Hybrid Chemical Looping Model for Sustainable Polygeneration of DME, Methanol, and Ammonia from Biomass with Enviro-Economic Insights

Dimethyl ether (DME), methanol, and ammonia are versatile chemicals that serve as clean energy carriers for sustainable fuels and carbon-neutral energy systems. However, their production routes face challenges owing to a high energy demand, carbon emissions, and limited availability of feedstocks. To overcome these challenges, we developed a hybrid chemical looping (HCL) model by integrating the chemical looping-based ammonia generation (CLAG) process with the three-reactor chemical looping (TRCL) process, representing a win–win approach for polygenerating DME, methanol, and ammonia from inexpensive starting materials. The Aspen-Plus simulated model with 5 metric tons per hour (MTPH) waste biomass processing capacity, comprising biomass pretreatment and devolatilization, CLAG, TRCL, and DME synthesis units, was streamlined to produce ammonia, DME, and methanol with a purity of over 99.9%. To enhance the process energy efficiency, a waste heat recovery module (HCL-WHR) was incorporated and compared to the baseline scenario (HCL-WWHR). Direct-process-related CO2 emissions were captured and converted into liquid CO2, resulting in significant emission savings. Life cycle analysis estimated the global warming potential as −1088.20 kg of CO2 equiv and −2983.36 kg of CO2 equiv in HCL-WWHR and HCL-WHR, respectively, based on a functional unit of 5 MTPH biomass processing capacity. The techno-economic analysis revealed promising economic returns, generating a net present value of $119.79 million by HCL-WHR, based on a 20 year economic plant life. These findings establish the HCL system as a viable and scalable route for the carbon-negative conversion of waste biomass to value-added products.