Draft Fan Research Articles

Optimization of Steam Boiler Airflow Control System in a Typical Oil Refinery Power Plant

This paper presents optimization of Steam Boiler Airflow Control System in a Typical Oil Refinery Power Plant. The power plant is equipped with four steam boilers using a damper-louvers airflow control system. Analysis has revealed significant energy wastage due to inefficiency and over-air supply, with the system requiring 59,904,436 kWh annually at a financial cost of N1, 093,255,884. The existing system's inefficiency results in an annual electrical energy waste of 8,502,302 kWh. This inefficiency is attributed to the Force Draft Fan (FDF) motor operating at maximum speed continuously, regardless of the steam profile or airflow requirements. This study aimed at optimizing the steam boiler airflow control system in a typical oil refinery power plant for improved power efficiency, energy conservation, and cost savings citing Port Harcourt Refinery Company (PHRC) at Alesa-Eleme, Rivers State, Nigeria. To address this, the damper-louvers system was replaced with a Variable Frequency Drive (VFD), which would adjust the motor speed to match the required airflow, thereby reducing energy wastage. The process was simulated and VFD/FDF motor analyzed in MATLAB Simulink, determining the optimal speed, airflow, and power requirements. Results obtained show that the VFD control system improves the FDF motor's power efficiency from 47.7% to 85%, with an annual energy saving of 8,502,302 kWh (8.5 GWh). This results in a total cost benefit of N478.18 million annually, representing a 43.8% cost saving. The implementation cost of the VFD infrastructure was estimated at N111, 440,000, with a payback period of approximately eleven months. The findings suggest deployment of higher FDF motor speed ratings to enhance speed control and energy efficiency in Oil refinery power plant.

Intelligent Combustion Control in Waste-to-Energy Facilities: Enhancing Efficiency and Reducing Emissions Using AI and IoT

Expanding waste-to-energy (WtE) facilities is difficult, and with tightening incineration regulations, improvements in WtE facility operations are required to dispose of waste that is increasing by an average of 4.8% annually. To achieve this, an intelligent combustion control (ICC) system was studied using digital technologies such as the Internet of Things and artificial intelligence to improve the operation of WtE facilities. The ICC system in this study is composed of three modules: perception, decision, and control. Perception: collecting and visualizing digital data on the operating status of WtE facilities; Decision: using AI to propose optimal operation methods; Control: automatically controlling the WtE facility according to the AI-suggested optimization methods. The ICC system was applied to the “G” WtE facility, a solid waste WtE facility operating in Gyeonggi province, Republic of Korea, and the digital data collected over six months showed high quality, with low delay and a data loss rate of only 0.12%. Additionally, in January 2024, the ICC system was used to automatically control the second forced draft fan and induced draft fan over a four-day period. As a result, the incinerator flue gas temperature decreased by 0.66%, steam flow rate improved by 2.41%, power generation increased by 3.09%, CO emissions were reduced by 60.72%, and NOx emissions decreased by 7.33%. Future research will expand the ICC system to include the automatic control of the first forced draft fan and the operation time of the stoker.

Experimental study on gas uniformity at the inlets of six cyclones in a CFB with multi-tracer gas method

To investigate the non-uniform distribution of different gases passing through the parallel cyclones, experiments were conducted on a circulating fluidized bed (CFB) equipped with six asymmetrical cyclones. A multi-tracer gas method was used, with CO, O2, and CO2 chosen to represent gases with different properties in the flue gas at the inlets of the cyclones. The uniformity of multi-gas distribution was evaluated by measuring the concentration deviations of each tracer gas passing through individual cyclones. The results indicate that the concentrations of multi-tracer gases are higher in the middle cyclone among the three, which are located on the tracer gas injection side during the test of single-side secondary air (SA) tracing. The maximum concentration deviation of tracer gases is for CO2, while the minimum is for CO. At the three cyclone inlets on the opposite side, the tracer gas with higher density exhibits a more uniform distribution, and the gas uniformity decreases as the density decreases. The effects of superficial velocity, SA ratio, bed inventory, and tracer gas injection region on the uniformity of gas distribution were studied. The results show that superficial velocity and SA ratio primarily affect the uniformity of higher density gases, while bed inventory has a greater influence on lower density gases. The gas distributions are most non-uniform, especially for CO2, when the tracer gas injection region is near the rear wall closer to the induced draft fan during the test of regional SA tracing.

