Those blue pieces of equipment might be boilers. I asked chat GPT if it could identify them and here is what it said.

Yes, the blue pieces of machinery in the image are industrial fire-tube boilers.

Key Identifiers:

• Cylindrical horizontal shell: Characteristic of fire-tube boilers.
• Front-end combustion chamber: The open door with multiple small holes is the tube sheet, where hot combustion gases pass through tubes surrounded by water.
• Pressure gauges on top: Indicate internal boiler pressure.
• Burner assembly at the front: Where fuel and air are mixed and ignited.
• Steam/water piping and insulation: Visible throughout the boiler room.

Function:
Fire-tube boilers are used to generate steam or hot water for industrial processes, space heating, or power generation. In this type of boiler, hot gases from combustion travel through tubes that run through a water-filled drum, transferring heat to the water.