Maximizing the Rate of CO2 Absorption from the Atmosphere Based on Biomass

Maximizing the rate of CO2 absorption from the atmosphere is very important considering the rate of addition of CO2 concentration to the atmosphere is not comparable to the rate of CO2 absorption. This is what makes the CO2 concentration continue to increase. To balance this speed, a strategy is needed to increase the rate of CO2 absorption. The use of biomass will be very effective and provide multiple benefits for human life. 

CO2 from the atmosphere needs to be captured through biomass production through the process of photosynthesis in plants. Fast-growing species of plants that have high photosynthesis rates are needed for this. Furthermore, biomass, especially wood from fast-growing species of plants, is used as raw material for biochar. Furthermore, biochar is used to improve soil fertility (soil amendment) in various types of agricultural and forestry plants.

Biochar production with slow pyrolysis will also produce excess heat, syngas and biooil that can be used as energy sources. The benefits of biochar production will be obtained from the sale of biochar, the sale of carbon credits and the use of slow pyrolysis by-products. With conditions like this, efforts to increase the speed of CO2 absorption from the atmosphere should be increased. How fast and how much CO2 volume can be absorbed will depend on the type of fast growing species used, the area of ​​planting and the capacity of biochar production.

Biochar or Biocoal Production?

Biochar and biocoal production are basically one breath. Biochar production with full pyrolysis while biocoal with half/mild pyrolysis (torrefaction). The purpose of torrefaction/mild pyrolysis is to increase its energy content and make it hydrophobic so it is called biocoal. While the purpose of full pyrolysis is to produce stable biocarbon material so that it does not decompose in the soil for hundreds or even thousands of years and improve soil fertility so as to increase plant productivity (agriculture and forestry). 

Current biochar applications are mainly for agriculture and biochar production will produce excess heat, syngas and biooil as energy sources. While biocoal only focuses on energy. The benefits of biochar production are obtained from the sale of biochar, the sale of carbon credits and the utilization of by-products (full) pyrolysis. While the benefits of biocoal are only from the sale of biocoal itself.

The selection or development of a business will be related to business readiness (market, technology, investment, etc.) and other benefits, namely benefits in the social and environmental sectors.

Charcoal Production for Activated Carbon Raw Material

Charcoal characteristics are influenced by the raw materials used and the conditions of the production process. The use of charcoal for certain applications or industries also requires certain specifications or characteristics. For example, charcoal used for fuel can have different specification requirements from charcoal specifications for agriculture (biochar), or charcoal used as raw material for activated carbon. A number of parameters that are acceptable in certain applications may not be acceptable in other applications.

Charcoal products used as raw materials for activated carbon production are also the same. Parameters in the form of high fixed carbon (~80%), high hardness, low ash content (~3%) and low volatile matter (<10%) are prerequisites for the specifications or quality of charcoal as a raw material for activated carbon. As a comparison, charcoal for agriculture (soil amendment) or commonly called biochar has a wide range of quality or specifications, namely lower fixed carbon (FC), higher ash content and higher volatile matter, especially in agro type biochar according to WBC (World Biochar Certificate), while premium type biochar according to WBC has a higher or highest quality and can be used for various purposes. While the material type biochar according to WBC has the lowest quality with use mainly in certain industries such as cement, asphalt, plastic, electronics, and composite materials or cannot be used for agriculture, soil applications and consumer products.

Raw materials for charcoal production for activated carbon production because it requires stricter parameters, especially high fixed carbon, low ash content and high hardness so that raw materials suitable for this purpose are more limited or not all biomass can be used for charcoal production for activated carbon raw materials. This is what makes coconut shells the best and most popular raw material for charcoal production as activated carbon raw materials today. And palm kernel shell raw materials (especially from dura variety) are expected to be the next candidate. The availability of abundant palm kernel shells (PKS) is a special attraction. But indeed with this palm kernel shell (PKS) charcoal raw material, there is still the smell of palm oil, so it is a challenge for activated carbon producers.

Biochar For Patchouli Plantation

Indonesia is famous for producing various essential oils, including patchouli oil, clove leaf oil and so on. The main use of essential oils is mainly for food, pharmaceuticals, fragrances (perfumes). The potential of this country to develop essential oils is very large due to climate factors, land area and soil fertility. World export-import statistics data show that consumption of essential oils and their derivatives has increased by around 10% from year to year. Of the 70 types of essential oils traded on the international market, citronella oil, patchouli, vetiver, ylang-ylang, cloves, pepper, and jasmine oils are supplied from Indonesia. Indonesia is the largest country in Southeast Asia producing essential oils and is among the top 10 in the world.

