Operation and Maintenance

The Topas S 5 WWTP’s main energy consumer is a blower with a power input of about 60 W. Therefore, daily electricity consumption is 24 x 60 = 1.44 kWh/day, which amounts to 525.6 kWh/year. However, this is calculated if the blower works continuously all day/year. The Topas WWTP continuously measures wastewater quantity and automatically reduces air in the WWTP based on the amount of wastewater, leading to substantial energy savings without any maintenance. Therefore, real electricity consumption is much lower, as shown in the following table:
5 people1,4 kWh/ day1,2 kWh/day1,4 kWh/ day
3-4 people1,4 kWh/ day0,9 kWh/day1,1 kWh/day
1-2 people1,4 kWh/ day0,58 kWh/day0,8 kWh/day
0 people1,4 kWh/ day0,11 kWh/day0,14 kWh/day
Generally, the Topas WWTP can be temporarily overloaded up to double its designed capacity, both in terms of substance and hydraulics, for about 14 days. Activated sludge can bind pollutants into its cells and consume them later. In terms of hydraulics, the WWTP can handle more than double the flow. Prolonged overloading may lead to accumulation of pollutants in the activation volume, reducing dissolved oxygen and creating anoxic to anaerobic conditions. This can cause the complete die-off of activated sludge in the WWTP and collapse of the biological cleaning process. In such a case, it is usually necessary to evacuate the WWTP's contents and re-seed with new sludge.
Yes, it can. It is an aerobic biological wastewater treatment plant (WWTP) that is automatically adapted for reduced inflow of wastewater to maintain its biological function for as long as possible (by limiting aeration and supplementing substrates for microorganisms from the accumulation tank). The TOPAS S type WWTPs were tested for operational maintenance after 3 and 6 months of interrupted inflow. The testing was conducted by the Engineering Testing Institute Brno (SZÚ Brno). We initiated this testing based on the requirements of our Swedish and later Norwegian significant buyers of our domestic treatment plants, as required by local water authorities. Therefore, we had TOPAS S 7 and TOPAS S 10 WWTPs, supplemented with a sand filter and phosphorus removal dosing, which we commonly supply to these markets under the trade name TOPAS Plus (i.e., plus dosing), tested. The WWTPs were installed in the standard way and then completely cut off from the inflow. At one plant, the inflow was resumed after 3 months and at the other, after 6 months of interruption. Six samples were taken from both plants over 10 days after inflow resumption. The cleaning efficiency results were virtually the same in both cases. The outflow concentrations of treated wastewater from the WWTPs were within the limits required by national legislation for the given WWTP size in all six samples taken during the first 10 days after resumption of inflow. The average efficiencies achieved in the first 10 days were close to those achieved during CE certification. For this capability, tested by the testing institute, the TOPAS WWTP was awarded the Grand Prix at the international trade fair For Arch 2018 in Prague.
The membranes in the blower should be changed approximately every two years of the blower's operation. If the membranes in the blower are not replaced the risk of them bursting and potentially causing serious damage to the blower increases.
As with any other equipment the lifespan of individual parts of the WWTP varies. The main part of the WWTP, i.e., the actual plastic tank, including the roof and lid must meet a minimum lifespan of 25 years under the most unfavorable conditions to obtain the CE mark. In most cases, the lifespan will be even longer, typically 30, 35, or more years. The oldest plastic WWTPs of similar construction were produced before 1989 and are still in the ground.
  • In addition to the main structure, the WWTP consists of internal technology, which is usually plastic pipes, nozzles, and hoses that harden and become brittle over time. The lifespan of these components is about 10 years, after which all the technology can be quickly and easily replaced.
  • The aeration plastic membranes, which supply air to the water in the form of fine bubbles, have a shorter lifespan within the internal technology. The lifespan declared by the manufacturer is 10 years and they can be easily replaced.
  • Other mechanical components in the WWTP are electromagnetic membrane blowers and air solenoid valves. The lifespan of both the blower and valves is considered to be 8 years, although they often function for up to 15 years in practice.
  • Regular service of the blower should be accounted for, involving the replacement of coils every 4 years and membranes every 2 years.
If the WWTP is connected to any food production or processing facility, professional kitchen or restaurant it is the owner's responsibility to pre-treat the wastewater from these operations in a grease trap.
The noise level of the blower is guaranteed by the manufacturer at 38 dB. This value meets all sanitary standards for installation next to residential buildings. However, our installation under the WWTP cover reduces the overall noise level to barely audible. With the lid closed, the sound of water splashing is more noticeable than the operation of the WWTP itself. All Topas WWTPs meet noise limits. The basic limits for outdoor noise in residential areas are 50 dB during the day (6 am-10 pm) and 40 dB at night (10 pm-6 am).
Simply put, regular maintenance consists of an occasional visual check of the quality of the treated water after the lid of the WWTP is removed and then, after about 3-6 months (depending on the load), draining the sludge and cleaning the blower dust filter. Blower membranes need to be replaced every two years.