Can I use Compositor to colorize image? I often need to change color of a texture to create differently colored models. Usually I do it in Photoshop by selecting "Colorize" checkbox in Hue/Saturation and then modifying the Hue. Is there a way to achieve similar effect with Compositor in Blender? There is a Hue/Saturation node, but it does not have "Colorize" option. It would be great to use 32 bit EXR files directly.
Yes.

Try using a mix node with the blend mode set to Color: