The initial situation
The initial situation was very easy, however. LEMKEN had already invested in a new in-hall air cleaning system not too long ago. However, the system did not meet the requirements, as the limit values could not be met and the halls filled with smoke. After many attempts at optimisation by the original manufacturer, it was decided to invest in a new system. So Kappa came into play.
The solution: The Kappa A.I.R.™ in-hall air cleaning system
In a first step, the existing steelwork hall was fitted with the Kappa A.I.R.™ in-hall air cleaning system. Whereby fresh air is introduced into the hall by Kappa Diffusers™ placed on the hall floor. Through the diffusion of fresh air, it is distributed without draught in the whole hall without mixing with the contaminated hall air. All obstacles are flowed around, and the employees are supplied with fresh air. A stable pool of fresh air was in the working area in just a short period of time. This actively displaces the released emissions and the waste heat from the work area and lounge area up towards the hall ceiling. There, the emissions and the waste heat is completely and extensively captured and led away with adjustable Kappa COC extraction plates. Filtration of the fine dust and smoke emissions takes place in the Kappa Mykron® fine dust filter. It ensures 30% better filtration of the finest particles compared to a conventional filter. The excellent filtration of fine dusts is also confirmed by the clean gas concentrations measurements with a clean gas value of 0.02 mg/m³. Due to the very high filtration efficiency of the Kappa Mykron®, the cleaned air can be fed back into the workplace.
The excellent performance of the Kappa A.I.R.™ in-hall air cleaning system is also confirmed by the measurements of TÜV Rhineland. According to them, the workplace concentration of A-dust (alveoli-penetrable dust) was just 0.12 mg/m³ and thus well below the newly raised general dust limit value of 1.25 mg/m³.
Due to the excellent results and experiences in the existing hall, the newly built production hall was also fitted with the Kappa A.I.R.™ in-hall air cleaning systems. It supplies the areas of cutting (oxygen cutting), steel construction and the warehouse. The emissions during flame-cutting are captured via the existing flame-cutting table and integrated into the exhaust air cleaning unit of the Kappa A.I.R.™ in-hall air cleaning system.
The function of the Kappa A.I.R.™ in-hall air cleaning system in the newly built hall is identical to the system already described above in the existing hall. In total for the existing and the new build, around 250,000 m³ of exhaust air are cleaned per hour at a high grade, and the halls are supplied with the same amount of clean fresh air. Due to the excellent filtration efficiency of the installed filter systems, the waste heat produced can be recovered with a high degree of efficiency by the integrated low temperature heat exchangers. A total of 2,173,764 kWh of waste heat can be recovered annually. It is used for heating the fresh air during the heating season.
What does the customer think?
Thomas Heenen, Safety Officer at LEMKEN, is impressed: "The air quality in the steel construction area is very good. This is also confirmed by our staff. Last winter we hardly had to heat at all, as we were able to cover our heat requirement from the heat recovered".
Automatic synchronisation of the output with the current demand saves energy:
Regulation of the air output of the in-hall air cleaning system in the existing hall and in the new steel construction hall takes place in sync with the corresponding demand. In phases with a high material throughput, the output of the in-hall air cleaning system is increased, and it is reduced in phases with lower material throughput. The actual output demand is regulated continuously. So the exact output needed is always available. Individual real-time adjustments are made possible by the Kappa Airdynamic™ system. It permanently monitors the emission load in the production area and regulates the air cleaning throughout the whole hall accordingly. Through the intelligent and needs-based system control by the Kappa Airdynamic™ system, 547,533 kWh of electricity can be saved annually.
"The system is fully automatic and reliable. When production increases, so do emissions, and the system responds immediately with an increase in performance. If the machines are not operating at full capacity, the performance of the air treatment system is automatically reduced", explained Karl Riegler, Technical Manager at Kappa.
Also, the required air output for the existing flame-cutting tables were fitted with a control system appropriate to the demand. This enables 259,067 kWh of electricity to be saved annually.
Steyr-Gleink, July 2016