Foreword.
"DEMITEC" demineralizer units are capable of
removing partially or totally the salts dissolved in water. The treatment, commonly
referred to as "demineralization", is based on the ability of ion-exchange
resins to replace positive ions and negative ions present in the water, (H2O). The ion-exchange resins,
once their exchange ability has been exhausted, are regenerated using a solution of acid
(positive ion resins) and sodium carbonate (negative). Through the regenerating process,
the resins regain their exchange ability and the demineralization is ready to be started
again.
The standard "DEMITEC" demineralizers can, in practice, be divided into two main
ranges: the "CA" models, composed of two separate exchange resin columns (strong
positive ion column and strong negative ion column) suitable for obtaining average levels
of purity (conductivity in the range of 5 - 20 microS/cm) and the LM models.
The latter are characterized by a single column equipped with a mixed-bed exchange resin,
and are recommended for obtaining higher levels of purity. Installed after the
"CA" models, they enable the "CA/LM" line to be created, which is
particularly suitable where the use of the water is more sophisticated.
Choosing a demineralizer
When choosing a demineralizer, the basic criterion consists
in calculating the "cyclic production", i.e. the quantity of water to be treated
with a certain total salinity (in mg/l of CaCO3) between one regeneration and the next.
However, the complexity of the parameters to be considered - both chemical (% Na, SiO2, etc.) and technical (cost of
its operation, composition of the discharges, type of user) - makes it more advisable to
entrust this delicate task to Tecnomil experts, who will be able to advise the customer as
to the best choice for each individual case.
Main applications.
The use of demineralized water proves of fundamental
importance in any production activity which involves steam production or, in any event,
wherever it is necessary to minimize any effects the water might have on the product or on
the production structures.
The range of applications is extremely wide and, in practice, concerns all industrial
applications (foodstuffs and drinks, galvanic applications, electronics, chemical and
pharmaceutical applications, plastic materials, textiles, electrophoresis, heating plants,
etc.).
Operating features:
| -Min./max. operating pressure: | 2.5/5 bar |
| -Min./max. operating temperature: | 5/30 ºC |
| -Compressed air (provided by customer): | 5/7 bar |
| -Supply voltage/frequency: | 220V / 50Hz |
| -Maximum pressure drop when in operation: | 10 mt. water |
| -Regeneration control mode: | Push-button or conductivity meter signal |
Structural features:
TANKS: |
made from glass-fibre reinforced plastic for
CA models 15/30/40/50/100/150; made from carbon steel with hard rubber lining (4mm thick)
for larger models and the LM range. The tanks are protected on the outside by polyurethane-based paint applied after a sandblasting pretreatment and a coat of primer. The tanks are fitted with a nozzle-carrier plate and hatches. |
Piping: |
made of PVC, PN 10 |
Valves: |
up to model CA 60, multifunction valves with auxiliary valve are supplied; in higher models and the LM range, pneumatic diaphragm-type valves in PVC, PN 10. |
Regenerating agents: |
the regenerating agents are supplied directly from the storage tanks by means of an ejector |
Note. The following items are not included in the supply:
- storage tank of regenerating agents (HCI 33% Na OH 30 %).
- the acid and sodium carbonate flow-meters in the CA models 15/25/35/60.
- the system for the neutralization of the resin regeneration effluents.
