Help me with sand + plastic extruder for roof tile

hello mates,
i really commend the work everyone is doing towards promoting plastic recycling. i want to start recycling of plastic for roofing shingle and plastic lumber/pole production. i have tried locally fabricating an extruder that can melt and mix the plastic at a high temperature. my questions are what can i use as the heater and a propeller that can mix heat the plastic while having a homogenous mixture with the sand.
any other input is sincerely welcomed. am writing from Nigeria.


Hello @eokeke82
This is what I just replied on your private message:

What you want to build is totally possible, but it will be a little difficult using a extruder. In the extruder, you pour the shredded plastic into a hopper and gravity is what makes the plastic pellets fall into the extruder screw. You could install a second hopper to hold the sand, the problem is that sand is heavier and the particles are smaller than plastic, which makes sand fall faster than the plastic pellets, and it will be very difficult to make the extruder mix plastic and sand in the right proportions.

I suggest you to use a different approach, like an oven or some sort of big pot to melt the plastic and mix the sand once the plastic is fully melted, then pour the molten mix into your moulds.

Look at this video, it might give you a few ideas of what I’m taling about: