Patent ID: 6984311

Claim:
A method of mixing fluids in a fluid-solid contacting chamber, the method comprising: a) withdrawing an effluent from a first bed containing particulate solids in a fluid-solid contacting chamber, and passing said effluent into an interbed space within said chamber, wherein said interbed space is defined in part by said first bed and the wall of said contacting chamber; b) passing a first quench fluid into an inlet end of a first quench conduit, and discharging the first quench fluid from an outlet end of said first quench conduit into said interbed space at a first flow rate; c) after said passing at said first flow rate in b), decreasing the flow rate of said first quench fluid to a second flow rate that is less than said first flow rate; d) after said passing at said first flow rate in b), passing a second quench fluid into an inlet end of a second quench conduit, and discharging said second quench fluid from an outlet end of said second quench conduit at a third flow rate, wherein the wall of said first quench conduit and the wall of said second quench conduit define an interconduit space, wherein said second quench fluid passes through said interconduit space, and wherein said third flow rate is less than said first flow rate; e) after said passing at said third flow rate in d), decreasing the flow rate of said second quench fluid to a fourth flow rate that is less than said third flow rate; f) contacting said effluent with at least one of said first quench fluid and said second quench fluid in said interbed space to produce a mixture; and g) passing said mixture to a second bed containing particulate solids in said fluid-solid contacting chamber.