**5. Study flow of pollution**

*Recent Advancements in the Metallurgical Engineering and Electrodeposition*

**4.2 Rinsing water treatment test common to plating baths**

*Concentration of metal ions in the rinse of metal in mg/l of sample 3/10.*

metals does nothing, but increasing the removal of the Ni.

flushing streams they reach 98.08%.

The current water rinses are treated the same way that releases overall. We studied the case of Cu, Ni, Cr and Zn. For each metal we have tried to work on two different samples. The results of this study are summarized in the **Table 9**

Current rinse of Ni 15.05 0.59 1.93 0 Current rinse of Cr 3.87 188.6 0 12.42 Current rinse of Cu 0 1.17 0 68.3 Current rinse of Zn 0 0 670.11 4.73

**Ni Cr Zn Cu**

The expression of the calculation of the % of adsorption is 100 \* C0-Ceq/C0. Cu: The table shows that the removal efficiency increases as the mass of material increases especially for the rejection diluted. In general, treatment of rinse water is more effective than the treatment of Cu in the global rejection [6–8]. Indeed, the removal percentages do not exceed more than 63% in the global rejection while for

Ni: In the case of Ni, we see that the residual concentration decreased from 1.5 to 1.2 mg/l with a percentage reduction is very small compared to the percentage reductions in the case of total rejection [6], we can say that the presence of other

Cr: the removal yields is relatively low compared to those found in the overall rejection, it does not exceed 28% for the diluted rinsing and 25% for the concen-

Cu 2 C (mg/l) 0.59 0.54 0.31 0.12

Cr 2 C (mg/l) 15.39 15.43 16.15 15.10

Zn 2 C (mg/l) 0.290 0.051 0.039 0.033

Ni 1 C (mg/l) 1.2 — — —

*Changes in percentage of the adsorption of metal ions of the current rinses depending on the dose of added* 

**Weights of adsorbant (mg/l) 50 100 150 200**

% of adsorption 92.23 89.49 84.45 90.17

% of adsorption 71.64 74.06 84.98 94.39

% of adsorption 12.14 17.34 25.18 20.68

% of adsorption 27.3 27.11 23.71 28.67

% of adsorption 4.99 — 16.83 90.23

% of adsorption — — — —

% of adsorption 66.27 — — —

1 C (mg/l) 1.99 2.69 3.99 0.43

1 C (mg/l) 165.7 155.9 141.1 149.6

1 C (mg/l) 63.66 — 16.52 6.54

**118**

**Table 9.**

*material.*

below.

**Table 8.**

trated rinsing.

A chain consists of a set of tanks whose general functions are: surface preparation, processing and finishing of the piece part in question. Each tank is defined by three characteristics:


The unit of surface treatment under study is composed of five chains. Each channel is determined by the succession of tanks. The average capacity of baths varies between 950 l and 1710 l, but most of the bath has a volume of 1440 l, the majority of the baths is powered water wells except metal plating baths and degreasing baths, which are filled with drinking water, bathing water that is recycled in metal plating baths of rinses dead. Water supply wells are often for an hour a day, while drinking water is draining after a bath. Discharges baths is collected through pipes that lead to the aerated sewage. All discharges are evacuated in the rough, but the rejection of the flushing stream which is recycled zinc. We were interested in flushing power of Ni and Cr; we followed up daily flow rates of 7/9 to 3/10 in **Figures 7** and **8**.

We found that the high flow rates were recorded for Cr and Ni, the rate of flushing power of Cr can be up to 600 l/h and the neither flushing current reached a maximum of 841 l/h.

• The flow rates of Ni in the chain will fluctuate between 260 and 390 l/h, they will reach 389.21 l/h, a value which represents the 1/3 of the bath of treatment, that is to say that every day, the third of the rinsing bath is changed with a capacity of 1440 l. This during the fifth of the rinsing bath of Cr is changed. These waters are evacuated; this appears from the color of releases. Rejection of Cr is yellow while the rejection of Ni is green.

The Ni current rinsing flow varies from one channel to another varies from the average flow 389 l/h for channel II 738.8 l/h for the string I.

• The temporal variation of the flow does not follow a given order; it varies from day to day depending on water supplies that are directly related to the availability of water in the well. - We tried to compare these rates with those of other baths as bath chemical degreasing and pickling bath. The flow of degreasing bath is lower and messy, while the stripping is relatively constant and is around 400 l/h.

**Figure 7.** *Monitoring rinsing flow flows as a function of time.*

#### **Figure 8.**

*Average flow rates of rinses for different metals.*

From this study, it follows that the rates baths variation is random. This makes the adaptation of a method for processing or recycling of waste water very difficult. In conclusion, we must control the flow based on the minimum and maximum values recorded by installing a storage buffer.
