The physico-chemical wastewater treatments plant allow the removal of
polluants, usually poorly biodegradable, present in the water, through
the addition of chemicals. These additives, commonly called "reagents",
in some pH conditions, react with the pollutants, making them insoluble
and favoring their abatement by coagulation, precipitation and or
neutralization.
STA designs, build and offers a big choice of technologies and
solutions, the aim is providing the optimal solutions from a technical
and operational point of view, ensuring the achievement of purification
results at the lowest cost. The project and design of the treatment
steps of a chemical-physical plant and the suited technology to
particular needs is chosen according to the chemical-physical
characteristics of the wastewater, as well as the choice of the chemical
reagents, their dosages and the reaction times are the most important
parameter in order to obtain an efficient chemical purification system.
A chemical-physical plant can generally be divided into the following
treatment stages:
- Insolubilization of metal salts in basic solution;
- Flocculation;
- Coagulation;
- Sedimentation / decantation;
- Neutralization;
- Final filtration of purified water;
- Dehydration and sludge disposal.
In the first step the goal is to increase pH to a defined value, to make
insoluble salts of metal earlier present in dissolved form, turning into
metal hydrates.The following dosage of specific reagents allowes the
flocculation of suspended particles with the substance and the formation
of flakes.In order to obtain a better settle we add to the effluent a
polyelectrolyte that determin the coagulation of the flakes.
In the final separation section the aim is the water clarification and
sludge separation, that settles on the bottom of the decanter. The
clarified water are sent to a neutralization tank and then to the final
treatment as the physical filtration process on quartz / activated
carbon.
The sludge are collected from the bottom of the decanter, dehydrated and
finally disposed.
The reactions take place sequentially in distinct tanks dimensioned to
ensure the right contact times, or in a sequencing reactor with
intermittent cycle, a "batch", that incorporates the different steps of
treatment in a single basin.
The service of the company is always ready to intervene to guarantee
safety, competence and efficacy. STA offers varied and customized
formulas with one fundamental objective: provide to the customer a
package that combines maximum reliability with lower operating costs,
the rapidity of speech with the accuracy of performance, the user will
be free by the tasks and issues that it is more appropriate to entrust
to specialists.