Biomass Boiler Testing and Selection of Suitable Biomass Fuel

In line with the trends toward decarbonization and sustainability across various sectors of life, particularly in the processing industries (manufacturing/process industries), the use of biomass boilers has become a realistic option today among boilers that utilize other renewable energy sources. Fossil-fuel-fired boilers—such as solid-fuel boilers (coal), liquid-fuel boilers (industrial diesel), and gas-fired boilers (natural gas)—must be replaced with renewable fuel boilers, namely biomass boilers. Apart from technical factors in the form of operational adjustments from previous fossil-based fuels, the suitability and availability of biomass fuels are important factors. Suitability refers to the technical aspect and availability refers to the economic aspect.

Combustion technology for biomass boilers also continues to develop so that efficiency continues to increase. From the beginning in the form of static grates to dynamic moving grates such as chain grates and reciprocating grates, even fluidized beds. And to get optimal performance, biomass fuel specifications must also match the shape, size, calorific value and dryness. If the specifications do not meet the requirements of the combustion technology in the boiler then of course the performance will not be optimal. For example, chain grates are suitable for using fuel that has a uniform size and low water content such as palm kernel shells, wood chips and wood pellets. Apart from that, biomass fuel with ash content which has a high melting point is highly preferred so that the ash does not melt and clog the chain lattice cavity.

Meanwhile, using a reciprocating grate, this system is very reliable for burning biomass with high moisture content (up to 60%), non-uniform size, and high ash content, such as empty oil palm fruit bunches (EFB), bark, and municipal solid waste (MSW). The combustion system moves back and forth periodically (like a moving staircase that moves back and forth) which functions to mechanically turn and stir the fuel. And for fluidized beds, this system has the highest thermal efficiency (>89%) and is very suitable for biomass with very small size (powder/dust), low calorific value, or fluctuating chemical content such as rice husks, sawdust, and coffee grounds. The biomass particle size must be maintained within certain limits so that it can float and fluidize perfectly with the sand bed media. The ideal particle size for a fluidized bed boiler (FBC) generally ranges from 0.1 mm to 10 mm (maximum 30–50 mm for certain components), depending on the specific type of technology used.

As a country located on the equator with a tropical climate, Indonesia is a biomass paradise in the world; read more here. A wide variety of biomass fuels in large volumes can be sourced in Indonesia. The most readily available biomass fuels in Indonesia today are wood chips, palm kernel shells, and wood pellets. Wood briquettes are also available but in limited quantities. Choosing the right biomass fuel will ensure optimal boiler performance, but of course, the economic factors for each metric ton of high-pressure steam produced are equally important. 

Ideally, biomass fuel is available in large quantities, ensuring affordability and high quality. The price of biomass fuel is influenced by various factors, including availability, location, logistics infrastructure, and transportation costs. Furthermore, if the biomass fuel undergoes processing, such as wood pellets and briquettes, production costs also contribute. Palm kernel shells for industrial boiler use in Indonesia require almost no processing; they are simply collected from palm oil mills or CPO mills, which produce waste in the form of palm kernel shells (PKS).

There is a case study regarding the selection of this biomass fuel involving a multinational company. In a certain country, the company’s boilers operate using wood briquettes—specifically, industrial briquettes produced by a mechanical press. This approach was also planned for the company’s plant in Indonesia. However, because producers of wood briquettes are still very scarce in Indonesia—making it impossible to secure a supply—the company ultimately conducted various experiments and trials with different types of biomass fuels and now operates its boilers using wood pellets. Thus, in addition to technical factors, economic factors are also crucial for ensuring optimal and sustainable biomass boiler operations. The trial phase is a critical step in achieving these conditions. 

Strengthening Sustainability Efforts by Reducing or Eliminating the Use of Chemicals in Palm Oil Mill Boiler Feedwater Treatment

A lot of palm oil companies now have sustainability certificates, such as ISPO (Indonesian Sustainable Palm Oil) and RSPO (Roundtable on Sustainable Palm Oil). To market palm oil and its derivatives to Europe, the European Union has implemented the EUDR, or European Union Anti-Deforestation Regulation. This regulation requires every business actor to prove that their palm oil does not originate from deforested land after the deadline of December 31, 2020. The EUDR itself will be implemented on December 30, 2026, for large and medium-sized companies. Sustainability certifications such as ISPO and RSPO are not the same as EUDR compliance, but they complement each other. This is because ISPO or RSPO serve as important tools to strengthen traceability and due diligence to comply with the EU's anti-deforestation regulations. Once certified, ISPO or RSPO simply add detailed spatial geolocation data to fully comply with the EUDR standard.

