Atmosphere Generators
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Design Features
Thermal Dynamix dissociators are generally designed for indoor installation but can be configured for outside installation and operation. The design of the Thermal Dynamix dissociator assumes a clean, dry supply of anhydrous ammonia vapor (less than 2ppm water; 2ppm oil and no sulfur) at a pressure not exceeding 35 psig and a temperature of at least 50 degrees F. We also assume the equipment is to be installed on a reasonably smooth, level and non-combustible floor. Side clearance of at least 24" should be provided for servicing and the unit should be accessible by forklift on at least one side.
The Thermal Dynamix dissociator uses a vertical retort configuration with silicon carbide heating elements. We believe this to be the best, simplest and most durable configuration; for several reasons:
1. A vertical retort ensures uniform catalyst packing density. There is no opportunity for the catalyst to settle to the bottom of a horizontal tube leaving a clear channel, free of catalyst, at the top. The absence of such a clear, open channel significantly reduces residual ammonia amounts. We normally expect residual ammonia levels, for our standard low pressure systems, to be below 50 ppm at full capacity, it is not uncommon for Thermal Dynamix standard low pressure dissociators to operate at capacity with residual ammonia at levels well below 50 ppm.
2. A vertical retort won't "sag" under load. The working temperature in the retort chamber of a dissociator is generally in the 1750F to 1900F range. At this temperature virtually any material may eventually begin to acquire a "load set" or sag between supports. Because a vertical retort is uniformly supported around its entire circumference it isn't subject to this sag. A horizontal retort will begin to exhibit a pronounced sag or "belly" as it ages under the temperatures required for it to function. A vertical retort will simply elongate as it ages and growth clearance is provided at the bottom of the Thermal Dynamix retort chamber to accommodate such growth.
3. Because a vertical retort doesn't sag but remains symmetrical as it ages, the heating of a vertical retort remains uniform over its life. When a horizontal retort begins to sag, invariably one part of the retort surface will approach, and may contact, a heating element while its opposite side will move away from its corresponding element. A vertical retort maintains its heating element clearance even as it ages.
4. We've also given a great deal of thought to accessibility. A vertical retort configuration is very convenient. Even though a Thermal Dynamix dissociator is so durable and simple that it doesn't need much service there will come a time when maintenance is necessary. To accommodate that rare event we have top mounted both the heating elements (of the electrically heated unit) and the retort. When either does need service access is quick and easy. You don't have to remove one to get to the other. A vertical retort configuration allows either a single heating element (or the whole set) to be removed and replaced without disturbing the retort or, conversely, allows the retort to be removed and replaced without disturbing the heating elements.
5. Silicon carbide elements provide greater heat density than available with metallic elements. They are more compact, easier to install and replace, less expensive and generally longer lived than metallic element systems. An added benefit, in most cases, is the elimination of an electrical transformer (although a very large dissociator may still require a transformer).
Thermal Dynamix retort chambers are surrounded by 10 inches of high performance, vacuum formed ceramic insulation. This means heat goes into the chamber and the process, not the room. The uniform density of the ceramic fiber eliminates hot spots. The shell temperature of a Thermal Dynamix dissociator is significantly cooler than others.
Thermal Dynamix dissociators are well instrumented. You don't have to guess about what's going on inside. Pressure gages on the retort(s) and heat exchanger(s) give advance warning of the need to schedule maintenance.
And finally, Thermal Dynamix dissociators are simple. The electrically heated dissociators have no pumps, motors, fans, blowers or other moving parts to wear, make noise or maintain.
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