Biochar to Increase the Porosity of Damaged and Marginal Soils

Basically, porous materials will have large surface areas. The more pores, the greater the surface area of the material. Efforts to increase pores or expand the surface can be done in many ways depending on the goal. The type of pores also affects the total surface area and also the use or application of the material. For example, materials that have more micropores will have a larger surface area and have different specific uses than materials that are dominant with medium pores (mesopores) or large pores (macropores). Designing a material so that it is micropore, mesopore or macropore dominant can be done, namely by selecting raw materials and process technology, for example biochar produced from pyrolysis will produce a larger surface area compared to the initial unprocessed biomass.

In land related to use for agriculture or plant cultivation, the aspect of soil porosity or pores is an important aspect. This is mainly related to nutrient and water retention as well as soil aeration. Expanding soil pores will be very useful for improving soil quality so as to support the success of agriculture or plant cultivation. Soil that has more pore space will be able to store large amounts of water and nutrients too. Soil that has a high number of small (micropore) and medium (mesopore) pores will tend to hold water and nutrients more strongly than soil that has many large pores (macropore). And if there is evaporation or use of water by plants or a leaching process occurs in nutrients, then the large pores (macropores) left behind by the water and nutrients will follow the medium (mesopore) and  micropore.

Providing organic material in the form of compost to the soil is generally used to form more micropore spaces. The more micropore spaces that are formed, the more moisture the soil will have. Soil organic matter has more pores than soil mineral particles, which means that the surface area for absorption is also greater. Providing organic material in the form of compost, apart from increasing the number of pores or soil porosity, also reduces the volume weight. This organic material or compost is a source of energy for soil microbial activity, reduces soil volume, improves soil structure, aeration and air binding capacity. Soil with high total pores, such as clay, tends to have a low volume weight, while soil with low total pores, such as sandy soil (coarse texture), tends to have a high volume weight.

Apart from increasing total pores, adding compost also increases soil pH, namely in sandy soil and acidic soil, including entisol, ultisol and andisol and is able to reduce soil exchangeable Al. The increase in pH is due to the process of breaking down the compost. The results of this overhaul will produce basic cations which can increase the pH or release basic cations from the compost into the soil so that the soil is saturated with basic cations. The weathering or decomposition process of the compost will release alkaline cations which cause the soil pH to increase.

Soil organic C will also increase with the addition of compost and total N (nitrogen). The more organic matter added to the soil, the greater the increase in organic C in the soil. Compost from animal waste has the lowest C/N ratio compared to compost from plants. Organic materials that have a high lignin content will inhibit the speed of N mineralization and the C/N ratio will be high. In fact, further decomposition of organic matter is characterized by a low C/N ratio. Meanwhile, a high C/N ratio indicates that decomposition has not yet continued or has just started. In this process there is a decrease in carbon / C and an increase in nitrogen / N.

The need for compost on marginal land such as sandy land is also much greater, reaching almost twice as much as on ordinary or standard land. Meanwhile, the need for chemical fertilizer on marginal land is usually less than on normal/standard land. Ideally, using compost at optimal doses will be able to increase plant productivity and preserve the environment.

Unlike compost which will completely decompose, as a soil amendment, biochar can last hundreds of years in the soil. Biochar, which has a large surface area, also has many micropores which increase soil porosity, like compost. Pyrolysis conditions are important in determining the quality of biochar besides the biochar raw material itself. In rough textured soils such as sandy land, biochar will improve water and nutrient retention because its micro pores slow down its release (slow velocity). The quality of biochar is directly proportional to the efficacy of biochar treatment. A number of parameters related to the application of biochar for soil improvement/treatment are also similar to compost, including: soil carbon content and mineralization, soil micro-structural & aggregation, bioavailable nitrogen, and microbial activity & diversity. Almost all biochar is not fertilizer like compost, read more details here, so inoculation (charging) of biochar before application can be done by filling the biochar pores with water containing specific chemical elements or microbes. This will produce rapid positive effects compared to biochar alone. Apart from that, biochar is also used to reduce carbon dioxide (CO2) in the atmosphere as carbon sequestration. This is very much in line with the current problems of climate change and global warming.

