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International Research Journal of Engineering and Technology (IRJET)       e-ISSN: 2395-0056
                        Volume: 07 Issue: 06 | June 2020                 www.irjet.net                                                                     p-ISSN: 2395-0072

        Autoclaves  are  closed  chambers  that  apply  heat  and   the microwave treatment and to reduce the volume of the
        sometimes  pressure  and  steam,  over  a  period  of  time  to   end  waste  for  disposal.  If  the  waste  is  dry,  water  is
        sterilize medical equipment. Autoclaves have been used for a   introduced  and  the  wet  waste  is  introduced  to  the
        century to sterilize medical instruments for re-use. Surgical   microwave  chamber.  Microwave  disinfection  works  only
        knives and clamps, for instance, are put in autoclaves for   when  there  is  water  in  the  waste  because  the  radiation
        sterilization.  For  medical  waste  that  will  be  disposed  of,   directly works on the water, not the solid components of the
        autoclaves can be used as heat treatment processing units to   waste.
        destroy  microorganisms  before  disposal  in  a  traditional
        landfill or further treatment. Autoclaves are a batch process,   Irradiation  is  another  method  which  disinfects  waste  by
        not a continuous one.  One problem with autoclaves is that   exposing  it  to  gamma  rays  that  are  fatal  to  bacteria.  A
        the process can aerosolize chemicals present in the waste,   radioactive isotope of cobalt is employed. This is basically
        leading to the potential for release of materials you would   the same radiation source used for radiation treatment of
        prefer  to  not  release.  This  can  pose  a  hazard  to  human   cancer. Irradiation does not change the appearance of the
        operators and to some extent the environment.          waste. So process designers often install mechanical grinding
                                                               or shredding upstream.
        Mechanical  treatment  in  waste  management  includes
        granulate, pulverizes, shreds, grinds, mixes, agitation, and   Although it is rarely used, vitrification can be an effective
        crushing. This can reduce the bulk volume of the waste by 60   treatment for medical waste. The solid waste is mixed in
        percent  or  more.  Waste  can  be  moved  through  the   when  glass  is  formed  (vitrification  means  production  of
        processing facility with augers, conveyor belts, and other   glass).  The  high  temperatures  kill  pathogens  and  some
        material handling systems. Mechanical treatment does not   combustible material may burn or pyrolyze, resulting in an
        kill  pathogens  or  disinfect  equipment,  but  it  can  reduce   off-gas. Remaining material is encapsulated in glass, which
        waste  volume  in  preparation  of  further  treatment  or   has a very low diffusivity. There is little danger of hazardous
        disposal.  Equipment  involved  can  include  crushers  and   materials leaching out of glass in significant quantities. The
        milling machines, Mechanical shattering or splintering  of   vitrified  waste  can  therefore  be  put  in  a  landfill  with
        waste can also alter its appearance, which can be useful in   confidence. [2]
        lessening the psychological impact of the waste on human
        observers.                                             2. Demand for appropriate technology for medical
                                                               waste disposal
        In  addition  to  being  able  to  reduce  bulk  waste  volume,
        mechanical systems can increase the surface area of the solid   The  demand  for  an  appropriate  technology  for  medical
        pieces  before  subsequent  chemical  or  heat  treatment.   waste  disposal  arises  from  the  fact  of  increasing  COVID
        Mechanical systems can also be an operational headache -   patients in the country. The major constraints to be taken
        more  things  to  go  wrong  and  more  things  to  be   are the social distancing efforts to control the COVID spread,
        decontaminated.  Further,  mashing  or  shredding  of  solid   difficulty  in  segregating  the  waste,  the  huge  quantity  of
        waste can generate dust. If this dust becomes airborne, it can   waste being generated each day and the infrastructure and
        be  a  workplace  hazard  and  a  threat  to  the  environment.   human  resource  scarcity  in  the  COVID  period.  The
        That’s why mechanical equipment is often kept in a closed   technology  for  medical  waste  management  should
        room or under a hood, at slightly lower than ambient air   invariantly address these constraints.
        pressure.
                                                               2.1  Controlled  pyrolysis  for  medical  waste
        Chemical disinfection, primarily through the use of chlorine   management
        compounds, kills microorganisms in medical waste and can
        often  oxidize  hazardous  chemical  constituents.  Chlorine   Newer technology plasma pyrolysis process fulfils all the
        bleach has been used for disinfecting processes for years   technical requirements to treat hazardous waste safely. It is
        Ethylene  oxide  treatment  is  used  more  often  to  sterilize   easy to maintain the arc in an oxygen-free environment, or
        equipment that will be reused. It is too expensive to use on   one can vary the plasmagen gas to alter the chemistry of the
        equipment or waste that will be sent to a landfill. EtO gas   process. The plasma pyrolysis system can have instant start
        infiltrates packages as well as products themselves to kill   and shut down. It is possible to add features like interlocks
        microorganisms that are left during production or packaging   and  automation  that  make  the  system  user-friendly.  The
        processes.                                             plasma  pyrolysis  technology  overcomes  almost  all  the
                                                               drawbacks of the existing waste-disposal technologies. But
        Microwave radiation is used to treat wastewater sludge and   Plasma is the state of matter obtained by breaking down
        as  a  heat  source  to  treat  medical  waste.  Microwave   atoms into ions and electrons by the process of ionization.
        treatment units can be either on-site installations or mobile   Plasmas  can  quite  easily  reach  temperatures  of  10,000
        treatment vehicles. The processing usually includes front-  degree Celsius. In plasma pyrolysis, generation of heat is
        end shredding of the waste, both to increase the efficacy of   independent of chemistry of material used. It is fast heating –


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