Plant Boiler Research Articles

Single particle flame-combustion studies on solid biomass fuels

Combustion of solid biomass in large scale power generation has been recognized as a key technology for the transition to a decarbonized electricity sector in the UK by 2050. Much of the near-term forecast capacity is likely to be by the conversion of existing coal-fired pulverized fuel plant (DECC, 2012). In such applications, it will be necessary to ensure that the combustion behaviour of the solid biomass fuels is engineered to match, as far as practical, that of the original plant design. While biomass feedstock characteristics vary considerably, one controllable variable for pulverized fuel is the size of the particles.Useful modelling for adaptation and design of boiler plant can be improved with more detailed measurement of the real behaviour of individual particles of the varying fuels. Typical power plant biomass fuels including pine, eucalyptus and willow with particle sizes ranging from up to 3mm (Van Loo and Koppejan, 2008) and with differing moisture content and aspect ratios were selected for study. Single particles were supported in a water-cooled cover and then exposed above a flame, simulating biomass combustion in a furnace. Measurements of ignition delay, volatile burning time and char burn-out time were undertaken using high speed image capture. Temperatures of the surrounding environment and near to the particle surface were measured with thermocouples and thermometric imaging. Thermo-gravimetric measurements on separate samples complement the single particle measurements as a means of verifying the demarcation between the different stages of combustion and providing kinetic data.Analysis of the data identified correlations between the biomass fundamental characteristics, particle size, and the observed combustion profiles. Empirical expressions for the duration of each combustion stage have been derived. These have been validated with basic modelling including the predicted devolatilisation stage calculated by the FG-Biomass model (Chen et al.,1998).

Autonomous Maintenance: A Case Study on Assela Malt Factory

Purpose: M/S Assela Malt Factory (AMF) is the pioneer in malt supply to the breweries throughout the Ethiopia. The boiler plant faces machines failures, and rate of failures is increasing year after year, which affect the production cost. The important problems of the boiler plant are machine breakdown, machine idle, production loss, too much maintenance man hour, high maintenance expenses, and plant capacity loss. Objective of the research is productivity improvement through identification of problems in machines and the improvement of efficiency, employee’s attitude and culture of work.Quality in maintenance and the associated product quality is aimed to be enhanced by application of Autonomous Maintenance (AM) and set maintenance plan for the plant. Design/Methodology/Approach: The study proceeded with observation, data collection, related literature review; document analysis, interview, and giving training for the operators to embark upon 5S implementation at boiler house. A three steps approach for maintenance and improvement of the machine were implemented. First to set the cleaning procedure for the machine and work place, inspection and check for the cause of breakdown and initiate corrective action by maintenance, and final to assign the standard plan for maintenance.

Removal of total organic carbon (TOC) residues from power plant make-up water by activated carbon

Organic compounds decomposing in high temperature and pressure of a steam boiler plant water–steam cycle result in low molecular weight (LMW) organic acids and carbon dioxide. Subsequently a drop of pH value is observed in condensate which ultimately can cause corrosion. Organics may also contain for example chloride and release it to condensate. Thirdly decomposition products mask online cation conductivity measurements. This paper evaluates the use of activated carbon (AC) filtration as an option to remove the residues of organic compounds present in deionized make-up water. The experimental part was done using continuous flow bench scale AC filters (AC dry volume 3.75l, flow rate 25l/h, water temperature approximately 20°C) at a steam boiler desalination plant. Four commercial ACs were tested and all proved equally efficient removing approximately 42–45% of total and 58–68% of dissolved organic carbon after 30 days of operation. The most efficiently removed organic fractions were LMW neutral compounds, decomposition products of humic substances and hydrophobic compounds. Biopolymers were not effectively removed. Coconut shell based ACs leached more Ca, Mg and Na ions compared to coal based while for silica there were no differences. Pre-acid washing of ACs was efficient in reducing the initial leaching of impurities. However, the differences between acid washed and non-acid washed AC diminished with time. A mixed bed (MB) ion exchanger as a polishing treatment after AC filters is required to control the leaching of impurities.

