Biological Anaerobic – Aerobic Treatment Of Dairy Wastewater In Poland
In 2014, farms across the EU-28 produced approximately 164.8 million tones of milk, of which 159.6 million tones (or 96.8 %) were cows’ milk. Cows’ milk production on farms was the highest in Bretagne (France), Southern and Eastern Ireland and Lombardia (Italy) and Masovia (Poland) (8,3%). Milk processing produces wastewater. In Poland 1 m 3 of processed milk accounts for 3.2 m 3 of wastewater. In 2013 the production of dairy products in Poland generated 26.5 hm 3 of sewage: 14.7 hm 3 of which was treated (9.3 hm 3 biologically and 5.4 hm 3 with increased nutrient removal). The dairy wastewater is primarily generated from the cleaning and washing operations. Its main contaminants are: high BOD and COD concentrations, and it contains fats, nutrients, lactose, as well as detergents and sanitizing agents. Biological treatment is the basic method used for wastewater from food processing. Dairy wastewater in Poland is treated using aerobic biological methods: circulated pond, activated sludge process, sequencing batch reactor, Moving Bed Biofilm Reactor and anaerobic reactors. The two steps anaerobic-aerobic reactors are used in two cases in Poland.
A review on anaerobic-aerobic treatment of industrial and municipal wastewater.
Anaerobic–aerobic systems have been remarkably employed in industrial and municipal wastewater treatment for many years. While previously most treatment of wastewaters have been carried out in conventional anaerobic–aerobic treatment plants, in recent years, high rate anaerobic–aerobic bioreactors have been increasingly employed for wastewaters with high chemical oxygen demand (COD). This paper provides a review of the various types of high rate anaerobic–aerobic water treatment techniques currently available including high rate bioreactors and integrated anaerobic–aerobic bioreactors. The integrated bioreactors are classified into four types, which are (i) integrated bioreactors with physical separation of anaerobic–aerobic zone, (ii) integrated bioreactors without physical separation of anaerobic–aerobic zone, (iii) anaerobic–aerobic Sequencing Batch Reactors (SBR), and (iv) combined anaerobic–aerobic culture system. The integration of aerobic and anaerobic degradation pathways in a single bioreactor is capable of enhancing the overall degradation efficiency. The merits of different integrated anaerobic–aerobic bioreactors are highlighted and comparison made to identify possible future areas of research to fully utilize these methods of wastewater treatment. The comparison demonstrates that using an integrated bioreactor with stacked configuration in treating high strength industrial wastewaters is advantageous due to minimal space requirements, low capital cost and excellent COD removal efficiencies (in excess of 83%).
Preparation and performance evaluation of swine manure bio-oil modified rubber asphalt binder
Abstract In order to study the effect of the preparation process of swine manure bio-oil modified rubber asphalt binder on the rheological properties of the binder, the matrix asphalt and asphalt rubber were used as the control group, and swine manure bio-oil modified rubber asphalt binders were obtained by three preparation processes. Then the rheological properties of five binders were evaluated by rotational viscosity, DSR, MSCR and BBR tests. The results show that the addition of swine manure bio-oil to asphalt rubber is beneficial to the workability, but cause negative effect on its high temperature performance, fatigue performance and low temperature crack resistance. The preparation method of premixing bio-oil and rubber powder can reduce the degradation of high-temperature performance of asphalt rubber caused by addition of swine manure bio-oil to a certain extent. The fatigue properties of the three bio-binders are close, and the critical temperature is less than 25 °C. The process of premixing bio-oil and rubber powder will increase the creep stiffness and reduce the low-temperature performance. However, the low-temperature performance of the binder obtained by this process is still better than that of the matrix asphalt and can meet the requirements of use. Therefore, it is recommended to use the preparation process of premixing bio-oil and rubber powder to prepare swine manure bio-oil modified asphalt rubber.