Biochar is a heterogeneous substance rich in aromatic carbon and minerals. Biochar is produced from the pyrolysis process (a process where organic material is decomposed at temperatures between 350 to 1000 C with well-controlled conditions of minimal or no oxygen and is widely used for soil amendment). The carbon content for biochar must be above 50%, whereas if pyrolysis products of organic material with a carbon content of less than 50% are not included in the biochar category but are referred to as pyrogenic carbonaceous material (PCM). The organic carbon content of pyrolyzed char fluctuates between the range of 5% and 95%, depending on the raw material and temperature. process used. For example, the carbon content from pyrolysis of chicken manure is around 25%, while from wood it is around 85% and bone is less than 10%. When using mineral-rich raw materials such as sewage sludge or animal waste, the pyrolysis products will contain high ash so that the total pores are smaller.

Apart from that, biochar must also have a molar ratio of H/Corg of less than 0.7 and a molar ratio of O/Corg must be less than 0.4. The molar ratio of H/Corg is an indicator of its degree of carbonization (pyrolysis) and is therefore closely related to the stability of biochar, which is one of the most important characteristics of biochar. This ratio fluctuates depending on the type of biomass used and the conditions of the production process. A ratio value that exceeds 0.7 indicates non-pyrolytic char or inadequate pyrolysis process conditions. Meanwhile, the O/Corg ratio is also used to differentiate it from other carbon products. Specific surface area is also a measure of the quality and characteristics of biochar, and also a control value for the pyrolysis method used. Although a surface area of less than 150 m2/gram can be used in certain cases, it is preferred or preferred if it is more than 150 m2/gram.

With the characteristics above, compost and biochar as well as chemical fertilizers can be used together, even in the composting process biochar can also be added to reduce N organic released into the atmosphere. Apart from increasing the number of micro pores in the soil or increasing the total pores, the nutrients from compost and chemical fertilizers will also be released more slowly (slow release). How slow release the fertilizer can be designed depends on needs, for more details you can read here. When biochar is used properly, it can maximize harvest productivity, improve soil fertility and minimize environmental impacts. Four things need to be considered when applying biochar, namely the right source of biochar, the right location (right place), the right dose (right rate) and the right time. Not all types of soil and plants will produce increased yields from biochar applications, so it is important to know what type of soil produces increased productivity. A soil map can help to identify soil types that have the potential to provide benefits or advantages from the application of biochar. Farmers can consult with agricultural consultants or professionals in the field to help with the selection and application of biochar. 

Biochar and Specific Organic Fertilizer for Post-Mining Reclamation Treatment

Mining activities are not just digging, loading and transporting, but environmental sustainability is also an important thing that must be considered. Even post-reclamation has become an obligation for mining companies with severe sanctions if neglected. Environmental damage due to mining if left unchecked will become a serious environmental problem such as natural disasters, and become a bad legacy for future generations. This means that post-mining reclamation must be carried out properly or adequately so that the negative impact on the environment can be minimized or even eliminated. Reclamation planning and implementation needs to be done well so that the reclamation goals can be achieved.

Low fertility on post-mining land is indeed a separate problem for revegetating the land. When a mining company has good management of overburden (OB) and top soil so that it can be returned (backfill) to the former mining pit (void) as before, the decline in soil fertility can be minimized. But if the management is bad, the fertility of the soil will drop drastically or be severely damaged so that in these conditions certain treatments need to be carried out to restore, improve or increase the fertility of the soil. The condition of land that has low fertility or is like barren land is almost the same as sandy land. In general, coastal sandy land has the following characteristics: sandy soil texture (90%), granular soil structure, loose consistency, low nutrient content, low soil ability to store nutrients, very fast permeability, drainage and infiltration, porous (majority with mesopores and macropores, and less of micropores), low water holding capacity, low soil ability to support plant growth and relatively high salt content or is a marginal land for agriculture or plant cultivation, so the treatment approach on sandy land with post-mining land is an effort effective approach.

