"All burnt-offerings of the sanctuary were burned upon the brazen altar. The fire was kindled by the Lord Himself, (Lev. 9:24) and was kept burning continually. It was never to go out. (Lev. 6:13) The fire which destroys all sin from the earth, like the fire on the brazen altar, will come down from God out of heaven, and will not be quenched as long as there is any sin to be consumed. (Rev. 20:9, Mark 9:43-48)
The entire body of the whole burnt-offering and portions of various offerings were burned upon this brazen altar. It consumed that which typified sin; and as the fires were continually burning, it has been called "the altar of continual atonement." Sin separates man from God, (Isa. 59:2) and all sin must be put away before the sinner can be at-one-ment with God. Therefore the work done upon this altar was a symbol of the final destruction of sin, which will be necessary before the redeemed can enjoy their eternal inheritance. Paul referred, to this altar as a type of Christ. (Heb. 13:10) All the work connected with the altar of burnt-offering typified the work connected with the destruction of sin,–a work which Christ alone can do. The Father has delivered into the hands of His Son the final destruction of sin and sinners. (Ps. 2:7-9)"
- The Cross and its Shadow by Stephen Haskell
I tend to agree with his conclusion about it representing the destruction of sin and the wicked by fire.