The EKOMVO aeration system is designed for aerating and hydraulically mixing liquids in tanks. It is primarily used in municipal and industrial wastewater treatment plants, and it also finds practical application in intensive fish farming.

Oxygen is transferred into the wastewater through a suitable aeration membrane with fine or medium-bubble perforation, depending on requirements. The membrane material is a modified polyurethane, specifically developed to resist the effects of microorganisms and hydrolysis. Intensive aeration is essential in the biological treatment of wastewater to provide sufficient oxygen for the biomass of microorganisms, which decompose pollutants through their metabolic activity and thereby ensure the purification process.

The membrane is manufactured with a thickness that ensures long-term durability while maintaining a high oxygen transfer efficiency. These performance characteristics, combined with the use of suitable anchoring and fastening materials, guarantee the long service life of the system.

The EKOMVO system is suitable not only for the construction and implementation of new wastewater treatment plants but also for the reconstruction or upgrading of existing facilities.

An important advantage of this system is its very easy installation and subsequent maintenance. These aeration systems do not require acid cleaning and, thanks to their self-draining design, do not need any additional drainage systems for condensate removal. During operation, the condensate is continuously expelled from the system into the tank space by the working air.

The anchoring system itself (polypropylene grates) is virtually unaffected by operational wear and tear, with a lifespan that exceeds the expected service life of the system. The manufacturer recommends replacing the aeration membranes after approximately five years of continuous operation. After this period, the oxygen yield curve begins to shift, which may result in increased energy consumption required to operate the air blowers.

Types of Aeration Elements

Currently, we supply aeration systems with the following types of diffusers:

• Disc diffusers – Disc diffusers are mounted on a grid fixed to the bottom of the tank. These grids are most commonly made from PE pipes. The discs are connected to the grid using a threaded joint with integrated sealing. These grids are equipped with piping for condensate drainage.
• Tube diffusers – Tube diffusers are mounted on a main distribution pipe anchored to the tank bottom. The main pipe is usually made of stainless steel profiles, and the tubes are typically installed in opposing pairs. The connection of the tubes to the main pipe is made with a threaded joint including sealing. These systems are also fitted with piping for condensate removal.
• Membranes on grates – The membranes are stretched over PP grates in sets of 2, 4, or 6 units. The length of the grates and the number of membranes depend on the tank’s design and the required oxygen transfer capacity.

Types of Aeration Membranes

Currently, we supply aeration systems with the following types of diffusers:

• Polyurethane membranes – These membranes are particularly known for their durability. Polyurethane membranes can be used with both grate-mounted and tube diffusers.
• EPDM membranes – Durable membranes used with disc and tube diffusers. Their main advantage is an excellent price-to-performance ratio.
• EPDM membranes with a Teflon layer – Membranes with a Teflon surface coating, designed for use with disc and tube diffusers.

Types of Aeration Grates Based on the Number of Membranes

• Grate with two hoses, designation EV length – 2/400 – The center-to-center distance between the two aeration membranes is 400 mm. The maximum length of the aeration grate is approximately 15 meters with a single 65 mm air inlet. For lengths exceeding 15 m, a greater number or larger diameter of air inlet pipes must be used.
• Grate with four hoses, designation EV length – 4/200 – The center-to-center distance between the four membranes is 200 mm. If the grate length exceeds 7.5 meters, the number or diameter of air inlet pipes should be adjusted accordingly.
• Grate with six hoses, designation EV length – 6/200 – The center-to-center distance between the six membranes is 200 mm. For grate lengths exceeding 3.7 meters, an adequate number or increased diameter of air inlet pipes is required.

