EURO-ECO 2010 Hanover 2 - 3 Dezember 2010	Environmental, Engineering - Economic and Legal Aspects for Sustainable Living
	European Academy of Natural Sciences, Hanover European Scientific Society, Hanover University of Bremen, Bremen

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Abstracts EURO-ECO 2010

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The manufacturing of dairy products usually pollutes the environment because water and air are used in the processing of raw mild materials. Dairy enterprises degrade the ecological situation in spite of the fact that they do not directly produce or use toxic substances.

Russian standards for water consumption and water allotment allow four to five tons of wa-ter per one ton of the raw feed stock, depending upon the kind of production. Water supplied for technological needs must meet the requirements for drinkable water. Moreover, 75-80% of water which is not part of the finished product should be discharged into the environment. In the case of dairy products manufacturing, the most polluted part of the waste water is formed during washing of technological equipment. This water contains the remains of the raw dairy material and the proc-essing of intermediate and finished products; thus it is an aqueous colloidal system of high-molecular organic compounds.

High values of chemical and biological consumption of oxygen (CCO and BCO) can be predicted for the oxidation of the organic components in milk because lipids, proteins, carbohy-drates, and organic acids have a complex chemical structure. The values of these parameters for dif-ferent kinds of raw dairy / foodstuff are presented in Table 1.

Product	Dry substances	Fat	Protein	Lactose	CEO	BCO
	“%	%	%	%	10-3 g/kg	10-3 g/kg
Whole milk	11.5-12.5	3.0-4.0	3.0-4.0	4.8	192.9-218.6	135.5-156.2
Non-fat milk	8.3-8.5	0.02-0.06	3.0-4.0	4.7-4.9	112.0-119.3	72.4-69.1
Buttermilk*	7.7-8.0	0.4-0.9	2.8-3.0	4.0-4.5	104.5-111.9	72.4-75.1
Whey	6.0-6.2	0.1-0.2	1.0	4.5-4.7	72.0-77.0	51.7-55.9
Cream	40.4-43.0	33.0-35.0	2.0	3.0	871.0-936.5	695.0-747.0

There are different systems designed for separating butterfat from the sewage water; the ob-tained product can be used only for technical purposes. The non-fat water-milk mixture is a protein-carbohydrate colloidal system with an extremely high value of BCO.

Soil fertilizers are produced under aerobic and anaerobic fermentation of organic substances from the rinse water but this does not seem a rational solution of the problem.

Fine cleaning of water can by obtained by electrofloat coagulation in a combination with re-agent coagulation. The fat and protein sediment formed in these processes is used for fodder and technical purposes. The extent of fat extraction is 93% with a reduction of CCO of 80%. Non-reagent electrochemical coagulation in a discharge allows up to 86.8% extraction of protein and 85% extraction of fat.

The filtrate, the solution passed through the semipermeable membrane, is a limpid colorless liquid with a mass% content of 0.0023 lipids; 0.06 protein; and 0.50 lactose. Concentration of the proteins and lipids in the filtrate indicates a high efficiency of ultrafiltration. CCO is reduced by 90-95%. Relatively high values of CCO for the filtrate, 700800 mg/kg, are due to the presence of lactose that is not detained by the ultra-filtration membrane. During subsequent processing of the ultra-filtrate by reverse osmosis, the CCO of water is reduced up to 2-6 mg / kg while the standard for drinkable water is 15 mg/ kg. Ultra-filtrate cleaned by reverse osmosis method is fed into a closed water rotation of the process. Concentrate containing 4-5 mass% lactose is processed by known lactose-obtaining technology. The combination of reverse osmosis and ultra-filtration pro-vides an efficient and highly-productive processing of water-milky systems. In the experiments it was established that the reverse-osmosis treatment without preliminary ultra-filtration results in the rapid contamination of membranes and a decrease in the rate of filtration.