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New energy plants coming online must be both economical and efficiently balanced to satisfy demanding requirements in the future. A balance of plant analysis was performed to determine the techno-economic feasibility of a 100 barrel oil equivalent (boe) per day, compact Gas to Liquid (GTL) methanol plant. Methanol itself is emerging as a possible alternative to gasoline; but it is also the precursor to dimethyl ether (DME), which has recently received a lot of attention as a low emitter of particulate matter and nitrous oxides, which can replace diesel in trucking applications and liquefied petroleum gas (LPG) in domestic applications. Production of synthesis gas (syngas) from methane gas was modeled via partial oxidation of fuel-rich mixtures in engine cylinders using GT-ISE. Two ignition modes were studied: spark ignition (SI) and homogeneous charge compression ignition (HCCI). The use of the engine as a compressor was also studied in order to reduce net compression requirements and therefore capital and operating costs. The low brake mean effective pressure (BMEP) allowed in HCCI operation substantially limits both the throughput and capability to produce high-pressure syngas. The use of mechanical power generated by the engine reformer to power other components such as compressors and the air separation unit (ASU) have been studied. The waste heat produced from the engine and methanol synthesis reactors was also considered in the analysis. Integration of all components in the system was performed in Aspen Plus. To inform plant design, a survey was performed of vendors with small-scale methanol synthesis technologies that could integrate an engine reformer. Aspen Process Economic Analyzer (APEA) was also used to generate estimates of plant component costs. A study of the profitability and payback period of the technology was performed to determine the cost to produce methanol based on the balance of plant analysis. The results of this analysis were used to gauge the technology’s feasibility and therefore provided constructive feedback to guide future plant design.

Methane (CH 4 ) reforming was carried out in an internal combustion engine (an "engine reformer"). We successfully produced syngas from the partial oxidation of natural gas in the cylinder of a diesel engine that was reconfigured to perform spark ignition. Performing the reaction in an engine cylinder allows some of the exothermicity to be captured as useful work. Intake conditions of 110 kPa and up to 480 8C allowed low cycle-to-cycle variability (COV nimep < 20 %) at methane-air equivalence ratios (f M ) of 2.0, producing syngas with an H 2 -to-CO ratio of 1.4. Spark ignition timing was varied between 45-308 before top-dead-center (BTDC) piston position, showing significant improvement with delayed timing. Hydrogen (H 2 ) and ethane (C 2 H 6 ) were added to simulate recycle from a downstream synthesis reactor and realistic natural gas compositions, respectively. Adding these gases yielded a stable combustion up to hydrocarbon-air equivalence ratios (f HC ) of 2.8 with COV nimep < 5 %. Ethane concentrations (with respect to methane) of up to 0.2 L/L (20 vol%) (with and without H 2 ) produced robust and stable combustions, demonstrating that the engine can be operated across a range of natural gas compositions. Engine exhaust soot concentrations demonstrated elevated values at f HC > 2.4, but < 1 mg/L below these equivalence ratios. These results demonstrate that the engine reformer could be a key component of a compact gas-to-liquids synthesis plant by highlighting the operating conditions under which high gas conversion, high H 2-to-CO ratios close to 2.0, and low soot production are possible.

In the present study, a catalyst produced by flame spray pyrolysis (FSP) was evaluated for its ability to produce hydrogen-rich gas mixtures. Catalyst particles fabricated by a novel flame spray pyrolysis method resulting in a highly active catalyst with high surface-to-volume ratio were compared to a commercially produced catalyst (BASF F3-01). Both catalysts consisted of CuO/ZnO/Al2O3 of identical composition (CuO 40wt%, ZnO 40wt%, Al2O3 20wt%). Reaction temperatures between 220 and 295 °C, methanol-water inlet flow rates between 2 and 50 μl/min, and reactor masses between 25 and 100 mg were tested for their effect on methanol conversion and the production of undesired carbon monoxide. 100% methanol conversion can be easily achieved within the operational conditions mentioned for this flame-made catalyst — at reactor temperatures of 255 °C (achievable with non-concentrating solar collectors) more than 80% methanol conversion can be reached for methanol-water inlet flow rates as high as 10 μl/min. The FSP catalyst demonstrates similar catalytic abilities as the BASF, produces a consistent gas composition and produces lower overall CO production. Furthermore, the FSP catalyst demonstrates a better suitability to fuel cell use through its higher resistance to degradation and smaller production of carbon monoxide over long-term use. In the present study, the merits of using flame spray pyrolysis to produce CuO/ZnO/Al2O3 methanol steam reforming catalysts are examined, and directly compared to catalysts that are commercially produced in bulk pellet form, and then ground and sieved. The comparison is performed from several different perspectives: catalytic activity and CO production at various temperatures and fuel inlet flow rates; surface and structure characteristics are determined via scanning electron and transmission electron microscopy; surface area characteristics are determined via BET tests.

When developing a first-generation product, an iterative approach often yields the shortest time-to-market. In