Deflector device optimization for controlling nitrogen oxide emissions and pressure drop in selective catalytic reduction denitrification system

ABSTRACT Selective catalytic reduction technology effectively controls nitrogen oxide emissions from coal-fired power plants. In denitrification systems, exceeding nitrogen oxide emissions and excessive local pressure drop are common issues. Numerical simulation methods are used in this study to optimize the flow field to enhance denitrification efficiency and reduce pollutant emissions. Specifically, four deflector plate schemes for the variable-section flue duct segment are proposed. In actual retrofitting, the optimization scheme led to a reduction in nitrogen oxide emissions from 97.3 mg/Nm3 to 48.6 mg/Nm3 and an increase in the outlet pressure of the denitrification system from −3000 Pa to −2959 Pa, resulting in a 41 Pa decrease in local pressure drop. This optimization will further reduce pollutant emissions from power plants and the power consumption of induced draft fans.

APPLICATION OF TRI-VECTOR ANALYSIS TO IDENTIFY THE OPTIMUM COATING THICKNESS IN INDUCED DRAFT FANS

APPLICATION OF TRI-VECTOR ANALYSIS TO IDENTIFY THE OPTIMUM COATING THICKNESS IN INDUCED DRAFT FANS

Experiment study on particle pulverization-assisted convective air drying of sewage sludge

Sewage sludge drying is a pivotal step in sludge reduction, harmlessness, and resource utilization. Pulverizing sewage sludge can significantly increase the surface area of sludge particles available for contact with the air medium, consequently strengthening the convective drying process of the sludge. In this paper, the adopted deep drying system mainly combined sewage sludge pulverization and sewage sludge drying functions. Parametric studies were carried out to investigate the effects on the drying process. The moisture content of the sewage sludge decreased from 50.3% to 26.8% when the linear speed of the rotating blade tip of the pulverizing dryer and induced draft fan reached 28.3 m·s−1, 62.8 m−1, and air velocity reached 9.5 m·s−1, respectively. Furthermore, this work also preliminarily reveals the mechanism of the pulverizing dryer. The pores on the sludge particle surfaces are destroyed during the drying process. As the linear speed of the rotating blade tip in the pulverizing dryer increased, the hydrophilicity and the average particle size of the sewage sludge particles decreased, with the particle size representing the highest volume fraction being reduced by 62% in the particle size distribution. The pulverizing dryer not only breaks up the sludge to increase the surface area of the sludge in contact with the air but may also have a centrifugal effect. As the intensity of the pulverizing dryer increases, Nuclear Magnetic Resonance (NMR) measurements show a leftward shift in the peak of the weakly bound water in the sludge and a noticeable shortening of the transverse relaxation time. Overall, the results suggested that pulverizing is a suitable assistive method to improve the drying effect of the sewage sludge.

Redesigning the Element Profile of Air Preheater in Coal-fired power plants for Emission Reduction and Efficiency Improvement

PT PLN Nusantara Power Unit Pembangkit Tanjung Awar-Awar (UPTA) is a state-owned company that supplies electricity to areas of Java and Bali. Using coal as the main fuel, UPTA currently has two mills that each has capacity of 350 MW in coal-fired mode. Since the last few years, UPTA has been focusing on bringing efficiency into its overall operations, maximizing efforts for an improved output, modernizing machinery, and reducing emissions. After conducting routine inspection and examinations, UPTA decided to improve the air preheating element, so-called air preheater (APH), as an enabling condition to heat both the primary and secondary air to a temperature required for effective combustion in a boiler. To seek for an optimal APH, a redesign project was initiated to primarily change the element profile from a distorted wavy flow path to a linear flow path. The profile surface was coated with an added "enamel" layer, which prevents ash from adhering readily. Our measurements and calculations were based upon the data collected in October 2022 (pre- implementation) and within the periods of February to June 2023 (post-implementation). As a result, the average power consumption was reduced: from over 1740 kWh per month to become around 1377 - 1535 kWh per month, or 11% - 21%, for the induced draft fan (ID Fan) and from over 1900 kWh per month to become around 1450 - 1542 kWh per month, or 19% - 29%, for the primary air fan (PA Fan).

