One of the biggest export commodities in Indonesia is palm oil. Along with the high commodity of palm oil, the demand for palm oil production is also higher. Production of palm oil causes air pollution. The Roundtable on Sustainable Palm Oil (RSPO) is present in the development and implementation of global standards for sustainable palm oil mills.
According to RSPO indicators and guidelines, boiler emission-quality must meet international standards. Types of boilers for oil palm are generally boilers which can consume waste fibers and palm oil shells. In its development, evaluation of boiler use must be supported by dust collectors resulting from combustion residues. The simple dust collector for boilers commonly used is a cyclone.
Cyclone type is the simplest and cheapest dust collection separator because there are no moving parts. The efficiency is 99 percent for particles greater than five μm, and it can be operated at very high dust intensity.
The high production of palm oil will be followed by an increase in industrial plants, especially the use of boilers. Environmental problems can be reduced by installing dust collectors. The most favorite dust collector in factories is a cyclone.
Investigation of pressure drop for biomass boilers is very important because it is related to boiler performance. Cyclone, as a dust collector in boilers, has a large impact on reducing static residues. The purpose of this study is to observe good pressure of industrial-scale cyclones. Several approaches have been calculated and evaluated by cyclone kettle experiments at palm oil mills.
Increasing the speed of pressure results in an increased collection of dust particles. Then, the theory to reduce cyclone pressure emerged. The distance of airflow in the outer vortex and the dimensions of the cyclone greatly determine the amount of pressure produced.
Numerical data has also been reported and developed to reduce pressure during the combustion process. The latest report in 2011 showed the efficiency and a decrease in pressure of 91.1 percent against 90 percent and 480 Pa, which was desired for pressure drop.
The trial was carried out on the cyclone design for small capacity cement industries. The computational fluid dynamics model (CFD) was also developed in this study. The turbulence model is selected with k-epsilon. The standard k-epsilon model is a turbulence model used assuming the Reynolds voltage is proportional to the average velocity gradient, with the constant proportion characterized by turbulent viscosity (µt) known as the eddy-Boussinesq viscosity approach.
The static pressure of the exhaust gas is measured by a liquid pressure gauge (-400 mm wg to 0 mm wg). The flow rate selected with the operation of a full Induced Draft Fan damper with constant control of air intake and fuel in the boiler combustion chamber. Before measuring the pressure drop, the flow rate of the exhaust gas boiler has been checked with a digital pitot tube (Testo 350). The flow rate and exhaust gas temperature during the experiment were 870 – 890 CMM and 200 – 210 o C. Pressure drop data in several approaches with experiments. The actual experiment produced 90 mm wg (water gauge) of the value of pressure drop with a deviation of 7 percent, 94.05 percent, and 14.8 percent, respectively.
The use of the method with the lowest deviation in this study illustrates that the pressure drop approach can produce more parameter design. These results can be considered inlet and decrease outlet pressure. CFD simulations produce a standard deviation of k-epsilon medium, which is derived as a mathematical model. And, it can be concluded that k-epsilon for circulating turbulent gas flow is bad for cyclones. The dust loading effect must be investigated further to calculate the interface pressure drop.
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Details of this research available at:
Intan Ayu Pratiwi*, Helmi Dadang Ardiansyah, Pressure drop investigation of industrial scale cyclone for palm oil fiber boiler, IOP Conf. Series: Earth and Environmental Science 259 (2019) 012018, doi:10.1088/1755-1315/259/1/012018