Industrial-scale Plant Research Articles

Applying Nanofiltration to Decrease Energy Consumption and Sensitivity toward Feed Composition Fluctuations in Salt Production.

The only currently active industrial-scale plant that uses coal mine brines, located in Czerwionka-Leszczyny, uses ZOD (Zakład Odsalania Dębieńsko, the name of the plant's former owner) technology, based on mechanical vapor compression evaporators. The plant produces evaporated salt that meets the specifications for edible salt; however, the technology is highly energy-consuming. The presented work focuses on the modeling of ZOD technology if applied to the water treatment of the 'Ziemowit-650' coal mine. Using the results of bench-scale investigation of brine nanofiltration and a mathematical model of ZOD technology based on Czerwionka-Leszczyny performance, the energy consumption per ton of produced salt was estimated for two cases: (1) ZOD technology treating the 'Ziemowit-650' brine and (2) ZOD technology treating the permeate of nanofiltration (NF) working on the 'Ziemowit-650' brine. The sensitivity of the system was investigated in the range of -10% to + 10% of Cl-, SO42-, Mg2+, and Ca2+ concentration, assuming that the sodium concentration also changes to meet the electroneutrality requirement. The results show that nanofiltration pretreatment not only decreases energy consumption but it also makes salt production less sensitive to fluctuations in feed water composition.

Fly ash as a cost-effective catalyst to promote sorbent regeneration for energy efficient CO2 capture

The use of catalysts to promote sorbent regeneration is currently considered an effective method to reduce the energy required in CO2 capture processes. Aiming at identifying stable and cost-effective catalysts with high CO2 desorption efficiency, here we investigated the performance of fly ash (FA) during thermal regeneration of aqueous amine solutions. The desorption rate, cyclic capacity and heat duty of a CO2-saturated aqueous ethanolamine with the addition of FA were experimentally measured, and the results were compared with those obtained for the same solution without and with eight different catalysts. Experimental results showed that catalysts significantly improved the regeneration compared to the non-catalyzed system, and FA was the most efficient of these. Further studies of CO2 desorption at different temperatures showed that FA provided desorption performance comparable to that of the non-catalyzed system at temperatures at least 5 °C higher and always significantly reduced the heat duty at the same temperature, especially at the beginning of the process. Finally, recycling tests demonstrated that FA had good stability and its catalytic efficiency remained high even after 20 cycles. In conclusion, FA could be considered a cost-effective catalyst for energy-efficient CO2 capture, deserving further investigation to promote its application in industrial-scale plants.

The role of chemical and solvent-based recycling within a sustainable circular economy for plastics

Chemical and solvent-based recycling of plastic waste may help overcome some of the challenges faced by predominantly applied mechanical recycling techniques. This study quantifies the environmental impacts of chemical and solvent-based recycling as a function of varying process parameters and product composition using life cycle assessment. Furthermore, potential benefits and impacts on a system level are determined. To that end, a high-resolution material flow analysis is conducted for the reference system of Switzerland, covering all main plastic types and applications. In a scenario for the year 2040, we employ environmentally beneficial mechanical recycling where possible and convey suitable remaining waste streams to chemical or solvent-based recycling processes. Applying chemical or solvent-based recycling as a complement to maximum mechanical recycling, instead of thermal treatment with energy recovery, may achieve a reduction in the climate change impact of the system ranging from less than 10 % to almost 40 %. For achieving high environmental benefits, proper process choice and configuration are crucial. Dissolution or depolymerization provide higher benefits relative to other chemical recycling processes, but can only treat certain waste streams and require prior sorting into plastic types. Pyrolysis and gasification appeared to only have the ability to achieve substantial benefits over incineration if their output products can substitute high-impact chemicals and provided that efficient heat transfer and recovery is warranted when implemented on a large scale. As industrial-scale plants for chemical or solvent-based plastic recycling are still lacking, the upscaling potential and the environmental benefits achievable in practice are highly uncertain today.