Research on structural resonance of large axial fan in power plant

According to the structural characteristics of the axial fan, the causes of equipment resonance are analyzed. Four reference methods are proposed, including strengthen the structural stiffness, change the exciting frequency, weaken the exciting force, and strengthen the damping. The characteristics of the response treatment measures are discussed. Take the two-stage axial-induced draft fan of a 600 MW unit as an example, the axial resonance problem has been dealt with well by improving the support stiffness and reducing the excitation force. The research results and treatment can provide an experience reference for the analysis and treatment of the resonance problem of large axial fans.

Application of ensemble learning approach on anomaly detection of a dual induced draft fan system

Intelligent monitoring of thermal power plants has been receiving growing interest. As one of the promising technologies in intelligent monitoring, machine learning-based fault detections for auxiliary equipment in the thermal power plant have been widely investigated. In this work, we constructed normal behavior models to predict the current of a dual-induced draft fan system by gradient-boosting tree regression. For anomaly detection, we evaluated the residual by calculating the mean value and meanwhile added a control boundary based on statistical analysis. As a result, we successfully identified the abnormal fan in the dual-induced draft fan system and assisted in the schedule of maintenance work.

Journal Vol – 19 No -1, January 2024 Journal > Journal > Journal Vol – 19 No -1, January 2024 RELIABILITY OPTIMIZATION OF A DEGRADED SYSTEM UNDER PREVENTIVE MAINTENANCE USING GENETIC ALGORITHM Authors: Shakuntla Singla, Diksha Mangla, Poonam Panwar, S Z Taj DOI NO: https://doi.org/10.26782/jmcms.2024.01.00001 admin January 20, 2024 Abstract: The reliability parameters of a Mathematical model are analyzed for

The present paper deals with the lacunary interpolation problem called the mixed values problem or (0, 3; 0, 2) problem for which known data points are function values at all the points, third derivatives at even knots, and second derivatives at odd knots of the unit interval I = [0,1]. For this problem, we obtained an interpolating function. The paper is divided into two parts, where we have shown that the spline function exists and is convergent.

Identifying Unbalance in Forced Draft Fan Using Vibration Measurement Methods

The Forced Draft (FD) Fan is a component in a power plant that serves as a supplier of secondary air to assist combustion within the boiler. The Forced Draft Fan has a motor coupled to an impeller, where this component often experiences imbalance with very high vibration values. The imbalance can affect performance and decrease the efficiency of the Forced Fan. Special maintenance in the form of balancing is required to reduce vibration values according to ISO 10816-3 standards so that the Forced Draft Fan can operate safely. In one power plant, there was a Forced Draft Fan experiencing unbalance on the impeller side. In this study, the highest vibration value for the Forced Draft Fan was found at the MOH point, measuring 4.75 mm/s, and after balancing, the vibration value decreased to 0.82 mm/s.

Energy and Exergy Analysis of Forced Convection Solar Drying of Allium Sativum With and With Out Sensible Heat Storage

In this article the energy & exergy analysis of forced convection solar dryer for drying of garlic has been investigated. The exergy parameter, air velocity has been taken to conduct the experiments and its effect on thermal efficiency. Forced draft fans were used in all the two working conditions. During the two conditions, with and without sensible heat storage system, the average air-velocities were 4.5, 9.5 and 11.4 m/s selected as ideal and subsequently its entire effect on thermal efficiency and outlet. The ambient temperatures were between (17-25) °C during the month of October and November. A DC fan is directly connected to the photovoltaic cell in the solar dryer. The thermal energy storage bed was packed with gravels with 1.5 in of thickness up to the surface of flat plate collector, the storage system becomes space-efficient. The average thermal efficiency with sensible heat storage materials was high as compared to system without sensible heat storage. The highest thermal efficiency of 61% was achieved. The maximum collector temperature obtained was 55 °C, with a mean temperature of 42 °C in the drying chamber. The collector’s greatest exergy loss was 30.38 kJ/kg and highest exergy efficiency was 70%.

