Biomass is being increasingly used in power plants in Japan as a source of fuel, particularly after the tragic accident at Fukushima nuclear power plant in 2011. Palm kernel shell (PKS) has emerged as a favorite choice of biomass-based power plants in the country. Most of these biomass power plants use PKS as their energy source, and only a few operate with wood pellets. Interestingly, most of the biomass power plants in Japan have been built after 2015.
Palm Kernel Shells
Palm Kernel Shell is generating very good traction as a renewable energy resource and biomass commodity in Japan. This is because PKS is the cheapest biomass fuel and is available in large quantities across Southeast Asia. PKS, a biomass waste generated by palm oil mills, can be found in plentiful quantities in Indonesia, Malaysia and Thailand.
PKS must meet the specifications before being exported to Japan. Some key specifications for PKS exports are: moisture content, calorific value and impurities or contaminants (foreign materials). All three variables must meet a certain level to achieve export quality. Japanese markets or their consumers generally require contaminants from 0.5 to 2%, while European consumers of PKS need 2% – 3%.
Japan usually buys with a volume of 10,000 tonnes per shipment, so PKS suppliers must prepare a sufficient stockpile of the PKS. The location of PKS stockpile that is closest to the seaport is the ideal condition to facilitate transportation of shipment.
PKS has emerged as an attractive biomass commodity in Japan
Wood pellets are mostly produced in from wood waste such as sawdust, wood shaving, plywood waste, forestry residues, and related materials while using tools like track saws, table saws, circular saws, miter saws, etc. The development potential for quantity enlargement is also possible with energy plantations. Technically the properties of wood pellets are not much different from the PKS.
Wood pellet price is more expensive than PKS. Wood pellet production process is more complex than PKS, so wood pellet is categorized as finished product. The quality of wood pellet is generally viewed from its density, calorific value and ash content. Indonesia wood pellet export is not as big as PKS, it is also because of the limited producers of wood pellet itself.
Japan buys wood pellets from Indonesia mostly for testing on their biomass power plants. Shipping or export by container is still common in wood pellet sector because the volume is still small. Currently, the world’s leading producer of wood pellets come from North America and Scandinavia. Even for Indonesia itself wood pellet is a new thing, so its production capacity is also not big.
For a short-term solution, exporting PKS is a profitable business. Wood pellets with raw materials from energy plantations by planting the legume types such as calliandra are medium-term solutions to meet biomass fuel needs in Japan. Torrefaction followed by densification can be a long-term orientation. Torrified pellet is superior to wood pellet because it can save transportation and facilitate handling, are hydrophobic and has higher calorific value.
There has been a flurry of activity in the biomass energy sector in recent year, with many new projects and initiatives being given the green light across the globe. This movement has been on both a regional and local level; thanks to the increased efficiency of biomass energy generators and a slight lowering in implementation costs, more businesses and even some homeowners are converting waste-to-energy systems or by installing biomass energy units.
Latest from the United Kingdom
Our first notable example of this comes from Cornwall in the UK. As of this week, a small hotel has entirely replaced its previous oil-based heating system with biomass boilers. Fuelled from wood wastes brought in from a neighboring forest, the BudockVean hotel has so far been successful in keeping the entire establishment warm on two small boilers despite it being the height of British winter – and when warmer weather arrives, plans to install solar panels on the building’s roof is to follow.
Similar projects have been undertaken across small businesses in Britain, including the south-coast city of Plymouth that has just been announced to house a 10MW biomass power plant (alongside a 20MW plant already in construction). These developments arein part thanks to the UK government’s Renewable Heat Incentive which was launched back in 2011. The scheme only provides funding to non-domestic properties currently, but a domestic scheme is in the works this year to help homeowners also move away from fossil fuels.
Initiatives (and Setbacks) in the US
Back across the pond, and the state of New York is also launching a similar scheme. The short-term plan is to increase public education on low-emission heating and persuade a number of large business to make the switch; in the longer term, $800m will be used to install advanced biomass systems in large, state-owned buildings.
A further $40m will be used as part of a competition to help create a series of standalone energy grids in small towns and rural areas, which is a scheme that could hopefully see adopted beyond New York if all goes well.
