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Show Some of the solutions used to overcome these problems were: Increasing the weight of combustibles fed per hour by adding non-combustibles such as soil and metals to absorb the heat generated. Excess water in the feed can be relieved by using small amounts of light weight absorbants such as vermiculite which eliminates the sticking of the muddy material while adding little in throughput weight. The slagging of the kiln walls can be reduced by lowering the temperature within the kiln to near the low operating limits (1400-1450 0 F) specified in the permits. The introduction of inert materials such as soil and metals (from cut up drums) causes the local temperatures of the incinerated material to be lowered and reduces the tendency of it to stick to the walls decreasing the rate of slag buildup. The major lesson learned from these experiences is that during processing of large quantities of soil, the trash generated during the system operation should be processed simultaneously instead of being set aside for later processing. Soil containing a small fraction of plastic, trash, etc. is far easier to process than trash alone. o Feed System Problems The feed system for the MIS consists of four pieces of equipment: a slow-speed high-torque shredder, a belt conveyor, a batch-type weigh scale, and a hydraulic ram. Each piece of equipment can cause feed interruptions depending upon the feed material consistency and characteristics. The shredder prepares most materials for feeding extremely well. However, wooden pallets and metal drum closure rings, may cause feed blockages when shredded in the present equipment. While most of the wooden pallet is broken into 2-inch wood chips, an occasional board will position itself to go through the shredder as a two inches wide by four feet long sliver. The same is true for the drum lid rings. The shredder sometimes drags the ring through, straightening it but not cutting it. In each case, plugging of the conveyor, weigh scale, or ram then follows. The only solution has been to manually remove the long slivers and put them back through the shredder. An active classifier below the shredder may provide a more suitable solution. The conveyor has caused several problems. The "flexibelt" vertical sided belt is loaded from a hopper underneath the shredder. To keep the shredded material from spillingover the belt, a restricting dam is required to level the granular material as the belt exits the shredder hopper. While this |