings
em Digital Commons - Michigan Tech
Resumo:
To mitigate greenhouse gas (GHG) emissions and reduce U.S. dependence on imported oil, the United States (U.S.) is pursuing several options to create biofuels from renewable woody biomass (hereafter referred to as “biomass”). Because of the distributed nature of biomass feedstock, the cost and complexity of biomass recovery operations has significant challenges that hinder increased biomass utilization for energy production. To facilitate the exploration of a wide variety of conditions that promise profitable biomass utilization and tapping unused forest residues, it is proposed to develop biofuel supply chain models based on optimization and simulation approaches. The biofuel supply chain is structured around four components: biofuel facility locations and sizes, biomass harvesting/forwarding, transportation, and storage. A Geographic Information System (GIS) based approach is proposed as a first step for selecting potential facility locations for biofuel production from forest biomass based on a set of evaluation criteria, such as accessibility to biomass, railway/road transportation network, water body and workforce. The development of optimization and simulation models is also proposed. The results of the models will be used to determine (1) the number, location, and size of the biofuel facilities, and (2) the amounts of biomass to be transported between the harvesting areas and the biofuel facilities over a 20-year timeframe. The multi-criteria objective is to minimize the weighted sum of the delivered feedstock cost, energy consumption, and GHG emissions simultaneously. Finally, a series of sensitivity analyses will be conducted to identify the sensitivity of the decisions, such as the optimal site selected for the biofuel facility, to changes in influential parameters, such as biomass availability and transportation fuel price. Intellectual Merit The proposed research will facilitate the exploration of a wide variety of conditions that promise profitable biomass utilization in the renewable biofuel industry. The GIS-based facility location analysis considers a series of factors which have not been considered simultaneously in previous research. Location analysis is critical to the financial success of producing biofuel. The modeling of woody biomass supply chains using both optimization and simulation, combing with the GIS-based approach as a precursor, have not been done to date. The optimization and simulation models can help to ensure the economic and environmental viability and sustainability of the entire biofuel supply chain at both the strategic design level and the operational planning level. Broader Impacts The proposed models for biorefineries can be applied to other types of manufacturing or processing operations using biomass. This is because the biomass feedstock supply chain is similar, if not the same, for biorefineries, biomass fired or co-fired power plants, or torrefaction/pelletization operations. Additionally, the research results of this research will continue to be disseminated internationally through publications in journals, such as Biomass and Bioenergy, and Renewable Energy, and presentations at conferences, such as the 2011 Industrial Engineering Research Conference. For example, part of the research work related to biofuel facility identification has been published: Zhang, Johnson and Sutherland [2011] (see Appendix A). There will also be opportunities for the Michigan Tech campus community to learn about the research through the Sustainable Future Institute.
Resumo:
The Michigan Department of Transportation is evaluating upgrading their portion of the Wolverine Line between Chicago and Detroit to accommodate high speed rail. This will entail upgrading the track to allow trains to run at speeds in excess of 110 miles per hour (mph). An important component of this upgrade will be to assess the requirement for ballast material for high speed rail. In the event that the existing ballast materials do not meet specifications for higher speed train, additional ballast will be required. The purpose of this study, therefore, is to investigate the current MDOT railroad ballast quality specifications and compare them to both the national and international specifications for use on high speed rail lines. The study found that while MDOT has quality specifications for railroad ballast it does not have any for high speed rail. In addition, the American Railway Engineering and Maintenance-of-Way Association (AREMA), while also having specifications for railroad ballast, does not have specific specifications for high speed rail lines. The AREMA aggregate specifications for ballast include the following tests: (1) LA Abrasion, (2) Percent Moisture Absorption, (3) Flat and Elongated Particles, (4) Sulfate Soundness test. Internationally, some countries do require a highly standard for high speed rail such as the Los Angeles (LA) Abrasion test, which is uses a higher standard performance and the Micro Duval test, which is used to determine the maximum speed that a high speed can operate at. Since there are no existing MDOT ballast specification for high speed rail, it is assumed that aggregate ballast specifications for the Wolverine Line will use the higher international specifications. The Wolverine line, however, is located in southern Michigan is a region of sedimentary rocks which generally do not meet the existing MDOT ballast specifications. The investigation found that there were only 12 quarries in the Michigan that meet the MDOT specification. Of these 12 quarries, six were igneous or metamorphic rock quarries, while six were carbonate quarries. Of the six carbonate quarries four were locate in the Lower Peninsula and two in the Upper Peninsula. Two of the carbonate quarries were located in near proximity to the Wolverine Line, while the remaining quarries were at a significant haulage distance. In either case, the cost of haulage becomes an important consideration. In this regard, four of the quarries were located with lake terminals allowing water transportation to down state ports. The Upper Peninsula also has a significant amount of metal based mining in both igneous and metamorphic rock that generate significant amount of waste rock that could be used as a ballast material. The main drawback, however, is the distance to the Wolverine rail line. One potential source is the Cliffs Natural Resources that operates two large surface mines in the Marquette area with rail and water transportation to both Lake Superior and Lake Michigan. Both mines mine rock with a very high compressive strength far in excess of most ballast materials used in the United States and would make an excellent ballast materials. Discussions with Cliffs, however, indicated that due to environmental concerns that they would most likely not be interested in producing a ballast material. In the United States carbonate aggregates, while used for ballast, many times don't meet the ballast specifications in addition to the problem of particle degradation that can lead to fouling and cementation issues. Thus, many carbonate aggregate quarries in close proximity to railroads are not used. Since Michigan has a significant amount of carbonate quarries, the research also investigated using the dynamic properties of aggregate as a possible additional test for aggregate ballast quality. The dynamic strength of a material can be assessed using a split Hopkinson Pressure Bar (SHPB). The SHPB has been traditionally used to assess the dynamic properties of metal but over the past 20 years it is now being used to assess the dynamic properties of brittle materials such as ceramics and rock. In addition, the wear properties of metals have been related to their dynamic properties. Wear or breakdown of railroad ballast materials is one of the main problems with ballast material due to the dynamic loading generated by trains and which will be significantly higher for high speed rails. Previous research has indicated that the Port Inland quarry along Lake Michigan in the Southern Upper Peninsula has significant dynamic properties that might make it potentially useable as an aggregate for high speed rail. The dynamic strength testing conducted in this research indicate that the Port Inland limestone in fact has a dynamic strength close to igneous rocks and much higher than other carbonate rocks in the Great Lakes region. It is recommended that further research be conducted to investigate the Port Inland limestone as a high speed ballast material.