A heating process takes place in a batch heater (Fig. 6.18) with the following constructive and technological characteristics: T ∘ i = T ∘ ext = 20 ∘ C, T ∘ agi = 90 ∘ C, M h = 60 kg, M w = 50 kg, M...

A heating process takes place in a batch heater (Fig. 6.18) with the following constructive and technological characteristics: T^∘
_i
= T^∘
_ext
= 20
^∘C, T^∘
_agi
= 90
^∘C, M_h
= 60 kg, M_w
= 50 kg, M_ag
= 20 kg, A_T
= A_Text
= 0.4 m², A_TTr
= 0.01 m², K_Ti
= K_TTr
= 1500 kcal/m²hK, K_TTag
= 800 kcal/m²hK, KText = 200 kcal/m2hK. Specific heat values for the heated material and heating agent are c_ph
= c_pag
= 1 kcal/kgK, and for all metallic parts of the heater, thermo well included, cpw = 0.15 kcal/kgK. The heating agent flow varies between 0.08 m³/h and 0.8 m³/h.

The heater has an anchor for homogenization with a mass M_a
= 12 kg. The temperature inside the heater is measured with a thermo resistor protected in a thermo well with a mass M_Tr
= 0.5 kg. The heating agent is hot water. The controllability of

the process has to be determined and a proposal for an adequate control system is required.