Filter cake often plugs inlets and builds up inside of hammer mills and feeders. It puts workers lives at risk, particularly when these inlets must be manually cleaned, letting oxygen into chambers filled with coal dust. Useful BTUs are contained within filter cake, which makes it economically wise to recycle filter cake to burn in the furnace.


The traditional technique of drying out filter cake is that of a bygone era. Yet, this method is the most common way and is regularly used today. Filter cake is dumped and spread across a field where it’s left to dry in the sun. Periodically, the material is flipped to facilitate drying. Rainfall sets this process back and increases drying time. Drying can take 6 months or more and the process involves considerable handling.


Our process revolutionizes filter-cake processing, turning an outdated process into a model of efficiency. ZMax is mixed and blended with coal filter cake, using a COALCAKEpug pugmill system by ZorbsMORE. Filter cake is very clumpy as it discharges from the coal plant. Our process allows for a steady stream of filter-cake to feed into the pugmill at a continuous rate. 

One of our coal fired power plant customers who has filter cake at 37% moisture, successfully uses ZMAX at the minuscule rate of 1 gram ZMAX to one pound of filter cake! That is only 4 lbs of ZMAX to 1 ton of filter cake. They are savings thousands in processing cost alone.

Additive is precisely metered into the pugmill, where the materials are blended and mixed. The finished product has a particle size of approximately ¼” minus (6.35mm). Processed material is round and granular in shape. The mixture is ‘airy’, whereby a shovel can be effortless inserted into the pile and scooped up. We’ve seen a rate as high 70 tons/hour! Air-voids between the particles are visually noticeable, further enhancing airflow and drying. ZMax continues to absorb moisture, post production. If so desired, material can be further reduced in size with the adaption of our blender, fixed at the pugmill discharge. This gives rise to the potential of pneumatically reintroducing coal filter-cake back into the furnace.

Coal Filter Cake BEFORE - Coal Filter Cake AFTER ZMAX