Highly polluted wastewater accumulates in milk collection stations. Its biochemical oxygen demand (BOD5) ranges from 369 to 1388 mg O2 lE-1. The average contamination was 600 mg O2 lE-1. There was a comparatively small amount of biogenic materials in it: total nitrogen – 27.3, total phosphorus – 5.0 mg lE-1. When variations of wastewater amounts are high, sand filters of vertical filtration are successfully used for the treatment of household wastewater. Model investigations were carried out to establish the possibilities of using these filters in treating wastewater in milk collection stations. The efficiency of wastewater treatment with these filters was 99.3% by BOD5, 99.1% – by suspended solids, 91.2% – by total nitrogen and 98.8% – by total phosphorus. According to the research results dependency equations were made; they were used to calculate the amount of main contaminants in milk collection stations that infiltrated through a layer of silt of diff rent thickness. The calculations showed that wastewater treatment to permissible limits is ensured by filtration through 0.6 m thick layer of sand. The average treatment level by BOD5 in such a filter of vertical filtration would be 20 mg O2 lE-1 and the treatment efficiency – 95.9%. Treatment efficiency of total nitrogen would be 88.1%, total phosphorus – 96.9, suspended solids – 95.5%. Preliminary research in the model showed that sand filters of vertical filtration can be used to treat wastewater from milk collection stations.

The quality and nutritional value of milk and dairy products are considerably influenced by the stability of its constituents. The aim of the present study was to evaluate the possibility of enhancing oxidative stability of cow’s milk fat and vitamin B2 using carrots and palm oil feed supplement CAF 100 as sources of natural antioxidants in cow feed. Milk samples were collected after 25-day period of feed supplementation. The intensity of riboflavin losses during its photo oxidative degradation in sunlight was measured by the fluorometric method. A slight and significant (p is less than 0.05) difference in higher vitamin B2 stability was seen in carrot-supplemented group (TG1) milk, where the losses of vitamin B2 were by 3.01% less compared to CG (CG). The oxidative stability of butter oil samples stored in 60 °C temperature was analyzed by peroxide value (PV) method. The oxidative stability of samples initially affected by light from both trial groups was significantly (p is less than 0.05) higher compared to CG showing the good potential of the cow diet enrichment with carotenoid additives. The longest induction period (larger than 14 days) was observed in CAF-100- supplemented (TG2) cow milk fats, which can be explained by carotenoids and tocopherol presence and its possible synergism in fat protection. The induction periods of the TG1 and CG were 12.03 and 10.97 days, respectively.

The paper presents the test results of studies on the treatment of wastewater in experimental treatment facilities in a milk collecting station. The treatment process of wastewater was a follows: aeration-flocculation device -sedimentation pond - two-stage constructed wetlands. The laboratory investigations have shown that the primary treatment with quicklime (1 kg mE-3) reduces wastewater pollution by 54%, while the treatment with coagulant 'ZETAG 8660' (4 g mE-3) reduces it by even 68%. Such results were not obtained in the primary wastewater treatment stage under industrial conditions: biological oxygen demand (BOD5) in wastewater was reduced 27.2%, the amount of suspended sediment was reduced by 48.1%, the amounts of Ntotal and Ptotal decreased by 15.8% and 27% respectively. Such results much depended on the air temperature, inaccurate dosage of chemicals as well as on insufficient capacity of reaction and sedimentation reservoirs for 2.5 times higher amount of wastewater. However, despite such unfavourable conditions, this stage of treatment process was rather efficient: the pollution of wastewater with organic matter flowing into the stream did not exceed the maximum allowable rates. The average value according to BOD5 was 4 mg O2 lE-1, the highest BOD5 value was 9.6 mg O2 lE-1. From the environment protection point of view, it is particularly important that the removal of biogenic pollutants is quite sufficient in the wastewater treatment facilities. After the treatment process in wastewater treatment facilities, the amount of Ntotal decreased by 82.4% and the amount of Ptotal was reduced by even 97.3%.