There are obviously many different types of incinerator designs such as static hearth, rotary kiln, moving hearth, stepped hearth, bogie hearth and others.

In this blog we are going to talk about different options available in static hearth designs:

• Grated hearth

In this design, the hearth has grate bars and it is meant for solid wastes.  The grates allow movement of the flue gases from the primary chamber to exit through the chimney via secondary burning by the same burner.  This is a very good and effective design and is used by many customers for applications such as medical waste, general garbage, food waste, paper and packaging waste and so on.

• No separate hearth

If the shape of the incinerator primary chamber is cylindrical, the bottom semi-circle will be used as a hearth.  This is used in our models PDR, ADR, PWR, etc.

• Dual hearth

This is especially provided for animal waste cremators where the animal waste is loaded on the main hearth, below which a secondary hearth is provided for burning the fat that is released while animal waste is being incinerated.  This is a very special design and is quite efficient as it prevents leakage of any liquid fat from the system without burning.

• Under hearth

This design is used both with bogies as well as static models.  The purpose of the under hearth is to enable the flame from below the hearth to come through orifices and burn the waste loaded either in special trays (used by the precious metal industry) or to provide complete combustion for certain difficult materials. This enables indirect heating and prevents precious metal dust fly-off.

• Jacketed hearth

Where the specifications call for room temperature on the skin of the incinerator, this calls for a jacketed design through which cooling air is continuously forced to bring down the skin temperature within limits.  This is especially used in our SWR model which is used on board ships.

• Honeycomb design

A series of honeycomb structures which is the hearth of the regenerative thermal oxidizer provides a self-sustaining system where the honeycombs allow cold waste gas to pass through one bed and heated by a burner subsequently, which results in the hot flue gas releasing this high heat to another cold bed, making it hot in the process.  This operation is reversed every few minutes so that the cold honeycomb bed is repeatedly heated by the outgoing flue gas at high temperature and the hot honeycomb bed raises the temperature of the incoming gas.  This reduces the cost of running the system to practically nothing as the burner operates based on the chamber temperature and is not run on a continuous basis.

All the above designs are available with Haat having supplied quite a few of these incinerators successfully over a period of time to the satisfaction of the end users.