Healthcare waste management in developing countries
Practical Action
Figure 1: Representation of Mark 8a De
Montfort (WHO et al., 2005)
The ‘De Montfort’ incinerator has the capacity
to destroy any medical or domestic waste,
which is combustible. However, it should only
be used to destroy sharps (including syringes
with needles attached, razor blades, scalpels
and any other sharp objects which may be
contaminated, like glass, but excluding vials or
ampoules), infectious non-sharp waste (like
tissues and materials, or equipment which has
been in contact with blood or body fluids,
including swabs, bandages and any other waste
which may be contaminated) and non-
infectious waste (just if it cannot be
transported to a municipal waste disposal
facility or if no alternative environmentally
sound solution for disposal is available). On the
contrary, the ‘De Montfort’ should not be used
to destroy waste containing broken
thermometers, fluid bags, PVC plastic bags,
closed glass, vials and ampoules or wet waste.
Box A summarizes what De Montfort’
incinerator can and cannot do.
Box A: What De Montfort incinerator does and what it does not do
Does:
It reduces all waste added to ash and flue gases. This includes dressings, wet or dry, plastics,
organic matter, etc. Used hypodermics can be added, but needles may not all be reduced
though they will be sterilised and denatured. Care should be taken when removing ashes in
this case. Small glass sharps will normally be part melted and rendered safe. When properly
operated, the flue gases emitted will have been held at a high temperature (800°C) for at
least one second and should be almost harmless.
Does not do:
It will not render all flue gases smoke free and will not meet clean air requirements in all
situations with all loads. If this is your requirement, you will need to buy a much more
expensive incinerator and have it professionally installed and operated. It will not operate
automatically without attention. When burning waste, particularly infectious waste, an
operator must be in constant attendance. It is not suitable for short sharp burns with no
warm up period. For this sort of operation you need a low thermal capacity incinerator,
probably made of stainless steel and gas heated. It is not suitable for operation in a closed
room. Smoke will be emitted whenever the loading door is opened. A roof may be fitted to
protect the operator from rain, but only minimum walls.
De Montfort University has developed different models of incinerator (Picken, 2007). They are
all variations of the same basic design, namely the Mark 1 incinerator. It can burn 12 kg/h of
waste and it has now been superseded by the Mark 8a, which is more robust and reliable and
cheaper to build.
The various models are characterized by different designs and/or capacities. Table 4 shows a
brief overview of the main characteristics of the available models.
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