Indonesia National Standard (SNI) of Biomass Pellet and Energy Plantation

Indonesia National Standard (SNI) for Indonesian biomass pellet products has been out and officially used since the end of 2020 or last year. The main objective of implementing SNI for biomass pellets is to respond to the cofiring program at PLN's (state owned electricity company) coal power plants. With this cofiring program, renewable fuels, especially biomass pellets, are used as the main fuel mixture, namely coal. The ratio of the use of renewable fuels in the form of biomass is still small, namely around 1-5% or the equivalent of 9-12 million tons / year of biomass fuel. The total coal power plants as a cofiring target is 114 units spread across 52 locations with a total capacity of 18,154 MW with the target to be completed in 2024. Almost all of the biomass pellets in Indonesia today are wood pellets, all of which also use wastes. sawmills or wood processing industries. In other terms, if you refer to wood pellets, then it must be biomass pellets, whereas if you refer to the term biomass pellets, this is not necessarily wood pellets, but it could be pellets from agricultural wastes (agro-waste pellets). Agricultural wastes which are abundant in Indonesia are also potential as raw material for biomass pellets such as rice husks, empty fruit bunches of palm oil, coconut husk and so on. Below is the table for the SNI biomass pellets:

 

Energy plantations can be a source of woody biomass specifically designed for energy production or specifically for raw materials for the production of biomass pellets or wood pellets. With energy plantations, large production capacities and guaranteed good supply can be achieved. The production of wood pellets from energy plantations takes longer because it needs to prepare and make the energy plantations and wait several years for the wood to be ready to harvest and be processed further into wood pellets. Calliandra and gliricidia are two species of fast rotation and coppice which have been chosen because of their superiority. Another thing that is very important to note is the high heating value and high productivity of wood per hectare. But there is a slight drawback of this type of wood is the content of potassium in ash which is quite high. This makes its use more limited, especially power plants with pulverized combustion (PC) technology.

 

Based on an experiment conducted with calliandra wood from the slopes of Merapi mountain, Central Java; Bangkalan, Madura and Aceh, Sumatera have an average potassium content of above 1000 ppm (0.1%). Indeed, the characteristics of fast-rotating crops tend to produce wood with higher levels of potassium. Meanwhile, from fruit plants, banana trees also have a high potassium content. This potassium has a low melting point and causes fouling in the heat exchanger pipes, thereby reducing the efficiency of the power plant. While chlorine compounds are other compounds that also need attention because they are corrosive at high temperatures, for more details, please read here. And in general, there are significant differences in ash chemistry between biomass and coal. But with a cofiring ratio of 1-5%, power plants generally do not modify their equipment or more specifically on PCs that are most sensitive to ash chemistry problems, because the cofiring percentage is still low.

 

With an average level above 1,000 ppm (0.1%) and still far from 50,000 ppm (5%), there is no problem for wood from energy plantations to be produced into wood pellets and supply to the coal power plants in Indonesia according to SNI the. But if it is exported to foreign countries, especially Japan and Korea, the circulating fluidized bed (CFB) and stoker type power plants are the best market share and the PC type is more limited. With the vast land available and Indonesia's tropical climate, it must further promote energy plantations both to meet domestic needs and to export markets. The energy plantation program also indirectly encourages the ruminant livestock sector, because the leaves can be used as animal feed.