OPT Briquette and EFB Briquette for Medium Capacity Industrial Biomass Boiler Consumption

The growing utility business, specifically the provision of steam and electricity for renewable energy-based industries, particularly biomass, has led to a growing need for biomass fuel. This also applies to industries using their utility units to produce steam and electricity using biomass fuel. In addition to biomass fuel, water quality, the raw material for steam and electricity production (using steam turbines), is also crucial and must be considered. Good water quality will ensure optimum steam and electricity production performance, and the longevity of equipment (boilers, heat exchangers, steam turbines, and cooling towers), and vice versa. Good water quality is like healthy blood for our bodies, enabling all organs to function optimally.

Palm oil industry solid waste is a potential raw material for biomass fuel. This solid waste is empty fruit bunches (EFB) and oil palm trunks (OPT). EFB is produced from palm oil mill operations with a percentage of approximately 22% of fresh fruit bunches (FFB), while oil palm trunk waste is produced from replanting programs of oil palm plantations, which are also very abundant. For more details, read here. Utilizing both of these biomass wastes for the production of biomass fuel, especially biomass briquettes, would be very good. But why are they processed into briquettes?

The advantage of briquettes over pellets, aside from technical advantages, lies in their scale. Briquette production requires a looser particle size and lower moisture content. Energy consumption per ton of briquette production is also lower than that of pellet production. This makes EFB briquette and OPT briquette production more suitable for a palm oil mill serving medium-sized industries. A palm oil mill with a capacity of 45 tons/hour of FFB will produce approximately 10 tons/hour of EFB. With a 20-hour daily operation, approximately 200 tons will be produced per day. With a moisture content of approximately 60%, this means that after drying, approximately 100 tons/day (10% moisture content) will be produced, or 2,500 tons/month.

Likewise, when using oil palm trunk (OPT) waste as raw material, it depends on the ratio or percentage of land replanted each year. Replanting itself is an effort to continuously maintain the productivity of the oil palm plantation itself, in addition to the use of superior seeds and intensification. For more details, read here. For example, with a land area of ​​10,000 hectares and each year replanting 5% of the land, or 500 hectares. With an average of 125 trees per hectare of oil palm plantation and each tree having an average dry weight of 0.4 tons, then per hectare obtained 50 tons of dry weight of biomass. With an area of ​​500 hectares, this means 25,000 dry palm trunk biomass (10% moisture content) each year or can be processed into OPT briquettes with a capacity of around 2,000 tons/month.

Biomass boilers, used for producing biomass briquettes (EFB briquettes/OPT briquettes), can utilize various combustion technologies, such as moving grates, stokers, reciprocating grates, and so on. The choice depends on the cost or price of the boiler and its efficiency. In addition to biomass fuel, to align with decarbonization and sustainability programs, water for boiler operation, including boiler feedwater and cooling water for heat exchangers (heat exchangers/condensers), is crucial. This is likened to blood for the human body; healthy blood ensures optimal function. If impure blood circulates throughout the body, for example due to kidney failure, organs will automatically be damaged, and a person will soon die.

To maintain water quality for steam production through a boiler, boiler feedwater/demin water must strictly comply with the boiler's operational specifications. The higher the boiler pressure, the higher the water quality or purer the water required. If the steam is used for electricity production, after the steam drives the turbine, it needs to be condensed in a heat exchanger (condenser) so that it changes phase back to liquid and enters the boiler again. This heat exchanger requires cooling water that is continuously used repeatedly, thus requiring a cooling tower. Not only does the boiler feedwater/demin water need to meet the required technical specifications, but so does the cooling water for this condenser. With water volumes circulating up to thousands of tons per hour and operating 24 hours a day (the same as boiler operations) in the cooling tower, a number of water problems in the cooling tower need to be addressed effectively and efficiently. A number of water problems that occur in cooling towers can be read here.

In addition to electricity production, steam is also used for processes within a specific plant. If the steam is then condensed, then liquid, and returned to the boiler, this requires a cooling tower, just as in electricity production. Efficient and environmentally friendly water treatment technology, which eliminates secondary pollution and is easy to operate and maintain, aligns with the vision of decarbonization and sustainability. This vision of decarbonization and sustainability will be even more optimal or ideal for utility units, namely the use of biomass-based renewable energy and environmentally friendly water treatment technology. 

