The diploma thesis includes proposals suitable for usage of the technologies for clearing the biogas into a quality of substitute natural gas (SNG). The most suitable technology is chosen for the clearing the biogas out of the septic tanks of the laboratory for biologically decomposable waste treatment at Institute of process and environmental engineering. There is a calculation , a proposal and a realisation of the experimental unit for clearing the biogas performed.

Gas transport properties of PIM-1 (the first ladder polymer with intrinsic microporosity) and TC-PIM-1 (thermally cross-linked PIM-1) at 35°C and different pressures were thoroughly studied. The purpose of this study was to evaluate and compare the performance of the TC-PIM-1 membranes with PIM-1 for natural gas separation. The TC-PIM-1 polymer was prepared by post-modification of PIM-1 at 300°C for a period of two days. Sorption isotherms of seven gases, including N2, O2, CH4, CO2, C2H6, C3H8 and n-C4H10, were determined for PIM-1 and TC-PIM-1 using the dual-volume barometric sorption technique at 35°C at different pressures. The sorption isotherms followed the dual-mode sorption model, which is typical for glassy polymers. Moreover, permeability (P) of eight gases, including He, H2, N2, O2, CH4, CO2, C3H8 and n-C4H10, were determined for PIM-1 and TC-PIM-1 at 35°C and 2.0 atm. Furthermore, average diffusion coefficients (D ̅) were calculated from the permeability and solubility data for all tested gases for both polymers. The sorption (S), permeability (P) and average diffusion coefficients (D ̅) for the TC-PIM-1 membrane exhibited lower values than the PIM-1 membrane. However, the TC-PIM-1 membrane showed exceptional gas separation performance. The TC-PIM-1 membrane had a helium (He) permeability of 1218 barrer with He/CH4 and He/N2 ideal selectivities of 27.1 and 23.9 respectively, and carbon dioxide (CO2) permeability of 1088 barrer with CO2/CH4 and CO2/N2 ideal selectivities of 24.2 and 21.3 respectively. Additionally, the TC-PIM-1 membrane showed a hydrogen (H2) permeability of 2452 barrer with an ideal H2/CH4 selectivity of 54.5.

Natural gas is among the most dominant resources to provide energy supplies and Saudi Arabia ranks among the top 5 producers worldwide. However, prior to use of methane, natural gas has to be treated to remove other feed gas components, such as H2O, CO2, H2S, N2 and C2+ hydrocarbons. Most NG fields in KSA contain about 10 mol% carbon dioxide that has to be reduced to less than 2 mol% for pipeline delivery. The conventional unit operations for natural gas separations, that is, molecular sieves, amine absorption, cryogenic distillation, and turbo expansion exhibit some disadvantages in terms of economics, operational flexibility or system footprint. One of the most attractive alternative is membrane technology in either standalone- or hybrid system configuration. Currently, the only two membrane materials used in industrial natural gas applications are cellulose acetate and polyimide, which have moderate permeability and fairly low selectivity when tested under realistic industrial conditions. The goal for future research is to develop unique polymeric membranes, which can at least partially replace conventional gas processing in future natural gas projects. This will support global economics and specifically the economy of Saudi Arabia. Newly developed polymeric materials must meet certain criteria to be used on a commercial scale. These criteria include: (i) high permeability and selectivity, (ii) processability into thin films, (iii) mechanical and thermal stability, and (iv) chemical stability against feed gas components. This project focused on the removal of carbon dioxide from natural gas by developing and characterizing functionalized aromatic polyimide membrane materials that exhibit very high selectivity under aggressive mixed-gas conditions. 6FDA-DAR demonstrated a mixed-gas CO2/CH4 selectivity of 78 at a CO2 partial pressure of 10 bar with no pronounced indication of plasticization. Combining hydroxyl- and carboxyl groups in a miscible polyimide blend led to mixed-gas CO2/CH4 selectivity of 100 with no aging and no plasticization effects. This burgeoning membrane material has very high potential in large-scale natural gas separations with the best overall performance of any type developed to date.

