(314c) Recovery of High-Value Chemicals from Organic Waste: Economic Potential and Logistical Issues
In our supply chain framework, we consider four different sources of organic waste (urban centers, wastewater treatment plants, large dairy farms, and landfills), three different types of waste products (cow manure, sludge residues from wastewater treatment, and food waste) and five different types of waste processing technologies. We assume that 2-4% of the chemical oxygen demand (COD) in the waste streams can be converted as C6 or C8 [5,6]. The constraints in the model involve product balances and conversion constraints, capacity constraints, and logical constraints associated to technology sizing and placement. The objective function is to maximize total profit which includes capital and transportation costs and revenue from the recovered product. We conduct the following studies: a) trade-off analysis of profit against total amount of treated waste in the state, b) effect of uncertainty on yield factors and on prices of waste, C6, and C8, c) effect of waste mixing, and d) comparison of profitability from C6/C8 against the popular biogas (C4) recovery alternative.
Preliminary results indicate that, under current market conditions, it is profitable to recover C6 and C8 from organic waste and that much higher mobility can be achieved compared to C4. The results can be refined by conducting experimental studies that resolve uncertainties in key yield factors and technology costs.
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