Have been doing some digging....
In 1766 there were over 40 breweries in Dublin...
1683 - 35 ale/beer breweries in Dundalk
Ballina Chronicle 10/04/1850 there were 96 licensed brewer's in Ireland....{must have been alot of unregistered ones}..
Up in the North earliest recorded was:
1777 - James Higginson Brewery in Lisburn
Brewing was carried on fairly extensively in 1850's throughout the Norther but gave way in the end to Buy outs and distillery's.
1850's - Belfast
Lewers Brewery, Anne Street
Messrs Mackenzie Shaw & Co's Brewery, Hercules Street (now Royal Ave)
Messrs Clothworthy & Dobbin Brewery, Smithfield
Messrs Henry Scott & Co's Brewery, Cormac Street
Messrs Fordyce & Co's Brewery, Cromac Street
Mr Johnson's Brewery, King Street
Mr Henry Murney's Brewery, Bank Lane
Mr John Kane's Brewery, North Street
1867/1869 Changed name in 1883, building still in use 1901...
Belfast & Ulster Brewing Company, Sandy Row
1897 - Ulster Brewery (Thomas R Caffery) owned by Caffery family until 1950.
Outside of Belfast:
Unknown - 1 in Comber
John Johnston - 2 in Lurgan,1 in Antrim, 1 in Newtownards. Circa 1840ish still operating in Lurgan in 1910.
John Boyd & Samuel Watts - Boyd & Watts 1840 in Lurgan. Watts left an endowment in his will in 1847 which built Lurgan College in 1873. CS Lewis's father Albert was educated there..bit of trivia..
Robert Ruddock - Waringstown 1824
Breweries around the same time in Moira, Hillsborough and Magheralin.
Lisburn - William Graham
Downpatrick - (2) Saul's & Moore's
Derry - (2) Carson's & Meehan
Desertmartin/Limavady - Edward Kelly
Ballymoney - Janes Colgan
Donaghmore - Lyles
Newry - (2) William Henry & Co and Mr Arthur Russell
Enniskillen - Unknown
Hope this is of some help...hope to find out more in the Irish library in Armagh..will keep you posted!