Mohtogh:

Part of the answer you seek is based upon the type of acid you want to scrub.  Also, do you want to recover the acid?  This may a very real possibility, depending upon the type of plant and type of acid.  This answer alone can often resolve your initial question.   

How big is the storage tank?  What type of turnover are you looking at?  Does the tank require 24/7 vent service?  Or periodic service during filling?  The tank turnover requirement should be well documented since that determines overall system size, which determines footprint, weights, etc. all of which are important in determining the feasibility of either solution.

What regulatory limits or process requirements are you trying to meet?  The required control efficiency may eliminate certain technologies, though this is doubtful.  

Generally speaking, either technology can be made to work.  Acid vent scrubbing is not rocket science.  With wet systems, you would normally use an alkali reagent and pH control, with level controls on the sump.  Therefore, you have a scrubber vessel (usually with an integral sump), a reagent tank (size depends on process characteristics and how frequently you want to replenish reagent) and a simple pH/level control panel.  All of this can be tied into process control systems very easily for process control and/or environmental monitoring and reporting.  Which raises another question, will you be required to monitor the unit and report operating or control history to regulatory agencies?  

If your plant has a large waste water treatment plant and water conservation is not a prerequisite, I have seen once through scrubbers using waste process waters from other operations without neutralization in certain applications, though I don't generally recommend this approach.  Thisis very process specific, but can assist the economics, especially if the waste stream is alkaline.

The dry systems work well, but require replacement of the scrubbing media over time.  How's your plant maintenance record?  Wet systems require maintenance as well, so this question doesn't by itself assist greatly in selection I know, but if maintenance is generally slack, then I would recommend the dry system as it has a lower frequency of  maintenance requirements.   

Also take a look at potential waste products and their disposal.  There can be hidden surprises here sometimes, so it pays to check it out even when it first appears to be a no-brainer.  Good luck!  

Finally, once much of the above has been adequately defined, you must take a look at the operating costs.  I would recommend that you gather the data you need for the above analysis and then contact either vendors or a consultant to assist you as needed to answer these questions.  

Thank you Fizzhead

Try looking at the Chlorine Institute website.