Wow, that Kanza really is an amazing combination of ignorance & arrogance! Of course you don't create dry ice in your lungs! The gases in your lungs are at the same pressure as the surrounding atmosphere - they have to be because the space in your lungs is directly connected (via your nose & mouth) to the outside world - that's how the gases get in and out as your ribs/diaphragm expand & compress your lungs.
An average human breathes some 10 times per minute, 600 times per hour, or 14,400 times per day. If we assume that each breath contains one liter of air, then simply human inhales some 14,400 liters of per day. Air is composed of about 16% oxygen, of which about half is exchanged for carbon dioxide during each breath. Then this means an average exhalation of some 14,400 x 8% = 1150 liters of carbon dioxide per person per day.