Palm Oil Mill: Just Replacing Boiler? Or Are You Also Looking for a Solution to Address the Problem of Empty Fruit Bunches and Generate Additional Profits?

As palm oil plantations in Indonesia continue to expand—currently covering approximately 17 million hectares—the demand for palm oil mills is also increasing. About 10 years ago, there were approximately 1,000 palm oil mills in Indonesia, but according to the latest data from the Ministry of Agriculture of the Republic of Indonesia, the number of active palm oil mills (POM) in the country is now estimated to be between 1,200 and 1,500. These palm oil mills are primarily located on Indonesia’s two largest islands: Sumatra (52.69%) and Kalimantan (42.71%), while the remainder are in Sulawesi, Papua, and several other islands, where their presence is relatively small (each accounting for less than 3%). In terms of ownership, the majority of palm oil mills in Indonesia are owned by large private companies (93%), with the remainder owned by state-owned enterprises (7%). A single large private company may own a dozen or even dozens of these palm oil mills. 

One of the main equipments for palm oil mill operations is the boiler. In fact, given the current palm oil mill production process, boilers are mandatory for palm oil mills; more details on the reasons can be found here. Boilers can also be considered the "heart" of a palm oil mill, converting water into high-pressure steam to run the production process and generate electricity for the mill and its employee housing. Like all production equipment, boilers have a lifespan. When a boiler's lifespan is exceeded, it becomes not only uneconomical due to high maintenance and operational costs, but also dangerous.

The average lifespan, which is the technical and economic life of a palm oil mill boiler, is 20 years. Once this lifespan is exceeded, investing in a new boiler becomes more profitable. The majority of palm oil mills in Indonesia use water tube boilers (e.g., Takuma or Vickers). This type of boiler circulates water through hundreds of externally heated pipes fueled by palm oil waste in the form of shells and fibers. Because these pipes interact directly with extreme heat and water scale, these internal components wear out most rapidly. The three main factors affecting the boiler's lifespan are boiler feedwater quality, fuel characteristics, and regular maintenance.

When the time comes to replace the boiler, and considering the mountains of unused empty fruit bunches (EFB), palm oil mills might consider using them as boiler fuel. But given their large size and high moisture content (>60%), how can they do that? This is certainly a reasonable and innovative idea, given the urgency of replacing the boiler and simultaneously facing the problem of biomass waste. Technically, as biomass waste, it can certainly be used, but is it economically feasible to treat or prepare the empty fruit bunches (EfB) until they are ready for use as fuel? This is the challenge.

Proven evidence will dispel any doubts or theoretical narratives. Likewise, a unit that can process empty fruit bunches (EFBs) and also serve as an additional energy source for boiler operations (cogeneration) at the palm oil mill. With this equipment, not only can the problem of empty fruit bunch (EFB) biomass waste be resolved, but the palm kernel shells (PKS), which have been used as boiler fuel along with the fiber, can be 100% sold directly, providing a source of income. Furthermore, the potassium-rich ash content of empty fruit bunches (up to 30%) also has the potential to be used as fertilizer, including for use on the palm oil plantation. For more details, please read here. Visiting and observing the unit in action can also serve as a means of proving the point, thereby increasing the confidence of palm oil mills interested in this solution.

Beyond technical factors, economic considerations will undoubtedly be a crucial consideration in implementing this equipment. By considering several factors, particularly those currently operating in the palm oil industry, a comprehensive and accurate economic analysis can be conducted to reach a decision on use of the equipment. In an era of renewable fuels, efficiency, zero waste, and increased profitability, this equipment, which serves as a supplemental energy source (cogeneration) for the palm oil mill's boiler, is worth considering for palm oil mills currently facing boiler replacement. 

Maximizing Palm Oil Mill Profits with Cogeneration Utilization of EFB (Empty Fruit Bunch) and Export of PKS (Palm Kernel Shells)

As a profit-oriented company, maximizing profits is a natural and ongoing endeavor. Besides increasing efficiency, innovation can also be pursued, creating or developing new businesses. This is especially true if the innovations involved in creating new businesses also address environmental issues, such as utilizing palm oil mill biomass waste. In palm oil mills, empty fruit bunch (EFB) waste is generally underutilized, or if utilized, it is still suboptimal or inadequate, such as composting empty fruit bunches (EFB).

Empty fruit bunches (EFB) are a significant biomass waste product from palm oil mills, accounting for approximately 22% of the total production, but are generally underutilized and pollute the environment. Utilizing EFB through cogeneration will not only address the problem of EFB, but also generate heat or energy to replace the use of palm kernel shells (PKS) as boiler fuel, and also produce high-quality organic potassium ash fertilizer.