Industrial Wood Briquette Becomes an Alternative Between Wood Chips and Wood Pellets

Biomass fuel is a renewable fuel or renewable energy that is currently positioned as one of the alternative fuel. However, along with awareness of various climate problems, the use of alternative energy from biomass has increased over time. The decarbonization trend as a response to climate problems has penetrated all lines of life including the industrial sector. As a profit-oriented industry, of course, efforts to maximize are a major concern, including in the use of alternative fuels. There are various types of fuels that can be produced from biomass and especially for solid fuels, including wood chips, wood pellets and wood briquettes. The characteristics of these fuels are slightly different from one another, including their production costs. It is necessary to look more carefully and deeply so that you can get the best biomass fuel according to the goals of the industry.

Industrial briquette can be produced in large quantities at a lower cost than briquette produced with hydraulics or extruders. And when compared to wood pellets, industrial wood briquette is also cheaper to produce. But of course the production cost is more expensive than wood chips. Wood chips can be said to be the easiest and cheapest biomass fuel to produce.

This places industrial wood briquette in a position between wood chips and wood pellets or hydraulic and extruder type briquettes. As a biomass densification product, industrial wood briquette is also more economical for long-distance transport. In addition, a number of industrial boilers have also been specially designed to be able to use industrial wood briquette fuel, even with automatic feeding. Other factors such as uniformity of shape, size can vary and low water content are other advantages of industrial wood briquette.

Boiler users in industry and even coal power plants can consider using industrial wood briquette. Especially for companies engaged in industrial utilities such as steam providers for processing industries so that the operation and maintenance of the boiler including the use of biomass fuel is the responsibility of the company. With a long-term steam supply contract, for example around 5-10 years, the provision of biomass fuel in the form of industrial wood briquette within that period is also very important. In addition to the availability of sufficient, legal and sustainable raw materials, the reliability aspect of industrial wood briquette production machines cannot be ignored.

 

Case Study India: Priority of Biomass Pellet Production Over Biomass Briquette

There are dozens of biomass briquette machine manufacturers in India and almost all of these machine manufacturers use mechanical press technology for the production of these briquettes. With this technology, briquettes will be formed due to mechanical press such as repeated strokes every minute (about 220 strokes per minute). This briquette machine manufacturer industry has also existed for decades in India so that biomass briquette products have also been widely known in India. Technically, there are actually 2 other technologies for the production of biomass briquettes, namely screw press and hydraulic press. Based on the briquette production technology, the briquette product output is also slightly different, for more details, read here.

The Indian government launched a decarbonization program at their coal power plants, recently, namely on October 8, 2021 which ordered the use of 5% to 10% biomass pellets for cofiring at all power plants and took effect in October 2022 or one year is the target time set. For example, in the early stages, the Indian government targeted only 5% for the cofiring ratio in their coal power plants, where the 5% figure when translated into biomass pellet production would reach around 50 million tons of biomass pellets per year. A very large number especially with a very short target time. And with a cofiring ratio of 5%, coal power plants also do not need to modify their equipment even though the biomass pellets used come from agricultural wastes, whose quality is below that of woody biomass.

With the number of power plants reaching about 900 units with an average consumption of 50 thousand tons of biomass pellets per year or a total of almost 50 million tons per year, so that a biomass pellet factory with a capacity of around 5 thousand tons / month seems to be suitable, and even if each factory supplying one power plant, the need for a biomass pellet plant will also be the same as the number of power plants, which is 900 units. A huge amount.

Production of biomass briquettes or biomass pellets?
In India, biomass briquette is indeed more popular than biomass pellets, but for the world level pellets are much more popular than briquette, even in 2021 alone, the need for pellets for global power generation alone is estimated to have reached 23 million tons. In addition, the production or pellet factory in general is also larger than the briquette factory. There are many pellet factories with a capacity of 5 thousand tons or even 10 thousand tons per month, while for briquettes it is very rare for a biomass briquette factory to have a capacity like the pellets above. Pelletisers for pellet production for commercial capacity have a capacity of 3 tons/hour or more, while briquette machines are generally less than 2.5 tons per hour, even for the screw press type the average machine capacity is only 300 kg/hour. Technically, even though they are both products of biomass densification technology with the difference that the size of the briquettes is larger than pellets, the production of briquettes is easier than pellets. 

The driving force from the business side makes biomass pellet production more attractive, especially because of its need as cofiring fuel in coal power plants as part of the decarbonization program. The need for biomass pellets can be a driving force for the production of biomass pellets or in general, namely the economy in various regions. The program should also be able to provide three benefits at once, namely environmental, social and economic. In addition, because briquette products are mainly used for boilers in industry, while pellets are for power generation, both of them also have their own market segments so that there is no market competition.

