General Description
A cleaning system has been
designed as a central unit for the automatic cleaning of production plants in
the foodstuff sector.
Important characteristics for the design of such
a system are:
- Economical use of water, caustic solution and energy by recycling the
rinsing water, hot water and caustic solution and thereby reduction of waste
water quantity and charge at the same time.
- Automatic increase in concentration of the caustic solution as well as
automatic heating of caustic solution and water
- Automatic control of the cleaning process
- Variable programs, easy to change by the operator, protected via password
The preselected system parts will be cleaned continuously via a central
cleaning unit. As far as possible the used cleaning agents and water are
recycled and used again for the following cleaning run. According to the
requirements 1 - 4 cleaning cycles can be provided for and thus 1 - 4 objects
can be simultaneously cleaned independent of each other.
Programs
A cleaning program can be composed of
the following steps:
- Pre-rinsing with water that has been already used for a preceding
cleaning process. The returning pre-rinsing water is eliminated.
- Caustic treatment, hot. The caustic solution is
redelivered into the caustic tank controlled via a conductivity meter in the
return pipe.
- Hot water. By means of a heater the water is heated up to a preset
temperature. Controlled via a conductivity meter and the temperature metering,
the water is returned into the hot water tank.
- Disinfection. In a fixed ratio disinfectant is added to the fresh
water.
- Rinsing, cold. This step is always the last in a cleaning
operation. After passing through, the water is collected in the pre-rinsing
tank.
The controller unit renders it possible for the operator to combine, to
optimize and to store different runs for each object by himself, in order to be
able to use these later on. As a rule, the following programs in question are:
- Rinsing rinsing only
- Cold-CIP pre-rinsing and rinsing
- Hot-CIP pre-rinsing , hot water and rinsing
- Full-CIP pre-rinsing, caustic solution, hot water and
rinsing
- Disinfection can be selected additionally in the programs
2) - 4)
Controls and Functions:
- The flow in the return pipe is monitored for recognizing system errors.
- The temperature in the return pipe is monitored during the caustic and hot
water phase.
- Flow control in the prerun for adapting the flow to the CIP object at an
optimum.
- The times for the program steps are variably settable.
- On tank cleaning the prerun is controlled by pulses, if required.
- The dosing of the disinfectant is done proportionally to the water flow.
- The cleaning tanks are always automatically re-filled if the level has
fallen below a certain limit value.
- The increase in concentration of the caustic solution and the heating of
the cleaning agents is effected automatically.
- The cleaning cycles work independently of each other.
System Scheme
The enclosed scheme shows a system
with 2 cycles which can be operated independently of each other, i.e. caustic
solution e.g. is running in cycle 1, whilst in cycle 2 disinfection is run. The
preruns are equipped with mix-proof valves so that a mixture of e.g. rinsing
water with caustic solution is avoided. The return to the hot water tank is
also protected by mix-proof valves.
Besides the complete, fully
automatic system described above, GEA also offers systems with modified
configurations, e.g.:
- Without pre-rinsing tank (rinsing water is used for pre-rinsing)
- Without hot water tank (the water temperature is reached within
circulation)
- Without rinsing tank, if the water pressure is relatively constant and can
supply permanently sufficient quantity
- Semi-automatic function instead of full automation
- No mix-proof valves
- With buffer tanks for caustic concentrate and disinfectant, if the supply
is not done from a chemical store