VacuDry Working Principle Brochure

Process and design
At the core of the econ industries VacuDry® process is a bespoke dryer chamber which uses heat and controlled vacuum to evaporate volatile contaminants. The batch-wise working indirectly heated thermal desorption process treats solids contaminated with mercury, hydrocarbons, solvents and other hazardous substances at temperatures above their boiling points. To heat up the dryer a temperature resistant synthetic oil is circulated inside the dryer`s heating jacket and its central shaft. The rotating shaft ensures intensive mixing during the process, guarantees a highly-efficient heat transfer to the product and allows short, energy-saving batch times. After vaporisation the exhaust stream is led through a highly effective vapour filter unit to prevent dust merging with the vapours. Specially designed heat exchangers separate the vaporised contaminants from the main vapour stream by condensation using indirect cooling. For the individual recovery of valuable substances gradual heating assures their defined separation. The remaining vapour passes through a powerful vacuum unit and is cleaned of residual contaminants via an active charcoal filter before finally being led off into the atmosphere. The treated, dried solid residues - usually > 99 % pure minerals - are cooled and remoistened. An additional small mixer is used for later re-moistening or solidification where required. Various feeding systems are available, depending on the consistency and type of the input materials - varying from liquid sludge up to soils/debris of all types of contamination levels.