I won't say, that the circuit is particularly terrible. It's completely unclear. Assuming the said 24 V is a controlling voltage, what's the purpose of the 12V supply? Where is the said 230V circuit?
You can use a triac as simple switch, if
- you don't need isolation between the control circuit and the 230V circuit. Connecting the control circuit to the triac directly means,
that it's becoming part of the high voltage circuit, that must be protected by safe isolation.
- if the load is AC, not DC
- if you provide a sufficient heatsink for the triac power dissipation at 10 A
- if the load isn't inductive, otherwise you need snubber additional circuits
- if you're sure, that no inrush currents can damage the triac
Considering the short list of restrictions (there are probably some more), it can be a good idea to use a mechanical relay. Most
home appliances actually do for high current switching, if the switching frequency is moderate.
To comment another post. Zero cross switching is not absolutely required, unless switching very often. A relay also doesn't use zero
cross switching. But's it's desirable of course, and can be simply achieved in many cases. With inductive load, it's generally unwanted, in contrast.