Cogeneration in Palm Oil Mills with Pyrolysis, Initial Steps in Biochar Production and Implementation

The analogy is like cofiring carried out in coal-fired power plants by mixing biomass fuels with a certain ratio as an effort to decarbonize the energy sector in power plants. While in palm oil mills, cogeneration with pyrolysis is an innovative initial step to enter the carbon negative era with the application of biochar, the main product of pyrolysis. And because all palm oil mills use biomass fuel for their mill operations, they are already based on carbon neutral fuel, unlike coal-fired power plants which are based on carbon positive fuels because they come from fossils.

Unlike cofiring which mixes coal and biomass fuels with a certain ratio and then burns them together in a furnace such as pulverized combustion, cogeneration is done by producing energy separately but the energy output is for the same use or especially the same boiler. This is done because the types of fuels may be different, such as solid fuels with liquid fuels or the technology for producing the energy is different. With this cogeneration, it means that not all energy is produced from one energy source or energy from cogeneration is a secondary energy source to meet total energy needs, and in the case of cogeneration in this palm oil mill, energy from combustion is still the primary energy.

Then why not just do full pyrolysis? It is easier, gradually for palm oil mills to adopt pyrolysis technology and its characteristics. Because (slow) pyrolysis aims to maximize solid / biochar, the by-products in the form of excess energy (syngas and biooil) as a source of boiler fuel, the calorific value is not as much as combustion which is indeed intended to maximize heat. Only about 1/3 of the excess energy contributes (cogeneration) as boiler fuel. In other words, if full pyrolysis is carried out directly, the amount of biomass as raw material for pyrolysis becomes 3 times greater or the pyrolysis unit becomes very large so that all palm oil mill biomass waste is used, and the mill cannot sell its palm kernel shells.

What are the benefits obtained by palm oil mills if they carry out cogeneration with pyrolysis for biochar production? Among the biochar products, it can save fertilizer use in oil palm plantations, overcome the problem of empty oil palm bunches (EFB) so that palm oil mills can achieve zero waste, palm kernel shells (PKS) that have been used for boiler fuel can be sold to increase income, the productivity of fresh fruit bunches (FFB) of palm oil increases, the application of biochar in palm oil plantations is also a climate solution (carbon sequestration / carbon sink) so that it can get carbon credit compensation and with good waste management, even zero waste and the application of biochar in palm oil plantations, palm oil companies will get a good image in terms of the environment and sustainability.  

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.

Fertilizer Savings in Palm Oil Plantations with Biochar and Compost from Biogas Waste

Although Indonesia is the largest CPO producer in the world with an area of ​​approximately 13 million hectares of palm oil plantations, but it is estimated that less than 10% have a biogas facility from POME (Palm oil mill effluent). Whereas by utilizing POME for biogas production, besides being able to be converted into electricity or heat, it also produces organic fertilizer in the form of compost and liquid organic fertilizer. The compost can be used as fertilizer in oil palm plantations, where the cost of fertilizer for palm oil operations is the highest cost component. It is estimated that every 10,000 hectares costs approximately Rp. 35.75 billion (around US$ 2.25 million) for fertilizer and for more details, you can read here. The use of compost will certainly reduce the need for fertilizer.

Palm oil utilization scheme for optimizing CPO production

Besides that, solid wastes such as palm oil empty fruit bunch, fiber and palm oil frond are also very potential for the production of energy (electricity and heat) and biochar. Energy production in the form of electricity and heat is by burning pyrolysis byproducts in the form of syngas and biooil into the furnace to heat the boiler. And because the syngas and liquid fuels used in the furnace, so that the combustion process is more perfect and clean emissions. Steam generated from the boiler will then drive the steam turbine and generator so as to produce electricity. Low pressure steam from steam turbine is then used for sterilization or boiling the fresh fruit bunches (FFB). While biochar will be used together with compost and chemical fertilizers to make fertilizer effective in the palm oil plantations so that it becomes a slow release fertilizer. Costs for fertilization are also expected to be significantly reduced, for example by up to 50% by this way. Although biochar is not a fertilizer, it has a function that makes fertilizer use effectively because it holds fertilizer nutrients from leaching, for example from rain water, also maintains moisture and so on.

PKS loading for export in Indonesia

PKS (palm kernel shell) can even be sold or exported. This is because previously or in general the palm kernel shells used to fuel boilers with fiber, have been substituted with products from the pyrolysis process namely syngas and biooil. The need for palm kernel shells for both the domestic / local and export markets continues to increase all the time. Palm kernel shells / PKS are environmentally friendly fuels because they come from biomass so they are carbon neutral fuels. The use of PKS as a fuel is widely used by a number of industries starting as a heat source for the drying process such as spray dryers in detergent and ceramic plants, boilers in food industries such as soy sauce factory, to power plants such as in Japan, can be read in more detail here. In the world of biomass fuel commodity trading, especially in the international market, PKS is the main competitor of wood pellets. Although the specifications are not much different, the price of PKS is also cheaper because it comes from palm oil mill waste and does not need complex processing units such as wood pellets. And basically with the scheme of utilizing palm oil mill wastes as above, it will maximize the profit from the palm oil mill or CPO mill.

