MULTIPLE EFFECT EVAPORATORS
Lundberg offers full sets of evaporators including integrated concentrator and condensate stripping systems as appropriate. The systems that we offer are designed to handle the particular nature of the liquor involved, from the easiest softwood liquor to the most difficult of liquors including bagasse and wheat straw. We provide systems for all types of cooking processes including kraft, sulfite and soda based systems. All of Lundberg’s evaporator systems are of tubular design. We consider a number of factors in the design of an evaporator system to provide the best solution for the liquor involved, including economy, scaling tendencies and desired product solids.
The liquor flow sequence for the evaporator system is designed to maximize the system steam economy and condensate segregation. The number of evaporator effects can be anywhere from five to eight effects, depending upon the customer’s needs and the technologies selected.
The heat from the condensate stripper may be recovered in the evaporator set through integration of the reflux condenser. The reflux condenser can heat inter-effect liquor, generate clean steam to drive the first effect of the evaporator or may be used as a falling film evaporator body.
Pre-evaporation systems utilize low-level waste heat to evaporate weak liquor prior to the main evaporator train. Three heat sources are most often utilized in a pre-evaporator system: heat from a blow heat system, heat from a standalone concentrator, or heat from a continuous digester extraction liquor flash tank. A Lundberg pre-evaporator can improve steam economy and/or increase evaporator capacity.