Analytical and numerical characterisation of terminal velocities of Tenebrio molitor larvae in a new, asymmetrical zigzag based separation system

Abstract Separation of Tenebrio molitor larvae from unwanted residues, like frass, feed or exuviae is a key process step for an industrial scale plant. One method to separate larvae from residues is using a zigzag air classifier. For designing and for an efficient operation of a zigzag air classifier, the terminal velocity is a key parameter to separate larvae from different residues with a high separation sensitivity. In this work, the terminal velocities of different larvae sizes are evaluated analytically, numerically and experimentally. For this, the sizes of 3 week to 12 week old larvae were used to calculate and simulate the terminal velocity. To validate the results, an experiment was carried out and compared with the analytical and numerical data. For this, a model for T. molitor larvae was designed to calculate the surface and volume of a larva to produce equivalent spheres with the same physical properties as a real larva. The results are showing similar curves with terminal velocities from 5 m/s for young larvae (3 weeks old) to 12 m/s for older larvae (12 weeks old). The deviations between each method are 1 m/s for smaller larvae and 1.5 m/s for bigger larvae. In further experiments and simulations, approaches with calculation methods for non-spherical particles are necessary to achieve results closer to reality due to the cylindrical shape of T. molitor larvae.

Technical, economic and environmental analysis of solar thermochemical production of drop-in fuels

This study analyzes the technical performance, costs and life-cycle greenhouse gas (GHG) emissions of the production of various fuels using air-captured water and CO2, and concentrated solar energy as the source of high-temperature process heat. The solar thermochemical fuel production pathway utilizes a ceria-based redox cycle for splitting water and CO2 to syngas – a tailored mixture of H2 and CO – which in turn is further converted to liquid hydrocarbon fuels. The cycle is driven by concentrated solar heat and supplemented by a high-temperature thermal energy storage for round-the-clock continuous operation. The study examines three locations with high direct normal irradiation using a baseline heliostat field reflective area of 1 km2 for the production of six fuels, i.e. jet fuel and diesel via Fischer-Tropsch, methanol, gasoline via methanol, dimethyl ether, and hydrogen. Two scenarios are considered: near-term future by the year 2030 and long-term future beyond 2030.In the near-term future in Sierra Gorda (Chile), the minimum fuel selling price is estimated at around 76 €/GJ (2.5 €/L) for jet fuel and diesel, 65 €/GJ for methanol, gasoline (via methanol) and dimethyl ether (DME), and 42 €/GJ for hydrogen (excluding liquefaction). In the long-term future, with advancements in solar receiver, redox reactor, high-temperature heat recovery and direct air capture technologies, the industrial-scale plant could achieve a solar-to-fuel efficiency up to 13–19 %, depending on the target fuel, resulting in a minimum fuel selling price of 16–38 €/GJ (0.6–1.3 €/L) for jet fuel and diesel, and 14–32 €/GJ for methanol, gasoline, and DME, making these fuels synthesized from sunlight and air cost-competitive vis-à-vis e-fuels. To produce the same fuels in Tabernas (Spain) and Ouarzazate (Morocco) as in Sierra Gorda, the production cost would increase by 22–33 %. Greenhouse gas savings can be over 80 % already in the near-term future.

Environmental sustainability of microalgae-based production systems: Roadmap and challenges towards the industrial implementation

Microalgae and cyanobacteria are a precious source for the production of biofuels/bioenergy, biomaterials and valuable biochemicals. Beyond photosynthetic CO2 conversion, microalgal systems can involve the valorisation of waste streams and the implementation of green chemistry, industrial symbiosis, and circular bioeconomy approaches. However, their sustainability is uncertain, thus their large-scale application is hindered. The numerous life cycle assessments (LCAs) performed so far are mostly based on data extrapolated from lab-scale experiments or the literature, leading to qualitative and controversial results. This paper reviews primary data-based LCA studies on microalgal pilot to industrial-scale plants. Sixteen studies satisfied the selection criteria, despite they used primary data almost exclusively for cultivation and harvesting. The outlined current status (methodology, inventory, energy performance and environmental impacts) highlighted the lack of uniformity in the applied methods and the presentation of results, as well as some lack of transparency. Nevertheless, the review concluded that electricity consumption and infrastructure are major hotspots. Therefore, the use of renewable energy for supplying the process and of sunlight for biomass photosynthesis should be preferred. The upstream processes produce large impacts. Thus, a suitable reactor, geographic location, and harvesting method should be selected. Biofuels are not competitive in most cases, but some promising multi-product biorefinery scenarios have been presented. To improve the environmental profile of microalgal high-value compounds (e.g., astaxanthin or biostimulants), co-product valorisation, waste stream utilization, renewable energy deployment, and compound productivity should be enhanced. More efforts on LCA of large-scale plants are required, especially looking at integrated biorefinery concepts, to take a crucial step towards the implementation of sustainable commercial systems.

