Wood Chip, Wood Pellet, and Wood Briquette from Energy Plantations for Local Market Part 2

The PLN (Indonesia State Owned Electricity Company) cofiring program, which is mixing biomass fuel with coal in coal power plants, will clearly encourage the use of biomass as an energy source. Cofiring is the easiest and cheapest way for coal power plants to start entering or gradually using environmentally friendly renewable energy. Emissions are also getting better as the use of biomass fuels increases, such as because the sulfur content is very low, there is little ash instead of hazardous waste, and fly ash is very small. The amount of added biomass, for example, starts from 1% which is then gradually increased and even finally it can be 100% biomass or renewable energy. In 2020 the cofiring program has been initiated with a target of 37 coal power plants and by the end of 2020 it is reported that it has been implemented for 20 coal powerplants. While in total there are 114 coal power plants units owned by PLN that have the potential for cofiring, spread across 52 locations with a total capacity of 18,154 megawatts (MW) with a target of completion in 2024. Consisting of 13 coal power plant locations in Sumatra, 16 coal power plant locations in Java, Kalimantan (10 locations), Bali and Nusa Tenggara (4 coal power plant units), Sulawesi (6 locations) and Maluku and Papua (3 coal power plant locations). Meanwhile, the cofiring ratio ranges from 1-5% biomass with an estimated biomass requirement of 9-12 million tons per year. Technically, with the 1-5% cofiring ratio, the PLTU also does not need to modify its equipment, so that it can be used immediately after the biomass fuel meets the required specifications.

When detailed about the type of technology used by coal power plants in Indonesia today, there are three types of coal power plant, namely, 43 types of PC (Pulverized Coal) with a total capacity of 15,620 MW requiring a mixture of 5% biomass or the equivalent of 10,207.20 tons per day, 38 types of CFB ( Circulating Fluidized Bed) a total capacity of 2,435 MW requires 5% biomass or the equivalent of 2,175.60 tons per day. Meanwhile, 23 types of stoker with a capacity of 220 MW use 100% biomass or the equivalent of 5.088 tons per day. In the short term, the type of biomass used is waste based, while in the long term it is from energy plantations. The Ministry of Environment and Forestry has also allocated a land area of ​​around 12.7 million hectares for the provision of forest land to jointly support the coal power plants biomass supply program. Ex-mining lands covering an area of ​​about 8 million hectares should also be reclaimed using this energy plantation. Even PLN has also signed a memorandum of understanding or a Memorandum of Understanding (MoU) with PTPN III Holding (Persero) and Perum Perhutani. In this case, PLN is the owner of the PLTU, while Perhutani has the resources of industrial forest areas both in Java and outside Java that can be developed as energy plantations. Likewise with PTPN III which has land for the development of energy plantations, read here for more details.

To fulfill the need for biomass as an energy source, energy plantations must be increasingly encouraged. The production of biomass fuels from energy plantations takes longer than processing forestry and agricultural wastes such as felled wood waste, sawdust, wood waste from the wood processing industry, palm oil empty fruit bunches, coconut husks, rice husks, and so on. . The route or option with energy plantations was chosen because in addition to ensuring the quality and quantity of biomass fuel it also optimizes land use, including being integrated with livestock and can be harvested multiple times (coppice) without having to replant for the next harvest. In fact, because energy plantation plants use legumes such as gliricidia and calliandra, which the roots can fix nitrogen from the atmosphere, soil fertility also increases. However, more and more efforts are needed for the energy plantation route because it takes at least 2 years for these crops to be harvested and before that it also needs to prepare the soil and plant the trees.

As previously stated, the choice of production for the type of fuel from energy plantations is influenced by several factors, such as the distance between energy plantations and industrial users, production capacity, industrial needs according to combustion technology and investment cost. If the industrial location or power plant is close to each other, even in the energy plantation area, it is sufficient only to make wood chips from the energy plantation. This is because transportation costs are cheap. Meanwhile, if the location is far enough, the wood should be processed into wood pellets or wood briquette. Wood pellets are indeed much more popular than wood briquettes, although technically wood briquette production is easier and production costs are cheaper. In addition, technically, the density of wood briquette can also be higher than wood pellets. This becomes interesting if a producer is interested in wood briquette production as a product diversification and biomass densification technology.

