Drying Technology for Tissue
Yankee and MG Hoods
Based on the over 30 years experience in drying technology, Lario Energy, developed a new generation of high efficiency hoods to respond to tissue manufacturers’ new and higher identified needs and values.
Based on the concept of no fix contact points between the cold and hot sections of these hoods, for allowing the optimum thermal expansion without any stresses and/or deformations, the design is fulfilling, and achieved, the following benefits:
drying and energy efficiency optimization;
homogenous paper dryness due to the optimized nozzles matrix and geometry;
energy saving (thermal and electrical);
sheet stabilization and control of ballooning effect;
full control of the drying profile;
better drying paper edges control.
Lario’s high efficiency hoods are easily installed and adjusted, with a always perfect clearance between the Yankee dryer and the hood itself, due to our “curve” control construction method.
Lario can fully support its Customers (paper mills directly, as well as machine manufacturers) for revamping on existing machines or, complete new projects.
All our hoods are designed carefully looking at the safety, with a low maintenance concept and easy cleaning for improving the machines runnability and efficiency.
Each hood is dimensionally customized and can work with steam, gas and diathermic oil, following the Customer specifications and requests.
A gas heating system, with direct combustion in recirculating air stream, achieves the highest air temperature required for tissue production up to 700 °C.
For lower capacity applications, steam or diathermic oil can be used for air heating.
Two recirculation fans Duo System improves hood drying capacity and efficiency of heat recovery units and is widely used for high performance machine.
One recirculation fan Mono System can be proposed for medium and small size machine, particulary if steam heated.
Lario exhaust air heat recovery units are carefully studied to obtain the maximum of energy efficiency.
The first stage of recovery with air to air stainless steel heat exchanger is used for heating hood make up air and gas burners combustion air.
A second stage air to air heat exchanger can be used for machine building ventilation and heating.
A third stage air to water heat exchanger has the possibility to heat water for technological purpose or for machine building ventilation with glycol systems.
Lario steam and condensate system for MG and Tissue cylinders are based on the thermocompressor technology.
Design of the system is carefully studied case by case in order to assure the minimum steam consumption and the highest performances of drying capacity.
Can be proposed two steam and condensate system basic solutions related to the different type of boilers:
– direct pumping of hot condensate to the boiler ,
– pumping to the hot well or to the atmospheric vessel of low temperature condensate.
In both cases the aim is to obtain the minimum steam consumption values.
Lario thermocompressor system has been equipped with blow thru steam control BTC in order to optimize the siphons performance during production and paper break conditions.
The system can be controlled automatically with a dedicated PLC able to control warm up, start and stop of the system and the different production conditions and steam consumption.
The dust produced with the paper creping effect in the Yankee area is causing paper quality issues and fire risks.
The mist created at the wet end section of the machine is influencing the paper quality and the working are environment.
Lario Energy supplies customized solutions for minimizing the risks, quality and hygiene issues of the critical areas and improving the machine performances and efficiency.
Lario’s dust removal system is collecting the dust in all the critical points, with well dimensioned and proper shaped hoppers; a dust separator or a water cyclone are then cleaning the air expelled in the atmosphere.
The complete system is right balanced for complete removing the dust from the paper machines and/or rewinders, improving as well the web stabilization, with always the lower energy consumption.
The mist removal is designed for impeding the contact between humidity and dust, removing the mist and increasing the equipment lifetime together with a clean working area. Lario is using corrosion-resistant materials, that help to keep the system always in optimum working conditions.
Erection and start up of the systems are the final result of quality development, necessary to obtain the aim of each project.
A team of wide experience engineers can do supervision, calibration and set up of the system in order to assure the performance.
Lario take particular care of technical assistance and commissioning using frequently telecontrol systems.