As the decarbonization trend continues to penetrate various sectors of life, various efforts aligned and relevant to decarbonization and aspirations will become a concern, even an option, and even an obligation. Sooner or later, these climate-smart efforts will become increasingly accepted and become an integral part of human life. For example, the palm oil industry is currently moving towards the use of electric vehicles in the plantation sector. The use of electric vehicles has the potential to provide added value, especially for companies that have obtained sustainability certifications such as the RSPO and ISPO. The use of electric vehicles allows palm oil companies to claim reduced fossil fuel use and reap sustainability benefits.

Another example is the use of organic fertilizers or biofertilizers. The use of biofertilizers or organic fertilizers can have several positive effects on environmental sustainability, as they can reduce the use of chemical fertilizers by up to 25%. This effort not only reduces environmental pollution and health risks but also enriches biodiversity and supports climate-smart agriculture. In an era where sustainability is a focus and a "selling point" for products (especially in Europe), this effort is very effective. This is especially true given the intense competition from other vegetable oils, such as soybean oil and sunflower seed oil.

This is also closely aligned with water treatment, particularly boiler feedwater treatment, which uses less or no chemicals. This also reduces environmental pollution and health risks. Boilers can be considered the "heart" of palm oil mills, converting water into high-pressure steam to power 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 is not only uneconomical due to high maintenance and operational costs but also dangerous. Good and well-maintained water quality will ensure the boiler's lifespan meets or even exceeds standards.

The average lifespan, which is the technical and economic life of a palm oil mill boiler, is 20 years, and by maintaining water quality, it is expected to be 20% longer, to 24 years. In addition to the technical and environmental benefits, there are also economic benefits. A palm oil mill with a capacity of 45 tons of fresh fruit bunches (FFB) per hour using electrochemical technology will achieve an estimated annual savings of over 250 million rupiah. For more detailed information, please contact us. Currently, according to data from the Indonesian Ministry of Agriculture, the number of palm oil mills in Indonesia is recorded at around 1,200 to 1,500. This is understandable, considering the increasing area of ​​oil palm plantations, currently reaching nearly 17 million hectares, thus increasing the need for palm oil mills.

Why make calculations or simulations for a palm oil mill with a capacity of 45 tons of fresh fruit bunches (FFB)/hour? This is because this capacity is the average capacity of palm oil mills in Indonesia. For example, one of the largest palm oil companies, PT Astra Agro Lestari (AALI), has 32 palm oil mills with a total capacity of 1,570 tons of fresh fruit bunches (FFB) /hour, or an average of 49 tons of FFB /hour, which is close to a capacity of 45 tons of FFB /hour. And with the number of mills in Indonesia, say 1,500 units and each mill can save 250 million rupiah/year, there will be an estimated savings of 375 billion rupiah per year from this boiler feed water treatment, in addition to technical and environmental benefits, especially to strengthen sustainability efforts to meet EUDR requirements.

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. 

Not Only Reduce Steam Cost, but Also Reduce Water Treatment Cost for Boiler Feed Water and Even Also Increase Revenue with EFB Cogeneration

Even though biomass waste is abundant in palm oil mills, the use of efficient boilers is also needed. Efficient use of biomass waste according to the type/specifications will also provide additional benefits for palm oil mills. The longer the biomass waste, the more diverse its uses, ideally even zero waste. Apart from mesocarp fiber which is usually used 100% and added with a number of palm kernel shells (PKS) and sometimes also a few empty palm fruit bunches (EFB), an efficient boiler will optimize the type and amount of biomass. For example, PKS as a commodity that can be sold are used as little as possible for boiler fuel, so that more can be sold which increases the profits of the palm oil mill.

Photo taken from here

Is a utility business like buying steam from another company needed? Utility businesses like selling steam, heat, or electricity are indeed starting to emerge; for more details, read here. Certain companies are greatly helped and receive utility products according to their wishes. They do not want the hassle of operating a boiler, including sourcing its fuel. However, for palm oil mills that in their operations produce a lot of biomass waste that can be used as fuel, it is more practical and efficient to operate their own boiler. And this has been a common practice in palm oil mills for a long time. Therefore, cooperating with a utility company to obtain steam and electricity is not an effective solution. The effective solution is the use of an efficient boiler as explained above.