Molten salt strategy to activate biochar for enhancing biohydrogen production

Generally, dark fermentation (DF) of hydrogen (H2) synthesis has low H2 production from industrial-scale plants. In this study, campus greening wastes-ginkgo leaves were used to produce molten salt-modified biochar (MSBC) and nitrogen (N2)-atmosphere BC (NBC) in molten salt and N2 environment at 800 °C, respectively. MSBC showed excellent properties including high specific surface area and electron transfer ability. After supplementation with MSBC, H2 yield rose by 32.4% compared to the control group without carbon material. Electrochemical analysis revealed MSBC improved the electrochemical properties of sludge. Furthermore, MSBC optimized the microbial community structure and increased the relative abundance of dominant microbes, thus promoting H2 production. This work provides a deep understanding of two carbons that play vital roles in increasing microbial biomass, supplementing trace element and favoring electron transfer in DF reactions. Salt recovery achieved 93.57% in molten salt carbonization, which has sustainability compared with N2-atmosphere pyrolysis.

Effect of Hydrostatic Pressure and Temperature on Extractability and Bioaccessibility of Lipophilic Micronutrients in Kale

High-pressure processing (HPP) represents a sustainable and gentle preservation technique. Since the effects of processing parameters are still poorly reported for lipophilic, bioactive ingredients (e.g., vitamin E and carotenoids), the present study covers a comprehensive set of HP applications using laboratory-, pilot-, and industrial-scale plants to evaluate nutritional aspects such as compound extractabilities, bioaccessibilities, and antioxidant capacities. Low-pressure regimes increased extractabilities of vitamin E in kale at 10 MPa (+105%) and at 50 MPa (+102%). Multicycle processing had no significant contribution to the extractability of target compounds. Thermally processed samples (40–80 °C) at 600 MPa retained major chlorophyll content in contrast to depletion after heat sterilization (121 °C). HPP improved the bioaccessibilities of vitamin E, lutein, and β-carotene even at 600 MPa (80 °C). Industrial-scale samples at high-pressure, low-temperature showed a more fresh-like texture elicited by a reduced need for sample comminution and optimal conditions for increased extractabilities of target compounds.

Industrial processes and the smart grid: overcoming the variability of renewables by using built-in process storage and intelligent control strategies

Manufacturers are facing pressure to reduce electricity costs. Onsite renewable energy generation may be a solution, but its high capital cost and intermittent power generation limit its use. Grid-responsive smart manufacturing could effectively incorporate renewables in industrial processes. This study integrates grid-responsive smart manufacturing with renewables on an industrial plant scale and demonstrates both a favourable economic and environmental outcome. A user-friendly decision-aid model for energy management is provided to manufacturers. A case study shows how solar panels, industrial batteries, smart pumping strategies, and various combinations of those elements can save on electricity costs. Dynamic simulation results demonstrate that grid-responsive smart manufacturing can effectively lower peak demand. The economic results show that grid-responsive smart manufacturing and renewables synergistically optimise cost reductions. The solar coupled with smart pumping scenario shows annual cost savings of $755,200, accounting for 4.6% of the total electricity cost. Smart pumping alone saves $371,900 annually with a 0.7-year payback period, demonstrating how the manufacturing sector can utilise its own processes in load shifting. This study supports that incorporating grid-responsive smart manufacturing with renewables can effectively reduce electricity costs and emissions for industry. Abbreviations: e: Equivalent; GHG: Greenhouse gas; PBP: Payback period; PV: Photovoltaics; SP: Setpoint; VFD: Variable speed drives

Three pathways towards elimination of CO2 emissions from industrial plants that use hydrocarbon fuels

Many industrial plants burn hydrocarbon fuels to generate electricity and high-temperature thermal energy required in their processes. This work proposes a novel system for generation of such thermal energy while eliminating CO2 emissions. The system produces electricity, thermal energy, methanol, and carbon black. Combined heat and power (CHP) unit generates high-temperature thermal energy and electricity required by the industrial plant; CO2 produced by CHP and by the plant itself is converted to methanol by using hydrogen produced via pyrolysis of methane, which has recently advanced to the first industrial scale plant. Thermal energy contained in the CHP flue gas replaces utility plant boilers or furnaces of the industrial plant (e.g. a refinery or a petrochemical plant). Two pathways are based on two different methane pyrolysis methods and CO2 removal via MEA absorption. The third pathway replaces MEA absorption with a novel in situ CO2 conversion reactor. Proposed pathways are examined as ways of eliminating CO2 emissions from a 5 million ton of crude oil per annum refinery. The study includes operational costs, capital costs, and material prices in USA, EU, and China. The results show that the proposed pathways are profitable for USA and EU, while for China they are not. The proposed pathways provide CO2 free energy generation from natural gas as an alternative to energy generation from either solar, wind or hydro energy sources. In addition, they enable capture and conversion of CO2 emissions from industrial process units.

