The purpose of this work is finding a solution to the brewery wastewater refining problem. As a result, a preliminary treatment for wastewater emission in the town sewage is given. For huge ecological recipients demands, a possibility of the complete refining is presented. After giving the analysis, conceptions for solutions to recycling plants are displayed. The contribution of this paper is in solving the problem of the treatment of the wastewater generated during technological process of beer production and is based on several years investigation.

The subject of the paper is eco-technological procedure of the treatment of the sludge generated during conventional purification (Cn(-) oxidation, Cr(6+) reduction, chemical precipitation of the other metals) of the wastewater from galvanic process. The detailed analysis of the waste sludge with the determination of high flow (the water eluate) and low flow (HNO3-eluate) fraction as Cu(2+), Cr(3+), Cd(2+), Ni(2+), Pb(2+), Zn(2+). The point of the paper is the treatment of the sludge as the dangerous waste into useful product glass-ceramics, with eliminating of the generation of the dangerous and harmful materials in environment. Experimental investigation has achieved the point and approved that with this procedure it is possible to transform chemical active matters (Cu(2+), Cr(3+), Cd(2+), Ni(2+), Pb(2+), Zn(2+)) using the phase and chemical transformation into very stable structure where the pollutants can not be activated even under critical conditions as high temperature, influence of acids and alkalines, etc.

The surface water quality preservation is dependent on the used technology of wastewater purification, waters that are thrown in natural streams and on the used methods for the purification efficiency evaluation. The field microbiological test (FMT) is made of a concentrated culture medium that allows the evidencing of enterobacteria below values of 100/cubic cm, therefore it was used for sanitary ranking of treated wastewaters at the sewage treatment plant of Timisoara (Romania). We noted a 100% correlation between FMT and the official coliform bacteria test.

Over the last several years, the investigations of the natural zeolites application in the sorption processes have been intensified. Purification of waste waters in order to remove lead, cadmium, copper and other heavy metals, is one significant example of such application. In this paper, the investigations results on characteristics of the natural and chemically activated zeolites from the region of Vranje (Serbia, Yugoslavia), are presented. The experiments with zeolites were performed after determination of their physico-chemical characteristics. Adsorptive characteristics were investigated under laboratory conditions, in a liquid medium, depending on granulation and concentration of the heavy metals. As the obtained results show, these natural materials can be used to remove heavy metals from the waste waters.

The work describes optimization on the process of separation of a synthetic dye, methyl orange, from water by sorption on iron(II) hydroxide, using response surface methodology. It was established that the optimum sorption conditions for dye removal on iron(II) hydroxide are: pH 9.1, iron(II) concentration 128 mg/l, dye concentration 10 mg/l, whereby the highest efficiency of dye removal is close to 90%.

Concept of anaerobic treatment process of food processing wastewater is discussed. In this scope there are: 1) formulation of anaerobic process, b) general process scheme defining, c) choice of process (digester type, single- and two-step mode, operating temperature), and d) define of process variables (hydraulic and organic load, removal efficiency, quantity and composition of biogas, etc.).

The work is concerned with the possibility of inactivation of galvanic sludge formed in treatment of wastewaters of electroplanting plants by imbedding the waste in a glass material. Glass can be synthesized in contact with the waste by mixing and heating with glass constituents. The efficiency of inactivation was monitored by leaching the obtained materials. The results of leaching tests showed that the highest amount of electroplanting sludge (about 30%) can be inactivated by vitrification of the following mixtures: 26.3% of electoplanting sludge, 43.7% of sand, and 30.0% of Na2CO3 at 1000 deg C; 30% of galvanic sludge, 49% of sand and 21% of Na2CO3 at 1100 deg C.