Agriculture or cultivation of sandy land can be done for both seasonal and annual crops, the same goes for post-mining land. Factors of effectiveness and efficiency need to be done to get optimal results such as the type of nutrient and its amount, water requirement and so on. Conditioning the land so that it can hold water and nutrients must be done so that the added fertilizer can be utilized properly. Minimum input so that production costs can be reduced or economic factors are other important things. With post-mining land areas that can reach thousands of hectares, the input in the form of quality fertilizer is a must. In addition to inorganic fertilizers as macro elements, organic fertilizers as a provider of micro elements also need to be added. Specific organic fertilizer according to land conditions and plant needs can be made for this purpose. The use of compost with volumes ranging from 20-30 tons/hectare can be significantly reduced by using this specific organic fertilizer.

Sandy soils generally have high P and K content. The function of organic matter, in this case manure, can stimulate the availability of P nutrients that have accumulated in the sandy soil in the form of total P, so that available P becomes greater. With the availability of P, the available K is also greater, because P interacts with K. Amelioration technology to increase soil fertility is needed. Amelioration itself is an effort to improve soil fertility through the addition of certain materials. Amelioran is a substance that can increase soil fertility by improving physical and chemical conditions. Biochar as a soil amendment will be effective for this purpose, even when compared to other soil amendments, biochar has many advantages, one of which is being able to last or not decompose in the soil for hundreds of years. While increasing the efficiency of using biochar is by designing slow release fertilizer (SRF) so that the release of fertilizer is according to plant needs or can be used by plants optimally.

Plants are composed of 92 elements, but only 16 are essential for their growth and development. Of the 16 elements, elements C, H, and O are obtained from air and water (in the form of CO2 and H2O), while 13 other essential mineral elements are obtained from the soil and are generally classified as "nutrients". There are 6 macro nutrients namely N, P, K, S, Ca and Mg. These macro elements are needed by plants in large quantities with a critical content (value) between 2 – 30 g/kg dry weight of plants. These macro nutrients are divided into two, namely primary nutrients (N, P, K) and secondary nutrients (S, Ca, Mg). Primary nutrients are provided in the form of all types of plants and all types of soil. Meanwhile, secondary nutrients are only for certain types of plants and certain types of soil. While micro nutrients consist of 7 elements consisting of 5 elements which are metals namely Fe, Mn, Zn, Cu and Mo, and 2 non-metallic elements namely Cl and B. The need for micro nutrients is relatively small ranging from 0.3 – 50 mg/kg dry plant weight. The combination of macro fertilizers and specific organic fertilizers will maximize plant growth.

Chemical Fertilizer Plant, Blue Hydrogen, Blue Ammonia and Ruminant Farms

As a comparison of the sheep population in New Zealand with people population of 3 million, the number of sheep is 5 million, then Australia with people population of 25 million, the total population of cattle is 26 million while Indonesia with people population of 270 million, the total population of sheep is less than 50 million, moreover the cattle population is also confirmed much smaller. This indicates that the ruminant livestock sector is not yet a business or industrial engine for economic growth. Whereas in addition to natural resources that support, the need for meat and fertilizer needs for agriculture is also very large. When the ruminant livestock sector is optimized, apart from being self-sufficient in meat as a source of animal protein, it can even be exported, and it will also promote agriculture because the manure is turned into organic fertilizer. This organic fertilizer has many advantages over chemical fertilizers, including not destroying the physical and chemical properties of the soil, activating soil microbes and providing complete nutrients. When the livestock sector is optimized, it is also very likely that it will replace the use of chemical fertilizers or other languages ​​as well as self-sufficiency in fertilizers so that chemical fertilizer plants close or stop producing. The integration of livestock and agriculture will create food sovereignty, an extraordinary achievement if it can be realized.

To save the chemical fertilizer plants, it can be converted into a plant or energy producer in the form of blue hydrogen or blue ammonia. Natural gas, which is a fossil fuel and is the raw material for chemical fertilizers, is separated from the carbon elements so that hydrogen is obtained. Carbon dioxide (CO2) gas that has been separated from natural gas is then captured and stored (CCS = Carbon Capture and Storage) so that it is not released into the atmosphere. And because the raw material for hydrogen fuel comes from fossil fuels, it is called blue hydrogen, whereas if it comes from renewable materials such as biomass, water and so on, it is called green hydrogen. So it can be said that blue hydrogen is still half fossil because the raw materials are from fossil sources and green hydrogen is already 100% from renewable sources. Hydrogen compounds or hydrogen gas have atomic bonds in the form of two hydrogen elements (H2) as a stable compound in nature, and to increase the energy of hydrogen gas, ammonia (NH3) can be made, namely with three hydrogen bonds. Just like the term blue hydrogen above, when the ammonia comes from fossil fuels it is called blue ammonia and when it comes from renewable materials it is called green ammonia. Japanese companies have even made power plants (generators) that use 100% as fuel, for more details read here.

