Techno-Economic Analysis Of Bioconversion Of Glycerol Into 1, 3-Propanediol

1,3-Propanediol(1,3-PD) can be formulated into a variety of industrial products,including aliphatic polyesters,polyurethane,solvent,antifreeze and protecting agents,etc.Besides, 1,3-PD is an important building block in synthesizing Polytrimethylene Terephthalate (PTT)—a new kind of thermoplastic.Using glycerol to produce 1,3-PD is a promising method in the production of bio-based bulk chemicals,and a complete producing process has already been put into pilot production.In order to apply this process into industrial production, a systematically optimization of the whole process should be made based on the techno-economic analysis.Therefore,in this paper,the continuous glycerol bioconversion process and its separation process including alcohol precipitation technique were investigated. Results of material and energy consumptions were calculated by simulating the fermentation and separation process;further,by applying economic methods,costs and profits under different operational conditions were evaluated,thus the process could be optimized from a view of techno-economic way.Firstly,given the different dilution rates and initial glycerol's concentrations,the optimal 1,3-PD's concentrations,productivities,yields with other products' concentrations were calculated by simulating the continuous fermentation of glycerol into 1,3-PD.The results showed that:the increasing dilution rates would decrease 1,3-PD's concentrations as well as yields,but increase the productivities simultaneously,and the highest productivity was reached at the dilution rate of 0.28 h^-1.Next,by choosing eight groups of dynamic simulation results with different operational conditions,the compositions of broth flows were calculated and further,downstream process of separation was simulated with PROⅡ(a process simulating software).Then,the results were applied into techno-economic analysis.It can be concluded that:the increasing dilution rates would increase the broth flow and the total energy consumptions;simply increasing the productivity or yield would not significantly increase the profit;optimal operational conditions could be predicted,based on the techno-economic results. Finally,the sensitivity analysis showed that the cost of glycerol was the key factor influencing the profit.Further,the cost of glycerol could be saved,and the profit-making capability be improved by applying integrated production of biodiesel and 1,3-propanediol. The analysis also indicated:increasing the production scale would decrease the equipment cost,but it might also lead to marginal profit decreasing.