| 摘要 |
[PROBLEM] To provide a valuable substance recovery device, etc. that can keep equipment costs and operation costs low and can reduce a burden of gas processing after secondary combustion. [SOLUTION] A valuable substance recovery device 1 provided with a calcining furnace 11 that is attached to a cement firing device 2 and a return path 12 for returning an exhaust gas from the calcining furnace to the cement firing device. By effectively utilizing heat generated by the cement firing device in the calcining furnace for recovering valuable substances, equipment for supplying fuel for the calcining furnace becomes unnecessary and operation costs can be kept low. Acidic gases can be processed using a large amount of CaO present inside the cement firing device, making special processing device for processing the acidic gases unnecessary and making it possible to reduce equipment costs and operation costs significantly compared to the past. The calcining furnace is able to take in heat from a lower portion thereof and discharge the same from the return path, and can return the calcining furnace exhaust gas to an 800°C or higher temperature region of the cement firing device via the return path. |
