The largest producer in dairy industry in Germany required an upgrade of its wastewater treatment plant in order to comply with the required discharge standards. The volume of the dairy industry wastewater is 160 m³/day. This wastewater was highly polluted with milk, runoff from animal houses and chemicals from cleaning activities. A below ground modular solution was required that was simple to operate and that could be easily expanded in the future.
The dairy industry wastewater can be very highly polluted. High levels of BOD, COD, TSS means that cleaning the wastewater can require multiple process steps. In addition to this the ratio of carbon nitrogen and phosphorus is often not ideal for biological wastewater treatment for dairy industry. Because of this many companies offer a complicated multi process step solution for cleaning dairy industry wastewater.
Where multi step process technologies are used then the operation and maintenance of the wastewater treatment plant can become more complicated, with a full-time operator needed to monitor and control the system. The same can be said where anaerobic digestion is used to clean dairy industry wastewater. Well, there are some advantages to anaerobic digestion they’re outweighed by the sensitivity of the process and the need for a full-time operators to keep the system working efficiently.
In addition to this, the greywater from dairy industry can contain wastewater from multiple sources. This can be milk spillages and other product spillages, chemicals and cleaning agents from cleaning activities, and ran off from buildings where animals are housed. This can produce a highly polluted wastewater that is highly variable with regards to flows and loads.
The objective of the clients for this specific application was to identify a wastewater treatment solution for dairy industry could be installed mainly below ground, that would run automatically, and use a process technology that required minimal operator input. PPU is well established as a market leader in providing industrial wastewater treatment solutions in Germany, as we manufacture a wide range of solutions and process technologies we can select the best wastewater treatment solution for each individual dairy industry application based on client requirements.
The solution proposed by PPU was based on the fixed bed biological wastewater treatment process. Unlike many other biological wastewater treatment processes, the FBBR process has an ability to treat extremely high strength industrial wastewaters without any pretreatment using dissolved air floatation. Many competitor companies who looked at this project for offering dissolved air flotation as a pretreatment step.
The client of the dairy industry preferred not to use dissolved air floatation system in this instance due to the higher level of operator skill required, the additional chemicals required, and the need to have a separate sludge management system when installing a dissolved air floatation unit. When a fixed bed biological wastewater treatment process was demonstrated to the client, they were able to see the specialist process technology had the ability to clean their wastewater without the need for dissolved air floatation.
The first step in the process adjusted the pH of the wastewater and also adjusted the ratio of carbon nitrogen and phosphorus to provide ideal conditions for biological wastewater treatment. After this the wastewater is then fed to the biological wastewater treatment system. Here the fixed bed biological wastewater treatment is fed with equalized flow of wastewater. Supplying biological treatment steps with equalized continuous flow is very important as it provides good conditions for the biomass to develop and clean the wastewater.
Biologically treated effluent then enters the lamella clarifier and any of the remaining solids settle in the clarifier. The solids then removed by sludge return pump. Relative to other biological treatment process technologies such as MBBR & MBR, fixed bed biological process is far easier to operate, has lower running costs, does not require chemicals for cleaning, and does not use membranes. So overall the FBBR solution has the lowest OPEX on the market.
The final solution implemented on site for this project provides a very compact footprint with some of the system installed below ground. The system operates automatically with minimal use of chemicals and no need for continuous operator input. The system also cleans the wastewater completely biologically and naturally without the need for dissolved air floatation. The system was installed on time and on budget and allows the dairy industry to achieve compliance with their wastewater discharge standards.
flow: 160 m³/day