Posted by: etwombly on Aug 10, 2010
Tagged in: news
Issues with Airlock
We have been working on testing the airlock we have been trying to get to work on the cyclone which is inside the reactor hotbox.
So far we have tested several types of bushings and drive rods. The way we make the airlock work is there is an airlock with 6 fins inline below the cyclone. Those are turned at a slow speed of less than 10 rpm. The fins are on a shaft which extend outside the hotbox.
The area we are having problems with are the bushings where the drive shaft goes into the side of the airlock. These bushing have damaged the surfaces when run at the 600 degree C temperatures in the hotbox. We have tested bushings of brass, oil impregnated brass and carbide. All have either deteriorated or deteriorated the drive shaft made of steel or stainless steel.
We are continuing to test various bushing metals and hope to solve this problem soon.
Fall back plan will be tested next.
The is a second form of airlock that can be used with a cyclone. This is to put a relatively airtight container on the bottom pipe. This requires no moving parts so last week we built a long tube that runs below the cyclone that will run through a hole in the bottom of the reactor. This tube will have a ball valve in line, there will be a 5 gallon paint can on the tube below the valve with the lid sealed onto the tube and clamps to hold the can in place. The valve can be turned off to remove the 5 gallon paint can and dump the char collected in it as needed.
There are some issues with this method. The most difficult is that the char will not be cooled in the normal way, so the char collect in the paint can will be above the kindling temperature of char. So if the char is left exposed to oxygen it will burn. The char will be dumped into another airtight container so it can cool in contact to minimal oxygen.
This method is not the most desirable but if successful will be used to run longer hours till we can resolve the primary airlock solution.
Renewing DEQ Air Quality Permit
Our letter to permit us to run without air quality testing has expired. We have had a test on our plant which parts per million of various air pollutants. There is also a test done on a similar plant in Canada. We have the results of both. In order to finalize the report for DEQ we need to be able to document tons of each pollutant per year. So in order to know this we need air flow rates during operations, we are now waiting for this information from ABRI to complete the DEQ report.
To be clear we seem to not actually need a permit. As I understand it, as long as we are below specified levels the permit is not required. We need to prove this fact .