Air preheating is increasing system efficiency

Return on capital expected in two years

A new steam boiler system by Bosch Industriekessel recently went into operation at the premises of Slovenian paper manufacturer Paloma Sladkogorska. The system equipment includes the recently introduced APH air preheating system, a heat recovery device which Bosch launched on the market in July this year. It reduces the flue gas temperature of the boiler by preheating the combustion air, thereby increasing system efficiency.

The air preheating system is available for single or double flame tube steam boilers with duoblock burners. It is recommended for use in applications in which process conditions mean that it would not make sense to include a flue gas condenser. On account of its special hydraulic circuitry, the system has far fewer components than commercially available two-circuit systems. It consists of a three-way valve, a combined flue gas heat exchanger and an air-side heat exchanger. If double flame tube boilers such as the one at Paloma are used, the system features two air-side heat exchangers.

A part of the hot feed water is directed to the air-side heat exchangers via the three-way valve. This preheats the combustion air for firing and reduces the temperature of the feed water. The downstream flue gas heat exchanger recovers heat from the hot boiler waste gases as a result of the cooled feed water partial flow reducing the flue gas temperature. The efficiency of the boiler system is up to two percent higher, whilst fuel consumption and emissions are lower.

The ZFR gas-fired boiler produces approximately 30 tons of steam per hour in the paper factory. An integrated superheater module on the boiler generates superheated steam instead of saturated steam, as a result of which temperatures of up to 285 degrees Celsius can be reached. The steam is required for production processes such as drying paper rolls. Every year, Paloma produces hygiene products including toilet paper, tissues, paper towels and napkins from approximately 70,000 tons of paper.

Thanks to the BCO boiler control, operation is user-friendly and settings can be tailor-made according to demand. Integrated fault messaging management, along with troubleshooting support via Bosch Teleservice, make for seamless operation.

Previously, Paloma was using a steam turbine and a 30-year-old water tube boiler. The absence of heat recovery devices meant that significant potential for savings was not being tapped into. With the new Bosch boiler system with economizer and air preheating system, the paper manufacturer now has an energy generation system at its disposal that is optimised in terms of both economic efficiency and the environment. With continuous operation, return on capital for the total investment should be seen in approximately two years. The Slovenian company C. P. Biro, a long-term partner of Bosch, was responsible for all aspects of project support locally.

Bosch Industriekessel GmbH, part of the Bosch Thermotechnik GmbH, has stood for innovation in industrial boiler technology for more than 145 years. Boiler systems for steam, hot water and heating, manufactured to customers' specification, provide efficient heating and process heat for all applications. Boiler house components, which are modular in design and perfectly coordinated, together with intelligent regulation and control technology, significantly simplify the planning, installation and commissioning of the complete system. Comprehensive service support from one source rounds off the innovative product portfolio.

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The Bosch Group is a leading global supplier of technology and services. In fiscal 2012, its roughly 306,000 associates generated sales of 52.5 billion euros. Since the beginning of 2013, its operations have been divided into four business sectors: Automotive Technology, Industrial Technology, Consumer Goods, and Energy and Building Technology. The Bosch Group comprises Robert Bosch GmbH and its roughly 360 subsidiaries and regional companies in some 50 countries. If its sales and service partners are included, then Bosch is represented in roughly 150 countries. This worldwide development, manufacturing, and sales network is the foundation for further growth. Bosch spent some 4.8 billion euros for research and development in 2012, and applied for nearly 4,800 patents worldwide. The Bosch Group's products and services are designed to fascinate, and to improve the quality of life by providing solutions which are both innovative and beneficial. In this way, the company offers technology worldwide that is "Invented for life."

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Tags: Efficiency, Air

Bosch Thermotechnology is a leading European manufacturer of energy-efficient heating products and hot water solutions. In fiscal 2018, the company generated sales of about 3.5 billion euros (66 percent outside Germany) and employed approx. 14,200 people. Bosch Thermotechnology has strong international and regional brands and manufactures a diversified product range in Europe, America and Asia.

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The Bosch Group is a leading global supplier of technology and services. It employs roughly 410,000 associates worldwide (as of December 31, 2018). The company generated sales of 78.5 billion euros in 2018. Its operations are divided into four business sectors: Mobility Solutions, Industrial Technology, Consumer Goods, and Energy and Building Technology. As a leading IoT company, Bosch offers innovative solutions for smart homes, smart cities, connected mobility, and connected manufacturing. It uses its expertise in sensor technology, software, and services, as well as its own IoT cloud, to offer its customers connected, cross-domain solutions from a single source. The Bosch Group’s strategic objective is to deliver innovations for a connected life. Bosch improves quality of life worldwide with products and services that are innovative and spark enthusiasm. In short, Bosch creates technology that is “Invented for life.” The Bosch Group comprises Robert Bosch GmbH and its roughly 460 subsidiary and regional companies in over 60 countries. Including sales and service partners, Bosch’s global manufacturing, engineering, and sales network covers nearly every country in the world. The basis for the company’s future growth is its innovative strength. At nearly 130 locations across the globe, Bosch employs some 68,700 associates in research and development.

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