Batch Versus Continuous Acetaminophen Production
Globally, acetaminophen is one of the most highly consumed over-the-counter drugs with an estimated market size nearing $10 billion at the close of 2021. Price increases of over-the-counter drugs are driving the market towards generics which places significant pressure on the manufacturing segment to meet the new consumer demand. The largest manufacturers currently operate with an industry standard batch process to synthesize acetaminophen powder at a yield of 30,000MT/year. The chemical engineering community proposes that a continuous process can offer significant benefits including reduced capital and operating costs, improved reaction control, and increased energy efficiency. This project demonstrates that at a production capacity of 30,000MT/year, under identical thermodynamic conditions, a continuous process is over 5 times more profitable than the corresponding batch process. At a price of $4/kg, the continuous process will yield a 15-year Net Present Value (NPV) of $38,000,000 with an Internal Rate of Return (IRR) of 33% compared to $7,300,000 and 18% for the batch process. The continuous process provides increasingly better financial returns as sale price increases relative to the batch process. Multiple factors contribute to the continuous process being more economical. The most significant factor is the lower equipment cost of $40,0200,000 USD for the continuous process compared to $67,300,000 USD for the batch process. Additionally, the continuous process sees lower operating costs in terms of both decreased energy consumption and lower operator costs. These conclusions provide justification for the continued development of a continuous process as the impact on society, pharmacy and the environment could be profound.