 

For sustainability, energy plantations will also be better than the use of agricultural and forestry wastes or the timber industry as mentioned above. This is because the plantation is designed and made specifically for the purpose of wood as an energy source. This also makes the volume of wood production more certain than relying on the volume of waste, whose availability depends on the main product. Energy plantations and the following livestock businesses are likely to become an exciting new trend and hopefully the momentum will not be anymore.

Wood Chip, Wood Pellet, and Wood Briquette from Energy Plantations for Local Market

The floods in South Kalimantan in January 2021 almost drowned one province

To be able to provide benefits and maintain environmental balance, forests must be managed or according to their purpose. The conversion of forest land to palm oil plantations, housing and so on will create an imbalance in the environment as a result of which natural disasters will occur. In-depth and comprehensive studies have certainly been carried out to determine the use of the land so that its sustainability is maintained and benefits human life. When the benefits for human life, especially the economy, are a priority and dominant, then the balance of the environment is automatically disturbed and natural disasters are ready to lurk at any time. The laws and regulations that are supposed to maintain this balance are imposed and amended for that purpose. For example, regulations on the minimum area of ​​a protected forest area in an area are no longer needed or adapted to conditions so that it is very vulnerable to fraud. And when human greed is getting out of control because it is so materialistic, the nature and the environment is getting more and more damaged so that the consequences are natural disasters everywhere such as drought and forest fires in the dry season, floods and landslides in the rainy season and so on.

On the other hand, industrial forest plantations (HTI) which are intended for economic aspects must also be used optimally, as well as a number of idle lands and so on. Energy plantation is one of the best options, more details can be read here. As a source of fuel or an energy source from biomass, the wood produced in energy plantation can be processed into wood chips, wood pellets or wood briquettes. The choice of product to be produced depends on a number of things such as the distance between the energy plantation and the industrial user, production capacity, industry / market needs and investment value. The closer the industrial users or markets are to energy plantations, the simpler biomass energy products are, such as wood chips. Biomass densification such as pellets and briquettes is needed if the location of the energy plantation and the user is far away so that transportation costs are high. By densification into pellets or briquettes, transportation costs can be saved, as well as more efficient storage, easier handling and use.

Palm kernel shell (PKS) is a biomass fuel which is also abundant in Indonesia, more details about PKS can be read here. This PKS is also a competitor for biomass fuel from the energy plantation. Previously, much PKS were exported to Japan and Korea, but the imposition of high export tax and levy made the price less competitive, for more details can be read here. This also further encourages the use of PKS for industry in the country. Moreover, starting in 2022, PKS that enter Japan must also be RSPO certified or this is analogous to wood pellets with its FSC.

 

Ideally, PKS should be used for domestic industries because besides being cheap, the volume is also large. Domestic industries can be more competitive if the fuel is cheap. Meanwhile, wood pellets from energy plantations are for export orientation. In addition to the added value being greater than the wood pellet production activity itself, labor absorption is also more. However, in certain periods the supply of PKS can be disrupted, such as a decrease in the production of CPO or palm fruit during the low crop season, the location of palm oil mills in remote areas, resulting in difficulties in transportation / logistics and weather at sea. With the condition that most of the industries are located in Java and there are still thousands of hectares in Java for making energy plantations, under certain conditions energy plantations and wood product processing are quite prospective in Java. Continued.

Production of Box Shaped Hay From Gliricidia Leaves

Apart from market, feed is another important factor in livestock business. Striving for and ensuring the availability of feed throughout the year both in quality and quantity is a challenge in itself, especially industrial-oriented ruminant farms. The productivity of livestock products is largely determined by these feed factors. The important role for livestock is for the growth of young livestock and for maintaining life and producing products (milk, calves/lamb, meat) and power for adult livestock. Another function of feed is to maintain endurance and health. In order for livestock to grow as expected, the type of feed given to livestock must be of good quality and in sufficient quantities.

In addition, livestock productivity itself is influenced a lot by environmental factors, namely up to 70%, while about 30% is genetic factors. And among these environmental factors, the aspect of feed has the greatest influence, which is around 60%, for example superior sheep farming such as the dorper type but if the quality and quantity of feed is not met then the results are also not optimal. Meanwhile, in terms of livestock business, the cost of feed is also the largest production cost, namely 60-80% of the total production cost. So it is very natural that attention or focus on feed issues is very important.

