Zero Emission Process Steam Generator (ZGPT)
Currently available and operational systems used for process steam generation are typically based on technologies in which the steam-producing source consists of flame-tube/smoke-tube boilers or water-tube boilers.
In such systems, a significant portion of the generated thermal energy (and often the entire amount) is lost due to cooling—either of the process steam itself (as it must be condensed) or of the medium heated by the process steam during industrial operations, which then needs to be cooled (e.g., to ambient temperature).
The energy flow in conventional systems is illustrated below in the Sankey diagram.
The response to market needs is our developed and patented technology of the Zero Emission Process Steam Generator (ZGPT).
Despite its innovativeness, the ZGPT system is simple in its construction. It is designed for generating process steam used in industrial operations. The system consists of well-known technical components such as heat exchangers, pumps, and compressors. This approach makes the offered technology reliable and easy to operate. The ZGPT system operates based on reversed thermodynamic cycles, similar to those used in heat pumps.
The key feature that distinguishes ZGPT from conventional technologies is that the system’s output is not heated water, as in typical heat pumps, but process steam, which supplies industrial processes at the plant.
The ZGPT system draws its energy mainly from waste heat generated in industrial processes, significantly reducing the need for primary fuels or primary energy. The offered technology can be implemented in various configurations—for example, with a single reversed thermodynamic cycle using water (R718) as the working fluid. A schematic of such a system is presented below.
In the solution presented above, the waste heat recovered from the process cooler is of sufficiently high temperature that no additional temperature increase is required to evaporate water in the steam generator. In cases where the temperature of the waste heat recovered from the process cooler is too low to directly produce process steam in the steam generator, an intermediate system and an additional (second) reversed thermodynamic cycle can be applied. A key feature of this system is the use of a working fluid with a low boiling point. A schematic of such a system is presented below.
It should be noted that in both of the solutions presented above, the generation of process steam in the steam generator takes place under significant vacuum conditions, which means the process occurs at a temperature of approximately 60–75°C.
Waste heat, which would normally be lost in cooling processes, is reused in the ZGPT system for steam production, creating a closed energy loop and minimizing water consumption in cooling systems.
Since the driving energy of the system is electricity—which can be sourced from “green” energy—the system becomes zero-emission and fully decarbonized.
The energy flow in the ZGPT system is illustrated below in the Sankey diagram.
Thanks to the full automation of the Zero Emission Process Steam Generator system, continuous 24-hour operator supervision is not required, which also contributes to reduced operational costs for the facility.
Main advantages of the Zero-Emission Process Steam Generator:
- Possibility of full zero-emission operation through the use of reversed thermodynamic cycles, waste heat, and electricity sourced from renewable energy (RES).
- High coefficient of performance (COP) at a level of 3 (ranging from 2 to 4), meaning the system generates three times more energy in the form of steam than it consumes in electricity, making it highly energy-efficient.
- Reduction of carbon footprint, supporting climate goals and enhancing the company’s image.
- Reduced water consumption through efficient use of energy from cooling processes, directly aligning with the principles of the circular economy (Blue Deal).
- Transition of the facility to a circular economy model.
- No need for continuous operator supervision due to full automation of the steam production process.
- Reduced staffing requirements thanks to full automation, absence of combustion processes, and the use of standard technical components.
- Short payback period ranging from 2 to 4 years, depending on reference costs.
- Cost stabilization and predictability in energy production.
Additional information on the Zero Emission Process Steam Generator can be found in the “Products – ZGPT” tab.