Process modelling and optimisation of methane yield from palm oil mill effluent using response surface methodology and artificial neural network

Methane yield plays an important role in evaluating the performance of anaerobic digestion (AD) process due to fluctuating characteristics of palm oil mill effluent (POME). In this study, two years of industrial-scale plant data collected from biogas plant in Pahang, Malaysia consisting of methane yield and H2S concentration were modelled using supervised Machine Learning (ML) algorithms, i.e. artificial neural network (ANN) and response surface methodology (RSM). Input parameters appraised were pH, temperature, and recirculation ratio (RR) of total treated effluent and bottom sludge to raw POME. Fitness of all models was evaluated based on performance metrics, namely determination coefficient (R2) and root mean square error (RMSE). Results demonstrated that ANN was superior to RSM model with R2 of 0.9762 and 0.8500, respectively. Besides, three-dimensional (3-D) response surface plot was utilised to study interactive effects between AD parameters on methane yield. Temperature and recirculation ratio (RR) was found to be main interactive factor of methane yield which was corroborated using Pareto chart. Process optimisation using RSM revealed that the highest methane yield was 0.2733 N m3 CH4/kg CODremoved (i.e. improvement percentage of 9.3%) with the least H2S concentration of 1086.4 mg/L under optimum operating conditions, i.e. temperature, pH and RR of 42 °C, 7.36 and 2.5, respectively. Sensitivity analysis revealed that RR plays substantial roles in yielding more methane in AD process. Maintaining RR ratio at optimum level (1.05 to 2.60) is key to achieve high methane yield with good stability by considering the trade-off between operating cost and revenue of biogas plant.

Gasification of a typical low-rank coal in 65MWth KEDA® circulating fluidized-bed gasifier

The KEDA® circulating fluidized-bed (KEDA®CFB) gasifier is a high-temperature air-blown circulating fluidized bed developed by KEDA (ANHUI) Clean Energy Co., Ltd to produce clean industrial gas. This project describes the design and the initial operating results of using low-rank coal to produce industrial fuel gas in a 65MWth KEDA®CFB industrial-scale plant with a feeding rate of 13 ton/hr. The gasification process was carried out at an ambient pressure and temperatures at 980 ± 10 °C. A long-term stable operation was achieved for more than 20 days. Cold gas efficiency could reach 73% with a gas high heating value of 5.89MJ/Nm3 at a steam-to-coal ratio of 0.38 and an equivalence ratio of 0.3. During the stable operation, it was also observed that the operational bed temperature has to be kept under the residual ash fusion temperatures (AFTs) to avoid aggregation and defluidization.

Pilot-Plant-Scale Extraction of Antioxidant Compounds from Lavender: Experimental Data and Methodology for an Economic Assessment

The techno-economic feasibility of lavender essential oil supercritical CO2 extraction was studied. The process was scaled up to a pilot plant, and the extraction yield, composition, and antioxidant potential of the extracts were evaluated at 60 °C and 180 bar or 250 bar, achieving a maximum yield of 6.9% and a percentage inhibition of the extracts of more than 80%. These results drove the development of a business plan for three scenarios corresponding to different extraction volumes (20, 50, and 100 L) and annual production. The SWOT matrix showed that this is a promising business idea. The COM was calculated and an investment analysis was performed. The profitability of this process was demonstrated by means of a financial analysis for 8 years, considering a selling price of 1.38 EUR/g for the extract from the 20 L plant and 0.9 EUR/g for industrial-scale plants, supported by the price curve. The sensitivity analysis showed that the price of the equipment was the factor that could most influence the robustness of the project and the business strategy, and the financial ratios evaluation resulted in a ROE value above 57% in all cases, indicating the economic attractiveness of the process.

