Temperature and Moisture

Important matter is the temperature of the pellets. In a case pellets are kept in a   tight, badly ventilated   storage   an   auto combustion of the pellets may occur. Temperature rise over 50-55 degr  C has to be regarded as critical, such pellets should not be loaded on  a   vessel.

There are three ways of temperature measurements:IR gun (only spot measurement of the surface), temperature   lance (up to 2 m length to measure also deeper in the pile, but only spot measurement),   IR thermo camera (taking a thermo picture of the surface). All methods are only indicative. When   monitoring   temperatures during loading operation, Control organizations   are always giving only range of temperatures.

  

When at loading  temperatures show up to be  close to the critical level  of 50 – 55°C or above, extra attention to it is given  and  loading may even be stopped.  If   “hot spots”   in the cargo are observed  loading is stopped  immediately. Hot spots may create an  auto combustion of the cargo during the sea voyage.

Very important   seems to be cooling down   the pellets before loading on the vessel. If the pellets are coming directly from the production and are immediately loaded on a vessel their   temperature may be quite high and    that  may  create  ignition  of the pellets . Same situation may arise when loading hot pellets into the silos in the port. 

Wet spots in the  wood pellets cargo have to be also treated with very big caution. High moisture content is triggering in wood pellets an exothermic reaction which may course a fire during the sea voyage. “Wet spots” with high temperature  are sometimes noticed in the river barges transporting wood pellets to big sea  ports  for loading a huge vessel. Sometimes there could be about 20-25  barges waiting  in the  port for loading of a 30.000-40.000 mt  Handy size vessel. Due to condensation under the cover of the barge water may come into the cargo and create a “wet spot”. At the arrival of the barges all  covers have to be opened, their cargo to be carefully  checked   and  “wet   spots” , if any , to be  removed  to avoid  getting of the wet pellets  into the holds of the big vessel.