What about the Briquette Machine Manufacturing Industry?
Dozens of industries producing biomass briquette machines should now see this as an opportunity so that they can respond to it. These industries can adapt by creating a new line of business, namely helping the manufacture of a biomass pellet factory. Technically, the biomass briquette production line with biomass pellets also has many similarities (both use biomass densification technology) with the main difference being the pelletiser and briquetter. A number of equipment that can be made themself will reduce imported machines. Pelletisers are almost certain to be imported, so the selection of pelletisers as the heart of the pellet production process must be of high quality so that the pellet production target can be achieved. In the production of large capacity pellets, a number of equipments come from a number of providers, as is common in wood pellet factories with a more detailed explanation here.

In the long term, the goal is to minimize import spending, and even 100% can be made or fabricated by themself. This effort will usually take longer because the complexity of the pelletiser is higher than that of the briquetter. These briquette machine-producing industries can also cooperate with machine manufacturers in Europe who are more experienced and proven with pellet production as an effort to accelerate the transfer of the technology. Within one year as the target was set, it is very difficult to do this, so the practical effort is to buy a 100% complete line from a proven vendor, or sort out a number of equipment that can be produced yourself as above and gradually substitute the imported equipment. This is because achieving the production target for the decarbonization effort is a priority.

In conclusion, at this time India has to maximize efforts to accelerate the construction of biomass pellet factories to achieve this target. However, 1 year to achieve this target is very difficult. With these conditions in the future, it is possible that power plants in India will import biomass fuels such as wood pellets and PKS (palm kernel shell) to meet their needs. With the planned cofiring ratio, which is the lowest target of 5%, the need for biomass pellets reaches around 50 million tons, if only 2% of the biomass fuel needs are imported, both PKS and / or wood pellets, it will reach 1 million tons, a fixed amount still quite big.

Briquetting of Pineapple Plantation Waste

Pineapple is a fruit that is quite popular throughout the world, this can be seen from the percentage of pineapple fruit production in world fruit production which reaches 8%. Pineapple plants are almost the same as banana trees, that is, after bearing fruit once, the plant dies, and then the production is continued by the saplings for several generations. Or more specifically, pineapple plants produce after 1-2 years of planting and die after fruiting and produce about 70 leaves. The pineapple plants will be dismantled after two or three harvests to be replaced by new plants, which results in increasing pineapple leaf waste. Currently there is almost no utilization of this waste and pineapple leaves also cannot be used for animal feed, so they are only burned or thrown away which also causes environmental pollution. In every hectare of pineapple plantation, the waste produced can reach 3 tons. Large pineapple plantations are usually with an area of  thousands or even tens of thousand of hectares so that the production of this waste is also very much. Handling pineapple leaf waste with an effective and efficient method will certainly provide added value when examined from an economic point of view, so it is necessary to make efforts to handle this waste and briquetting  can be the perfect solution to this problem.

Although both use biomass densification technology, briquetting of pineapple leaves and stems is easier and cheaper than to make pellets. The production of pineapple leaf briquettes can then be used for cooking fuel, industry and even electricity generation. In addition, pineapple leaf briquettes are also used to increase biogas production. There are large pineapple plantation companies that have cattle farming businesses. Cattle farms are chosen mainly because they can use pineapple skin or fruit waste to feed the cows. And because the volume of pineapples produced is also very large, the fruit waste is also large and the cattle farm that is made is also large. The cow manure is usually further processed for biogas production and the digestate of biogas then composted. The compost produced is reused in the pineapple plantation. The briquettes of pineapple leaves and stems added to the substrate or co-digestion will further increase the biogas production significantly. Read here for more details.

With a scenario like the one above, almost all of the biomass waste generated from the pineapple plantation and industry can be utilized optimally. Likewise, the waste from a side business in the form of cattle farming for biogas production. In addition to large pineapple plantation companies, pineapple production centers in Indonesia such as Subang, Pemalang, Prabumulih, Kediri, Blitar, Kubu Raya, Mempawah, Muaro Jambi, Kampar, Central Lampung and Karimun can also develop the above concepts.

Estimated Increase in POME Biogas Production in Indonesia and Malaysia with the Addition of Biomass Briquettes

 

The important thing that needs to be done to implement a research in a commercial unit is the technical and economic side. A research product that has been tested technically needs to be evaluated on the economic side. This is because in commercial units, the economic aspect is the main consideration for the implementation of a certain technology. A technology implemented with the intention of improving the performance of these commercial units but not providing economic benefits generally will not attract many. Likewise, vice versa. How much economic benefit can be obtained from implementing this technology? Is it worth the effort? These two questions will be considered next.

