The operating parameters are as follows:-

• Maximum reactor walls temperature -500 degree C.

• Desired maximum surface temperature on insulation surface -50 degree C.

• Estimated surface area to be insulated – 120 met.sq.

• From the chart at 1000 deg f(  heat loss for 100 mm thick , 160 m.sq density  rock wool  mat). = 2.7126 btu/hr./sq.ft.   =  238 kcals/hr.sq.m

• Therefore total heat loss /hr through  insulation  – 120  x 238 =28,500 kcals/hr.