or the other of floats 44 and check valve 12 must be provided but both are not necessary conduit 46 is an overflow conduit and when the level of liquid 16 in chamber 15 is lower than outlet 45 conduit 46 would be empty the pump 36 would in such a case be fed from reservoir 32 when liquid 16 in chamber 15 is at a level high enough to feed conduit 46 the pump 36 is fed from the conduit 46 source in this manner a constant head of liquid 16 is maintained in chamber 15 with reference to the temperature control means of fig4 liquid 16 in the pelletizing tank 15 removes heat from the incoming molten sulphur 21 thereby increasing in temperature the hotter liquid in the top of the pelletizing tank 15 flows directly to the sump tank 32 via conduit 46 and then is pumped to both the pelletizing tank 15 and the heat removal unit 49 the amount of hot liquid entering the heat removal unit 49 is regulated by a control valve 50 which in turn is regulated by a temperature sensing device ti specifically as the pelletizing liquid 16 increases in temperature the sensor ti is adjusted to proportionately open the control valve 50 thereby allowing hot liquid to enter the heat removal unit 49 which lowers the temperature of the liquid and returns it to the sump tank 32 in the sump tank 32 the colder liquid from the heat removal unit 49 co mingles with the hot liquid from the pelletizer 15 thus producing a pelletizing liquid of the desired temperature with direct reference to the heat removal.