ISSCT Joint Engineering and Processing Workshop

Theme: Innovations in the Sugar Cane Industry – Enhancing Sustainability, Quality and Efficiency

The ISSCT workshop, held in Berlin from 6–10 October, attracted 120 delegates from 20 countries. Due to visa issues, some were not able to attend. Nonetheless, the event was the largest in terms of delegate numbers, supported by 17 companies that sponsored it by showcasing their products and services at their stalls. Their support was crucial to the event’s success. On the fourth day, Nordzucker hosted a visit to their beet sugar factory, Klein Wanzleben. Participants of the Workshop in Berlin

This was the third time an ISSCT engineering workshop was held in Berlin. I attended the second one held in 2001 and vividly remember the event’s Chair Pedro Avram’s regimental control of presentations with a 3-minute bell. The mantle has been passed on to Boris Morgenroth, IPRO, who managed the event ably and was supported by session chairs. The event attracted industry heavy weights (Prof Gillian Eggleston, Audubon Sugar Institute, Steve Davis, SMRI, Darryn Rackemann, QUT, and Narendra Mohan, former Director of NSI), and talented young engineers and researchers. In total 50 presentations were given over three days in Hotel Melía, in the heart of the city.

The overarching themes of the workshop included Industry 4.0, sustainability, particularly regarding energy economy and green cane harvesting, various online measuring devices deployed in the industry, and sugar quality.

Plenary: The plenary included an insightful presentation on how the application of biochar (from low temperature pyrolysis of bagasse/trash) can be utilised as a soil ameliorate to provide significant beneficial impacts on soil health, improved cane yields, and reduced GHGs compared to traditional fertilisers. While biochar has long been touted to provide valuable benefits to the agricultural sector, the plenary outlined the circular nature and measurable impacts that can be defined with improved knowledge and scientific rigour. While limited cost data was presented, it was noted that in the US, with significant government incentives, biochar applications were becoming more economically attractive. “Carbon credits” or sustainability metrics are expected to help accelerate adoption.

Lima (presented by Eggleston) – Circular Sustainability of the Sugar Crop Processing Industry through By-Product Utilization

Auditorium during the lectures at the Hotel Meliá Berlin

Industry 4.0: Factories in South Africa and Brazil shared their experiences on the journey to Industry 4.0, paving the way for improving plant efficiency and reducing cost. The first stage was built on digitalisation and the importance of reliable sensors and accessible data (connectivity, wifi) and presented in simple, concise and compact dashboards (with possible guidance suggestions) for decision makers (operators, supervisors) to make quick and informed process control changes. Future stages of Industry 4.0 development will likely include more advanced, fuzzy logic predictive process controls. Rainer Talanda, Illovo Sugar Ltd., South Africa

An example of a factory digital twin system (Brazil) based on underlying mass and energy balance flowsheets was also presented. This system allows strategic decision making and potential operator training. Bernd Langhans (Siemens) stressed the need to fully embrace historical records when developing the system. Steve Davis (SMRI) pointed out that it should also benchmark top-performing factories to support a progressive insight. There were different opinions on whether industry 4.0 and digitalisation delivers return on investment or improves operations and reduces staffing. The general consensus was it was more appropriate for greenfield sites.

Talanda – Industry 4.0 Digitation – Leading factory KPI dashboards

Dare – Online management assisted by digital twin

Energy Management: A number of presentations were given providing updates on energy management practices and studies undertaken recently to provide incremental advances focused on cogeneration, evaporation and crystallisation implementation of best practices in sugar factories. This highlighted the existing state of our knowledge and there was some discussion on the possible future prospects for the industry. Boris Morgenroth, IPRO GmbH, Germany

Mann – Cogeneration in sugarcane factories – past, present and future

Morgenroth – Power export potentials in the cane sugar industry

Green Cane Harvesting: South African, Australian and Colombian perspectives of green cane harvesting were presented. The impact of co-processing of trash on factory performance was reported (lower recovery, increased bagasse moisture, increased colour formation, higher ash, starch and reducing sugars contents). Best practice harvesting guidelines are readily known (published) but not necessarily adopted due to limited incentives incorporated into payment systems, and economics still dictate high pour rates of harvesters. Green cane harvesting results in lower pour rates, which are informed by increased costs from post-harvest cleaning. Results of small scale in-field and at-factory post-harvest cleaning were also presented and showed extra losses could be caused by billet damage in the separation system, but good design can mitigate and improve the feeding and shredding systems that typically cause issues at the factory.

