Incinerator

Incinerators are colossal, city block-wide sized, machines built by Buy n Large corporation. They are seen briefly in the movie WALL-E.

Function
Incinerators were used to get rid of the trash that had overwhelmed the Earth by 2105 due to mass consumerism. Incinerators were cleaning the earth with small trash compactor robots called WALL-Es.

Incinerators move on big tank treads and have a separate crane units in front of them that slices the trash towers that WALL•Es have built into digestible sections for the incinerators. Incinerators then incinerated the trash away.

WALL-E
The incinerators and their cranes were seen towering over the city buildings when WALL-E was heading home from work. All of the incinerators and their cranes were standing still because they had ceased functioning long ago.