Explosion proof design in wet granulation

Smouldering explosion refers to the technology that the explosive mixture that can be ignited is enclosed in the equipment, and the equipment can bear the explosion pressure of the internal explosive mixture and prevent the explosion from spreading around The structure strength and flameproof performance of the equipment are mainly investigated The equipment shell is the object to bear the explosive force, so it becomes the representative of the strength of the explosion proof equipment The equipment shell is generally composed of several connectors The joint between the connector and the connector will inevitably leave a joint gap In order to prevent the explosion inside the shell from spreading to the outside, the strength of the equipment shell, the length, clearance and roughness of the joint surface must meet the requirements The reason why it can play a role of smothering explosion is that the equipment shell covers the explosion through its strength, so that the explosion inside the equipment will not be transmitted to the outside, thus reducing the loss caused by the explosion (1) the main function of the structural strength explosion proof equipment is to limit the internal explosion within the equipment, so the equipment shell or its connection part must have sufficient structural strength to withstand the explosion pressure generated during the explosion For this reason, both the wet granulator and the fluidized bed adopt the design principle of pressure vessel The fuselage is made of stainless steel plate with a certain thickness, and the top of the fluidized bed adopts an elliptical head, which is not only convenient for processing, but also favorable for stress, so as to ensure the strength of the equipment wall The explosion-proof closure design is adopted at the connection part, which greatly increases the pressure of the connection part of the vessel through the engagement of the two parts of the closure device Structure strength: when the explosion occurs inside the equipment, the explosion-proof buckle can bear the explosion force, prevent the parts from separating under the explosion pressure, so as to keep the equipment in the original state All of these measures effectively increase the structural strength of the equipment, so as to ensure reliable explosion proof performance (2) leakproofness: good leakproofness is also an important aspect of explosion proof design The wet granulator and the fluidized bed are sealed by air bags Air bags are added in the grooves of the connecting parts The air bags are in the state of inflation when they are working The inside and outside of the container are well isolated to prevent the pressure, flame and explosion products from spreading outward when explosion occurs Wet process grain line is a system, so in addition to the equipment's own explosion suppression design, the effective isolation between process units should also be considered, so as to limit the explosion within a certain range, prevent the explosion from spreading between equipment, and cause systematic damage In order to prevent the internal explosion of the equipment from spreading to the upstream or downstream equipment through the pipeline, resulting in greater loss, the fluidized bed is equipped with an explosion-proof valve in the two pipelines of the air inlet and the air exhaust The function of the flameproof valve is to prevent the explosion from spreading from the initial position to other process units, so as to avoid secondary explosion or system explosion accidents The explosion-proof valve has passed ATEX certification, which is divided into one-way explosion-proof and two-way explosion-proof It has good internal aerodynamic structure and smooth internal surface, and can start quickly When the explosion occurs, the pressure in the equipment increases, and the wind speed through the explosion-proof valve suddenly increases, exceeding the limit wind speed The internal valve core moves in the same direction with the explosion direction, so as to block the pipeline, block the explosion flame and pressure, and prevent the explosion from spreading through the pipeline As shown in the figure is the fluidized bed equipment in the state of explosion suppression At this time, the valve core of the explosion-proof valve acts and moves to its closed position to limit the explosion in the fluidized bed equipment to ensure effective explosion suppression.