Operation of a dual fluidized bed, consisting of a riser as combustor and bubbling bed as gasifier, for synthesis gas production from a solid fuel requires determination of the solids circulation rate and char transfer rate. The performance relies on supplying sufficient heat from the combustor to the gasifier by circulation of solids between these two reactors. The flow rate of char is required to track the heat generated in the combustor, which supports endothermic reactions in the gasifier. Direct measurement of these two critical parameters is difficult, with the number of reported techniques capable of working at high temperatures extremely small. An indirect method was developed, using mass and energy balances over the entire system and individual reactors, to estimate the solids circulation rate and char transfer rate. There was general agreement between heat losses estimated from energy-balance calculations and from direct measurement of the outer reactor surface temperature. Under typical gasification conditions, the solids circulation fluxes were estimated to be 45.2 and 55.6 kg/(m² s) in two independent tests, which were in good agreement with values obtained using a thermal tracer; char transfer rates were calculated to be 1.2 and 0.6 kg/h, which were in reasonable agreement with average biomass feed rates. This method can be applied to dual gasification systems at any temperature or flow rate.

为了由固体燃料生产合成气，由提升器作为燃烧器和鼓泡床作为气化器组成的双流化床的操作需要确定固体循环速率和焦炭转移速率。该性能取决于通过这两个反应器之间的固体循环从燃烧器向气化器提供足够的热量。炭的流速需要用来追踪燃烧器中产生的热量，从而支持气化炉中的吸热反应。直接测量这两个关键参数是困难的，报告的能够在高温下工作的技术数量非常少。开发了一种间接方法，使用整个系统和各个反应器的质量和能量平衡，以估算固体循环速率和焦炭转移速率。在通过能量平衡计算估算出的热损失与直接测量反应堆外部表面温度之间的热损失之间达成了普遍共识。在典型的气化条件下，固体循环通量估计为45.2和55.6 kg /（m²  s）在两个独立的测试中，这些测试与使用热示踪剂获得的值非常吻合；炭的传输速率经计算为1.2和0.6 kg / h，这与平均生物质进料速率合理地吻合。该方法可以在任何温度或流速下应用于双重气化系统。