Apart from that, regarding boiler feed water to increase efficiency or reduce costs and be environmentally friendly, AOP (Advanced Oxidation Process) technology, namely an electrochemical device, is used. With this method, apart from not using chemicals so it is environmentally friendly, it will also increase the service life of the RO (reverse osmosis) membrane which is the heart of the water treatment unit. Not only will the RO membrane have a longer service life, but also the activated carbon filter and ion exchange resin, which are stages of water treatment. Apart from being environmentally friendly, this technology is also more in line with the sustainability mission.

And regarding boiler operations, even to increase the volume of PKS that can be sold, cogeneration of empty palm fruit bunches (EFB) can be carried out. In this way, the EFB, which have been waste biomass which pollutes the environment and which most palm oil mills have not yet processed, are then burned to produce heat and potassium ash. The potassium content above 30% in the ash will make quality fertilizer that can be sold or used in your own plantation. Meanwhile, the heat from burning EFB is used as additional energy for the boiler (cogeneration). In this way, 100% of PKS can be sold and even exported.

If the use of PKS for boiler fuel reaches 50% then using this technology means that 50% of the  PKS can be recovered or taken back or 100% of the PKS can be sold or even exported. For example, a palm oil mill under normal conditions can sell 2,000 tons of PKS/month, then by using this technology the palm oil mill can sell 4,000 tons of PKS/month. Of course the increase in PKS supply volume is very significant to increase income, for more details read here. 

Hydraulic Press Type Biomass Briquettes, Efficient for Small Capacity

Wood processing factories and sawmills that produce small amounts of wood biomass waste, such as 5-10 tons per day, can process it into value-added products, namely briquettes. Briquettes and pellets both use biomass densification technology, but pellets are far more popular than briquettes. Wood pellets are typically used for large-scale power plants with annual demand of tens or even hundreds of thousands of tons. Briquettes (wood briquettes) are typically used for smaller capacities, and there are also wood briquettes for special applications, such as charcoal and BBQs. The question is, which type of wood briquette is suitable for this small amount of waste?

Compared to wood pellets, which only use one type of production technology—a roller press—wood briquette production uses three types: piston press, mechanical press, and screw press. For more details, read here. Of the three, hydraulic wood briquette is the most suitable type for processing this "small" amount of waste. This is because it uses the least electricity, can operate automatically, and is stable, even for 24/7 operation. The sawmill and wood processing industry, in addition to achieving clean production units (zero waste), also benefits from contributing to renewable energy.

Technically, briquette production is also easier than pellet production, due to the looser moisture content and particle size. Even for abrasive biomass materials, briquetting, particularly with piston presses and hydraulic presses, can handle these materials more effectively than roller-press pelletizing. The wear and tear on equipment in pelletizing these materials is much greater, while in briquetting, this is much less. This is because the contact area during pressing/compaction in pelletizing is much larger than in briquetting. Therefore, in briquetting, it is easier to replace certain machine components that wear out due to abrasive materials, unlike in pelletizing, which requires replacing dies and even rollers.

As the era of decarbonization accelerates, the use of renewable fuels, particularly biomass, such as wood waste, is also growing. Briquetting, particularly hydraulic press briquettes, simplifies handling and use in furnaces. Biomass boilers that feed fuel manually will easily utilize these hydraulic press briquettes. Small and medium-sized industries using small boilers will be able to utilize these hydraulic press briquettes.

Optimization of Palm Oil Mill Operations to Maximize Profits by Utilizing EFB Waste

As a profit-oriented company, palm oil companies will also do various things necessary to maximize their profits, both in the operations of their palm oil mills and on their plantations. The more efficient the operations of the palm oil mill, as well as on its plantations, the higher the profits obtained. Minimizing the environmental impact of waste produced, even zero waste, and becoming part of responsible and sustainable environmental management practices, including part of climate solutions, are important parts of this industry that cannot be abandoned. That is why palm oil mills must innovate to achieve optimal conditions. To achieve these conditions, it can be done by evaluating current practices and finding better solutions.