The use of natural gas as a primary energy source has increased over time and is expected to increase even further in the near future. Cyprus and Israel, two countries in the Eastern Mediterranean, have recently made major offshore discoveries of natural gas, sufficient enough to cover their own needs for at least the next few decades and use an even greater amount for export. In this project, the software MESSAGE was used to conduct modelling of the two countries’ energy systems. Projections were made until 2050 of the electricity generation in each country from each major energy source under different scenarios and the possibility of exporting electricity, liquefied natural gas (LNG) or gas-to-liquid products (GTL) was assessed.

In late 1992 coalbed methane became the most significant source of natural gas produced in Virginia. This gas is held within the coal formations adsorbed to the coal matrix. The current well stimulation technology applies a high pressure fluid to the coal formation surrounding the wellbore to induce a series of fractures. The research documented in this thesis investigates several new technologies that could replace or augment the current well stimulation approach of hydraulic fracturing. The application of liquid carbon dioxide, as the stimulation agent was investigated in a series of permeability tests. These measurements were made using a radial flow technique developed specifically for this research project. The results of the tests using liquid carbon dioxide to enhance the permeability of coal samples, to methane gas, indicated a significant increase in permeability of the samples. Comparison to a reference material showed, however, that the increase was of a general nature, not by specific interaction with the coal matrix. Rather, the permeability increase was due to reduced resistance of the borehole skin. Studies of the new, radial flow, permeability measurement approach showed good agreement to a conventional, axial flow, approach for similar sample bedding orientation to the gas flow. The documented experiments also include investigations into the potential for using custom designed nitrocellulose/nitroglycerin/RDX based propellant charges to produce extensive fracturing away from the wellbore. The first series of these experiments concerned the characterization of the burn properties for these propellants and their mixtures. Utilizing an interior ballistics approach, these laboratory small-scale shots were numerically modeled with a program written as a part of this project. Using the small-scale results and the modeled data, a series of large-scale test shots were developed and fired to gain understanding of the scale effects. The small-scale constant volume bomb, and the large-scale vented bomb were both custom designed and fabricated for this project. Comparisons of the laboratory data and modeled predictions show good agreement for both the small and large-scale test series. This work concludes by presenting considerations for utilizing the propellant based well stimulation approach in the water filled wells in southwest Virginia. / Ph. D.

A reform of the constitutional bases of the oil and gas industry in Mexico took place in 2013 (with sweeping changes to secondary legislation through 2014). Private and foreign production of hydrocarbons became legal after almost six decades of national monopoly --and 75 years after the revolutionary regime nationalized the assets of foreign producers. A wholesale market for electricity was also put in place. These legal reforms started to crystallize in 2018, as private producers started to have access to the networks carrying electricity and gas across the nation. This research presents a retrospective examination of 23 years of policy implementation in the natural gas industry of Mexico (1995-2018). The dissertation pays central attention to the patterns of state intervention that have characterized the national economy and that have contributed to shape the outcome of two policy packages pursuing liberalisation (one starting in 1995 and the other in 2013 and 2014). The research is based on a classical political economy approach, drawing on the literature on Varieties of Capitalism and Varieties of State Capitalism. The study centers on the relations between the players in the sector: their constraints and resources, against a backdrop of other economic policies affecting energy. Importantly, this study considers regulation as a mechanism of economic coordination. As a process-tracing case study, this thesis sets out to elucidate the distinctive factors that contributed to produce the current organization of the natural gas sector in Mexico --one where, ironically, liberalisation has been possible thanks to the deployment of a new state-owned enterprise. Three factors stand out as characteristic in the Mexican trajectory towards liberalisation: the strength of the national oil company as an obstacle of upstream liberalisation for almost two decades after 1995; the absence or weakness of constituencies supporting the restructuring of the sector (large industrial consumers, local distributors), and the sudden restructuring of supply and demand patterns, with the state-owned electricity enterprise emerging as a dominant trader. The new centrality of the electricity SOE and an Independent System Operator (also an SOE) underscores the limits of the new, more competitive, structure of the Mexican natural gas industry.