Unfortunately, the move away from fossil fuels hasn’t been totally plain sailing across the US. Georgia suffered a blow this week as plans to convert a 155MW coal plant to biomass have been abandoned, citing large overheads and low projected returns. The company behind the project have met similar difficulties at other sites, but as of this week are moving ahead with further plans to convert over 2000MW of oil and coal energy generation in the coming years.
Elsewhere in the US, a company has conducted a similar study as to whether biomass plant building will be feasible in both Florida and Louisiana. Surveying has only just been completed, but if things go better than the recent developments in Georgia, the plants will go a long way to converting biomass to fertilizer for widespread use in agriculture in both states.
Far East Leading the Way
One country that is performing particularly well in biomass energy investment market is Japan. Biomass is being increasingly used in power plants in Japan as a source of fuel, particularly after the tragic accident at Fukushima nuclear power plant in 2011. Palm kernel shell (PKS) has emerged as a favorite choice of biomass-based power plants in the country. Most of these biomass power plants use PKS as their energy source, and only a few operate with wood pellets. Interestingly, most of the biomass power plants in Japan have been built after 2015..
On the contrary, the US and Europe saw a fairly big fall in financing during this period; it should be noted, however, that this relates to the green energy investment market as a whole as opposed to biomass-specific funding. The increase seen in Japan has been attributed to an uptake in solar paneling, and if we look specifically to things such as the global demand for biomass pellets, we see that the most recent figures paint the overall market in a much more favorable light for the rest of the world.
Brighter Times Ahead
All in all, it’s an exciting time for the biomass industry despite the set backs which are being experienced in some regions. On the whole, legislators and businesses are working remarkably well together in order to pave the way forward – being a fairly new market (from a commercially viable sense at least), it has taken a little while to get the ball rolling, but expect to see it blossom quickly now that the idea of biomass is starting to take hold.
Europe is targeting an ambitious renewable energy program aimed at 20% renewable energy in the energy mix by 2020 with biomass energy being key renewable energy resource across the continent. However, the lack of locally-available biomass resources has hampered the progress of biomass energy industry in Europe as compared with solar and wind energy industries. The European biomass industry is largely dependent on wood pellets and crop residues.
Europe is the largest producer of wood pellets, which is currently estimated at 13.5 million tons per year while its consumption is 18.8 million tons per year. The biggest wood pellet producing countries in Europe are Germany and Sweden. Europe relies on America and Canada to meet its wood pellet requirements and there is an urgent need to explore alternative biomass resources. In recent years, palm kernel shells (popularly known as PKS) from Southeast Asia and Africa has emerged as an attractive biomass resources which can replace wood pellets in biomass power plants across Europe.
What are Palm Kernel Shells
Palm kernel shells are the shell fractions left after the nut has been removed after crushing in the Palm Oil Mill. Kernel shells are a fibrous material and can be easily handled in bulk directly from the product line to the end use. Large and small shell fractions are mixed with dust-like fractions and small fibres.
Moisture content in kernel shells is low compared to other biomass residues with different sources suggesting values between 11% and 13%. Palm kernel shells contain residues of Palm Oil, which accounts for its slightly higher heating value than average lignocellulosic biomass. Compared to other residues from the industry, it is a good quality biomass fuel with uniform size distribution, easy handling, easy crushing, and limited biological activity due to low moisture content.
Press fibre and shell generated by the palm oil mills are traditionally used as solid fuels for steam boilers. The steam generated is used to run turbines for electricity production. These two solid fuels alone are able to generate more than enough energy to meet the energy demands of a palm oil mill.
Advantages of Palm Kernel Shells
PKS has almost the same combustion characteristics as wood pellets, abundantly available are and are cheap. Indonesia and Malaysia are the two main producers of PKS. Indonesian oil palm plantations cover 12 million hectares in Indonesia and 5 million hectares in Malaysia, the number of PKS produced from both countries has exceeded 15 million tons per year. Infact, the quantity of PKS generated in both countries exceeds the production of wood pellets from the United States and Canada, or the two largest producers of wood pellets today.
Interestingly, United States and Canada cannot produce PKS, because they do not have oil palm plantations, but Indonesia and Malaysia can also produce wood pellets because they have large forests. The production of wood pellets in Indonesia and Malaysia is still small today, which is less than 1 million tons per year, but the production of PKS is much higher which can power biomass power plants across Europe and protect forests which are being cut down to produce wood pellets in North America and other parts of the world.