Energy Independent With Pyrolysis

A community even in remote areas can be energy independent as long as there is an energy source in the area. Biomass energy sources from plants are energy sources that can be obtained almost anywhere. The plant can be planted as a source of raw materials for the production of energy needed. Heat and electricity energy is energy that mostly needed, in addition to energy or fuel for vehicles as a means of transportation. Heat energy is mainly needed for cooking while electrical energy for various purposes in life. Pyrolysis is a technology that can meet the energy needs as above. The diagram below explains the application of pyrolysis to meet these energy needs:

Charcoal is a solid fuel product from pyrolysis. Although solid fuels such as charcoal, are not as practical and easy as gas fuels, the use of charcoal for cooking fuel has many advantages including being safe because it will not explode, smokeless, odorless, has a high calorific value and is an environmentally friendly fuel. While firewood in addition to causing a lot of smoke, smell, low calorie value also interfere with health. Today there are also many countries in Africa that use charcoal for cooking fuel. To make it easier to use and store, the charcoal can be made into briquettes. While fuel for vehicles such as diesel oil and gasoline can be produced from biooil. Vehicles for transportation can operate in the presence of these fuels. The availability of petroleum in Indonesia, which is estimated to be 10 years away, needs to be anticipated and prepared from now on. The current low price of petroleum makes petroleum exports less attractive, especially for Indonesia, which is currently a net importer of petroleum.

Charcoal stoves are widely used in Africa

In the future era when electric vehicles are widely used, electricity production especially for battery charging is prioritized. The energy source for electric cars as environmentally friendly vehicles should also be from renewable energy sources, for more details, please read here. Biomass is a carbon neutral energy source so it does not increase the concentration of CO2 or greenhouse gases in the atmosphere. Woody biomass from the energy plantation is the ideal raw material for the pyrolysis feed. Multipurpose energy plantations are the best energy plantation for this, so that in addition to sustainable production, it also provides other benefits, for more details about multipurpose energy plantations can be read here. Remote areas, especially those with large lands, will have the potential to develop these energy plantations, so that an energy independent community or region can truly be formed and sustainable. Areas in surrounding the palm oil plantations can also utilize biomass waste from palm oil mills and plantations such as palm oil empty fruit bunches (EFB), fronds, etc. for the pyrolysis feed. Indonesia is the owner of the largest palm oil plantation in the world with an area of ​​around 13 million hectares and 1,000 palm oil mills. 

Syngas Cleaning And Operation Time For Private/Independent Power Providers (IPP)

The continuity and stability of the electricity supply to the buyer is the most important thing for the private power provider or the Independent Power Producer (IPP). Electrical buyers in general are government through PLN or industry. To be able to provide such a continuous and stable electricity supply, IPP strives in such a way in a variety of ways including its various process engineering and also the operational. Biomass is a renewable energy source for electricity production that has many advantages especially in Indonesia, for example when wind and water (hydro) power plants are severely affected by weather conditions, the biomass power plant is not affected. Even high rainfall and tropical climate will increase the production of biomass as a source of energy. Related to the use of gas from biomass there are two routes to produce gas that is biology route and thermochemical route. The biological route is by fermentation in the digester, while the thermal route with gasification and pyrolysis. The characteristics of the raw material will determine the choice of technology, whether by biological route or thermochemical. Liquid waste or high water content and easy rot, such as livestock manure and palm oil mill effluent (POME) will use biological route, whereas biomass which is not easy to decompose such as woody biomass thermochemical route becomes the choice.

Why need to extract gas from the biomass? This is in addition to improving efficiency, also facilitate the utilization. Even by extracting the gas will also produce a number of economic value-added byproducts, for example with pyrolysis technology in addition to generating electricity, by-products such as charcoal, biooil, and biomass vinegar (liquid smoke). The economic value of these byproducts are bigger than the electricity production. The gas composition of the various biomasses also varies, depending on the biomass and the technology used, for example in biogas of large methane gas composition (55-75%), gasification of methane gas composition 0.5-3% while in pyrolysis gas composition methane 4-11%. Gas engine is a equipment or device commonly used to convert the combustible gas into electricity. Gas turbine although efficiency is higher but rarely used because of operational and maintenance factors are more difficult. Steam turbine is also rarely used and commonly used in large capacity power plants (> 20 MW). While Stirling engine and ORC (Organic Rankine Cycle) technology can also use gas from the biomass, but it is not specific because both Stirling engine and ORC only require heat for its operation and it does not have to be from gas. Practically both technologies above are using a lot of combustion to obtain the required heat.

