It is illegal, and probably antisocial, to burn your rubbish in republic of Ireland. Dont know what the situation is in the north.
When I'm traveling in the van I dump rubbish regularly, when it is still a small quantity, in street rubbish bins or bins at shops. These bins generally have a bar preventing you from putting a large rubbish bag into them and hence the need to dump regularly. You are buying your rubbish in the shops so I dont see why you shouldn't use their bins, regardless of who is looking.
There are plenty of recycling centres around the country. Free bins in most villages or town for glass, pay centres in most big towns if for other recyclable material. Any shop will direct you to them.
If you have a large amount of non recyclable rubbish, there are 2 options. Every town has a bin day and you can generally just buy a bag in local shops for the local bin company. The shops would again be able to advise you on which day is bin day and you just need to leave bag beside any other bag left out on that day.
If its not bin day, most of the pay recycling centres will also take bags of rubbish for a charge.
Be warned getting rid of rubbish here is expensive so dumping little but often is probably advisable. Local centre in Sligo charge €5 per black bag of rubbish.