Engine exhaust gas additive storage system

Abstract

A system for storing a solution of ammonia precursor for use as an exhaust gas additive, the system including: a tank for storing the solution in a liquid state and/or a frozen state; and a freeze protection device including a cavity for a fluid, the cavity being deformable under pressure and including an exit being in fluid communication with a fluid space, the cavity being configured to discharge the fluid from the cavity into the fluid space such that an expansion of the solution upon freezing is compensated by volume reduction of the cavity under deformation of the cavity.

1 - 14 . (canceled) 
     
     
         15 . A system for storing a solution of ammonia precursor for use as an exhaust gas additive, the system comprising:
 a tank for storing the solution in a liquid state and/or a frozen state; and   a freeze protection device comprising a cavity for a fluid, the cavity being deformable under pressure and comprising an exit being in fluid communication with a fluid space, the cavity being configured to discharge the fluid from the cavity into the fluid space such that an expansion of the solution upon freezing is compensated by volume reduction of the cavity under deformation of the cavity;   a component; and   wherein the freeze protection device is configured and arranged to prevent fracture of the component under the expansion of the solution.   
     
     
         16 . The system as claimed in  claim 15 , wherein the component is a delivery module assembled to a tank surface at a bottom side of the tank. 
     
     
         17 . The system as claimed in  claim 15 , wherein the cavity is defined by at least a first wall, the cavity being deformable under deformation of the first wall or comprising elastomeric material. 
     
     
         18 . The system as claimed in  claim 15 , further comprising a means for reversing deformation of the cavity. 
     
     
         19 . The system as claimed in  claim 18 , wherein the means comprises a pump for pumping the fluid back into the cavity. 
     
     
         20 . The system as claimed in  claim 18 , wherein the means comprises a second cavity, such that the fluid leaving the deformable cavity upon expansion of the solution is transferred into the second cavity. 
     
     
         21 . The system as claimed in  claim 15 , wherein the exit extends to outside the tank. 
     
     
         22 . The system as claimed in  claim 15 , wherein the protection device comprises a venting channel defining the exit from the cavity. 
     
     
         23 . The system as claimed in  claim 22 , wherein the venting channel is assembled to the tank wall, or is assembled to the tank wall by welding. 
     
     
         24 . The system as claimed in  claim 15 , wherein the exit includes means for selective permeation of the fluid. 
     
     
         25 . The system as claimed in  claim 15 , wherein the freeze protection device further includes a connector located outside of the tank for connection of a venting tube. 
     
     
         26 . The system as claimed in  claim 15 , wherein the deformable cavity has a shape of a balloon. 
     
     
         27 . A selective catalytic reduction system for a vehicle comprising:
 a system as claimed in  claim 15 ;   an injector for injecting the solution or a reaction product thereof into exhaust gases; and   an injection line between the storage system and the injector.   
     
     
         28 . A vehicle comprising the storage system as claimed in  claim 15 .