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As climate change continues to intensify, growing interest in equitable clean energy transition has emerged to address the environmental and public health impacts of aging energy infrastructure. Of special concern is aging natural gas infrastructure, which serves as a significant source of the potent greenhouse gas (GHG) methane (CH4) and poses risk to the health and safety of the public. The concentration of aging natural gas distribution pipelines in urban centers has motivated this research, examining dynamic interactions among natural gas distribution pipelines, street tree canopies, and local climate action plans. This dissertation approaches the study of urban natural gas systems using an infrastructure ecology framework – a framework to investigate the dynamic relationships among elements of built, natural, and social infrastructure. The results of three studies reported below aim to improve our knowledge of the environmental impacts of aging natural gas infrastructure in urban centers and examine policy opportunities for a clean energy transition. Using a temporal and spatial dataset of street tree condition and soil CH4 and oxygen concentrations across Brookline, MA we were able to model the impact of CH4 on the success of a street tree using the spatial Durbin model. We find that persistent exposure to CH4 and diminished oxygen in the soil pit is correlated with poor tree condition. Next, utilizing a novel virtual data collection application, we tracked the location of leak-prone natural gas distribution infrastructure along the streets of Chelsea, MA. By producing and combining this unique dataset with the comprehensive street tree inventory completed by the municipality, we examined for the first time the relationship between street tree condition and proximity to leak-prone distribution pipe. Results from this analysis were suggestive and demonstrated a need for more comprehensive spatial data collection using virtual tools that can detect dynamic changes in the infrastructure to explain phenomena we are not yet able to interpret. Findings suggest the importance of considering the location of leak-prone pipelines when planting new street trees and protecting existing mature trees. Finally, we introduce the term and conceptual framework ‘infrastructure biome’ to define and describe the interconnected and dependent built, social, and natural infrastructure systems that extend beyond jurisdictional borders. We propose that energy transition policy, specifically a transition off natural gas, would benefit from a regional collaborative policy to achieve the ambitious climate action goals of cities and states throughout the region. Using publicly available natural gas pipeline data, we examine aging and leak-prone natural gas infrastructure for the first time at a regional scale and recommend a collaborative policy to address the shared obstacle of aging natural gas infrastructure to achieve climate action goals.

Due to the advancement of global warming internationally, increasing emphasis is being placed on the environmental accountability of everyone from countries to processes. This study presents novel research on the environmental impacts and economic trade-offs for a processes co-producing electricity, methanol, dimethyl ether (DME) and Fischer Tropsch (FT) fuels from different feedstock ratios of biomass, natural gas, and nuclear hydrogen generated through a CuCl cycle are analyzed for operation in Canada to produce transportation fuels. This study also considers the use of carbon capture and sequestration (CCS), the location of the plant in either Ontario and Alberta, and the input ratio of the feedstocks. This combination of carbonless heat and a “carbon neutral” biomass feedstock would contribute to the net reduction of greenhouse gas (GHG) emissions. In Part I of this work, the model for this BGNTL process was developed. This work expands on the model and evaluates the economics and environmental impacts this plant would have in both Ontario and Alberta based on their local costs, resource availability, and current electricity grid contributions. The analysis investigates the effectiveness of the emission reduction of the products and processes when compared to their cost. It is shown that an increase in the ratio of biomass to natural gas in feedstock, the use of a solid oxide fuel cell (SOFC), and the production of additional electricity while reducing the emissions of the process, increases the cost of CO2e avoided. The results show that the BGNTL concept can be an economically attractive way of reducing net transportation sector GHG emissions in both Ontario and Alberta in meaningful quantities. Optimal cases for both biofuel and FT fuel production contain a single output fuel production process, produce fuels over electricity where possible, and use a gas turbine (GT) for the electricity production that occurs. / Thesis / Master of Engineering (MEngr) / This paper examines a system producing a combination of transportation fuels including diesel, gasoline, methanol (MeOH), dimethyl ether (DME) and electricity from biomass, natural gas and hydrogen. The design of the system units used in the process was done in a previous study, this work expands on the design looking specifically at locating the plant in Ontario and Alberta for their raw resources, electricity grids, and current production methods of fuel. Variations of the plant are compared to each other and current fuel and electricity production with an aim of reducing the cost and emissions created while producing and using the fuels. It is found that increasing the amount of biomass used significantly reduces the emissions but does not create a competitive process due to how expensive it is. Results show that this type of system can decrease transportation sector emissions with a similar additional cost as other current alternatives.