Sterilization time: approx. 30 minutes at 121◦C/1.1 Bar or approx 15 minutes at 132◦C/2.5 Bar to achieve 6log10
sterility
Fragmentation inside the chamber: Heavy duty with maximum size of final product <20 cm.
Volume reduction of the waste after processing : by 60-80% through complete waste dehydration including liquid
content of the waste
All actions after loading for sterilization, fragmentation of product is to be occurred in the same chamber/vessel
Pre or Post-air evacuation should not be necessary or used
Exhaust air quality : Does not require any venting for odor control
Operating System: Fully automated with manual over-ride .(On board PLC capable of generating written report with
cycle time , cumulated time at >121◦C
The option should be there for Internet connectivity by phone, cable or
Boiler : should not require pre-heated water
Electrical requirements: 220Vac, 1ph or 400vac 3ph to suit customer needs
Noise level at full operation: <80 dB
Working Principle of the processor
The processor should utilize steam technology in conjunction with a mechanical fragment (grinder) to sterilize
medical waste, thereby making the residual waste safe for disposal in landfills.
The sterilization vessel MUST be a double walled (jacketed) cylindrical vessel.
Pre-shredding of infectious waste must not be accepted, the fragmentation must occur safely inside the scaled vessel
continuously.
The sterilization vessel/chamber must be fitted with a motor driven shaft to which a heavy duty grinder (fragmenting
arm) is attached inside the vessel to produce an unrecognizable size of the waste product
The fragmenting are must rotate to agitated continuously throughout the heating and sterilization cycle to ensure
that the fragmented & agitated wastes (including sharps and liquids) are exposed evenly to sterilization temperature
and pressure.
Steam heat should be applied to the jacket only, while the agitated waste absorbs the heat from the jacket and makes
its own steam from its moisture content.
Should not need for special autoclave bags- simple bag or box should be workable
MUST not need for pre-treatment of the waste.
Liquids and gases MUST remain locked inside the vessel until sterilization is complete-nothing should be vacuumed or
pumped out in its infected state.
Jacket steam heat to dehydrate the waste completely regardless of its original water content.
All the hot condensate from the jacket is recycled, making the processor very economical to operate
All particles of the waste should achieve a high level of sterilization and not just “disinfection” due to the
continuous agitation.
Description of the Treatment Cycle of the processor
i)Loading
The waste has to be loaded by dropping bagged and or boxed waste into the open loading door on the vessel.
The loading door should be mounted at an angle on the top side of the vessel with suitably sized to accommodate the
infectious wastes for which it is intended
Over-loading or loading too tightly should not be an issue with this process, and hence no need of the special
operator skill.
ii)Heat –up and fragmentation
After loading , the vessel door is to be closed, and the outer jacket of the vessel is to be automatically filled
with high temperature steam, which should act as the main heating medium for heating the waste
During this heating cycle, the shaft and mixing arms should rotate continuously, causing the waste to be fragmented
and continuously tumbled against the hot vessel walls.
At this point, the waste is broken up into small fragments, and all material heats up rapidly, being evenly and
thoroughly exposed to the hot inner surfaces. The moisture content of the waste will turn in to steam, and the vessel
will start to pressurize.
Initially, no steam will be injected into the waste. If there not enough moisture in the waste to pressurize the
vessel, a small amount of steam is to be automatically added until the desired pressure is reached.
At the end of the period, the correct sterilization temperature and should be reached, and the sterilization period
should start.
iii)Sterilization period
The amount of steam fed to the outer jacket is to be regulated to maintain the desired temperature & pressure of the
inner vessel.
The mixing arms (grinder) MUST continue to rotate throughout this cycle to ensure even sterilization pressure and
temperature for all wastes.
The treatment time should be either 15 minutes at 132◦C OR 30 minutes at 121◦C to achieve level 6log10 sterilization
The intense subjugation of the waste to high temperature and pressure moisture in a dynamic environment should also
cause the waste to hydrolyze, that is a rapid decomposition of organic material.
iv)De-pressurization
After the treatment time , the steam to the jacket should remain on, and the internal vessel is to
be vented through a condenser, and de-pressurized. Thus, the waste loses its water content
through a combination of heat input from the jacket and flashing of water due to
depressurization.
v)De-hydration
Further dehydration is to be achieved by maintaining heat input and mixing-almost total dryness should be achieved.