In the biogas unit (mostly for electricity production) the above rules also apply. And especially the biogas unit in Indonesia and Malaysia as the largest CPO (crude palm oil) producer in the world, the POME biogas unit or palm oil mill liquid waste has been built as a means of overcoming the problem of liquid waste and also energy production, especially electricity. Tens or even hundreds of POME biogas units have been built in Indonesia and Malaysia, but that number is not yet comparable to the number of palm oil mills in Indonesia and Malaysia which has reached thousands. And more specifically, the number of POME biogas units in Indonesia is less or a smaller percentage compared to palm oil mills compared to Malaysia. Why did this happen? For more details, please read here.

And because the commercial end product of the commercial biogas unit is electricity, the price of electricity will greatly affect the operation of the biogas unit. Research conducted at Aarhus University in Denmark shows that biomass briquettes can significantly increase biogas production, that is, every 1 tonne of straw briquettes added has increased biogas production by an average of 400 cubic meters. With a biogas caloric value of around 4500 kcal / m3, each tonne of addition of straw briquettes will increase calories by 1,800,000 kcal in the form of biogas. for more details, please read here. In the case of POME biogas, if empty fruit bunches (EFB) are used as raw material for briquettes, it could be an increase in the biogas product produced. This is because the EFB have undergone a sterilization process (steamming) so that the biomass pores are more open so that the surface area is larger. The briquetting of the EFB will also further expand the surface of the biomass so that the anaerobic fermentation process is more perfect and the biogas product increases.

Assuming the electricity price per kwh in Malaysia from biogas is 0.49 RM (IDR 1,715) and IDR 1000 in Indonesia, with the increase in biogas produced above, Malaysia will be more attractive and profitable. However, this increase in biogas production has also yielded attractive advantages when applied, both in Indonesia and Malaysia. The estimate assuming a biogas reactor capacity of 150,000 tonnes and with the addition of 15,000 tonnes of biomass briquettes (maximum 10% of the reactor volume) has resulted in profits of nearly 27 billion rupiah/Rp (application in Indonesia) and 14 million Malaysian ringgit/RM (application in Malaysia). Under these conditions, it is actually very interesting to implement this research on POME biogas power plants in Indonesia and Malaysia. Apart from reducing solid waste from the palm oil industry, increasing biogas production which is proportional to electricity production will provide attractive benefits for the palm oil industry.

Briquetting of Banana Plantation Industry Waste

Banana has been a fruit that is commonly consumed and loved for a long time. Along with the increasing need for banana fruit, a number of banana plantations were created and many of these banana plantations were large scale with up to tens of thousands of hectares. The biomass waste from this banana plantation will also be very large, such as banana trunk, bunches and leaves. Such a large volume of waste should be processed so that in addition to not polluting the environment and even causing disease in the banana tree itself, processing this biomass waste can also provide economic benefits. Briquette is an effective solution to overcome this waste. The briquette products of banana trunk, bunch and stem are used for fuel or energy sources.

To be able to briquette the biomass waste is reduced in size (down sizing ) to about 1 cm. The biomass waste with a small particle size is then squeezed to separate the water with a screw press. After the water can be separated from the waste until the water content is around 10%, then it can be briquetted. If the moisture content has not reached the moisture content, drying with a dryer can be done. The liquid separated from the waste is rich in potassium / kalium so it can be reused as liquid fertilizer for the banana plantation. Mechanical press briquette is the best option for briquette technology choices. In contrast to pelleting which only uses one technology, namely roller press, briquette there are 3 variations of technology that can be used, for more details, please read here. The briquette is also technically easier and economically cheaper to produce.

The trunk of a banana has many similarities to the stem of water hyacinth. Water hyacinth is an aquatic weed, so the number must be reduced or eliminated. Both are non-woody biomass materials such as trees. Some efforts have been made to compaction water hyacinth into pellets some time ago. Water hyacinth briquette is also very possible, in fact, the rule is that all materials that can be pelleted can certainly be briquette but not the other way around, meaning that all materials that can be briquetted cannot be pelleted easily. This is because in addition to the varied briquetting technology, the tolerance level for material properties is also looser, such as particle size and moisture content. The particle size is too fine which cannot be pelleted like pellets waste and can even be briquetted as well for larger particle sizes. Meanwhile, water content of up to 16% can still work well in briquette but cannot be done in pellet production. The level of briquette density can also be adjusted and generally briquettes are also denser than pellets, even up to 1.4 ton / m3.