What are modern incinerator furnace walls typically lined with?

Modern incinerator furnace walls are typically lined with materials designed to withstand extremely high temperatures and to promote efficient combustion. The correct choice indicates that these walls are often lined with tile or have water walls.

Tile lining is advantageous because it can effectively absorb some of the heat and provide insulation, while also withstanding the corrosive environment inside an incinerator. Water walls, which consist of a series of pipes filled with water, serve a dual purpose: they provide cooling for the furnace walls and also generate steam, which can be harnessed for energy recovery processes such as cogeneration. This design helps in maintaining structural integrity under intense heat and also aids in energy efficiency.

In contrast, the other materials listed in the incorrect options may not effectively serve the specific needs of high-temperature environments in incineration processes. For instance, plastic would likely melt and degrade in the extreme heat, while steel alone may not provide adequate thermal insulation or could warp under high temperatures. Brick with fire-rods may be useful in some furnaces, but they do not represent the modern practices which prioritize efficiency and durability through advanced lining technologies.