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.

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.).

Sludge from a wastewater treatment plant can be applied to soil to make use of its fertilizing properties, neverthelessit is necessary to study all the effects of this deposition to ascertain any possible hazardous properties. Interactions among the soil, the water, and a lime-stabilized waste watersludge were studied, both in batch experiments, and in columnpercolation experiments. Firstly a physico-chemical characterization of the soil and the sludge used for the experiments was carried out. This analysis included pH, organic matter, cation exchange capacity, metals and cations.The kinetics and equilibrium of the sludge-water and leachate-soil systems were studied in batch experiments; thekinetics were fitted to a first order differential equation and distribution coefficients were found for the equilibrium.Experiments in columns (10 cm diameter × 50 cm height) were carried out with a bed of sludge over a bed of soil usingdifferent sludge/soil ratios and then 6 L of water (rainfall)was poured over the beds. Results showed good adsorption of Ca and a complete leaching of the aqueous phase of this ion afterpassing a volume of water equivalent to three volumes of the column. The concentration of heavy metals (Zn, Ni, Hg, Cd, Pb and Cr) in the leachates did not reach the admissible legal limits (Spanish and European regulations) in any case.

A fish canning facility processes 1900–2000 tons of mackerel and sardine annually at arate of 10–15 tons per day for a total of 200 days yr⁻¹. This factory generates an average of 20 m³ of industrial wastewaters per day. The objective of our study, which was carried out on a bimonthly basisfrom December 1995 to November 1996, was to determine the overall pollutant load associated with this effluent in relation to the applicable Egyptian Standards and to propose methods for pollutant load reduction before discharging it to the local sewer. The methods were to benefit through the recovery of wasted organic load and transform it into an environmentally safe residue amenable for either immediate reuse or final disposal thereafter. Five chemical coagulation/flocculation treatments were tried using ferric chloride, alum, lime, ferric chloride and lime, and alum and lime. The best method involved the use of FeCl₃ and Ca(OH)₂ (0.4 g Fe L⁻¹ and 0.2 g Ca L⁻¹, respectively) which reduced the average influent BOD₅ from 989 to 204 mg L⁻¹, the COD from 1324 to 320 mg L⁻¹, TSS from 4485 to 206 mg L⁻¹, total protein content from 812 to 66 mg L⁻¹ and oil and grease from 320 to 66 mg L⁻¹. The separated dried precipitate averaged 50 g L⁻¹ which was found to contain 40% by weight recovered protein and 20% recovered fat. The solid was ideal for on-site reprocessing as animal feed. As well, the final effluent, if not discharged to the area sewer, was safe for controlled use in some irrigation applications or forestry projects at the desert area surrounding the factory.

Although confined animal production generates enormous per-unit-area quantities of waste, wastewater from dairy and swine operations has been successfully treated in constructed wetlands. However, solids removal prior to wetland treatment is essential for long-term functionality. Plants are an integral part of wetlands; cattails and bulrushes are commonly used in constructed wetlands for nutrient uptake, surface area, and oxygen transport to sediment. Improved oxidation and nitrification may also be obtained by the use of the open water of marsh-pond-marsh designed wetlands. Wetlands normally have sufficient denitrifying population to produce enzymes, carbon to provide microbial energy, and anaerobic conditions to promote denitrification. However, the anaerobic conditions of wetland sediments limit the rate of nitrification. Thus, denitrification of animal wastewaters in wetlands is generally nitrate-limited. Wetlands are also helpful in reducing pathogen microorganisms. On the other hand, phosphorus removal is somewhat limited by the anaerobic conditions of wetlands. Therefore, when very high mass removals of nitrogen and phosphorus are required, pre- or in-wetland procedures that promote oxidation are needed to increase treatment efficiency. Such procedures offer potential for enhanced constructed wetland treatment of animal wastewater.

Most livestock wastewaters treated in constructed wetlands are typically rich in ammonium N. The objective of this study was to evaluate the soil-water ammonium distribution and the diffusive flux through the soil-water interface. Wetland system 1 (WS1) was planted to rush and bulrushes, and wetland system 2 (WS2) was planted to bur-reed and cattails. Nitrogen was applied at a rate of 2.5 g m-2 d-1. Interstitial soil water was sampled at 9, 24, 50, and 70 m from the inlet. In both wetlands, we found that NH4+ diffusion gradient and N losses were highest in the wetland system with lowest water depth. From other studies, we knew that shallower depths may have promoted a more effective interfacing of nitrifying and denitrifying environments. In turn, this N reduction in the water column may be the reason for steady NH4+-N upward diffusion fluxes. The assumed mechanism for N removal has been nitrification and denitrification but ammonia volatilization could also have occurred. Although diffusion may explain a significant portion of the material transport between the soil-water interface, the large differences in concentrations between outlet and inlet need further explanation.

Swine waste is commonly treated in the USA by flushing into an anaerobic lagoon and subsequently applying to land. This natural system type of application has been part of agricultural practice for many years. However, it is currently under scrutiny by regulators. An alternate natural system technology to treat swine wastewater may be constructed wetland. For this study we used four wetland cells (11 m width 40 m length) with a marsh-pond-marsh design. The marsh sections were planted to cattail (Typha latifolia, L.) and bulrushes (Scirpus americanus). Two cells were loaded with 16 kg N ha-1 day-1 with a detention of 21 days. They removed 51% of the added N. Two additional cells were loaded with 32 kg ha-1 day-1 with 10.5 days detention. These cells removed only 37% of the added N. However, treatment operations included cold months in which treatment was much less efficient. Removal of N was moderately correlated with the temperature. During the warmer periods removal efficiencies were more consistent with the high removal rates reported for continuous marsh systems - often > than 70%. Phosphorus removal ranged from 30 to 45%. Aquatic macrophytes (plants and floating) assimilated about 320 and 35 kg ha-1, respectively of N and P.