English

This paper is a case study, involving mathematical modeling of boiler and heat exchanger pilot plant by System Identification procedure. This is done by using System Identification Toolbox. Some fundamental control oriented issues such as System Identification, mathematical modeling and controller designing by using basic control strategies are discussed in it. First of all data is acquired from boiler and heat exchanger set-up. This data is used to obtain mathematical model with the help of System Identification Toolbox available in MATLAB. Transfer function model is obtained from System Identification and controller response is observed for this model. A conventional PID controller is designed and controller performance is studied

MODELING COGENERATION POWER PLANTS USING NEURAL NETWORKS

As the energy cost is rising steadily and the environmental pollution is becoming an important issue, the roles of process plant boilers like that of the sugar plants boilers need better understanding as they can be made to operate in either energy conserving or bio-mass conserving modes. However, practical models of the plants need to be developed before any effort at optimization and cogeneration is carried out. These boiler plants are difficult to model as they have non-linearities between input and output parameters and have large no. of parameters. Efforts have been reported in literature where techniques like that of Neural Networks have been used. A similar methodology has been evolved here successfully to model a 100 Ton water tube bagasse fired cogeneration boiler through back propagation trained Neural Networks.

Implementation of Energy Efficiency Measures in a Semiconductor Building

This article focuses on the implementation of energy efficiency measures in a semiconductor building. Those measures include system optimization on the terminal units (TBs), office air-handling units (AHUs), make-up air units (MAUs), exhaust systems, fan filter units (FFUs), fan tower units (FTUs) and recirculation air-handling units (RAHs), fan coil units, and central chiller plant and boiler plant. Twelve permanent power meters were installed throughout the building to measure the total building electricity demand, solar generated electricity demand, HVAC and non-HVAC equipment demand to quantify the energy savings from the implementation of the energy efficiency measures.The electricity demand data have been collected for two years at 15-minute intervals and evaluated, with the energy saving adjusted by the outside air temperature. The electricity saving for this building is about 54.49 kWh/ft2/year (589.64 kWh/m2/year), which reduces the total building electricity consumption about 20%. The gas savings is about 0.1MMBtu/ft2/year (493 km3 of natural gas/year, 30% of the total building gas consumption) based on the daily reading from the facility engineer. The simple payback without incentives is 1.5 years.

Cogeneration unit with an absorption heat pump for the district heating system

The Imanta district heating plant began operation in 1974 as one of the main heating plants for the Riga district heating system. Until now, it has undergone several reconstructions. First, the ordinary boiler plant with steam and hot water boilers was reconstructed to be a natural gas-fueled combined cycle cogeneration plant supported with hot water boilers. Then, one of the cooling towers of the cogeneration section was replaced by an absorption heat pump/chiller, thus providing the closed cooling water circulation system and recovering 2 MWth (7 MMBTU/h) low-grade heat otherwise lost in the atmosphere. The driving force for the absorption heat pump is steam produced by the steam boiler (3 MWth = 10 MMBTU/h) already located at the boiler plant. The efficiency of the absorption heat pump is closely related to the operation of the cogeneration unit, outside temperature, and district heating water temperature regimes. The case study confirms that a more efficient energy production system reduces the fuel consumption with the same amount of the produced energy, thus lowering the expenses on energy production and reducing the amount of the polluting emissions into the atmosphere.

Atmospheric Pressure Deaerators for Heat Supply Systems at the South-West Power Plant

An atmospheric pressure deaerator with a capacity of 500 tons/h has been designed for use in the heat supply system at the JSC “South-West Power Plant”. It employs superheated (relative to the saturation temperature for the pressure in the deaerator) water with a temperature of 130 – 150°C as a heat transfer medium. Tests and operational data of the new DA-500/100 deaerator show that it operates stably, reliably, and efficiently within the design range of hydraulic and thermal loads, while the quality of the feed water after it meets the standards. The DA-500/100 deaerator with superheated water as the heat transfer medium is recommended for use in large heat supply systems in heating and electric power plants and boiler plants.