CPO (crude palm oil production) requires steam for the sterilization process. This is why palm oil mills definitely need boilers for their production process, for more details read here. Steam from the boiler is also used for power generation with steam turbines to drive generators. The operation of the boiler is generally carried out by burning fiber (mesocarp fiber) and some palm kernel shells / PKS, so that some palm kernel shells /PKS can still be sold or even exported. This common practice in palm oil mills has also been running for decades, but it turns out that there is still a lot of biomass waste from palm oil mills that has not been utilized, especially empty fruit bunches or EFB (empty fruit bunches) which account for around 23% of the fresh fruit bunches (FFB) processed. These EFBs are usually only piled up behind the palm oil mill and tend to pollute the environment.

The EFB can be processed into biochar. Biochar production with thermal processes, either pyrolysis or gasification, will produce energy as cogeneration in palm oil mills. Cogeneration is the right solution for biochar production while supplying energy needs for boiler operations. In this way, 100% of palm kernel shells / PKS can be sold or even exported, meaning that palm oil companies' profits are greater. But to maximize biochar production, pyrolysis is the right choice. This is because gasification technology is to maximize gas products while pyrolysis is to maximize solid products (biochar). By-products from pyrolysis are also beneficial for the palm oil industry.

Empty fruit bunches (EFB) are solid waste from palm oil or CPO production which is the largest in number. This is what makes many machine manufacturers make these EFB processing machines. Most of the machines made are equipments for cutting and pressing the EFB so that the water content decreases and the material size becomes smaller. However, both the water content and the size of the EFB as the output of the machine or equipment still do not meet the requirements to be further processed into biochar. The typical output is more than 4 inches and the water content is more than 45%. EFB must have a low water content of 10% and can be less than 1 inch for biochar production or as fuel in the boiler.

  

To obtain the EFB with a dryness level or water content of 10%, waste heat recovery from palm oil mills can be utilized for the drying process. Other biomass waste from the palm oil industry can be utilized as fuel or a source of heat energy for drying the EFB. By utilizing these biomass wastes, mill operations can be more efficient so that profits are maximized and environmentally friendly with zero waste. 

Cogeneration in Palm Oil Mills with Pyrolysis, Initial Steps in Biochar Production and Implementation

The analogy is like cofiring carried out in coal-fired power plants by mixing biomass fuels with a certain ratio as an effort to decarbonize the energy sector in power plants. While in palm oil mills, cogeneration with pyrolysis is an innovative initial step to enter the carbon negative era with the application of biochar, the main product of pyrolysis. And because all palm oil mills use biomass fuel for their mill operations, they are already based on carbon neutral fuel, unlike coal-fired power plants which are based on carbon positive fuels because they come from fossils.

Unlike cofiring which mixes coal and biomass fuels with a certain ratio and then burns them together in a furnace such as pulverized combustion, cogeneration is done by producing energy separately but the energy output is for the same use or especially the same boiler. This is done because the types of fuels may be different, such as solid fuels with liquid fuels or the technology for producing the energy is different. With this cogeneration, it means that not all energy is produced from one energy source or energy from cogeneration is a secondary energy source to meet total energy needs, and in the case of cogeneration in this palm oil mill, energy from combustion is still the primary energy.

Then why not just do full pyrolysis? It is easier, gradually for palm oil mills to adopt pyrolysis technology and its characteristics. Because (slow) pyrolysis aims to maximize solid / biochar, the by-products in the form of excess energy (syngas and biooil) as a source of boiler fuel, the calorific value is not as much as combustion which is indeed intended to maximize heat. Only about 1/3 of the excess energy contributes (cogeneration) as boiler fuel. In other words, if full pyrolysis is carried out directly, the amount of biomass as raw material for pyrolysis becomes 3 times greater or the pyrolysis unit becomes very large so that all palm oil mill biomass waste is used, and the mill cannot sell its palm kernel shells.

What are the benefits obtained by palm oil mills if they carry out cogeneration with pyrolysis for biochar production? Among the biochar products, it can save fertilizer use in oil palm plantations, overcome the problem of empty oil palm bunches (EFB) so that palm oil mills can achieve zero waste, palm kernel shells (PKS) that have been used for boiler fuel can be sold to increase income, the productivity of fresh fruit bunches (FFB) of palm oil increases, the application of biochar in palm oil plantations is also a climate solution (carbon sequestration / carbon sink) so that it can get carbon credit compensation and with good waste management, even zero waste and the application of biochar in palm oil plantations, palm oil companies will get a good image in terms of the environment and sustainability.
 

