**1. Introduction**

Generally, a chain of surface treatment consists of sequences of functions (pretreatment, treatment, finishing), consisted of several posts (treatment bath, rinsing, passivation ...). The composition of industrial waste water of treatment surface contains a lot of heavy metals such Cu, Zn, Ni, Cr, Cd and the other toxic materials such as the alkalines, the acids and the cyanides. More and more it contains several complexing agents which influence the used process Na+ , OH<sup>−</sup>, SiO3 and Na2CO3, These products are generated in the operations of rinsing of materials before treatment. A variety of acids, HCl, H2SO4, HNO3, H3PO4, HCrO3, etc. is used to eliminate the oxidized films. The rejection of the stage of electroplating deposit contains widely metals and the following anions: BO3−, CO2<sup>−</sup> 3, Cr2O2<sup>−</sup> 7, F<sup>−</sup>, PO4 <sup>3</sup><sup>−</sup>, Cl<sup>−</sup>, NO<sup>−</sup><sup>3</sup> and SO4 <sup>2</sup><sup>−</sup>. Generally, wastewater contains many heavy metals. The most important of cations are Cr6+, it is reduced to Cr3+, while CN-is oxidized in the preliminary treatment.

Different treatment techniques for wastewater laden with heavy metals have been developed in recent years both to decrease the amount of wastewater produced and to improve the quality of the treated effluent. Although various treatments such as chemical precipitation, coagulation-flocculation, flotation, ion exchange and membrane filtration can be employed to remove heavy metals from contaminated wastewater, they have their inherent advantages and limitations in application [1].

Chemical precipitation is widely used for the treatment of electroplating wastewater [2, 3]. It consists of adding a base followed by sedimentation. The pH is adjusted to the minimum solubility, so it is difficult to treat multiple metals simultaneously. Coagulation-flocculation has also been employed for heavy metal removal from inorganic effluent [4]. Sorptive flotation has attracted interest in Greece and the USA [5–7] for the removal of non-surface active metal ions from contaminated wastewater. In recent years, ion exchange has also received considerable interest in Italy and Spain [8, 9] as one of the most promising methods to treat heavy metals. Starch xanthate (XA) synthetic polymers resins grafted cellulose natural zeolites are used. This process is particularly effective for the recovery of metals, but the cost of the process is very expensive and often justified only metals are recovered [10]. Due to its convenient operation, membrane separation has been increasingly used recently for the treatment of inorganic effluent. There are different types of membrane filtration such as ultrafiltration, nanofiltration and reverse osmosis. Membrane filtration has used in Taiwan and in South Korea [11, 12].

The adsorption treatment is widely used with activated carbons, this process has several advantages: it is very effective in removing heavy metals even at low pH [13] with different adsorbent materials such as polymers [14–16] and clays [17–19]. Electrolysis is generally used to treat water with high metal content. One of the major obstacles encountered in this technique is the complexity of the environments to be treated that leads to a series of redox reactions [20]. In recent year, the clean Technology constituted preventive actions to review and question the production concept, these actions converge to a common point: Targeting the pollution source rather than its reverse vector example osmosis [21] and zero discharge principle [22, 23].

In general, control of water flow requires the establishment of means for counting and control flow at the entrance of each channel. In addition, it reduces the consumption of reagents and production of sludge treatment plant, which is a significant gain in operating costs. Several techniques exist to recover the flow pollutants at the source to mention a few key principles:


**109**

*Characterization and Treatment of Real Wastewater from an Electroplating Company by Raw…*

The objective of this research was to study the ability of raw chitin to purify wastewater loaded with a mixture of heavy metals. This chapter first focused on the physicochemical characterization and the determination of heavy metals levels in wastewater followed by adsorption treatment. We started the study by the global rejection of the society then by the rinsing waters running at the exit of the electroplating baths. Finally, we have studied the comparison between the efficiency of the treatment of heavy metals by chitin shrimps - Ccre or chitin crab -Ccra thus analyz-

A study unit is MAFER located at CASABLANCA in MOROCCO. Its activity is surface treatment. The studied unit of surface treatment consists of five chains. Every chain is determined by the succession of tanks. The average capacity of baths varies between 950 and 1710 l. The majority of baths has a volume of 1440 l and is fed by well water except the bath of metallic deposit and the baths of rundown which are filled by the drinking water. Waters of the baths of the dead rinsing are recycled in the bath of metallic deposit. The water supply of well often matches 1 h a day. Whereas the drinkable water supply is made after

the shells of Shrimp (Ccre) and the shells of crabs (Ccra) are isolated at first by their mild part (protein) washed in bidistilled water then dried at 100°C during 48 h [17], then crushed and sieved. The size grading is understood between 100

A mass of the adsorbent is placed in contact with the rejection to be treated (100 ml). The suspensions were stirred (500 rev/min) in constant temperature (25 ± 2°C) until adsorption equilibrium obtained for a duration of 4 h [17]. The supernatant is filtered and the equilibrium concentration (Ceq) is determined after

PH: Measured using a pH meter ORION RESEARCH type and a combined glass

Chemical oxygen demand (DCO): Determined according to AFNOR T90-101. The principle consists in oxidizing the organic matter contained in wastewater by

Suspended solids (MES): Determined according to standard AFNOR T90-105,

Dissolved oxygen (OD): Determined using a pulse oximeter, the assay is performed directly by immersing the electrodes in water for analysis. The oxygen reduction at the cathode generates a proportional current to the partial pressure of

the filtering is done on Whatman paper (0.45 mm). The drying of the already

Electrical conductivity (CE): measured using a conductivity type ORION

mineralization by flame atomic absorption using a Philips type PU 900.

\*Physico-chemical analysis of the rejection quality:

weighed filter is done at 105°C for 1 h and weighed.

*DOI: http://dx.doi.org/10.5772/intechopen.89058*

**2. Materials and methods**

**2.1 Preparation of the adsorbent**

RESEARCH mod 101 and a 1 cm cell.

an excess of silver sulfate.

oxygen in the cell.

draining of bath.

and 125 μm.

electrode.

**2.2 Adsorption test**

ing the possibilities of in situ treatment and recycling.

*Characterization and Treatment of Real Wastewater from an Electroplating Company by Raw… DOI: http://dx.doi.org/10.5772/intechopen.89058*

The objective of this research was to study the ability of raw chitin to purify wastewater loaded with a mixture of heavy metals. This chapter first focused on the physicochemical characterization and the determination of heavy metals levels in wastewater followed by adsorption treatment. We started the study by the global rejection of the society then by the rinsing waters running at the exit of the electroplating baths. Finally, we have studied the comparison between the efficiency of the treatment of heavy metals by chitin shrimps - Ccre or chitin crab -Ccra thus analyzing the possibilities of in situ treatment and recycling.
