A novel design of a coal gasifier using the chemical looping concept is introduced in the present study for high purity, H2-rich syngas generation using coal and methane as cofeeds. In this work, an iron–titanium composite metal oxide (ITCMO), capable of cracking the heavy hydrocarbons produced in coal pyrolysis as well as regulating the product syngas purity, is used as the oxygen carrier. The cocurrent moving bed avoids back-mixing of solid and gas reactants, allowing both phases to interact, reaching thermodynamic equilibrium conditions at the reactor gas outlet. This paper focuses on demonstrating the cocurrent moving bed reducer with the ITCMO oxygen carrier. A sensitivity analysis is performed to determine the optimal operating conditions for converting Powder River Basin coal using ASPEN Plus modeling. The tar-cracking capability is ascertained by the gas chromatography–mass spectrometry analysis. The bench scale moving bed reducer substantiated its capability of achieving near-full conversion of the carbon species. The cofeeding of methane can yield a high purity syngas with H2/CO ratio of 2 or higher, which is suitable for downstream chemical synthesis. The gas and solid compositions obtained at reducer outlets match the predictions from the ASPEN Plus model. The results indicate that the extent of char gasification at the top moving bed is a critical factor for achieving a high coal conversion. The results further indicate that the sulfur in the coal is mostly converted into the gas phase emitted with the syngas product in the reducer, while the remainder is retained in the ash.

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In pipelines, solid compounds including gas hydrates and asphaltenes may form/precipitate and accumulate on the pipe surface, leading to a gradual stenosis of the flowline. As a result, production may become increasingly difficult or possibly interrupted if mitigation efforts are not enacted. Typically, injected chemicals will either inhibit nucleation or dissolve already-formed deposits to restore original flow conditions back to the system; however, this can be a costly option. More recently, management strategies have been proposed where solids are handled in a controlled fashion rather than completely avoided. One such proposed management strategy as suggested for wall deposit formation is the use of coatings. Here, coatings can provide a low surface energy layer on the pipe wall, which restricts liquid and solid accumulation, allowing for a stable slurry flow through a system. This study utilized two material formulations within several experimental setups to probe their interactions with water, gas hydrate, asphaltene, and crude oil. The results serve as part of an ongoing investigation into a surface treatment formulation that can be tested on larger-scale, fully flowing systems, which could be ultimately implemented into real-world production scenarios. The first surface treatment is a water-based polymeric surface that displays repellency to both oil and water phases (omniphobic). Testing of this material consisted of water contact angle measurements and static asphaltene/crude oil deposition quantification at atmospheric conditions, as well as visual confirmation of hydrate deposition prevention at high pressures. Additionally, an experimental superomniphobic surface treatment, which displays elevated resiliency to both water and hydrocarbons, was also examined within the asphaltene/crude oil test as a comparison to the omniphobic surface treatment. Static contact angle results showed that the omniphobic surface treatment had reduced surface interaction with water droplets in air, increasing the low contact angles of corroded surfaces (0-31°) to slightly hydrophobic conditions of 91.5°. Additionally, rocking cells tests indicated that these omniphobic surface treatments may prevent gas hydrate deposition under high-pressure, semi-flowing conditions. Multiple tests found that formed hydrate agglomerants did not deposit for at least 48 and 72 hours. Finally, static deposition tests conducted in crude oil with forced asphaltene precipitation suggested that the omniphobic surface treatment displayed a resistance to both asphaltenes and crude oil when compared to untreated and superomniphobic surfaces.