Seeing the above conditions, processing technology for animal feed is important. The purposes of animal feed processing include preserving nutrition and extending shelf life. Drying the leaves of gliricidia or calliandra to a moisture content of about 15% is one such effort or commonly called hay. By making hay the two objectives of processing animal feed above, namely maintaining nutrition and extending the shelf life can be achieved, but with a large volume of dry feed or hay (bulky) it will be inefficient in using space for storage or if it is to be used in other places where need quite far transportation. This is why it is necessary to apply biomass densification technology to solve this problem. Hay compaction into blocks or box shaped is a practical and easy undertaking. The equipment and compaction process into box shaped is also easy and cheap, compared to other biomass compaction technologies such as pellets or briquettes.

A sheep or cow farm should be built near the energy plantation so that they can easily get a source of feed for the gliricidia leaves. The leaves are then made hay and compacted into the blocks / box shaped. And because gliricidia leaves are a source of protein, so to be a complete feed, another source of feed is needed. This can be fulfilled by the surrounding community with community empowerment patterns or for more details, please read here. Sources of feed from the community, for example a source of fiber from grasses or agricultural waste, can also be made hay, so that the farm is available as a complete feed (complete feed) which is safe for the operation of the farm business. And because the estimated leaf production from energy plantations is very abundant, some of the hay that is produced can also be sold elsewhere. 

Technology is basically a tool to achieve a goal. From a technological point of view, namely biomass densification, besides the raw material for glicidia leaves can be made hay, the leaves can also be made into pellets or briquettes. The main difference between pellets and briquettes is only a matter of size, briquettes are bigger than pellets. The form of puck briquettes like the photo above is the best form for animal feed applications. From a technical perspective, pellets and briquettes are also denser or have a higher density than hay. The dust problem in hay can also be reduced by making these pellets or briquettes. But it is true that making pellets or briquettes requires higher investment costs and the production process is more complex.

Biomass Boiler and Its Urgency

A problem that is visible and can be felt, especially if it has a short-term impact, is certainly easy to map and find a solution to. But if the opposite namely is not visible, it is difficult to feel and the impact or effect is long-term, of course it is more difficult to map, let alone find a solution. The use of fossil fuels, especially coal in a number of industrial boilers, is an example. The effects of exhaust emissions in the form of COx, NOx and SOx may be difficult to detect at first but create environmental damage in the long term. Likewise heavy metals like mercury which also have long-term effects. Meanwhile, fly ash pollution and boiler furnace ash (bottom ash) are clearly affected more easily. In a larger case or global scale, namely climate change and global warming due to greenhouse gases, especially CO2 (carbon dicside), a global consensus is also needed to solve these problems. That is what makes the Earth Conference on Climate Change (UNFCC) always held every year, which has so far been recorded 27 times, lastly in 2019 in Madrid, Spain, while what was supposed to be held in 2020 was postponed in 2021 due to the COVID-19 pandemic. Fossil fuels including coal are carbon positive fuels so that their use will increase the concentration of CO2 in the atmosphere, while biomass fuels such as wood chips, wood pellets, wood briquette and palm kernel shells (PKS) are carbon neutral fuels. It is said to be carbon neutral because of the use of this fuel because it does not increase the concentration of CO2 in the atmosphere.

 

Boilers are essential equipment for the operation of a number of industries. The main function of the boiler is to produce steam which is used in the industrial production process. But when the boiler is not operated and maintained properly, the boiler can be dangerous. The continuity of production operations also greatly depends on this equipment, so that disruption of boiler operations will have a significant effect on this production. The boiler also consists of a number of subsystems that work in harmony, such as boiler burners and controls, water treatment for boiler feed water preparation, fuel handling and feeding and so on. Sometimes a number of subsystems are supplied from a number of different vendors, so synchronization between these subsystems is very important. This makes boiler operations safe, efficient, reliable and minimizes boiler downtime. And of all the subsystems in the boiler, the burner system is the most sophisticated subsystem in the boiler unit. The burner system has a number of operational modes that require extensive training and / or experience for boiler operators to be well understood.