Talanda – Insights on green cane

Gomez – From harvest to milling: Standardization of trash evaluation and an approach to its impacts

Sustainable processing practices (included mass and energy balances): The session included updates on state of the art technologies: vertical continuous evaporating crystallizers (cleaning practices), platular heat exchangers and mechanical vapor recompressors (MVR), which can be cost effective in certain situations, discussion on jet versus barometric condensers, as well as the impact of chemicals/additives on achieving efficiency and energy-saving gains when dealing with increased impurity loadings (such as with increased levels of green cane harvesting). Preliminary results of small-scale pilot trials were also presented for a juice softening technology (filtration and ion exchange) with low chemical usage (no evaporation or crystallisation tested). The technology is well utilised in the beet industry but has yet to see any adoption in the cane industry due to the different composition of cane juices. When linked with diversion strategies, it appears to have more benefit.

A good theoretical presentation by Thaval compared the performance of falling film (FFE) and Robert evaporator stations, which included a conceptual 7-effect FFE station (and one option with MVR). Comparison of steam/vapour pressures, steam consumption on cane, residence time and sugar losses by hydrolysis, power consumption, and costs. This was followed by two presentations on the Bindal sugar factory (ISGEC) that implemented a 7-effect evaporator station (a cane industry first) with other steam efficiency options adopted (achieving 25.5–30 kg steam/100 kg cane) and with B molasses directed to ethanol production. The factory design included a B massecuite 41 m high vertical continuous evaporating crystallizer with 5 modules with vapours directed to an inline juice heater, and the plan was to implement a C massecuite processing station to address Indian government pricing constraints. Discussion was held around the unique Indian situation where the price of ethanol is set based on a demand and supply balance to stabilise ex-mill prices of sugar and depends on the feedstock, whether it be corn, A, B or C molasses, cane juice or syrup etc. Factory designs incorporating flexibility for changing the diversion of sugar streams based on an economic potential raise the question of sugar house equipment utilisation.

The discussion noted that steam consumption should be taken in the context of also knowing amount of juice and massecuite on cane for comparison purposes, as some Indian papers usually report steam consumption based on return condensate (92–97% of process steam).

Lehnberger – Vertical continuous vacuum pans for high & low grade massecuites in cane sugar factories

Salgue – Cane juice softening through ion exchange: unveiling a sustainable and cost-effective approach

Sugar Quality: Colour and polysaccharides (particularly regarding green cane harvesting) were the key components influencing sugar quality that formed the base of discussions in these sessions. The origins and theories of colour development and transfer were discussed, confirming that cane plants (and dextran content) and temperature/pH (process) are the key parameters contributing to sugar colour and development. Models for colour development during storage based on temperature, ash and reducing sugar content were reported. Insoluble starch is often not adequately measured using existing methods and was found to significantly contribute to low sugar exhaustion from molasses in the US. New analytical methods were represented. Additionally, a more heat-stable amylase showed promising results in laboratory tests but is not widely commercially available. Additionally, a detailed process model was developed to examine the impact of evaporator sizing, how vessel rearrangement can minimise sucrose losses by optimising performance, and the use of online heat transfer coefficient monitoring to influence cleaning schedules.