Fault Diagnosis of Centrifugal Fan Based on Grid Search Optimized Voting Weighted KNN

Fan plays the roles of the forced draft fan, induced draft fan, primary air fan, seal fan, and powder exhauster. As an important auxiliary of the fossil-fuel power station, its working environment is harsh. Timely and efficient fault diagnosis can effectively reduce equipment failure and shutdown losses, and improve the efficiency of thermal power generation. K-Nearest Neighbour (KNN) has good classification ability for non-stationary data samples. In response to the shortcomings of the traditional KNN algorithm, this paper constructs a fault diagnosis model based on the voting weighted k-nearest neighbor algorithm. The model constructs a weight voting equation that is negatively correlated with the distance value based on the first k-nearest neighbors and then conducts fault diagnosis based on the voting score. We use grid search to optimize the model and select the k value in the model, and the relationship between the k value and accuracy was verified. The grid search optimization voting weighted k-nearest neighbor is used to diagnose the faults of nine common operating states of centrifugal fans, and the diagnostic accuracy can reach 100%.

Power plant induced-draft fan fault prediction using machine learning stacking ensemble

The improvement of fault prediction and diagnosis in industrial systems is crucial to minimize unscheduled shutdowns. However, the predictive performance of current models for thermal power plants is limited due to their reliance on single algorithm approaches. Furthermore, there is a shortage of experiments on thermal fired power plant equipment, as most research focuses on nuclear power plants. In this study, we propose a fault predictive stacking approach for a thermal power plant induced draft fan and evaluate the performance of base learners, including Support Vector Machines (SVM), K Nearest Neighbors (KNN), and Random Forests (RF). Our proposed stacking ensemble approach achieved a prediction accuracy of 99.89 % which demostrated superior prediction performance compared to the base methods.

KAJIAN TEKNOLOGI PEMANFAATAN BIOGAS POME (PALM OIL MILL EFFLUENT) KE BOILER


 In collaboration with BPPT, PTPN V management starting in 2018 took place at the Sei Pagar Mill PTPN V in Riau Province, planning the implementation of Biogas to Boiler technology to maximize the use of Biogas. The study aims to substitute shells for steam boilers / kettle through the scheme of using biomass POME to boilers at palm oil mills. The Utilization Model is a simple representation of a complex process in reality. To produce the scheme the model was preceded by conducting technical studies and economic studies and comparative studies on several Mill s in Sumatra and Kalimantan. From some of the findings from the studies that were compiled, one of the most suitable models will be made that will be applied in the Sei Pagar Mill. Furthermore, from the model, still through the RISTEKDIKTI Flagship Insinas Program, it will be developed to produce Prototypes and Construction / modifications to the Existing Boiler that is applied to the Sei Pagar Mill . Utilization Model Scheme. Biogas POME to Boilers at Palm Oil Mill by applying Biogas to Boiler technology includes several components of equipment, such as: Blower, Piping System, Valve Train, Gas Burner (Single Burner), Forced Draft Fan, and Control Panel (PHB). Utilization Model. Biogas POME to Boilers at Palm Oil Mill can later be developed and implemented to support the application of Biogas to Boiler technology at Palm Oil Mills in Indonesia.
 Keywords: Steam Boiler / Boiler, Blower, Piping System, Valve Train, Gas Burner (Single Burner), Forced Draft Fan, and Control Panel (PHB)

Cyclic Oxidation Behavior of HVOF Thermally Sprayed WC Cermet Based on AISI 1045 Steel

Thermal spray coating technology High-Velocity Oxygen Fuel (HVOF) has become one of solution for metal protect and parts recondition that work in critical environments such as oxidative, erosive, and corrosive. One of the thermal spray coatings (TSC) application has been carried out to improve the oxidation resistance of the Induce Draft Fan (IDF) as a part on coal fired steam power plant unit. Cermet WC10Co4Cr and WC17Co are intended to sustain the AISI 1045 steel substrate against the oxidative environment. In this works, the cyclic oxidation at a temperature 500oC were conducted to reveal the oxidation resistance behavior of the coatings. Several mechanical tests are also presented including surface roughness of the coatings, coatings microhardness, and coatings adhesion. The coatings morphology was also characterized using SEM microscope, as well as X-ray diffraction (XRD) for phase analysis after the oxidation test.

