The technology of the pressurized steam dryer in beet sugar factories
It has always required a lot more of energy to remove 1 ton of water from beet pulp than from thin juice.
This is no longer true.
Imagine if the diagram shown below was reality
This is still a dream. Beet pulp is not a fluid, and the heat transfer
coefficient of beet pulp is not the same as for thin juice.
Nevertheless, the dream is not out of reach, even though some problems has to be solved.
The pulp can be fluidised in a fluid bed, and transfer of energy to the pulp can be done by super heated steam.
By this the following diagram becomes a possibility.
Energy is supplied as steam at a pressure of e.g. 16 bar.
The feed steam is returned as a pure condensate and used as feed water in the boiler.
All the energy supplied to the dryer is leaving as steam,
and used as energy suppy for the first step of the evaporator.
The steam leaving the dryer is actually the water evaporated from the beet pulp.
By using this steam in the first step of the evaporator, a full energy recovery is achieved,
and air pollution from dust and smell is fully avoided.
The energy returned from the steam dryer is about half of the energy needed
in the first step of the juice evaporation.
Evaporator 1 is split into 2 parallel bodies 1A and 1B in order to separate the condensate.