Efforts to boost the livestock sector by integrating with the agricultural sector is not an easy thing. The factors of market access ability, farming techniques, provision of feed, management and livestock business are a number of things that hinder the realization of the vision of food sovereignty. Especially for innovations so that they can be competitive at the international level. Motivation factors, low willingness, low reading and learning culture, lack of friendship for networking, government alignments with policies for less carrying capacity, and so on also hinder on the other hand. But with abundant natural resources potential and strong will, these obstacles should be overcome, especially ruminant farming, especially sheep and goats, is also highly recommended in Islam so that as a Muslim should be more motivated. There is almost no one when doing any kind of effort, let alone to realize a big idea without a hitch, because that is the sunatullah.

Production of LOF and EFB Pellets at The Same Time

The leaching process for palm oil empty fruit bunches (EFB) so that it has potassium and chlorine content suitable for EFB pelletproduction on a commercial scale that can be used maximally on a pulverized combustion (PC) boiler at a power plant is not easy and inexpensive. That is because the leaching process requires a solvent to extract the potassium and chlorine content from the EFB material. Ideally the leaching process is carried out with acid solvents, agitation and heat and a long time so the extraction process can run optimally. In fact this is the bottle neck to carry out the leaching process, so that almost no one has done this process commercially today. It is different if the leaching process also has other objectives that also have commercial value, for example for the production of liquid organic fertilizer (LOF).

By simultaneously producing LOF, the costs for leaching can be compensated with the benefits of the LOF. In CPO business operations, especially in palm oil plantations the cost of fertilizer is one of the highest cost components, estimated at 35.75 billion rupiahs (around 2.5 million USD) per year for every 10,000 hectares. If the cost of the fertilizer can be saved from the use of self-produced LOF as well as pellet EFB production, then this is one of the optimization of biomass utilization in the palm oil industry. LOF will have the main content in the form of potassium because the potassium content is quite high at EFB about 30% of the ash produced is potassium. Potassium fertilizer is very beneficial for plants because it is an essential nutrient with benefits including transporting sugar, controlling stomata in leaves by maintaining electro-neutrality in plant cells, co-factor of more than 40 enzymes and reducing the occurrence of various diseases. Some plantations also need large amounts of potassium fertilizer, for example banana plantations. The process of making LOF by soaking EFB for several days is expected to significantly reduce the potassium and chlorine content in EFB and make it a material for pellets that are friendly to the PC boiler power plant.

The EFB pellets produced can then be sold for export as well as meeting domestic needs. With EFB pellet production as well as LOF, it is hoped that export bioenergy will not damage or reduce the fertility of the existing soil, something that is sometimes indeed dilemmatic. In addition, other materials in the plantation such as leaves and frond can still be composted if they are also intended as fertilizer. EFB pellet production also always requires energy in the form of electricity for its plant operations. And for that electricity can be produced from biogas by treating the palm oil mill effluent (POME), for more details, read here. The location of palm oil mills which are generally remote are required to be able to produce their own electricity, including if they are going to process EFB into LOF and EFB pellets, the electricity needs should also be fulfilled by themselves.

EFB pellets without leaching process actually can also be used for FBC (fluidized bed combustion) boiler technology and for a limited number percentage of PC boilers. With this leaching process EFB pellets can be used optimally on the PC boiler. Majority of power plants or coal power plants currently use PC boiler technology. So that if the EFB pellet produced can be friendly with a PC boiler the market is more open automatically. Production of EFB pellets which are agricultural waste pellets will usually be the second priority after the production of wood pellets is constrained mainly in terms of the availability and supply of raw materials.