PKS as a Boiler Fuel
Although most power plants currently use pulverized coal boiler technology which reaches around 50% of the world’s electricity generation, the use of grate combustion boiler technology and fluidized bed boilers is also increasing. Pulverized coal boiler is mainly used for very large capacity plants (> 100 MW), while for ordinary medium capacity uses fluidized bed technology (between 20-100 MW) and for smaller capacity with combustor grate (<20 MW). The advantage of boiler combustion and fluidized bed technology is fuel flexibility including tolerance to particle size.
When the pulverized coal boiler requires a small particle size (1-2 cm) like sawdust so that it can be atomized on the pulverizer nozzle, the combustor grate and fluidized bed the particle size of gravel (max. 8 cm) can be accepted. Based on these conditions, palm kernel shells has a great opportunity to be used as a boiler fuel in large-scale power plants.
Use of PKS in pulverized coal boiler
There are several things that need to be considered for the use of PKS in pulverized coal boilers. The first thing that can be done is to reduce PKS particle size to a maximum of 2 cm so that it can be atomized in a pulverized system. The second thing to note is the percentage of PKS in coal, or the term cofiring. Unlike a grate and a fluidized bed combustion that can be flexible with various types of fuel, pulverized coal boilers use coal only. There are specific things that distinguish biomass and coal fuels, namely ash content and ash chemistry, both of which greatly influence the combustion characteristics in the pulverized system.
PKS has emerged as an attractive biomass commodity in Japan
Coal ash content is generally greater than biomass, and coal ash chemistry is very different from biomass ash chemistry. Biomass ash has lower inorganic content than coal, but the alkali content in biomass can change the properties of coal ash, especially aluminosilicate ash.
Biomass cofiring with coal in small portions for example 3-5% does not require modification of the pulverized coal power plant. For example, Shinci in Japan with a capacity of 2 x 1,000 MW of supercritical pulverized fuel with 3% cofiring requires 16,000 tons per year of biomass and no modification. Similarly, Korea Southeast Power (KOSEP) 5,000 MW with 5% cofiring requires 600,000 tons per year of biomass without modification.
PKS cofiring in coal-based power plants
Pulverized coal-based power plants are the predominant method of large-scale electricity production worldwide including Europe. If pulverised fuel power plants make a switch to co-firing of biomass fuels, it will make a huge impact on reducing coal usage, reducing carbon emissions and making a transition to renewable energy. Additionally, the cheapest and most effective way for big coal-based power plants to enter renewable energy sector is biomass cofiring. Palm kernel shells can be pyrolyzed to produce charcoal while coal will produce coke if it is pyrolyzed. Charcoal can be used for fuel, briquette production and activated charcoal.
Even though palm kernel shell has many similarities with wood pellets, it is not easy to reduce its size which makes it difficult for its optimum cofiring with coal in power plants and industries. Few years ago, Indonesia had exported PKS to Poland for cofiring purposes but because PKS was difficult to make powder (low grindability) it made cofiring performance poor, so the use of PKS for cofiring is currently discontinued.
To improve the quality of PKS, especially for the use of cofiring, PKS must be processed with torrefaction (mild pyrolysis). With the torrefaction process, it becomes easier to make powder from PKS, so that the desired particle size for cofiring is easier to obtain. Another advantage of the torrefaction process is that the caloric value of PKS will also increase by about 20%, Torrified biomass is hygroscopic which means ease in indoor as well as outdoor storage.
During the torrefaction process, PKS is heated at a temperature of around 230 to 300 °C in the absence of oxygen. With continuous pyrolysis technology, torrified PKS production can be carried out at large capacities. The need for biomass fuel for electricity generation is also large, usually requiring 10 thousand tons for each shipment. PKS torrified producers must be able to reach this capacity. The production of 10 thousand tons of PKS that are burned can be done per month or several months, for example, to reach 10 thousand tons it takes 2 months because the factory capacity is 5000 tons per month.
In general, the advantages of the PKS torrefaction process are as follows:
It increases the O/C ratio of the biomass, which improves its thermal process
It reduces power requirements for size reduction, and improves handling.
It offers cleaner-burning fuel with little acid in the smoke.
Torrefied PKS absorbs less moisture when stored.
One can produce superior-quality PKS pellets with higher volumetric energy density.