Currently, a number of industries have started to switch from fossil fuels to biomass fuels. In industries that previously used solid fuels, technical changes or furnace modifications can be minor, while in industries that previously used gas or liquid fuels, the usual thing to do is replace the boiler unit (including the furnace). Of course, the replacement of the boiler unit is also followed by its supporting systems such as fuel storage, provisioning and so on. Petroleum fuels, coal and natural gas are consistent fuels with standard quality and their contaminants or impurities have been known and studied for decades. Whereas with biomass there are a number of options and each source is also unique and also the level of contaminants.

In certain cases, industries that will switch to using biomass, namely palm kernel shells (PKS), that previously using natural gas, so the industry needs to study and analyze the implications of using the PKS. And because the use of PKS for industrial fuel is relatively new, the industry can use old data about their furncae operations with natural gas and compare it to furnace that use solid fuels like coal - which is commonly used by the industry today. Although PKS is also a solid fuel, there are a number of characteristics that distinguish it from coal. In addition, gas combustion can be said to be the most ideal combustion process, which is in terms of stoichiometry or the perfection of combustion compared to combustion of liquid or solid fuels. Large particle size such as coal will also have an effect on combustion and also make a fuel more difficult to burn. So that from this comparison, the industry can get an overview of the burning of the PKS and the scheme below to describe the case.

With adequate analysis, planning and system design, the use of new fuels, especially biomass, such as wood chips, wood pellets, wood briquettes and PKS can be implemented properly. Energy prices and environmental regulations are driving forces for the use of this new fuel. Fixed bed combustion type furnaces are most commonly used in a number of industries. These furnace variants include grate furnace types namely traveling grate, fixed grate system, incline moving grate & horizontally moving grate, vibrating grate, cigar burner and underfeed rotating grate, while other types are underfeed stokers. Meanwhile, the fluidized bed and pulverized combustion types are generally used by power plants. The technical considerations for selecting biomass-based solid fuels include heating value, moisture content, ash content, density, particle size, emissions, availability of these fuels, and suitability for the furnace. In the end, the most optimal combustion rate that is safe and meets environmental standards is the purpose of using the biomass fuel.

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.

Complete Feed Production With Integration of Energy Plantations and Community Empowerment

Feed and markets are the two most important things in the world of livestock. Farmers who are able to get safe, nutritious, affordable, adequate and sustainable feed will produce the best quality and quantity. One of the safe categories is not GMO. For more details, you can read it here. It is possible to make these feeds yourself by utilizing the local potential. The expertise to provide feed is of course very important for professional farms. Likewise, broad market access allows the livestock business to be increasingly profitable. The current era of the internet is also very supportive of gaining such broad market access. Social media such as whatsapp groups, telegram, twitter, youtube and so on can be used for this.

To get complete nutrition so that it becomes a complete feed, of course, cannot be obtained from just one source. Malnutrition which results in decreased quality and livestock production will inevitably occur, if the feed nutrition is inadequate. It is possible that the development of an energy plantation or a biomass plantation with leguminoceae plants such as gliricidia and red calliandra is very likely to be integrated with the livestock business. Sheep, goat and cow farms are the best choices for this farming business. It is also hoped that later progress in the renewable energy sector from energy or biomaterial plantations will be in line with the livestock business. While glicidia leaves or calliandra have the main content in the form of protein which can reach 25%, other sources of nutrients such as sources of fiber, vitamins and minerals can be obtained from the environment around the plantation. Communities around the plantation area can be empowered to plant these nutritional complementary crops or take advantage of their various agricultural wastes such as straw, grass and so on. 

The leaves of gliricidia or calliandra as a source of feed are estimated to be a maximum of 30% of the complete feed. With leaf productivity per hectare of around 30 tonnes / wet year or 18 tonnes / dry year. This means that for every 1000 hectares of gliricidia plantation will produce 18,000 tons / year of dry leaves. If a goat / sheep eats 3 kg / day (30% of the total consumption of complete feed), it means that for 1 year 1 sheep / goat consumes about 1 ton of dry leaves or with a volume of 18,000 tons / year means that it can be sufficient for 18,000 sheep / goats for 1 year.

The animal feed innovation must also be carried out so that the conversion of feed to meat product, milk or breed is high, even the feed formulation should be adjusted to the age level of the livestock. Researches to obtain varied feed formulations or recipes, especially those that are adaptive to local potential, are very important. This includes identifying and developing as many feed sources as possible. The more identified feed sources and feed formulations, it is hoped that the livestock business will grow rapidly. Case studies on gliricidia and calliandra leaves have several anti-nutritional substances, so these substances must also be reduced or even completely eliminated so that the feed nutrients are absorbed effectively. Anti-nutritional substances in gliricidia are dicoumerol, HCN (cyanide acid) and nitrates, while red calliandra is an anti-nutritional substance of tannins. 

