Content Series: Landscape Park Duisburg-Nord: A living piece of LESER history
The Landscape Park Duisburg-Nord is a worldwide unique natural and cultural landscape. For more than 25 years, the site of the former 180-hectare steel mill has offered a wide variety of sporting, cultural or professional uses. Regular Corporate and cultural events are hosted in former production halls. An old gasometer is home to Europe's largest artificial diving center. A viewpoint on a disused blast furnace allows a view into the distance.
Slowly but surely, nature is reclaiming the old industrial sites.
A symbiosis of urban nature and industry
Today, plants and animals have rediscovered the
place as their habit and found a home between blast furnaces, smokestacks and
steel girders. Step by step, nature has reclaimed the area. The result: a unique synergy of urban nature and the
industrial heritage of the Ruhr region, which the British newspaper
"The Guardian" recently ranked among the ten most beautiful
metropolitan oases in the world.
The Landscape Park Duisburg-Nord, also called
"LaPaDu" by locals, is so massive that it would take hours to fully
explore the area. Large parts of it are
open to the public and invite technology and industry enthusiasts to
discover the steel testimonies of an industrial landscape of the last century.
LESER safety valve of type 541 exhibited at LaPaDu
LESER is part of this
cultural heritage
In the midst of this special place, LESER
employees Stefan Lange, Eckhard Stüber and Holger Gesche recently came across
old LESER spring-loaded full lift safety
valves of Type 541, the predecessor model of Type 441, which was has been
in use since 1978. They visited the landscape park to attend the 10th PRIINT:DAY 2020/2021, the largest event
for multichannel publishing in Germany.
In
fact, the entire plant was once protected against overpressure by LESER valves -
some of them still contribute to the industrial
charm of the landscape park today and can be seen on site. Prominently
displayed with matching blue light, the valve pictured here, is even exhibited for
visitors of the landscape park.
Stefan Lange, Manager Marketing Communicationsin front of a LESER safety valve at LaPaDu
Part 2: Type 541 - The “flower
pot”
Unlike its successor, the Type 541 safety valve
installed at Landscape Park Duisburg-Nord had a full-lift accumulator chamber
whose distinctive shape reminds of a flowerpot. Safety valves of this design
were therefore given the descriptive nickname “flower pot”. The characteristic
sump disappeared as the valve was further developed. A key advantage of the
product innovation of 1978 was the solid connection between the disc and the
lifting aid. By that its function within the requirements of the applicable
codes and standards could be better ensured. The drainage option for the
accumulator chamber included in the Type 541 became obsolete as a result of
this innovation. Many of the proportional and special valves developed by LESER
in the following years are based on the success formula of Type 441.2
Cross-sections of Type 541 "flower pot" (left) and Type 441 exhibited at the LESER museum
In the museum inside the LESER Kontor, the
differences between the two models can be recognized by looking at their
cross-sections. The book "175 Jahre
Gebr. Leser, G. Wittmann Nachf: 1818 - 1993 ; Armaturenfabrik, Hamburg &
Hohenwestedt ; Geschichte und Geschichten eines Hamburger Familienunternehmens",
which is also exhibited there, provides interesting insights into the
development of the Type 441, and the crucial innovation it represents for the
LESER company.
Safety Valves next to the blast furnace
Part 3: What were LESER safety valves used for at LaPaDu?
Iron does
not occur in nature as elemental iron, but in oxide compounds. To obtain elemental iron for further processing in
steel production, the oxygen contained in the iron ore must be separated from
the iron in a chemical redox reaction. To separate the oxygen, iron ore is brought into the blast furnace
from above together with coking coal and other aggregates. Heating the
mixture in different temperature zones causes the oxygen to separate from the iron, which can finally be "tapped
off" at the bottom of the blast furnace and be used for steel production.