Anchoring Methods for Aeration Elements

The anchoring method of EKOMVO aeration elements depends on the installation setup. Individual grates can be installed in the following ways:

• Fixed anchoring – The aeration system is anchored to the tank bottom using stainless steel screws and plastic plugs, or chemical anchors. The screws (or chemical anchors) secure the grates to the floor using special stainless steel clamps, which can also serve to compensate for any unevenness of the tank bottom.
• Ballasted anchoring – The aeration grates are placed directly on the tank floor without anchoring components. The main pipe of the aeration grate is filled with ballast material so that each element is sufficiently weighted to resist hydraulic uplift. These grates can be installed or removed during operation without emptying the tank.
• Floating anchoring – The aeration grates are secured to the tank bottom with a system of stainless steel cables and guide sleeves. In working position, the grates are pulled down to the tank floor. If removal during operation is needed, a dual-direction winch with an automatic clutch releases the cables and the grate floats to the surface. Reinstallation is done by reversing the process.

Service Life of the EKOMVO System

The general service life of the EKOMVO system is divided into two main groups:

• Group 1:
  Parts not subject to operational wear
  This includes: the complete construction of the aeration grate made from injection-molded polypropylene, the entire anchoring system, and the air supply piping. The service life of these non-wearing parts is at least 15 to 20 years.
• Group 2:
  Parts subject to operational wear
  This group includes the aeration membranes with fine-bubble or medium-bubble perforation. Due to wear and tear of the perforation, it is generally recommended to replace the membranes approximately every five years, as reduced oxygen transfer efficiency into wastewater can be expected after that period. However, the membranes may last up to 8 to 10 years depending on specific usage conditions and the operating environment.

System Drainage

The EKOMVO aeration system does not require the installation of an additional condensate drainage system. Any water condensate that may form under certain conditions is discharged during operation through the membrane perforation. The internal structure of the air distributor, where the nozzles for aeration membranes are tangentially welded to the transverse air distributor, enables unobstructed flow of condensate into the membrane.

Service

Service operations and the supply of spare parts during the warranty period are provided by EKOMVO s.r.o. upon prior request from the system operator and based on mutual agreement.

After the warranty period, EKOMVO s.r.o. automatically offers each operator the option of signing a Service Agreement, under which the company provides—according to the agreed terms—necessary spare parts, periodic inspections, servicing, and consulting. This service can be contractually arranged either periodically or on demand.

Technical Parameters of the Aeration System

• Pressure loss depending on air load of the aeration hose
  (Hose diameter: 65 mm, perforation density: 168 holes/100 mm of hose, submersion: 440 mm from hose axis, hole diameter: 4 mm, hose width when lightly compressed: 100.2 mm, average wall thickness: 0.59 mm)

load (m³/h/m)	pressure drop (mbar)			air flow rate (m³/h/m)	pressure drop (mbar)			T (mm)
	ascending	descending	diameter		ascending	descending	diameter
1,5	46,8	47,5	47,15	5	70,5	69,2	69,85	0,61
2	50,7	50,9	50,80	5,5	73,1	71,7	72,4	0,57
2,5	54,2	54,5	54,35	6	75,5	73,9	74,7	0,59
3	58	57,5	57,75	6,5	77,3	76	76,65	0,58
3,5	61,6	60,5	61,05	7	78,9	78	78,45	0,6
4	64,9	63,7	64,30	7,5	80,8	80	80,40	0,61
4,5	67,9	66,5	67,20	8	82,6	82,6	82,6
diameter	57,73	57,30	57,51		76,96	75,91	76,44	0,59
rozdíl maximum – minimum					35,8	35,1
average pressure drop at a load of 1.5 – 8 m³/h			66,98	average difference between loads of 1,5 – 8 m3/h			35,45
average pressure drop at a load of 4 m3/h			64,3	average difference between loads of 4 m3/h			16,95

• Oxygen utilization (OC): approx. 4.0 kg O₂/kWh
• Percentage oxygen utilization: approx. 6% per meter of immersion depth
• Alpha value: 0.7 – 0.8
• Theoretical air loading per linear meter of membrane: 1 – 20 m³/m·h
• Operational air loading per linear meter of membrane: 1.5 – 6 m³/m·h