Environmental and Safety Assessments of Industrial Production of Levulinic Acid via Acid-Catalyzed Dehydration

Abstract

These days, there is a need to develop novel and emerging processing pathways that permit production of value-added substances and fuels considering sustainability aspects. In this sense, levulinic acid (LA) is one of the most promising biorefinery products. This paper presents environmental and safety assessments of LA production via acid-catalyzed dehydration (ACD) of biomass. The process was modeled by using Aspen Plus process simulation software based on a capacity of 132 000 tons per annum of banana rachis (main raw material). Likewise, environmental and safety assessments were developed. Parameters such as heats of reaction, explosivity, toxicity of substances, and operational conditions along with extended mass and energy balances were used to perform safety and environmental analyses. In this regard, the modeled topology showed an inherent safety index (ISI) score of 24 with an equal contribution of 12 points for both chemical inherent safety index (CIS) and process inherent safety index (PIS). ACD showed a good safety performance, with moderate concerns related to the handling of formic acid. Moreover, the waste reduction algorithm (WAR) was used to assess environmental performance and estimate potential environmental impacts (PEIs) of the simulated topology. It was performed considering four case studies to determine the influence of mass streams (case 1), product streams (case 2), energy streams (case 3), and simultaneous products and energy contribution (case 4). This analysis showed that for this process, the total inletting flow of impacts that enter was less than the amount of these that leave the system according to a generation rate of the PEI for case 1 (−1.89 × 102 PEI/h) and case 3 (−1.83 × 102 PEI/h). From the environmental viewpoint, the major concern is associated with the photochemical oxidation potential category because of the handling of volatile organic compounds through the process.

Process Analysis of Hydrogen Production via Biomass Gasification under Computer-Aided Safety and Environmental Assessments

“…We selected natural gas as the base energy source, considering the recommendation of previous studies for analogous topologies. 38 Figure 2 displays the obtained PEI rates based on the proposed scenarios on time and mass of product basis. In Figure 2 , I gen refers to the generation rate, while I out is the output rate.…”

“…Recently, the evaluation of the process safety of emerging and green-based technologies has attracted much interest regarding the sustainability of the plants. Meramo-Hurtado et al 38 used inherent safety (and environmental) analysis along with computer-aided process engineering to evaluate and diagnose an industrial synthesis of levulinic acid via acid-catalyzed dehydration, as a strategy for crop waste valorization. A crude palm oil process was examined by Moreno-Sader et al, 39 implementing hazard/risk identification and environmental evaluation methods.…”

Inherent safety Analysis and Sustainability Evaluation of Chitosan Production from Shrimp Exoskeleton in Colombia

“…Furthermore, was found that in the process is handled large amounts of mass that represent a stressed factor for the safety of the plant; therefore, the most critical and risky operational variable is the inventory. Comparing the results with those obtained for the inherent safety analysis of a levulinic acid production process via acid-catalyzed (I = 24) [37] and a bioethanol production process (I = 23) [38], it is found that the process under study has a lower safety performance. Although substances of equal risk potential such as ethanol are involved and exothermic reactions are performed, these two processes handle lower inventories.…”

“…Also, the operational pressure was kept at atmospheric conditions (101.32 kPa), which represents no risk to the process. The inventory subindex measures the mass contained in any process equipment ( tanks, reactors, mixers, and others) for a hydraulic retention time of 1 h [37]. A total inventory of 1,500 tones was calculated for the inside battery limits (ISBL); the outside battery limits (OSBL) were not considered in the inventory calculation due to the main processing units belongs to ISBL.…”

“…In this process, the reactors and dryers are the equipment with the highest potential risks, therefore, a value of 2 is assigned for this subindex. Finally, the safe structure subindex is determined by considering historical data and reports from heuristics and engineering experience of well-known processes [37]. However, there is no historical information related to the safety of a chitosan production process from shrimp exoskeleton, hence a neutral position is assumed.…”