In addition
to the blast furnace, metallurgical plants such as LaPaDu consist of other components, such as the so-called
"bunker" which is used to store iron ore and aggregates, as well as transport and piping systems. The overpressure protection is therefore of
high importance in this context. LESER safety valves were and still are
used for a whole range of applications to ensure overpressure protection around
blast furnaces. Some examples are the systems
for the introduction of compressed air and the supply of cooling water.
The blast furnace in the focus of climateprotection
The process explained here, which has been further developed over centuries, is
still used for a large proportion of the worldwide steel production. Iron and
steel production using coking coal causes
a high amount of emissions. Coking coal, which has been used in the past
and still is used for heating up blast furnaces as well as a reducing agent
until today, burns at very high temperatures. In the course of processing the
iron ore, chemical processes also cause
large quantities of climate-damaging gases to be released into the atmosphere
– especially CO2. The production process for one ton of crude steel emits
around 1.7 tons of CO2.2 Therefore, in Germany the steel production industry currently
accounts for approximately 30% of the country's total industrial CO2 emissions.3
Part 4: The future of steel production
In the wake of climate change, the German government made amendments to the Climate Protection Act in summer 2021. In the future the steel industry will have to significantly reduce its CO2 emissions. Therefore, last summer, top representatives of the major German steel companies, the German Steel Federation (Wirtschaftsvereinigung Stahl) and the German metalworkers' union IG Metall met with former German Minister Peter Altmaier to drive forward the implementation of the so-called „Handlungskonzept Stahl“ which had been introduced already in 2020. A central lever of the concept is the conversion of production to low-CO2 and climate-neutral technologies in the long term.
Point 10 of the action plan envisages a gradual reduction in the use of coking coal for steel production and a switch to hydrogen. This conversion is only possible because of the chemical properties of hydrogen as it is suitable for direct reduction of the iron ore used. The high-emission production of liquid pig iron is no longer necessary with this process. Instead, direct reduction using hydrogen produces a solid, so-called "sponge iron" which is refined into crude steel in electric arc furnaces. If "green hydrogen" generated with the aid of renewable energies is used to produce the required hydrogen, it is even possible to produce steel in a virtually climate-neutral way. 4
For this reason, new steelmaking plants are to be designed from the outset to allow the use of hydrogen in addition to natural gas. According to the concept, this applies "not only to "first of it's kind" projects, but to the conversion process as a whole." 5
Overpressure protection in hydrogen-based steel production
LESER acts proactively in this dynamic market environment and supports customers and partners in overpressure protection along the entire hydrogen value chain. This includes the following application scenarios, among others: 1. Hydrogen production (e.g. electrolysis plants) 2. Distribution (e.g. hydrogen filling stations) 3. Hydrogen in the natural gas grid 4. Use of hydrogen:
Fuel cells (e.g. for heat and power generation)
Steel production (e.g., in blast furnaces as a blow-in coal substitute and reducing agent)
Chemical industry (e.g. for the production of ammonia or methanol)
Hydrogen as a coolant (e.g. in power plants)
Hydrogen as future energy storage
Within the scope of numerous pilot projects, LESER safety valves have already been successfully used for overpressure protection of hydrogen applications. The video shows, for example, the Vattenfall hydrogen filling station at the Oberbaumbrücke in Hamburg. The following hydrogen information sheetprovides further details on the subject of hydrogen and the applications of safety valves in this context.
The Landscape Park Duisburg-Nord impressively combines nature and industry, work and life, old and new. It is one of the few places where old LESER safety valves can still be viewed in their original application environment. It also allows a glimpse into the future of LESER valve applications in a more climate-friendly steel production.
This is the end of our four-part content series "LaPaDu" and journey from the past of steel production to the future overpressure protection of hydrogen applications. If you have any questions about the content or the potential applications of LESER safety valves along the hydrogen value chain, feel free to contact us at sales@leser.com.
2 Leser, W. (1993): 175 Jahre
Gebr. Leser, G. Wittmann Nachf: 1818 - 1993 ; Armaturenfabrik, Hamburg &
Hohenwestedt ; Geschichte und Geschichten eines Hamburger Familienunternehmens.
Hamburg: Leser.