Stirling Engine

ORC Technology

Gas Turbine

Gas Engine

The problem of purity or cleanliness of the gas that resulted in the operation of private power plants (IPP) received serious attention. The cleaner the gas and the stable the gas supply so the more stable the operation of the power plant and the opposite. The purchaser or user of electricity also requires the amount of electricity supply and tolerance to the breaking or shutting down of electricity at a certain time which must be fulfilled by the provider or private power producer. Various gas cleaning technologies have been used to obtain clean and stable gas supply to the converting equipments used. Gas cleaning technology in addition must be cheap and also easy to use so that electricity providers remain profitable. In general, the gas cleaning technology is to clean the gas from its impurities including also reduce or eliminate the gases that potentially disrupt the operation of such conversion equipments. For example CO2 and H2S gases in biogas process or tar in gasification and pyrolysis. 

Water scrubber (absorber) and stripper unit for biogas refinery

JF BioCarbon continuous pyrolysis technology is the best choice of electricity production from biomass with thermal route. This is in addition to generated electricity, also produced side products that are not less profitable, namely charcoal, biooil, and biomass vinegar. Then how about cleaning the gas so that the power supply electricity continuously? With a number of line cleaning units that work alternately, the continuity of the supply of clean gas can continue to run so also with the supply of electricity. A number of sensors are installed to ensure the cleanliness of the gas. Downtime or power outages will be reduced or even eliminated. Sufficient gas cleaning will ensure the continuous operation of the gas engine generator as a conversion unit from pyrolysis gas (chemical energy) to heat and mechanical energy (reciprocating engine in gas engine) and generate electricity. It is time for private power companies (IPP) to consider slowpyrolysis technology to continue as a wise and best choice for the production of electricity from biomass and a number of byproducts that are very profitable.

Used Tire Pyrolysis: An Efficient Method Extracting Energy from Used Tires

Vehicle tires will only end up in landfills and objects made ​​of rubber is causing serious environmental problems. Every year around the world more than one billion vehicle tires discarded. Tire production in Indonesia also increased from year to year. Along with that, then the waste tires are not used in the environment is increasing. Most people prefer to throw it away than to recycle more useful results. Experts often confused with the environmental problems caused by tires that are not easily biodegradable material.

Conditions of use of energy is still dominated by fossil fuels should be reduced slowly and gradually replaced by renewable energy. According to Minister of Energy and Mineral Resources Darwin Zahedy Saleh , oil in Indonesia is expected to expire within the next 23 years and can not be updated. Petroleum is not used to meet energy needs but also as a raw material of chemical industry products such as plastics and tires.  

Abundant amount of used tires that can be recycled by thermal decomposition using pyrolysis to produce a primary product of petroleum that can be used as a source of energy or raw materials of many chemical industries. Other products in the form of carbon black will be widely used for coloring tires, syngas also for the application of energy or production of electricity and steel wire as raw material for metal casting.

Processing of used tires do not just simply solve the waste problem but also be economically advantageous. Great added value will be obtained when the product processing scrap tires have high economic value, a commodity that is always needed by communities and sustainable. The use of continuous pyrolysis technology is the right choice for the processing of scrap tires to produce petroleum products (crude oil), black carbon, syngas and steel wire, all of which have added great value and is the raw material of various industries.

Every 60 tonnes of scrap tires are processed in the pyrolysis can produce:
-18 000 liters of oil
-18 000 kg of carbon black
-6600 Kg of steel wire
-17,400 Kg syngas (synthetic gas)

Scrap tires are initially reduced size in about 1 inch and then go into the pyrolysis unit as the unit of production. A carbon black product, syngas, and crude oil will come out on the pyrolysis unit outlet. Syngas can be directly used for electricity generation using gas engine powerplant (gas generator), the capacity of 6o tons / day of INPUT will produce about 1 MW of electricity. While carbon black products of the pyrolysis unit will be passed in a magnetic separator for the separation of steel wire.

For many industries that are currently utilizing scrap tires as a fuel by burning it directly, so it is better to use the pyrolysis unit to extract the energy content in scrap tires. Direct combustion of scrap tires will cause a major environmental pollution and harm. It also does not provide much added value. Continuous pyrolysis will be able to extract the energy content of scrap tires effectively and efficiently, such as syngas produced from pyrolysis can be used as an energy source, because in that place no longer require an additional power supply, or use the crude oil produced for the same purpose .