If the PKS used for boiler fuel reaches 50%, then using this technology means that 50% of the PKS can be recovered, or 100% of the PKS can be sold or exported. For example, a palm oil mill normally sells 3,000 tons of PKS per month. With this technology, the mill can sell 6,000 tons of PKS per month. This would certainly increase the supply of PKS significantly.

Even if applied on a larger/macro scale, namely in Indonesia with CPO production of around 50 million tons/year, the actual production of PKS is around 12.5 million tons/year. However, with the current practice of utilizing PKS as boiler fuel, say reaching 50% of PKS production, the actual amount of PKS that can be sold/exported by palm oil mills is 6.25 million tons/year. Now, with the use of this technology or the installation of equipment (EFB furnace cogeneration), the amount of PKS that can be sold/exported will be close to or equal to the PKS production in the mass balance or diagram above (not subtracting the amount burned in the palm oil mill boiler).

The demand for palm kernel shells (PKS) is increasing in line with the global decarbonization trend. In fact, PKS is a major competitor for wood pellets in the global biomass fuel market. Large PKS users come from Japan and Europe. PKS exports to Japan typically reach around 10,000 tons per shipment, while those to Europe typically reach a minimum of 30,000 tons per shipment due to the longer distances and the use of handymax or even panamax vessels. Cogeneration of empty fruit bunch (EFB) furnaces with palm oil mill boilers will increase the volume of PKS that can be sold or exported. Implementing this technological innovation, besides being the fastest and most practical, also offers multiple benefits, making it worthy of consideration. It could even become a trend and even a standard operating procedure in Indonesia's approximately 1,000 palm oil mills.

Processing of Empty Palm Fruit Bunches (EFB) for Ash Production as Potassium Fertilizer and Energy

Palm oil mills produce a large amount of biomass waste, and one of the largest in their daily operations is empty fruit bunches (EFB). Comprising approximately 22% of the fresh fruit bunches (FFB) processed by the mill, the volume becomes enormous and piles up daily if not managed properly. For example, a palm oil mill with a capacity of processing 60 tons of FFB per hour for 20 hours per day produces 264 tons of empty fruit bunch waste per day (approximately 6,600 tons per month and 79,200 tons per year). This enormous amount would resemble a hill if piled up in one place.

Incinerators have recently become popular, particularly in Indonesia, for processing empty fruit bunches due to their speed and practicality. Furthermore, the ash produced by burning them can be used as fertilizer due to their high potassium content. However, these incinerators produce exhaust emissions that pollute the environment, including black smoke and particulate matter. These emissions, which pollute the environment and exceed the threshold permitted by the Ministry of Environment (KLH), have led to the prohibition of incinerators. This ban has led to an increasing number of unmanaged empty fruit bunches. Using empty fruit bunches for mulch is also less effective, and composting, a biological process, takes a long time.

Video link for conventional EFB incinerator here

This problem demands an immediate and effective solution. The quickest practical solution is to upgrade the incinerator to make it environmentally friendly or to reduce emissions below the required threshold. This can be achieved by using adequate emission control devices to meet these environmental requirements. While many emission control devices are available, cost and target output are crucial considerations when selecting them. This approach not only addresses the problem of empty fruit bunches, but the resulting ash can also be used as a potassium fertilizer.

Furthermore, by upgrading the incinerator with emission controls (basic type), the equipment can be developed into several types, as follows: the second type is a cogeneration boiler for palm oil mills, allowing 100% palm kernel shell (PKS) to be sold, even for export. The third type is by adding a new boiler and steam turbine for electricity production, which is then sold to PLN (Indonesia State Owned Electricity Company) under a power purchase agreement (PPA). The fourth type is equipped with waste heat recovery equipment, allowing for more general use. This also means the combustion process in the upgraded incinerator can also be upgraded so that the combustion process can run optimally. Several combustion technologies, such as chain grates, step grates, or reciprocating grates, can be considered to achieve maximum performance, including the removal and handling of ash product.

Empty fruit bunches (EFB) processing can vary, although the primary focus is addressing environmental pollution caused by them. However, their large volumes certainly represent a potential raw material for processing units. Therefore, in addition to addressing this waste, the technology used must also provide financial benefits. Of the numerous EFB processing technology options, the cost-to-benefit ratio of a technology application will be a crucial consideration for EFB processing.

In addition to combustion using conventional or this upgraded incinerator, thermal processing routes also include pyrolysis, with slow pyrolysis specifically for biochar production and fast pyrolysis for bio-oil production. Another pyrolysis variant is mild pyrolysis or torrefaction for the production of torrified biomass. Then there's gasification to maximize gas (syngas) production from biomass. Furthermore, empty fruit bunches of palm oil can be used as fuel or an energy source. To facilitate handling, storage, and reduce transportation costs, empty fruit bunches need to undergo biomass densification technology, with the final product being pellets or briquettes.