Whether it is the South African government’s newly signed carbon tax legislation or the EU’s ‘green’ import taxes, South Africa’s manufacturing sector faces significant challenges. These challenges are centered around sustainability and adapting to new environmental regulations.

As the debate around emissions, affordability, and ‘green’ taxes on exports to the EU intensifies, uncertainties remain. It is unclear how emissions will be measured or if improvements to existing energy plants will be recognised by authorities.

Manufacturing companies may also face pressure to completely switch to alternative fuels. This would be a significant challenge for South African manufacturers that still depend on fossil fuels.

Solid debate around energy efficiencies

We believe a company’s sustainability journey begins by maximising what can be achieved with existing energy plants. By managing combustion effectively and ensuring it responds to changing manufacturing needs, both costs and emissions can be optimised.

However, different fuel types react differently to fluctuating steam demands. For example, as gas combustion systems provide a high range of turndown, they respond extremely quickly. Solid fuel combustion systems such as coal and biomass react more slowly to changes in steam demand.

There is always a set amount of solid fuel in the combustion furnace at any given time. Any changes in steam demand will require adjustments to the amount of fuel being fed into the furnace. The amount of oxygen must also be adjusted to maintain effective combustion.

The problem arises where there are multiple boilers online and suddenly, there is a substantial steam demand peak. On regular auto-control, they ramp up to follow that peak and eventually catch up. However, when it subsides, there is a massive amount of thermal inertia in these boilers. It is very difficult to quickly counteract this, and this is wasteful in terms of one’s ability to burn coal effectively.

Balancing the load

A load balancing system enables multiple solid-fuel boilers to work together to effectively and efficiently deliver steam on demand. Key to this is understanding a company’s steam load. If it is flat with only gradual changes, loads can easily be followed. Sudden spikes and drops in steam demand are unfortunately more difficult to control.

A co-ordinated approach, using the overarching load-balancing control system, effectively coordinates steam demand across the multiple boilers and ensures optimisation of the online capacity to deliver the demand efficiently and effectively.

Each of those boilers must be controlled to synchronise to follow the load – and reduce when the load reduces. This system achieves optimised efficiency and improves the assets’ ability to maintain pressure control by applying analysis to demand changes to sequence boiler loads effectively.

The era of ‘smart’, data-driven steam

These systems are very much data driven. Setpoint inputs are carefully adjusted to ensure the narrowest steam pressure control band possible is achieved, so that steam pressure remains stable. The key metrics within the operating model should be adjustable to meet the unique requirements of each site – and accommodate the number of boilers that need to be load-balanced.

Furthermore, instrumentation really comes to the fore in measuring the efficiency of combustion based on the constituents of the flue gas coming out of the boiler. We rely on levels of carbon dioxide and oxygen to tell us if we have too much or too little fuel or oxygen to achieve the right reaction. That is all data-driven.

The remote monitoring system (RMS) should work hand-in-hand with its load-balancing module. The two share some instrumentation and data streams. Through the RMS, clients can see what is happening from an operational perspective.

Variable speed drives (VSDs) provide more accurate control of elements like the boiler stoker and fans than before. Data is widely used to manage these systems on an ongoing basis. However, human intervention remains important for optimal performance.

You still need someone with an acute understanding of what you are trying to achieve to set up the system. An element of intervention and oversight by skilled and experienced operations and maintenance personnel in certain circumstances is still needed. An example is having the knowledge to ensure the correct bed depth on the stoker, which other automated systems have failed to do successfully.

A better balanced future

The benefits of load-balancing include improved control over combustion processes and steam quality. It also leads to reduced fuel consumption and, ultimately, lower carbon and green taxes. Looking ahead, businesses will need to collaborate more closely to meet sustainability targets. They must also enhance efficiency and minimise costs.

As green taxes become more prevalent, the need for accurate monitoring and effective load-balancing will increase. Data-driven insights that enable these processes will become even more important.

Dennis Williams | Commercial Director | Associated Energy Services (AES) | mail me |

Related FAQs: Green manufacturing load-balancing

Q: What is green manufacturing load-balancing?

A: Green manufacturing load-balancing refers to the practice of distributing manufacturing processes and energy consumption in a way that optimises the use of sustainable energy sources, thereby reducing environmental impact and improving overall efficiency.

Q: How does automation contribute to sustainability in manufacturing?

A: Automation enhances sustainability by streamlining manufacturing operations, reducing waste and optimising energy consumption. This leads to more efficient production processes and helps companies achieve sustainability targets.

Q: What role do renewable energy sources play in green manufacturing?

A: Renewable energy sources are essential for green manufacturing as they provide cleaner alternatives to traditional energy sources, helping industries reduce their carbon footprint and reliance on fossil fuels.

Q: How can small and medium-sized enterprises (SMEs) implement green manufacturing practices?

A: SMEs can implement green manufacturing practices by adopting automation technologies, utilising renewable energy sources, optimising their production lines, and focusing on sustainable development to reduce their environmental impact.

Q: What are the benefits of achieving sustainability in the manufacturing industry?

A: Achieving sustainability in the manufacturing industry leads to reduced operational costs, improved brand reputation, compliance with environmental regulations and the ability to attract environmentally conscious consumers.

Q: Can simulation tools help in optimising manufacturing operations for sustainability?

A: Yes, simulation tools can help optimise manufacturing operations by providing real-time data analysis, allowing companies to assess different scenarios and identifying the most energy-efficient production processes.

Q: What strategies can companies use to meet their sustainability targets?

A: Companies can meet their sustainability targets by investing in renewable energy sources, enhancing automation in their manufacturing processes, conducting case studies to benchmark best practices, and focusing on reducing energy demand across their operations.

Q: How does the manufacturing industry benefit from industry 4.0 technologies in terms of sustainability?

A: Industry 4.0 technologies enhance sustainability by enabling real-time monitoring of energy consumption, improving automation in manufacturing processes and facilitating data-driven decision-making to minimise environmental impact.

Q: What challenges do manufacturing enterprises face in transitioning to sustainable practices?

A: Challenges include the initial costs of implementing renewable energy solutions, the need for staff training on new technologies and potential disruptions during the transition period. However, the long-term benefits often outweigh these short-term challenges.