S-Load® is a technology developed and patented by Petroval, for the loading of inert support balls into the bottom of a reactor quickly, safely and without breakage. The S-Load® process is far superior to alternative technologies, as the equipment is easy to install and compact to transport even to remote locations. The process is highly compatible with the loading of the main catalyst beds.
THE MAIN PROBLEM ENCOUNTERED WHEN LOADING INERT BALLS IS BREAKAGE.
Due to their shape and weight, inert support balls have an inherently high terminal velocity (Vt), close to 40 m/s for 1” (25 mm) balls and only somewhat lower for smaller balls. A free fall over any appreciable distance, e.g. more than five meters, results in the balls achieving a very high falling velocity, thus causing breakage on impact in the bottom of the reactor which can lead to high reactor delta P.
PETROVAL'S SOLUTION : INDUCING AN UP-FLOW OF AIR INSIDE THE TUBE.
In order to avoid this problem, the S-Load® technology manages to reduce the falling velocity of the balls by the simple process of inducing an up-flow of air inside the tube used to load the balls. A special Y-type connector is connecting the top of this tube to the outlet of the top hopper. For the tube leading into the reactor, a rigid pipe or semi-rigid hose (e.g. a standard vacuum hose) is used. The use of this type of tube is already prescribed, for safety reasons, for the loading of the main catalyst beds.
A vacuum system, which is usually already available on site as part of the whole catalyst change-out job, is connected to the side outlet of the Y-connector. Consequently an up-flow of air is created inside the loading tube, which slows down the balls as they free fall inside this tube. By regulating the rate of the air flow, the velocity of the failing balls can be controlled in order to get an impact velocity around 5m/s.
As noted above, in most cases the same tube as the one used for the balls loading will also be used for the catalyst loading. Once the loading of the balls has been completed, the up-flowing air flow is stopped. The catalyst can then flow from the hopper, through the S-Load® Y-component into the tube. If additional balls loading are required later on, the air flow is simply re-established.