Performance Evaluation of a Kenaf Decorticator

Abstract

The  performance  evaluation  of  an  existing  kenaf  decorticator  was  carried out  in  this  study. A  field  was  planted  with  kenaf  at  the  Teaching  and  Research  Farm  (T&RF) of  the  Obafemi  Awolowo  University,  Ile  Ife.  The  field  was  maintained  and monitored  until  the  kenaf  was  10  weeks  old  when  the  evaluation  of  the machine  commenced.  The  kenaf  decorticator  was  evaluated  using  different operation  parameters,  which  include  plant  age  (10,  11  and  12  weeks  after planting),  kenaf  stem  size  (small,  medium  and  large)  and  decorticator speeds  (520,  600  and  680  rpm)  giving  rise  to   a  3  by  3  factorial experiment.  The  result  showed  that  the  highest  mean  of  throughput  value generated  was  614.70  kg/h  when  the  machine  was  operated  at  600  rpm  using large  kenaf  size  harvested  at  12  weeks  after  planting.  The  percentage  of kenaf  fibre  trapped  in  the  machine  decreased  from  24  to  13%  as  the  speed decreased  from  600  to  520  rpm  and  percentage  waste  collected  decreased from  54  to  32.  The  percentage  of  fibre  decorticated  also  increased  from 31  to  49%  as  the  speed  decreased  to  520  rpm..  The  kenaf  extraction efficiency  increased  from  74  to  91%  as  the  speed  deceased  to  520  rpm, kenaf  size  was  large  and  at  12  weeks  after  planting.  The  study  concluded that  the  optimal  operational  parameters  of  the  machine  were  520  rpm  with large kenaf size and 12 week of kenaf maturity.