What to check on a Incinerator.
An incinerator destroys waste by burning it in a refractory-lined chamber at high temperature, reducing sludge and solid garbage to ash and flue gas, rather than separating or filtering it the way a bilge water separator or sludge tank does. It is the endpoint for oily residues and combustible solid waste that cannot be legally discharged or that the ship has no room to keep for shore delivery, and it is one of the most closely inspected pieces of equipment in a port state control examination.
What sets the incinerator apart
An incinerator destroys waste by burning it in a refractory-lined chamber at high temperature, reducing sludge and solid garbage to ash and flue gas, rather than separating or filtering it the way a bilge water separator or sludge tank does. It is the endpoint for oily residues and combustible solid waste that cannot be legally discharged or that the ship has no room to keep for shore delivery, and it is one of the most closely inspected pieces of equipment in a port state control examination.
Main components
Combustion chamber
A refractory-brick or castable-lined steel chamber built to withstand sustained high temperature, sized as either a single chamber for waste oil and sludge only, or a two-chamber design that also takes solid garbage through a separate loading door.
Burner and feed system
A waste-oil burner atomizes preheated sludge and waste oil into the chamber; a dedicated feed pump and heater condition the sludge so it flows and atomizes properly, since raw sludge straight from the purifier is usually too viscous and too wet to burn cleanly.
Air supply and flue
A forced-draught fan supplies combustion air, and a flue with a spark arrestor carries hot exhaust gas clear of the deck; some installations recover flue heat for other services.
Control and interlocks
A control panel monitors chamber temperature, flame presence and door position, shutting the burner down automatically on flame failure, over-temperature or an open loading door.
Selection and sizing
- Burning capacity, rated in kg/h for solid waste and litres per hour for oil, sized against the ship's actual sludge and garbage generation rate rather than a generic figure.
- Oil-only units suit ships whose main waste stream is sludge and waste oil; combined units add a solid waste chamber for garbage.
- Automatic sludge burning, feeding directly from the sludge tank on a timer or level control, reduces manual handling compared with batch burning.
Regulations and class
MARPOL Annex VI Regulation 16 governs shipboard incinerators, requiring type approval to the applicable IMO standard and prohibiting the burning of items such as PCB-containing materials, PVC-containing garbage, and heavy-metal-bearing residues. Approved incinerators operate within specified flue gas outlet temperature ranges, and every burn is logged in the Garbage Record Book and Oil Record Book Part II. Many ports restrict or prohibit incinerator operation while alongside.
Typical faults
| Fault | Cause | Consequence |
|---|---|---|
| Burner nozzle coking | Sludge with too high a water content or poor pre-heating | Incomplete combustion, visible smoke, possible failed emissions check |
| Refractory cracking | Repeated fast heating and cooling cycles | Hot spots on the outer casing, structural damage over time |
| Sludge pump air lock | Excess water or air entrainment in the feed line | Loss of flame, automatic shutdown mid-burn |
| Flue blockage | Soot and unburned residue accumulation | Back pressure in the chamber, trips on the safety interlock |
What to look for in a supplier
- A type-approval certificate matching MARPOL Annex VI requirements for the intended flag and trading pattern.
- Ability to burn the sludge water content the ship's separators actually produce, not just clean test-bench oil.
- Spares for burner nozzle, igniter and control interlocks.
Sludge that still carries significant water never burns cleanly — dewatering it properly before it reaches the burner does more for a clean stack than any nozzle adjustment.