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22 © Copyright Powder & Bulk Engineering 2020 © Copyright Powder & Bulk Engineering 2020 Handling tough applications: Three examples These case histories demonstrate how the tubular chain drag conveyor can successfully handle a variety of tough materials and operating conditions. Moving ultra- ne carbon black while containing dust. An electronics company in the Southeastern US need- ed to convey an ultra-fi ne grade of carbon black to pro- cessing equipment that ran 24/7. The carbon black had to be moved from fl oor level in one room in the plant up and over obstructions to processing equipment in another room. The company knew that a pneumatic conveyor wasn't an option: Even though the pneumatic conveyor could be confi gured around the plant's exist- ing obstacles, the carbon black was so extremely fi ne that it would be virtually impossible to separate from the conveying airstream. The pneumatic conveyor's air mover would also require a lot of energy. Instead, the company searched for an enclosed mechan- ical conveyor that could provide the layout fl exibility to convey carbon black over the existing plant obstacles without releasing dust. After considering various con- veyors, the company chose a 3-inch-diameter tubular chain drag conveyor with a 2-horsepower drive motor. This conveyor now reliably conveys the ultra-fi ne car- bon black to its destination in a totally enclosed, dust- free operation. The conveyor's energy-effi ciency is an added benefi t. Removing phosphate from water. A Southern US chem- ical processor wanted a mechanical conveyor to remove phosphate from the bottom of an outdoor settling pond containing an acidic solution. The conveyor would have to withstand the highly acidic conditions at its inlet and in the surrounding atmosphere, as well as be easy to re- move so that maintenance workers could safely inspect the unit after it was moved out of the hazardous pond. The company selected a 6-inch-diameter tubular chain drag conveyor completely constructed of Type 316L stainless steel. The conveyor, which has a 3-horse- power drive motor, effectively removes the phosphate from the pond bottom while allowing the free mois- ture picked up with the solids to fl ow back down the conveyor incline to the inlet. The conveyor's stainless steel construction successfully combats the acidic at- mosphere. The conveyor also has a support frame and heavy-duty lifting eyes that allow an overhead crane to easily lift the entire unit out of the pond in one piece for periodic inspection and repairs. Elevating toxic, corrosive chemical powder to two dis- charge points. A major chemical manufacturer in the Midwestern US was using an older mechanical con- veyor to move a toxic, highly corrosive powder from a production area at fl oor level up and over equipment to two discharge points in the plant's packaging area. The conveyor's operation was unreliable, so the company looked for a conveyor that could reliably meet several requirements: The hazardous powder not only had to be completely contained during handling, but had to be blanketed under an inert gas to prevent it from reacting with air in the surrounding atmosphere. The convey- or couldn't generate a lot of fi nes, because any fi nes would require collection by dust fi lters, and this would create a toxic dust disposal problem. After considering various mechanical conveyors, the chemical manufacturer chose a 6-inch-diameter tubular chain drag conveyor with a 5-horsepower drive motor. The conveyor is supplied with nitrogen to ensure that no air from the surrounding atmosphere can leak into the conveyor. At each discharge point, the conveyor has proprietary air-actuated self-cleaning discharge gates to control the powder's discharge to processing. The con- veyor now safely and reliably moves the toxic chemical to the packaging area without releasing dust. PBE Two tubular chain drag conveyors (in blue) move incinerated paint sludge from an automotive painting operation around existing machinery and building structures.