Abstract Over the past few years, there has been increasing research interest in retrofitting existing combined heat and power (CHP) plants with new technologies to co-produce other products. The focus has been on the design of fixed-sized processes for integration into CHP plants without affecting their performance. The primary objective of this study was to test the limits of a CHP plant with respect to retrofitting flexible thermochemical conversion of waste to drop-in biofuels with properties similar to petroleum fuels. Waste conversion to drop-in biofuels also requires significant amount of hydrogen for drop-in biofuels synthesis — Required hydrogen was also produced onsite in thermochemical processes integrated with CHP plant. The secondary objective was to determine the maximum number of days a flexible retrofitted waste-thermochemical process can run annually using only excess heat from a CHP plant, and whether such processes are profitable when operating flexibly. The results show that the selection of heat extraction points for the utilization of excess heat from the CHP plant for energy-intensive processes is critical for maintaining the flexibility of the integrated thermochemical processes. Thermochemical processes integrated with CHP plants were able to operate on approximately 180 days of the year by utilizing only excess heat from the CHP plant. Integration of pyrolysis showed more flexibility than integration of gasification. Onsite hydrogen production was the main limiting factor for the integration of thermochemical process with the existing CHP plant to produce drop-in biofuels. Hydrogen produced with a solid oxide electrolysis cell (SOEC) decreased the overall system efficiency and limited the capacity of the overall process. However, hydrogen production from a water gas shift (WGS) reactor was more expensive. The results also indicated that small changes in the financial parameters have a large impact on the economic performance of the integrated process.

中文翻译：

---

现有 CHP 工厂将插入式生物燃料的多联产与现场制氢相结合的机会和限制

摘要 在过去几年中，人们越来越关注使用新技术改造现有的热电联产 (CHP) 发电厂以联合生产其他产品。重点是设计固定规模的流程，以便在不影响其性能的情况下集成到 CHP 工厂中。本研究的主要目的是测试 CHP 工厂在将废物灵活的热化学转化改造为具有类似于石油燃料的特性的插入式生物燃料方面的限制。将废物转化为嵌入式生物燃料还需要大量氢气用于嵌入式生物燃料合成——所需的氢气也在与 CHP 工厂集成的热化学过程中现场生产。次要目标是确定灵活改造的废热化学工艺每年仅使用来自热电联产厂的余热可以运行的最大天数，以及此类工艺在灵活运行时是否有利可图。结果表明，选择热提取点以利用来自 CHP 工厂的余热用于能源密集型过程对于保持集成热化学过程的灵活性至关重要。与 CHP 工厂相结合的热化学工艺能够仅利用来自 CHP 工厂的多余热量，在一年中大约 180 天运行。热解一体化比气化一体化表现出更大的灵活性。现场制氢是将热化学工艺与现有 CHP 工厂整合以生产嵌入式生物燃料的主要限制因素。使用固体氧化物电解槽 (SOEC) 生产的氢气降低了整个系统的效率并限制了整个过程的容量。然而，从水煤气变换 (WGS) 反应器生产氢气的成本更高。结果还表明，财务参数的微小变化对集成过程的经济性能有很大影响。