Palm oil is a paradox.
It’s a vital ingredient in countless products, from food to cosmetics, and a crucial economic driver for many nations.
The global demand for vegetable oils – including palm oil – is soaring, with production of vegetable oils forecast to reach 222.8 million tonnes by the end of 2024.
Although palm oil is the most efficient vegetable oil, its production has been linked directly and indirectly to deforestation, human right abuses and climate change.
At the heart of the palm oil industry lies a complex value chain, from plantations to processing facilities and refineries. Each stage in this chain presents opportunities for both environmental harm and positive impacts.
For example, the conversion of palm oil waste products into biofuels, bioproducts or biofertilisers offers a pathway to reduce the industry’s carbon footprint. However, the expansion of oil palm plantations into forested areas remains a major concern.
As the largest vegetable oil industry in the world, it’s critical palm oil decarbonises its value chain to support the global transition to sustainability.
In the last decade, various initiatives and certification systems, such as the Roundtable on Sustainable Palm Oil, Malaysia Sustainable Palm Oil and Indonesia Sustainable Palm Oil have been developed to promote sustainable production.
These certifications are aimed at auditing current practices and promoting sustainable production methods.
The path to palm oil
Palm oil production involves several steps.
First, palm fruits are harvested from oil palm plantations. These fruits are then processed in mills to extract the crude oils (crude palm oil and crude palm kernel oil). During the extraction of crude oils, this process creates waste or by-products such as empty fruit bunches and palm kernels.
These by-products can be reused in various ways such as being turned into biofertiliser, fuel or electricity. However, this process isn’t always efficient and can still harm the environment if not managed with proper treatment and disposal.
Additionally, growing and processing palm oil requires resources such as water, energy and chemicals. Waste from palm oil mills, if not properly managed, can pollute water sources and the mills also release a significant amount of greenhouse gases. Deforestation to make way for new palm oil plantations also contributes to climate change.
To address these issues, researchers are exploring ways to make palm oil production more sustainable, such as conversion of by-products into biofuels and biomaterials capturing and using the greenhouse gases produced, and using less harmful chemicals.
Decarbonisation strategies
Various efforts to decarbonise the palm oil value chain have been tried. These include both nature-based solutions and engineered solutions.
Nature-based solutions aim to restore carbon dioxide via the natural photosynthesis process as natural carbon sinks, which absorb more carbon than they release, while engineered solutions attempt to capture greenhouse gas emissions for storage and later use.
Based on current practices, by-products generated as part of the plantation and milling processes, in the form of oil palm fronds and empty fruit bunches, are returned to the plantations for mulching to return nutrients to the soil.
To enhance nutrient recovery from the empty fruit bunches, they can be converted into biofertiliser via fermentation. The produced biofertiliser has a higher nutrient content and is more easily absorbed by the tree. It also reduces the time the by-products take to degrade.
Palm kernel shells can be converted into biochar, a form of plant matter like charcoal which locks the carbon they contain away rather than releasing it if the shells were to naturally decompose.
This biochar gets returned to plantations and is considered a negative carbon emission. At the same time, it also improves the microbial activity in the soil.
Using by-products from palm oil production
To use the carbon dioxide captured from palm oil processing facilities, technologies can convert it into useful products such as biofuels, biochemicals or construction materials.
However, these technologies are complex and costly, so they are not widely used in the sector.
Instead, most efforts focus on converting palm-based by-products into valuable products and extracting biogas from palm oil mill effluent or wastewater generated from palm oil milling activities. This helps reduce carbon and greenhouse gas emissions from the process.
Anaerobic – in the absence of oxygen – digestion of the palm oil mill effluent in covered lagoons or tanks turns organic materials into biogas, which is mainly methane (approximately 60 per cent). This biogas can be purified into biomethane (approximately 92 per cent of methane) and used as fuel or supplied to the national gas pipeline.
Other palm-based by-products, such as palm kernel shells and mesocarp fibre, are used as a biomass fuel to generate steam and electricity in combined heat and power systems, for processing facilities.
Empty fruit bunches can also be turned into pellets, briquettes and dried long fibre, which are used as a feedstock or energy source. Dried long fibre is also used in mattress manufacturing, while briquettes and pellets are used in power plants to reduce fossil fuel consumption and cut carbon emissions.
Biodiesel, which is derived from crude palm oil, can replace fossil fuel-derived diesel. Trucks can also be modified to run on biomethane instead of diesel.
These efforts can help reduce the carbon footprint of the palm oil industry.
However, the use of these technologies is limited due to price fluctuations, low-efficiency biomass conversion technologies for biofuel production and the need for highly skilled personnel to operate the biomass conversion system.
The role of chemical engineers
Given the complexity of the palm oil value chain, it is crucial to develop strategies and action plans tailored to specific geographical, economic, environmental, political and cultural constraints to help the industry decarbonise further.
Here, chemical engineers play a key role in the decarbonisation journey. As well as the strategies outlined above they can also promote material and energy recovery and exchange with multiple industries, and expand the use of palm-based by-products in other sectors to encourage the adoption of a circular economy framework.
Chemical engineers can develop new technologies to improve oil extraction and reduce energy consumption, especially since many processing facilities are outdated.
They can optimise transportation modes, fuel types and routes to create a sustainable supply chain. This includes using energy-efficient vehicles, alternative fuels and exploring low-carbon options such as rail or waterways.
Finally, they can use advanced artificial intelligence to design better processes and products, implement novel systems in palm oil processing facilities and develop sustainable products to meet growing global demand.
By combining circular economy principles with decarbonisation strategies, the palm oil industry can reduce its carbon footprint and contribute to climate change mitigation.
Chemical engineers play a pivotal role thanks to their expertise in process design and optimisation. They are essential in transforming the industry and achieving net zero targets.
Originally published under Creative Commons by 360info™.