Utility Business for Palm Oil Mills

When the priority is to obtain the maximum profit, good environmental management and ease, efficiency and stability of production as an option, then utility matters at the palm oil mill may be collaborated with other parties. This specialization becomes important because of the priority choices above. The utility problems in question are electricity and steam. Electricity is produced from a steam turbine and steam is produced from a boiler. High pressure steam enters the steam turbine to drive a generator and produce electricity and low pressure steam output from the steam turbine is used for the fresh fruth bunch (FFB) sterilization process. Water treatment for boiler feed is also part of the utility problem, as well as for boiler operations to produce output in the form of electricity and steam.

Regarding cooperation or business models, palm oil mills can pay for the electricity and steam they receive. But because the fuel or energy to produce electricity and steam comes from palm oil mills, of course the price is cheaper. If currently almost all palm oil mills use their boiler fuel from mesocarp fiber and palm kernel shell (PKS), then with this specialization it is possible for palm fiber (mesocarp fiber) and empty palm fruit bunches (EFB) to be used as fuel or energy sources while palm kernel shells (PKS) can 100% sold and even exported. Palm kernel shells (PKS) as biomass fuel can be sold directly and are in great demand, and are also the main competitor for wood pellets in the global biomass fuel market.

Under these conditions, there are efforts to increase the efficiency of utility production such as steam and electricity as optimally as possible, not only combustion technology with static grates, moving grates, reciprocating grates to fluidized beds, but it is even possible to use pyrolysis. EFB or empty palm fruit bunches, which were previously unprocessed and were an environmental problem, can become a potential energy source so that 100% of the palm kernel shells / PKS from palm oil mills can be commercialized/sold. And even if the utility provider uses pyrolysis, biochar will also be obtained. Biochar provides many benefits related to soil fertility and climate.

Future Palm Oil Mill: Producer of CPO, Biochar and Hydrogen at the Same Time

Efficiency factors, optimizing potential and improving climate should be implemented simultaneously in the palm oil industry. This can be done by replacing the combustion furnace in the boiler with pyrolysis so that the boiler fuel is mainly biooil, a pyrolysis by-product, with the main product being biochar and building a biogas unit for hydrogen production as the final product. Biochar will be used as a soil amendment together with fertilizer so that it becomes slow release fertilizer, so that fertilizer use efficiency (NUE: nutrient use efficiency) increases. The use of biochar as carbon sequestration, namely by using it together with fertilizer, will also provide additional income from carbon credits. Acid soil or dry soil will have better fertility with the application of biochar.

Furthermore, liquid waste or POME (palm oil mill effluent) is used as raw material for biogas. With the main component of biogas being methane (CH4), with steam reforming the methane will react with steam at a temperature of 700-1100 C with a nickel catalyst to become hydrogen/H2 and carbon monoxide/CO. To maximize hydrogen H2 production, the resulting carbon monoxide / CO is then subjected to a shift reaction, resulting in hydrogen / H2 and carbon dioxide / CO2 products. The reaction runs at a temperature of 400-500 C or at a lower temperature, namely 200-400 C. At higher temperatures the shift reaction usually uses an iron oxide or chromium catalyst, while at lower temperatures the catalysts usually used are copper, zinc oxide and alumina. , which helps reduce CO concentrations to below 1%.

Why Is It Better For Palm Oil Mills To Use Pyrolysis Rather Than Combustion Furnaces?

The palm oil mill production process or CPO production always requires steam for sterilization, this means a boiler is needed. The heat needed by the boiler usually comes from a furnace with fuel in the form of mesocarp fiber and palm kernel shells. Apart from being used for sterilization, the steam is also used to rotate turbines and produce electricity. With continuous pyrolysis, heat for the boiler can be supplied from syngas and biooil products. Apart from that, pyrolysis also produces biochar as the main product and pyroligneous acid, which is a kind of wood vinegar. The last two ingredients will be very useful in palm oil plantations. Using these two fuels (gas and liquid fuel) will make the furnace produce cleaner smoke compared to burning solid fuel in the form of mesocarp fiber and palm kernel shells which is usually done up to now.

Many palm oil plantations are on acidic soils so the pH needs to be raised and biochar can be used effectively. The biggest operational cost for palm oil plantations is fertilizer and the use of biochar will increase fertilizer efficiency thereby reducing fertilizer input and saving costs. The application of biochar in palm oil plantations apart from improving soil quality thereby increasing the productivity of palm oil fruit or FFB (Fresh Fruit Bunch) is also part of the climate solution, namely carbon sequestration which receives compensation in the form of carbon credits. The carbon credits will also provide additional income for the palm oil company. Apart from that, pyroligneous acid can also be used as fertilizer and biopesticide.

