I have been working on a project for several months and had intended to patent the system. Unfortunately, I am not going to be able to finish the project, so I wanted to share what I learned with the general public so others might benefit from the time I spent.
This project uses the concept of using air to "fluidize" sand so that it will flow in a pipe like a liquid. This could be useful to move sand over long distances using pipes that are much lighter than the mechanical and motorized conveyors that are typically used in this function. The major disadvantage this method presents is that it relies on gravity for motion of the fluidized sand, so, unlike mechanical conveyors, it could only be used if the end point is at a lower elevation than the beginning.
One application of this project would be to convey sand from a dump truck into the crawlspace or basement of a building to bring that elevation up so it is even with the ground on the outside of the building. In theory, this would work to convey sand over 100' if the right configuration could be found. The challenge I faced was finding the right angle and number of holes in the air supply pipe as well as the proper air supply pressure.
I have a video of the most successful configuration I was able to produce, but I have to edit it to remove personal information before I can post it. I will post it as soon as possible
There are many videos on the web dealing with fluidized sand. One of the more interesting and informative ones is here;
I simply do not have the time or the funds to keep trying to make this work, but I thought it could be an interesting project for someone to look into.
Step 1: First Attempt
In the first attempt, a section was cut out of a Schedule 40 PVC pipe. This was to allow the air pipe to be hung from the top and not penetrate the bottom so sand wouldn't fall out.
This layout has one big disadvantage because if sand starts flowing faster than the pipe can handle, it flows over the top of the pipe and makes a big mess.
NOTE: This concept requires a LOT of air. An industrial compressor that had 165CFM at 125 PSI was used to provide enough air to make this work.
Step 2: Closed Pipe, New Distribution
This photo shows a 3D model of the next step I was going to try. It has a much larger air pipe that provides air in more than one location so the pressure and flow would be distributed more evenly.
This model also uses a fully enclosed, 8" pipe instead of a sliced 6" pipe. The enlosed top should prevent the overflow seen in the first video.
Step 3: More Details on Air Pipes
Here are more detailed pictures of the model, showing the distribution of holes on the bottom of the pipe that would be inside the closed tube.
Note the use of a Chicago fitting for air connection to a 1" hose. This thing is an air hog!!
Step 4: System Concept
Here is a photo of the overall, original concept to transfer sand from a truck, through more than one pipe, to a lower point, such as a crawlspace or basement.
This could be a LOT more efficient than manually moving the sand using trolleys or wagons or lugging around mechanical conveyors that weigh hundreds of pounds.
If anyone should decide to develop this, good luck!
Just another view of a pipe assembly.