DEAERATOR.SU has developed a proprietary technology designed to improve the reliability of district heating networks.
Official statistics put the average level of wear in Russian heat networks at 50-60 per cent. A technology already available on the Russian market can help address this problem. Commercial Director Mikhail Zhuchkov explains the operation and advantages of centrifugal droplet deaeration.
What is the fundamental operating principle of deaeration, and what are the technology's main advantages?
Water deaeration means removing dissolved oxygen from water. It is important to distinguish dissolved oxygen from air bubbles, which are normally released at the high points of a system.
Where deaeration is absent or ineffective, the wall thickness of heat-network pipes can decrease by approximately 0.5 millimetres per year. Corrosion is uneven, so inadequate deaeration is one of the principal causes of recurring failures in heating networks.
The technology has a broad field of application. It can be used wherever water treatment is required, including industrial boiler houses, district heating systems, district power stations, combined heat and power plants, thermal power stations and nuclear power plants.
The two most common approaches are thermal and chemical deaeration. Thermal deaeration is usually more economical because it avoids the continuing purchase of reagents. It requires the water to be brought to its saturation temperature: approximately 60-99°C under vacuum, 100-104°C at atmospheric pressure, and above 104°C when deaeration takes place under elevated pressure.
What determines whether chemical or thermal deaeration should be used?
The decision is mainly economic. Chemical deaeration can be effective and cost-efficient for heating-system flow rates of up to 5 tonnes per hour. Thermal deaeration is generally used at higher capacities. Our centrifugal droplet technology also allows us to manufacture deaerators rated as low as 1-2 tonnes per hour, enabling us to cover the full operating range.
Can the technology be applied both at new facilities and at operating sites? Does installation require a production shutdown?
We supply deaeration equipment for new-build projects and for the reconstruction or modernisation of existing plants.
For existing facilities, we offer a model that is interchangeable with standard deaeration columns. The customer can install it with a minimal amount of design and construction work, and in some cases without new design documentation at all.
One recent project required us to replace a boiler-feedwater deaerator without changing the surrounding pipework and while retaining an automation system installed in the 1960s. The old deaeration column was removed and a centrifugal droplet deaerator installed in its place. The customer obtained effective deaeration with minimal expenditure. The work can be performed without stopping the process cycle, and a column can even be replaced as part of routine maintenance without changing the existing design and operating documentation.
Does deaeration equipment create significant additional energy demand?
Every deaeration process consumes resources, but our technology is designed to improve the overall economics by reducing energy consumption and extending the life of equipment and networks. It achieves this through effective removal of dissolved gases across a wide load range.
What economic benefits can centrifugal droplet deaeration provide?
By reducing corrosion in equipment and pipelines, the technology increases the interval between repairs.
Additional savings are available when network-makeup deaerators at a combined heat and power plant are converted from atmospheric to vacuum operation, or when local boiler houses are converted to hot-water-only operation and vacuum deaeration. Under vacuum, the water boils at approximately 65-80°C, depending on the vacuum level, which reduces thermal energy consumption.
Only a limited number of manufacturers can achieve consistently good results in this operating range. Our technology enables deep vacuum operation and allows water at 65-70°C to be supplied to the deaerator. Combined with stable centrifugal droplet deaerator performance over a wide range of loads, this produces a substantial economic benefit.
For example, our calculations show that converting a 50 tonne-per-hour deaerator to vacuum operation can save RUB 5,101,824 in thermal energy per year.
The technology is therefore highly relevant to the Russian market. It addresses several industry challenges, including extending the service life of district heating networks. Importantly, it can protect not only new pipelines but also networks that are close to exhausting their design life.
Interview by Yefim Dubinkin.