Pelletizing of torrefied PKS can be an option to increase the energy density in volume basis. The pelletizing process resolves some typical problems of biomass fuels: transport and storing costs are minimized, handling is improved, and the volumetric calorific value is increased. Pelletization may not increase the energy density on a mass basis, but it can increase the energy content of the fuel on a volume basis.
Africa, especially West Africa, which has many palm oil plantations and also the location where the palm oil trees originate, can supply torrified PKS to Europe to meet its rapidly-increasing biomass fuel demand.
In Africa, palm kernel shell is generally produced from PKO mills. CPO production is generally carried out on a small scale and only processes the fiber portion of the palm oil fruit. This palm oil mesocarp fibre is processed to produce CPO, while the nut that consist kernels and shells are processed elsewhere to produce the main product of PKO (palm kernel oil). PKO mills are usually quite large by collecting nuts from these small scale CPO producers. PKS is produced from this PKO mills.
The nut cracker machine separates kernel and shell
The distance between Africa and Europe is also closer than Europe to Malaysia and Indonesia. Currently, even though Europe has produced wood pellets for their renewable energy program to mitigate climate change and the environment, the numbers are still insufficient and they are importing wood pellets from the United States and Canada in large quantities. European wood pellet imports are estimated to reach more than 1.5 million tons per year. Torrified PKS from West Africa can help in meeting the biomass fuel demands for power plants across Europe.
Japan’s biomass fuel requirement is estimated to be tens of millions of tons each year on account of its projected biomass energy capacity of 6,000MW by the year 2030. To achieve this capacity, more than 20 million tons of biomass fuel will be needed every year which will be mainly met by wood pellets and palm kernel shell (PKS). The similarity of the properties of wood pellets with PKS makes PKS the main competitor of wood pellets in the international biomass fuel market.
PKS has emerged as an attractive biomass commodity in Japan
Canada and USA are the biggest suppliers of wood pellets to the Japanese biomass market while PKS mainly comes from Indonesia and Malaysia. With the size of the material almost the same as wood pellets, but at a cheaper price (almost half the wood pellets) and also available in abundance, PKS is the preferred biomass fuel for the Japanese market. PKS can be used 100% in power plants that use fluidized bed combustion technology, while wood pellets are used in pulverized combustion.
Although there is abundant PKS in CPO (crude palm oil) producing countries, but fluctuations in CPO production and increase in domestic demand has led to reduction in PKS exports in Southeast Asia. In palm oil plantations, it is known as the low crop season and peak crop season. When the low crop season usually occurs in the summer or dry season, the supply of fruit to the palm oil mills decreases so that the CPO production decreases and also the supply of PKS automatically reduces, and vice versa in the peak crop season. When demand is high or even stable but supply decreases, the price of PKS tends to rise.
In addition, a wide range of industries in Indonesia and Malaysia have also began to use PKS as an alternative fuel triggering increased domestic demand. In recent years, PKS is also being processed into solid biomass commodities such as torrified PKS, PKS charcoal and PKS activated carbon. Thus, there is very limited scope of increasing PKS supply from Southeast Asia to large-scale biomass consumers like Japan and South Korea.
Palm oil mills process palm oil fruit from palm oil plantations, so the more fruit is processed the greater the PKS produced and also more processors or mills are needed. At present it is estimated that there are more than 1500 palm oil mills in Indonesia and Malaysia. Palm kernel shells from Indonesia and Malaysia is either being exported or used domestically by various industries. On the other hand, in other parts of the world PKS is still considered a waste which tends to pollute the environment and has no economic value.
Top palm oil producers around the world
West African countries, such Nigeria, Ghana and Togo, are still struggling to find a sustainable business model for utilization of PKS. Keeping in view the tremendous PKS requirements in the Asia-Pacific region, major PKS producers in Africa have an attractive business opportunity to export this much-sought after biomass commodity to the Japan, South Korea and even Europe.
Simply speaking, PKS collected from palm oil mills is dried, cleaned and shipped to the destination country. PKS users have special specifications related to the quality of the biomass fuel used, so PKS needs to be processed before exporting.
PKS exports from Indonesia and Malaysia to Japan are usually with volume 10 thousand tons / shipment by bulk ship. The greater the volume of the ship or the more cargo the PKS are exported, the transportation costs will generally be cheaper. African countries are located quite far from the Asia-Pacific region may use larger vessels such as the Panamax vessel to export their PKS.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.