Minimum information to be provided
1 An IMO type approval certificate should be required
for each shipboard incinerator. In order to obtain such certificate,
the incinerator should be designed and built to an IMO approved standard.
Each model should go through a specified type approval test operation
at the factory or an approved test facility, and under the responsibility
of the Administration.
2 Type approval tests should include measuring
of the following parameters:
| Max capacity
|
kW or kcal/h
kg/h of specified
waste
kg/h per burner
|
| Pilot fuel consumption
|
kg/h per burner
|
| O2 average in combustion
chamber/zone
|
%
|
| CO average in flue gas
|
mg/MJ
|
| Soot number average
|
Bacharach or ringelman Scale
|
| Combustion chamber flue gas
outlet temperature average
|
°C
|
| Amount of unburned components
in ashes
|
% by weight
|
3
Duration of test operation
| For oil residue (sludge) burning
|
6-8 hours
|
| For solid waste burning
|
6-8 hours
|
4
Fuel/waste specification for type approval
test (% by weight)
| Oil residue (sludge) consisting
of:
|
75% oil residue (sludge)
from heavy fuel oil
5% waste lubricating oil
20%
emulsified water
|
| Solid waste (class 2) consisting
of:
|
50% Food Waste
50%
rubbish Containing
Approx. 30% paper,
"
40% cardboard,
" 10% rags,
" 20% plastic
The mixture will have up to 50% moisture and 7% incombustible
solids.
|
Reference: Waste classification from Incinerator Institute
of America (information for type approval tests only).
Class 2 Refuse, consisting of approximately even
mixture of rubbish and garbage by weight. This type waste is common
to passenger ships occupancy, consisting of up to 50% moisture, 7%
incombustible solids and has a heating value of about 10,000 kJ/kg
as fired.
|
Calorific values
|
kJ/Kg
|
kcal/kg
|
| Vegetable and putrescibles
|
5,700
|
1,360
|
| Paper
|
14,300
|
3,415
|
| Rag
|
15,500
|
3,700
|
| Plastics
|
36,000
|
8,600
|
| Oil sludge
|
36,000
|
8,600
|
| Sewage sludge
|
3,000
|
716
|
|
Densities
|
kg/m3
|
|
| Paper (loose)
|
50
|
|
| Refuse (75% wet)
|
720
|
|
| Dry rubbish
|
110
|
|
| Scrap wood
|
190
|
|
| Wood sawdust
|
220
|
|
Density of loose general waste generated on board ship will
be about 130 kg/m3.
5
Required emission standards to be verified
by type approval test
| O2 in combustion
chamber
|
6 – 12%
|
| CO in flue gas maximum average
|
200 mg/MJ
|
| Soot number maximum average
|
BACHARACH 3 or RINGELMAN 1
(A higher soot number is acceptable only during very
short periods such as starting up.)
|
| Unburned components in ash
residues
|
Max 10% by Weight
|
| Combustion chamber flue gas
outlet temperature range
|
850
– 1200 °C
|
Flue gas outlet temperature and O2 content should
be measured during the combustion period, and not during the preheating
or cooling periods. For a batch loaded incinerator, it is acceptable
to carry out the type approval test by means of a single batch.
A high temperature in the actual combustion chamber/zone
is an absolute requirement in order to obtain a complete and smoke
free incineration, including that of plastic and other synthetic materials
while minimizing dioxins, VOC (Volatile Organic Compounds), and emissions.
6.1 Even with good incineration technology the
emission from an incinerator will depend on the type of material being
incinerated. If for instance a vessel has bunkered a fuel with high
sulphur content, then oil residue (sludge) from separators which is
burned in the incinerator will lead to emission of SOX.
But again, the SOX emission from the incinerator would
only amount to less than one per cent of the SOX discharged
with the exhaust from main and auxiliary engines.
6.2 Principal organic constituents (POC) cannot
be measured on a continuous basis. Specifically, there are no instruments
with provision for continuous time telemetry that measures POC, HCl,
or waste destruction efficiency, to date. These measurements can only
be made using grab sample approaches where the sample is returned
to a laboratory for analysis. In the case of organic constituents
(undestroyed wastes), the laboratory work requires considerable time
to complete. Thus, continuous emission control can only be assured
by secondary measurements.
6.3
Onboard
operation/emission control
6.3.1 For a shipboard incinerator with IMO type
approval, emission control/monitoring should be limited to the following:
-
.1 control/monitor O2 content in combustion
chamber (spot checks only; an O2 content analyser is not
required to be kept on board).
-
.2 control/monitor temperature in combustion chamber
flue gas outlet.
6.3.2 By continuous (auto) control of the incineration
process, ensure that the above-mentioned two parameters are kept within
the prescribed limits. This mode of operation will ensure that particulates
and ash residue contain only traces of organic constituents.
7
Passenger/cruise ships with incinerator
installations having a total capacity of more than 1,500 kW
7.1 On board this type of vessel, the following
conditions will probably exist:
-
.1 Generation of huge amounts of burnable waste
with a high content of plastic and synthetic materials.
-
.2 Incinerating plant with a high capacity operating
continuously over long periods.
-
.3 This type of vessel will often be operating
in very sensitive coastal areas.
7.2 In view of the fuel related emission from
a plant with such a high capacity, installation of a flue gas sea
water scrubber should be considered. This installation can perform
an efficient after-cleaning of the flue gases, thus minimizing the
content of:
-
HCI
-
SOx
-
particulate matter.