Steam Recapture in Tissue Paper Drying via Exhaust Heat
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high energy costs associated with steam usage in tissue paper production, particularly in drying processes, necessitate a reduction in steam consumption from live steam networks to stabilize energy costs and maintain paper quality.
Innovation Solution
A device and method that utilize exhaust air from hot air hoods to vaporize condensate from heatable cylinders, compressing and re-injecting the generated steam back into the live steam network, reducing the overall steam demand and energy costs while maintaining stable drying conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If steam is used to heat the cylinder and dry the tissue paper web, then the drying effect is achieved, but energy costs increase
Solution Approach 1:
The patent recovers waste heat from the exhaust air of the hot air hood and uses it to vaporize condensate from the cylinder. This recovered energy is then fed back into the live steam network, reducing the need for additional steam and thereby lowering energy costs while maintaining the required drying temperature.
Solution Approach 2:
The patent converts the harmful waste heat in the exhaust air into a useful resource. The exhaust air, which would normally be discarded, is used to vaporize condensate and generate steam that is fed back into the network, turning an energy loss into an energy recovery mechanism.
2Productivity
If more steam is supplied to the cylinder, then the drying performance improves, but the stability of the live steam network is affected
Solution Approach 1:
The patent implements a feedback mechanism where the exhaust air from the hot air hood is used to vaporize condensate and the generated steam is fed back into the live steam network. This feedback loop stabilizes the steam network by returning excess steam to the network, preventing fluctuations and maintaining stable drying conditions.
3Loss of energy
If exhaust air is used to vaporize condensate, then steam consumption is reduced, but additional equipment is required
Solution Approach 1:
The patent makes the exhaust air system multi-functional by using it not only for its original purpose of drying the tissue paper web but also for vaporizing condensate and generating steam. This multi-functionality reduces the need for separate equipment, thereby reducing overall system complexity despite the added functionality.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces steam consumption by 1-3 tons per hour, lowering energy and production costs, and ensures stable paper quality by utilizing the live steam network as a buffer, preventing overheating and temperature fluctuations in the drying process.
Implementation Method 1
heating the condensate by heat exchange with the exhaust air from the hot air hood
Implementation Method 2
vaporize condensate from the heatable cylinder and to feed the steam produced in doing so
Implementation Method 3
compressing the condensate to a first pressure level according to that of the live steam network
Implementation Method 4
dried by the hot outer surface of the cylinder
Implementation Method 5
the tissue paper web being dried by both the hot outer surface of the cylinder and also the hot air
Data Source
AI summary
Method for steam recapture in the drying of a tissue paper web with a cylinder that is fed from a live steam network and with a hot air hood that flows hot air onto the tissue paper web, includes the steps of: removing condensate from the cylinder; compressing the condensate to a first pressure level essentially corresponding to that of the live steam network; heating the condensate by heat exchange with the exhaust air from the hot air hood; vaporizing the condensate; and feeding generated steam into the live steam network.