The development of combustion technology is also increasingly developing, starting with the use of moving grates to reciprocating grates used to increase boiler efficiency. But the basic question is how profitable is the use of this technology for palm oil companies in overall? The use of the combustion furnace only increases the efficiency of the boiler, whereas the use of continuous pyrolysis in addition to sufficient boiler heat can also produce other benefits in the form of environmental and financial benefits. Environmental benefits from improving soil fertility conditions and minimizing fertilizer being leached or lost into the environment with the slow release fertilizer technique, for more details read here and also the income from carbon credits which is also big.

The application of biochar is for palm oil plantations, while biochar production is from palm oil mills, while the plantation division and mill division are two separate organizations within the palm oil company. The role of the general manager in particular is needed to handle this so that the company's big goals as a profitable, environmentally sound and sustainable company can be achieved. Factors in the form of maximizing profits, improving land and the environment, as well as being part of the climate solution with carbon sequestration will be a strong driving force for the use of continuous pyrolysis compared to combustion furnaces.

Increasing Energy Efficiency in Palm Oil Mill Operations Using Pyrolysis

Energy utilization in the form of steam production which is then used for electricity production through steam turbines and generators, as well as the use of steam for steamming (sterilizing) fresh fruit bunches (FFB) are the main things in palm oil mill operations. This is because the need for electrical energy to power various mechanical equipment in the mill comes entirely from this electricity production. Electricity and steam for industrial processing are grouped under the utilities that support that industry. Meanwhile, in the sterilization process or the boiling of FFB, steam besides stopping the development of FFA (free fatty acid) and facilitating the threshing will also facilitate the CPO extraction process and processing the kernel (palm kernel). To produce steam and electricity, of course, energy is needed, namely heat. Steam is produced by the boiler in the form of superheated steam to drive steam turbines and generators to produce electricity and then steam from electricity production or low pressure steam is used for steamming (sterilization) of FFB.

The water after being treated so that it becomes BFW (boiler feed water) is then used for the production of steam and electricity. Heat energy to produce steam can be reduced in such a way with the use of a pyrolysis process (which means that it is not ordinary combustion), so that the heat requirement for the boiler furnace is getting smaller. The pyrolysis condenser will produce hot water so that it becomes preheating for the boiler. In pyrolysis a condenser is used to separate bioil and syngas (uncondensable gas). Preheating from the condensation process of the pyrolysis unit will then go to stage 2 preheating in the economizer of the boiler unit. Thus the temperature of the water entering the upper drum on the boiler is high enough, and the heat requirement to become superheated steam will be reduced. The palm oil mill uses a water tube type boiler as is commonly used in large industries and not a fire tube which is in the form of a shell and tube type heat exchanger with the tube submerged in water so that it does not overheat. In a water tube type boiler, it consists of an upper and lower drum (mud drum) which is connected to a pipe. The lower drum and water tube are fully filled with water, while the upper drum is only partially filled. With this arrangement, steam will pass through the mechanical separator on the upper drum, flow to the superheater and exit the boiler. Efficiency is the key word in production, including the use of energy in the production process of CPO or palm oil mills. The rule of thumb is an increase of 10 C in BFW is equivalent to increasing 1% boiler efficiency.

Typical of water tube boiler

Excess energy from the pyrolysis process should be used for fuel or energy sources in the boiler furnace. The use of excess energy from pyrolysis will also produce environmentally friendly flue gas emissions because the combustion of liquid and gaseous fuels will be cleaner than solid fuels. In this way, the palm kernel shell, which has been used for boiler fuel, can no longer be used. All these palm kernel shells or PKS can be sold directly and even exported to Japan and Korea. Of course, be a separate source of additional income. Palm kernel shells or PKS are competitors for wood pellets in the global market because they have many similar properties, but because palm kernel shells come from waste or palm oil mill sideproducts, the price can be cheaper, more information can be read here. The use of slow pyrolysis for biochar production is the best option compared to similar technologies such as fast pyrolysis and gasification, more details can be read here. Palm oil mills or companies will get a lot of benefits from biochar production, for more details can be read here.