Study on moving fire smoke characteristics and mechanical ventilation system of tunnel

Limited by the narrow space of the tunnel, fire has become one of the important factors threatening the safe operation of subway especially the fire on a moving vehicle. Researches on moving fire through the large length-width ratio of tunnels are extremely lacking at present. This study investigates the characteristics of moving fire and the influence of mechanical ventilation under different conditions. First, a three-dimensional model of the tunnel with the moving train is established, and the dynamic mesh simulation is conducted and validated by the experiments. Then, the variation of smoke temperature distribution under different fire source intensities, train speeds, and blocking ratios are studied. Based on the smoke flow characteristics, the mechanical ventilation with different layouts of draught fans is investigated. It is found that the maximum growth rate of smoke spread is 70.90% with an increase of two fans. Finally, the influence of the tunnel shaft on the smoke characteristics under different fire source locations is discussed. When the fire source is under the shaft, the smoke discharge efficiency reaches the highest, almost 5.89% and 21.91% higher than other conditions. This study provides the basis and reference for the research and control of the tunnel moving fire.

INDUCED DRAFT FAN DOMINANT FREQUENCY DETECTION USING SHORT-TIME FOURIER TRANSFORM METHOD

Weak suction and large vibrations indicate an Induced Draft Fan (IDF) problem. The Fast Fourier Transform (FFT) method cannot be applied to non-stationary vibration signals. Therefore, this study aims to analyze non-stationary vibration signals for IDF vibration signals at start-up so that the source of damage to the IDF can be found. The research process begins with a brief measurement of both bearing locations with horizontal and axial axes. Processing of the vibration signal from the measurement using the FFT method and the Short Time Fourier Transform (STFT). Based on the STFT spectrogram graph for measurements on the horizontal and axial axes, the dominant frequency values are the same. The frequency with the largest amplitude value is at one RPM IDF or 25 Hz. High vibration at 1 RPM is a big indication that the IDF is experiencing unbalance.

Condition-Based Monitoring of Kiln Induced Draft Fan in A Dry Process Cement Plant for Efficient Utilization

Associated downtime and economic loss caused by replacement/maintenance of equipment necessitated pro-active technique known as Condition-Based Monitoring to prevent/reduce failures. This study evaluated the vibration of Kiln Induced Draft (KID) of cement plant before and after failure. Vibration data was acquired using accelerometer probe and data obtained were analyzed statistically by employing t-Test at 95% confidence. Results showed that vibration signals measured in mm/s for KID motor and fan bearings (non-drive and drive ends) in the horizontal plane recorded higher values than vertical and axial planes when measured before failure occurrences. After failures, horizontal plane values increased by more than 120% while those measured in the vertical and axial planes increased by less than 100%, making horizontal plane vibration measurement a more suitable parameter for predicting the machinery health condition. The t-Test conducted showed that mean differences in values of vibration signal data before and after failure are not zero but negatives (signal before failure < signal after failure). Outputs from tests of significance using two-tailed t-Test indicated that the differences in values of vibration data signals are not significant at (p≤ 0.05) when considering “equal variance not assumed”. The non-significance of these mean differences may indicate that the present operational vibration signal levelshould be maintained at lower values in order that significant difference may be observed between periods before failure and after failure for efficient prediction of failure;as the present 1.5-3.5 mm/s range is likely not a good range for efficient failure prediction.

Pad type impact on the economical direct- evaporative air cooler efficiency

ABSTRACT Theoretical and experimental investigations were performed to study the impact of four pads in series on the thermal performance of an economical evaporative air cooler that works at a low voltage (12 Volts). Straw and cardboard pads were studied. The studied parameters were dry bulb temperature, the dry bulb temperature difference between inlet and outlet air, cooling efficiency, and the total heat transfer rate. Three draft fan speeds were considered, i.e. 2.8, 3.5, and 4.7 m/s. The results showed that adding multiple pads in series had an insignificant impact on the evaporative cooler thermal performance compared to one pad. The straw pads’ cooling efficiency at 2.8 m/s was lower than that of the cardboard, i.e. 91.4% and 93.1%, respectively. Also, it was found that the velocity of the air passing through the cooler significantly impacted the cooling efficiency. The theoretical results for the lowest speed of 2.8 m/s showed an increase in the cooling efficiency of the cardboard pad by 46.6% compared to the speed of 4.7 m/s due to a long time for heat transfer. Therefore, the best air velocity entering the cooled space was 2.8 m/s.