We like the #17 but there is too much background color. The intry #10 was too simple.
#39 and #45 we like the factory but not the chimneys. The rainbow is too much "my little pony" :-) But there should be something there instead... It makes a more complete logo. But in general fewer colors.
Maybe this could inspire you:
http://www.socialistunity.com/wp-content/uploads/2007/09/chimney-plate-10cm.jpgWe like the japanese style sun... it is simple and cool... like a fashion brand...