Optimal Integrated Plant for Biodegradable Polymer Production

An integrated facility for the production of biodegradable polymers from biomass residues has been developed. Lignocellulosic residues (sawdust), CO₂, and organic waste such as manure or sludge are the raw materials. Manure and sludge are digested to provide the nutrients needed to grow algae. Algae are used in full to oil and starch production. The oil is transesterified with methanol generated via biogas dry reforming to obtain biodiesel and glycerol. The starch is used together with glycerol and the pretreated sawdust for the production of the biodegradable polymer. A mathematical optimization approach is used to identify the best use of each resource and the optimal operation of the integrated facility for each case. 4732 kt/yr of manure or 4653 kt/yr of sludge was processed to produce 354 kt/yr of biopolymer and 84 Mgal/yr of fatty acid methyl ester, capturing 2.47 kg of CO₂ per kg of biopolymer with production costs of 0.89 and 0.95 $/kg, respectively, and an investment capital of 717 and 712 M$, respectively.