Our industrial kilns are specially designed to optimize energy efficiency by various means, one of the main opportunities being the recuperation of heat normally lost through the exhaust flue during the combustion process. With the goal of taking this a step forward – increasing the potential for the use and transfer of process heat – we have developed new technologies for our energy recovery systems (ERS).
These system enhancements allow the user to recover waste heat and to reuse it both in the kiln and in other plant processes, instead of simply exhausting it to atmosphere.
By reading the following article, you will learn more about these systems and the advantages they offer your production processes.
How do our kiln ERS systems work?
The energy that is introduced into the kiln via the burners is typically used to heat the following:
- Heating the kiln walls
- Heating the product
- Heating the kiln furniture
- Heating the kiln cars
The remaining energy is usually lost in what we term “loss to atmosphere”.
What our heat recuperation systems seek to achieve is the reuse of the energy carried by the gases that normally exit through the flue, in order to reduce gas consumption in a typical industrial heating process.
Example:
The temperature of the kiln’s discharge gases is 1000°C (1830°F), while when heat recuperation takes place we see this temperature reduce to 400°C (750°F), demonstrating that in reducing losses to atmosphere we are retaining more heat in the product/process, thereby achieving a more efficient operation.
This is extremely valuable for our customers, since an ERS can generate savings in energy consumption of 25% to 30%.
Heat recovery systems
At NUTEC Bickley we offer three types of kiln ERS, each with different capacities and costs, tailored to the individual customer’s requirements:
1. Heat Exchangers
Typically we install these in the kiln flues, where via an indirect heat exchange we are able to preheat kiln combustion air to temperatures up to 500°C (930°F).
A couple of advantages offered by this system are:
- The preheated air that is injected into the kiln is clean and can be used for the combustion process
- It can be used with all our combustion systems, including IMPS®
2. Self-Recuperative Burners
- This system achieves higher temperatures than preheated air produced via the heat exchanger method, reaching up to 750°C (1380°F)
- Unlike the system in which we employ a central heat exchanger, each self-recuperative burner has its own heat exchanger
- The energy savings over a system using a central heat exchanger are anything from 10% to 30%.
- Self-recuperative burners are compatible with our IMPS® system
3. Regenerative Burners
These represent the most efficient form of energy recovery in industrial kilns, as they can preheat combustion air to temperatures ranging from 900°C to 1000°C (1650°F to 1830°F).
These burners need to be installed in pairs. A limitation, however, on these burners is that they can only be used in applications characterized by high temperature and heat capacity.
Benefits offered by our ERS technology
NUTEC Bickley ERS prevents wasted energy and returns large quantities of energy back into the system, offering major advantages to our customers, such as:
- Systems compatible with all types of continuous and shuttle kilns
- Easy to maintain
- No adverse effects on product quality
- Operation with all Nutec Bickley combustion systems
- Dramatic reduction in energy costs
- Not only for use in new kilns, but also suitable for refurbishments
- NUTEC Bickley’s high-level expertise and reliable performance, plus its wide ranging experience in kiln construction.