Renderos – Estimation model for color increase in refined sugar

Gabriel – Process analysis in evaporation stations: Comprehensive approach to improve performance and reduce sucrose losses

NIRS / instrument technology applications; and Factory data analyses and trends: NIR systems, already widely adopted in some countries for cane payment alongside traditional analyses, are being further developed for various applications. In South Africa, NIR is replacing conventional analytical methods, offering cost savings and reducing chemical usage, though change management and building confidence in the technology remain key challenges. Elsewhere, NIR is being used to monitor trash, extraneous matter (EM), and soil in the US, while Australia is exploring its potential for detecting impurities such as polysaccharides in cane. In Reunion, it is being applied to sugar quality parameters like color, moisture, and crystal variation.

Several presentations, such as NIRS progress within Illovo Sugar and Implementing Near-Infrared Spectroscopy for quantifying trash/extraneous matter in the Louisiana cane payment system, emphasized NIR’s role in optimizing sugar production processes through real-time and online analysis. Trials aimed at automating and refining systems for analyzing sugar content of juice, monitoring rds, and assessing ash, turbidity, and filterability were also reported. Advanced technologies such as inline transmission for rds monitoring, microscope cameras for crystallization control, and valve monitoring systems were explored to enhance production efficiency. Additionally, papers addressing sugar quality, including Color transfer into sucrose crystals and influence of dextran on color inclusion, underscored the importance of managing impurities like starch and dextran to improve overall product quality and meet market demands. These advancements demonstrate the industry’s commitment to high-throughput, accurate measurement systems and enhanced production efficiency.

Raghunandan – NIRS progress made in Illovo

Zhao – Optimisation of process Brix monitoring during evaporation by advanced inline transmission technology

Material Handling: A couple of presentations on (i) the benefits of stress minimization in centrifuge baskets from elliptical slots versus traditional holes and other modifications to improve safety; (ii) benefits (greater surface area) and practical aspects (currently limited to 1.4 m length) of honeycomb calandrias for crystallizers as well as other key aspects of evaporating crystallizer design to improve productivity; and (iii) the use of waste process heat (hot water or steam) in bagasse dryers and design considerations and learnings over the last 5 years.

Spangenberg – Centrifugal safety by design: State of the art

Kimmenauer – Experiences with low-temperature dryers in the cane sugar industry

Other – Beet and Cane: Eggleston presented the whole of chain proposition of key crops, sugarcane, beet, and sweet sorghum, and how their key compositional differences can be leveraged to develop more sustainable practices. Other crops (tropical beet) could offer the potential for new products and increased capital equipment utilisation in factories, similar to that shown at the Almoiz factory (Pakistan), processing cane and beet in separate campaigns and also operating a refinery campaign.

Eggleston – Sugarcane & sugar beet processing: Similarities & differences to underpin sustainable practices

Avram-Waganoff – Updated technology transfer possibilities between beet and cane sugar production

Field trip – 10th October 2024

Visit to Klein Wanzleben beet sugar factory (Nordzucker AG, located 130 km west of Berlin). The factory was erected in 1994 as part of the sugar industry’s reorganization after German reunification. The factory slices nearly 15,000 t/d of beet.

In 2007, the factory commenced operation of a bioethanol facility, using beet raw juice and beet thick juice as feedstocks.

Visit to Klein Wanzleben beet sugar factory

It operates, among other things, a thick juice storage, two tower extractors, a six-effect falling film evaporator station, and three BMA VKTs. It produces only white sugar according to the EU quality standards. At the time of construction, it operated a vapor recompression plant. Currently, investments are being made to reduce the CO₂ emissions by 50% in 2030, based on the average for the years 2017–2019.

Prize Winners

At the end of the Workshop, young engineers and researchers were recognised for their input. The following were commended:

Engineering Section: Guilherme Fraga, from São Martinho

Process Section: Rafael Renderos, Compañía Azucarera Salvadoreña

Early Career Scientist Award: Stephania Imbachi-Ordonez, Audubon Sugar Institute

Acknowledgements

Darryn Rackemann wrote the bulk of the review, with input from Stephania Imbachi-Ordonez and Mohan Patil (Dinamic Oil).

Attendees in Klein Wanzleben

See also: Photo Gallery