A systematic global optimization‐based process synthesis framework is presented to determine the most profitable processes to produce aromatics from natural gas. Several novel, commercial, and/or competing technologies are modeled within the framework, including methanol‐to‐aromatics, toluene alkylation with methanol, selective toluene disproportionation, and toluene disproportionation and transalkylation with heavy aromatics, among others. We propose a stand‐alone chemicals facility: the main products are aromatics with allowable by‐products of gasoline, liquefied petroleum gas, and electricity. Several case studies are discussed that produce varying ratios of para‐, ortho‐, and meta‐xylene across multiple refinery capacities. The results indicate that utilizing natural gas for the production of aromatics is profitable with net present values as high as $3800 MM dollars and payback periods as low as 6 years. The required investment for these refineries represents as much as a 65% decrease compared to published estimates of similar coal‐based capacity plants. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1531–1556, 2016

This paper introduces a process synthesis and a global optimization framework toward the coproduction of liquid fuels and olefins from biomass and natural gas. A superstructure of alternatives is developed at each stage of the process with different gasification options, natural gas conversion routes, hydrocarbon production, and upgrading methods. Simultaneous heat, power, and water integration is introduced for the optimal usage of the utilities in the proposed plants. The global optimization framework with a branch-and-bound approach is utilized to determine the optimal process out of numerous alternatives that would give the maximum plant profit. The optimal topologies obtained suggest that the best possible process depends on the liquid fuels and olefins to be produced. Parametric analysis on different chemicals production levels suggests that both the profit and net present value (NPV) increases substantially at higher chemicals production levels. Economies of scale are present as the case studies at higher capacities result in higher profits and higher net present values. The results suggest that the proposed refineries with coproduction of liquid fuels and olefins are economically viable because of their high and positive NPVs. Furthermore, higher olefins production levels can make the plants more favorable economically.

The pursuit toward an environmentally sustainable energy landscape requires the development of economically competitive renewable processes. Efficient utilization of renewable resources is an important first step toward meeting this goal. To this extent, we introduce a systematic deterministic global optimization-based process synthesis framework that determines the most profitable processes to produce benzene, toluene, and/or xylenes from biomass via methanol. Our framework incorporates several novel, competing, and/or commercial technologies. We quantify the effect that biomass type has on the overall profit of a refinery by investigating forest residues, agricultural residues, and perennial crops as potential feedstocks. A thorough economic analysis, together with material, energy, carbon, and greenhouse gas balances, are provided for every proposed process design. The capability of our proposed approach is illustrated through several case studies that produce varying ratios of p-, o-, and m-xylene across several refinery scales. The most profitable aromatics refineries consistently produce p-xylene, while o-xylene refineries consistently have the lowest required investment costs. The net present values for the biomass to aromatics, BTA, refineries producing 2000 t per day of product are as high as $1200 MM dollars with payback periods less than 10 years.

The thermochemical conversion of coal and biomass to liquid transportation fuels from a synthesis gas intermediate is investigated using an optimization-based process synthesis framework. Two distinct types of coal (LV bituminous and coal commonly found in the province of Anhui, China) and two types of biomass (hardwood and duckweed) are considered as feedstocks. The superstructure incorporates alternative conversion pathways of synthesis gas which include methanol formation and conversion into Fischer–Tropsch hydrocarbons. Methanol may be converted to gasoline or olefins, and the olefins may be subsequently converted to gasoline and distillate. A rigorous deterministic global optimization branch-and-bound framework is utilized to determine the optimal process topology that produces liquid fuels at the lowest possible cost. Economies of scale are evident as the refinery capacity increases and it is observed that the fuel ratios of the final liquid products have a significant impact on the optimal topology of the plant. The results suggest that liquid fuels production from coal and biomass can be competitive with petroleum-based processes.

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Reprinted fromComputers and Chemical Engineering, 81, M. M. F. Hasan et al., A multi-scale framework for CO 2 capture, utilization, and sequestration: CCUS and CCU):2-21, Analysis is determined from the Web of Knowledge database over all research domains, including science technology, social science, and arts humanities.

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The coproduction of liquid transportation fuels and C6C8 aromatics from the thermochemical conversion of biomass and natural gas (BGTL+C6_C8) is investigated in this article. An optimization‐based process synthesis framework incorporating multiple synthesis gas conversion technologies, such as Fischer–Tropsch synthesis or methanol conversion, is described. Production of aromatics can proceed through several technologies, such as naphtha reforming and aromatization of hydrocarbons via a metal‐promoted H‐ZSM‐5 catalyst. This is the first article in the literature to incorporate an aromatics complex for the coproduction of liquid fuels and C6C8 petrochemicals within a rigorous process synthesis and deterministic global optimization framework. The optimal process topologies across several case studies are discussed and the results indicate that the coproduction of aromatics with liquid fuels can significantly increase the profitability of these refineries. © 2015 American Institute of Chemical Engineers AIChE J, 2015 2014 American Institute of Chemical Engineers AIChE J, 61: 831–856, 2015