In processes such as Chemical Looping Combustion with high operating temperatures, the solid circulation control with mechanical valves would result in complex technologies and significant cost. Non-mechanical devices such as L-valves represent simple, cheap and reliable means to control the solid circulation rate around the flow loops. However, their design, especially for large units, must take into account the operating conditions such as particle properties, pressure profile and solid circulation rate in order to be able to control the flow in the range of operation.
In this work, a parametric study has been performed in order to study the effect of operating conditions on the design and operability of L-valves. The importance of pressure balance, solid flowrate and particle physical properties has been investigated and suggestions for providing a flexible design have been made.