Neutralization systems

AW neutralization technique, the modern and economic solution for the neutralization of waste waters from laboratories or industry. Essentially, three methods are used:
- Batch neutralization
- Continuous feed neutralization
- Reactor neutralization

Batch neutralization system

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With this method waste water is piped into a tank where the content is mixed intensively by an agitating mixer once a certain level has been reached and acid or an alkaline solution is added by a dosing unit, if necessary. On reaching the requested pH-value and following a certain settling period, the content is drained into the sewer. No further waste water may be piped into the tanks during the neutralization process, so that in most of the cases two neutralization tanks are required which are operated alternately.
Advantages:          Acid and alkaline waster waters are mutually
                       neutralized by the buffer action, so that less acid or
                       alkaline solution is required.
Disadvantages:       Great expenditure for major installation, thus only useful
                       for smaller throughputs.

Continuous feed neutralization system

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Only one reaction tank is required here which can be fed continuously. The pH-value is measured constantly and either acid or an alkaline solution is added by a dosing unit according to the deviation. The tank is always full, i. e. when 1 liter flows in at the front, 1 liter is drained off into the sewer at the back. If your waste waters have different pH-values and enter the system with a time lag, these cannot be mutually neutralized leading thus to a high consumption of chemicals.
On the grounds of the hydraulic circumstances, the waste water passes at different speeds through the system. The resulting different periods of direct contact may lead to an underdose or overdose.
This method should be used in particular, where waste water has a nearly constant pH-value.
Advantage:        Low expenditure for small installation compared with batch neutralization
Disadvantage:    High consumption of chemicals

Reactor neutralization system

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The AW reactor neutralization system combines the advantages of batch neutralization and continuous feed neutralization.
The waste water to be treated is at first piped into a buffer tank. At a certain level the water is delivered into the reactor by means of a pump. The pH-value is measured in front of the reactor and either acid or an alkaline solution is added by a dosing unit according to the deviation and mixed intensively in the reactor.
The measured pH-value at the reactor outlet now determines whether the waste water can be transferred to the sewer via the pH final check or whether the water is pumped back into circulation into the buffer tank.
A certain lead time ensures that the content of the buffer tank is mixed intensively in the first place at the start of the neutralization prior to the dosing of acid or an alkaline solution.
Thus it is ensured that waste waters with different pH-values can be mutually neutralized saving thus chemicals.
Advantages:       Reduced consumption of chemicals and thus
                         less operating expenses.
                          Reduced expenditure for small installation saving
                          thus investment costs.
                          Less floor space required saving thus
                          building costs.