Patchouli production centers in Indonesia are in Bengkulu, West Sumatra, and Nangro Aceh Darussalam. The quality of Indonesian patchouli oil is known to be the best and controls 80-90% of the world's market share or the largest supplier of patchouli oil in the world. This patchouli oil comes from the distillation of dried leaves to extract the oil which is widely used in various industrial activities. Patchouli oil is used as a fixative or binder for other fragrance ingredients in perfume and cosmetic compositions. The area of patchouli planting reaches 21,716 ha spread across 11 provinces in Indonesia, and in 2008 about 2,500 tons of patchouli oil were produced.

Patchouli plants commonly cultivated in Indonesia are Aceh patchouli because the oil content is > 2% and the oil quality is patchouli alcohol (PA) > 30% higher than Java patchouli which has an oil content of <2%. Furthermore, with Aceh patchouli, there are three varieties of patchouli plants found in Aceh, namely Tapaktuan patchouli, Lhokseumawe patchouli, Sidikalang patchouli. The PA levels of the three varieties vary, namely: Tapaktuan (28.69-35.90%), Lhokseumawe (29.11-34.46%), and Sidikalang (30.21-35.20%).

Patchouli Oil Production in Sentra Province 2015-2020**)

One of the factors that support plant growth and optimal production is the availability of sufficient nutrients in the soil. The level of nutrient availability for patchouli plants must be optimal to obtain high growth and oil content. Patchouli is known to be very greedy for nutrients, especially nitrogen (N), phosphorus (P) and potassium (K). Patchouli plants are among those that require quite a lot of nutrients, so that production continues to run optimally, fertilizer application is carried out very seriously. This is so that the level of soil fertility must be maintained optimally if we expect optimal patchouli agricultural production. Therefore, in the shifting patchouli cultivation system, there will be a very rapid decrease in land fertility which will damage the land.

Patchouli can be cultivated on dry land, thus the development of patchouli plants is very relevant to the potential of dry land which is quite extensive in Indonesia compared to rice fields. In fact, dry land is the most widely distributed sub-optimal land, which is around 122.1 million ha consisting of 108.8 million ha of acidic dry land and 13.3 million ha of dry climate dry land. The development of patchouli plants has a dual purpose, in addition to increasing farmers' income, it also increases the productivity of dry land which is widely spread in Indonesia.

To improve land quality, namely by applying biochar. The application of biochar to agricultural land functions as a soil amendment that can improve the chemical properties of the soil (pH, cation exchange capacity, total N, and available P), the physical properties of the soil (bulk density, porosity and the ability of the soil to hold water). Improvement in the quality of the chemical and physical properties of the soil has an impact on the availability of nutrients and water through the ability of biochar to retain nutrients and water. Ultimately, the addition of biochar has implications for increasing the productivity of patchouli plants. In the future, it is hoped that with the application of biochar, more suboptimal and degraded lands which can be restored and plants productivity increased.

Optimizing the use of dry land for food crop cultivation needs to begin with land rehabilitation efforts so that plants can produce optimally. Soil amendments that are cheap, readily available and can last a long time in the soil are expected to be able to trigger the rate of increase in dry land productivity. The potential for agricultural waste to be converted into soil amendments (biochar) in Indonesia is quite large. Biochar applications have been proven to improve the quality of physical and chemical properties of the soil, as well as increase water availability. Crop productivity also increases in line with the recovery of land quality.

Biochar can also be added during composting so that more nitrogen (N) content can be absorbed in the biochar. The higher the nitrogen (N), the better the compost quality will be. Total N is one of the macro elements needed by plants in large quantities, accounting for 1.5% of the dry weight of the plant. Nitrogen is useful in the formation of protein, a component of plant chlorophyll, and if morphologically N plays a role in the formation of leaves and stems of plants or the vegetative formation of plants. Phosphorus is an absolute nutrient needed by plants after nitrogen. Symptoms of phosphorus (P) nutrient deficiency are seen as the color of the plant becomes dark green or purplish green which is then followed by older leaves turning purplish. The addition of biochar and compost, in addition to increasing the productivity of patchouli leaves, can even increase the yield of patchouli oil from an average of 2% to 4% and the patchouli alcohol content of patchouli oil from an average of 32% to 40%.