Charcoal Production from Acacia Wood Stumps

After the acacia trees are cut down for paper production, a lot of wood waste is still not being utilized, including the stumps of the trees. Only the logs used for paper production have a diameter of 8 cm above, while the diameter is smaller as wood waste. After the trees are cut down, replanting is carried out and the wood stumps are left just like that. In fact, there are a lot of wood stumps, especially with an area of tens to hundreds of thousands of hectares of acacia forest. If every one hectare is produced 16 tons of acacia wood stumps, then with an area of 20,000 hectares, 320,000 tons of acacia wood stumps will be produced.

There is a difference in the handling of acacia or eucalyptus stumps and energy plantation stumps. On acacia or eucalyptus stumps, after the trees are cut, they have to replant again because their main target is wood products with a certain diameter, namely 8 cm and above. If the wood stump is grown again, it will take a very long time to reach that diameter, so it is not efficient. That is the reason for them to replanting after being cut down. Meanwhile, in energy plantation wood, after the trees are cut down, the remaining stumps are allowed to grow again. The main target of energy plantations is to achieve the highest volume of wood productivity in mass basis. Even after being felled, the number of branches that come out of the energy plantation stumps increases so that the productivity is also high. Apart from being able to be harvested repeatedly without having to replanting each time, productivity remains high because of the large number of coppices or branches, even four times the first harvest. 

The huge volume of acacia stumps is very potential for charcoal production. Acacia plantation companies can create jobs by empowering local communities to take and collect the acacia stumps. The acacia stumps are then processed into charcoal. With proven carbonization technology and high capacity, all of these stumps can be processed and have economic value. With the large volume of acacia stump waste, charcoal production can also be sustainable, just like the production of acacia wood from the acacia forest. Creating large and sustainable employment opportunities is a positive effort that is in line with bioeconomy and community welfare. The wood charcoal produced with this technology is also of high quality, even with a fixed carbon of more than 82% exceeding the European standard NF EN 1860-2.

Will the Materials for Paper Production Compete with Bioenergy?

Paper and bioenergy production, especially wood pellets, use the same raw material, namely wood. Currently, most of the wood pellets in Indonesia and Southeast Asia still use wood wastes such as sawdust as a source of raw material, while paper mills use wood from their own plantations such as acacia forests. With this condition alone, the raw materials for the two types of industries have different paths so that there is no competition. Even the paper industry only uses wood with a large diameter of 8 cm and above so that wood with a small diameter of less than 8 cm can be used for bioenergy production such as charcoal, wood pellets or wood briquette.

The need for paper appear not to have increased much so that paper production tends to be stable, even decreasing. This happened because of the era of information technology so that the use of paper was replaced by electronic media, the use of recycled paper and the recent pandemic conditions. This of course makes the use of wood as a raw material for paper tends to be stable or even reduced. In contrast to bioenergy, especially wood pellets, with the increasing number of biomass, especially wood as renewable energy, the need continues to increase. But the quality of wood needed for wood pellets is also lower than the quality of wood for paper production. The extent of land in Indonesia is also very possible for the production of wood pellets from energy plantations. Indonesia's wood pellet production is currently still small, which is estimated at less than 200 thousand tons per year.

Wood pellet production always uses wood waste or wood worth as wood waste. Log from energy plantations such as calliandra and gliricidia is cheap wood worth the wood waste so that it can be used for the production of the wood pellets. The high productivity of wood is the main goal for this energy plantation, even the energy plantation relies on coppice to maximize wood production from energy plantations. Another advantage of energy plantations or biomass plantations is that they can be integrated with livestock businesses, for more details, please read here. Whereas wood for paper production always uses gardens or timber forests such as acacia or eucalyptus. This is what makes the material needs for paper and bioenergy, especially wood pellets, not compete with each other. Whereas in countries like Canada that use the same type of wood, namely pine for paper and wood pellet production, indeed when a drastic increase for wood pellets, competition for wood with raw materials for paper is inevitable. Canada is currently one of the world's top producers of wood pellets with a production capacity of 3.9 million tons per year.