A FCM-clustered neuro-fuzzy model for estimating the methane fraction of biogas in an industrial-scale bio-digester

Real-time and offline monitoring, control and optimization of significant variables of bio-digester plants is crucial for optimal yield and maximum recovery of bioenergy at an industrial scale. Methane is an energy carrier and a critical component in the total biogas generated in a digestion process, thus necessitating more attention on the fraction of methane in the biogas yield. However, most previous studies in literature had focused on the volumetric yield of methane with little or no attention given to the fractional composition of methane in the total biogas produced. The deficiency of the classical technique in controlling the process parameters for optimal yield has motivated the need for machine learning-based techniques for modelling the methane fraction of biogas in a large-scale plant. In this study, a fuzzy c-mean (FCM)-clustered adaptive neuro-fuzzy inference system (ANFIS) was developed to model the methane fraction of biogas in an industrial-scale plant. The FCM clustering technique was preferred owing to its computational speed boost capability. The model was simulated using the control parameters of the algorithms while the optimal model was selected after testing their performance using relevant statistical metrics. The best model was obtained with ANFIS-FCM model with 8 clusters giving Root Mean Square Error (RMSE), Mean Absolute Deviation (MAD), Average Absolute Percentage Relative Error (AAPRE), Relative Mean Bias Error (rMBE) and correlation coefficient (R2) values of 3.156, 2.236, 3.015, 0.306, 0.978 respectively at the training phase and 4.936, 3.245, 3.456. 0.306, 0.956 respectively at the testing phase. The statistical metrics values obtained implied that FCM-ANFIS is a satisfactory model to predict methane fraction successfully.

Kinetic modelling and improvement of the ageing step of industrial alkylbenzene sulfonation process

The article describes the developed concept of a new, improved method of carrying out the alkylbenzene sulfonic acid (LABSA) ageing process in an industrial scale plant. Experimental studies of the new method of ageing step, confirming our expectations in terms of its high effectiveness, were preceded by the development of a mathematical model of the process, the high adequacy of which was verified in industrial realities.The improvement of the subject ageing step consists in replacing the conventional continuous process with a semi-batch one, carried out in a system of two swinging stirred tank reactors. In each of the swinging reactors, the reaction is performed in two stages: in the first stage, during the filling of the reactor tank, which runs under the continuous, unsteady regime, and in the second stage, starting to run after completing filling the reactor, undergoing in the batch process regime. In order to ensure entire plant throughput continuity, the work of both swinging reactors is time phase-shifted.The proposed solution was implemented on an industrial scale, within a real, licensed 24 000 t p.a. LABSA plant, achieving a 25–30% increase in the LAB to LABSA conversion rate. Above 98% of LABSA content and less than 0.3% of unreacted LAB were obtained in the final product, while maintaining a low value of the Klett colour index, not exceeding 20 units.Apart from the series of standard product quality indicators, particular attention was paid to the concentration of sulfones in the final product, the value of which did not increase in relation to the conventional process.

Engineering properties and microstructure of a sustainable roof tile manufactured with waste rice husk ash and ceramic sludge addition

Clay replacement with waste rice husk ash (RHA) and ceramic sludge (CS), helps to reduce the consumption of natural clay and solves the ecological issues created by waste disposal. In this study, properties of waste RHA and CS added fired clay tile were investigated, focusing on structural, durability, thermal performance as well as the water quality of the harvested run-off from fired clay roof tiles manufactured in an industrial scale plant. Tiles were cast by clay replacement with waste RHA and CS in four mixtures: 10 %RHA and 0 % CS, 10 % RHA and 10 % CS, 10 % RHA and 15 % CS, and 10 % RHA and 20 % CS (by weight). For 10 %RHA and 10 %CS tiles, dry mass was reduced by 4.9 %, compared with conventional roof tiles, promising a light weight roof tile. Roof tiles with 10 % RHA and 10 %CS showed a transverse breaking load of 1519 N, whereas that of 20 %CS tiles showed 1427 N, indicating that a further 6.5 % strength improvement can be achieved with clay replacement with a combination of two waste materials. Clay replacement with 10 % RHA and 10 % CS resulted in water absorption of 15.25 %. When increasing the clay replacement with combined waste from 10% (10 %RHA and 0%CS) to 30 % (10%RHA and 20 %CS), weight gain due to acid and alkaline attacks reduced from 3.5% to 3.0%, and from 2.2 % to 1.6 %, respectively, indicating enhanced durability performance by incorporating combined waste. High porosity, also confirmed by SEM, contributed to enhanced thermal performance: tile with 10 % RHA and 10 % CS achieved 4.4 °C temperature reduction, compared to the conventional tile. pH value and total solid concentration of run-off water were in the range of recommended values of water for agricultural purposes, ensuring that the collected run-off can be utilized as an alternative water source for potable activities.

Valorization of surface-water RO brines via Assisted-Reverse Electrodialysis for minerals recovery: Performance analysis and scale-up perspectives

Reverse osmosis (RO) processes have been recently identified as mostly capable of quantitative removal of salts and contaminants from saline and surface waters, though posing the problem of a concentrated brine to be disposed of and a produced permeate too low in minerals, thus requiring a sometimes expensive remineralization step. In the present paper, Assisted-Reverse Electrodialysis (A-RED) has been proposed for the remineralization of surface-water RO permeate by recovering minerals from its brine. A purposely developed and validated model has been adopted to carry out a parametric analysis for design and optimization of an industrial-scale plant. The techno-economic analysis underlined that full permeate remineralization can be achieved with minimum specific energy consumption of 0.08 kWh m−3, while a minimum remineralization cost of 2.2 c€ m−3 was found applying a permeate by-pass and feed & bleed scheme to (i) increase the plant remineralization capacity and (ii) maintain a stack inlet conductivity above 100–160 μS cm−1 (starting from a permeate ~10 μS cm−1). Compared to current post-treatment techniques, results appear very promising thanks to the reduction of chemicals and total costs as well as environmental concerns related to brine disposal.

Characteristics of the Combined Rolling and Extrusion Process

The combination of the conventional forming processes rolling and extruding enables the continuous production of cross-sectional aluminum long products. Regarding power consumption and resulting material specifications, the combined process offers various advantages in comparison to its conventional alternatives [1, 2]. The combined rolling and extrusion process is in an early stage of maturity. The production of pure aluminum wire is state of the art. The material flow within the process can partially reproduced by the use of numerical simulations [3]. Some process specific characteristics need to be understood and controlled to obtain a better process design and to enable the future production of complex cross-sectional products. This paper describes the results of experimental and numerical investigations regarding the combined rolling and extrusion process. The test specimen of a visioplastic examination on an industrial scale plant [3] was examined by the use of metallography. Those results where compared to a numerical simulation of the industrial experiment. The comparison of these results where then linked to some specific characteristics of the process. The existence of a dead zone with a shape comparable to the conventional indirect extrusion process was proved. The deformation zone of the combined process was divided into four zones which can be differentiated in the experimental as well as the numerical results. General design rules were derived from this differentiation. These design rules were used to optimize the forming geometry of an industrial scale plant. Critical process forces where reduces and resulting scrap material was minimized.

Science and Business Developments

Science and Business Developments

70 Years of LD-Steelmaking—Quo Vadis?

Basic Oxygen Furnace (BOF) steelmaking is, worldwide, the most frequently applied process. According to the world steel organization statistical report, 2021, it saw a total production share of 73.2%, or 1371.2 million tons per year of the world steel production in 2020. The rest is produced in Electric Arc Furnace (EAF)-based steel mills (26.3%), and only a very few open-hearth and induction furnace-based steel mills. The BOF technology remains the leading technology applied based on its undoubted advantages in productivity and liquid steel composition control. The BOF technology started as the LD process 70 years ago, with the first heat applied in November 1952 in a steel mill in Linz, Austria. The name LD was formed from the first letters of the two sites with the first industrial scale plants, Linz and Donawitz, both in Austria. The history and development of the process have been honored in multiple anniversary publications over the last few decades. Nevertheless, the focus of the steel industry worldwide is significantly changing following a social and political trend and the requirement for fossil-free energy generation and industrial production to be in accordance with the world climate targets committed to in relation to the decades leading up to 2050. Iron and steel production is one of the major polluters of climate changing greenhouse gases; it must change to renewable primary energy sources and the use of climate-neutral reduction agents. Because it is very obvious that carbon, as the main component for steel strength properties, cannot be eliminated totally from the steel production process, the question arises of where a “zero carbon” approach can lead? This paper will review the ongoing success story of the LD-process, discuss the recent technology advancements, and give an outlook on the future role of the process in the steel industry.