BIM을 BEM으로 전환할 때의 문제점과 전망

Recently, interoperability between BIM (Building Information Model) and BEM (Building Energy Model) has been highlighted. Even though it has been widely recognized that there are significant potentials in BIM by data sharing and reuse, BIM has not been actively utilized for building energy simulation. With this in mind, in this paper, the authors investigated several issues: (1) limitation of Industry Foundation Class (IFC) and BIM authoring tools, (2) immature IFC data schema, (3) data mapping problem between BIM and BEM. Firstly, IFC files exported from major BIM authoring tools are not consistent with each other and don't include significant thermal parameters. In addition, building geometry, e. g. underground wall, is not properly exported. IFC data schema are not ready to describe detailed information on thermal and dynamic properties (efficiency, performance curves, etc.) of mechanical systems (HVAC, AHU), delivery systems (fans, pumps), and plants (boilers, chillers), which are very essential for BEM. Finally, most of the efforts on BIM-to-BEM are focused on data conversion (data-driven approach), without considering dynamic architectural design process which involves many different stakeholders. In near future, BIM-to-BEM interface should take into account design context and rational decision making so called 'process-driven approach'.

Influence of Heat Gains in Building on Pumping Energy Consumption in Boiler Plant

Influence of Heat Gains in Building on Pumping Energy Consumption in Boiler Plant

КОНТРОЛЬ И МОНИТОРИНГ БОЙЛЕРА В ПРОМЫШЛЕННОЙ УСТАНОВКЕ ПРИ ПРОИЗВОДСТВЕ СЕРЫ В РЕСПУБЛИКЕ ИРАК

In boiler plants in the automatic set contains all the equipment required to ensure safe operation of the boiler with the observance of high economic and environmental indicators. Set of instrumentation and automation includes: control panel boilers, which contains the elements and devices of automatics of safety, automatic adjustment of the basic technological parameters. Automatics of safety is implemented on the basis of the relay circuit, which contains the logging devices water level in the boiler drum, pressure steam, the steam flow rate, actuating mechanisms control. The shield provides the installation of sensors control the burner flame and ignition.

Adding amines to steam for humidification

Humidity control is required in all health care facilities. Direct injection of steam from a central boiler plant is the most economical humidification system. The steam carries neutralizing amines—corrosion-inhibiting chemicals—that are added to boiler feedwater to prevent pipe corrosion. When the steam condenses, the amines neutralize the resulting carbonic acid and raise the pH of the condensate, which helps reduce, slow down, or prevent corrosion to the condensate system. This technical review compares the use of ‘clean steam’ to ‘utility’ steam and discusses the health effects, regulation, and control of three of the most commonly used amines in ‘utility’ steam: morpholine, cyclohexylamine (CHA), and diethylaminoethanol (DEAE) to make the point that proper application, control, monitoring and oversight of amines in a ‘utility’ steam system of a health care facility is safe, feasible and economical.

Анализ источников шума крышной котельной установки

Анализ источников шума крышной котельной установки

Assessment of primary energy savings by means of CHP systems in domestic energy supply

In this paper the assessment of primary energy savings of combined heat and power (CHP) systems is described by a primary energetic comparison of a coupled supply system (CHP plant, boiler and power plant) with a separated supply system (boiler and power plant). The plant-side power to heat ratio and the demand-side power to heat ratio are discussed as important system parameters for primary energy savings. The method suggests a theoretical potential of primary energy savings, which depends on plant-side characteristics only. The technical potential of primary energy savings is the consequence of plant-side and demand-side characteristics. In this paper an example application is presented for dynamic simulation of two different insulation standards in Germany, using the reference load profiles of the German technical guideline VDI 4655.

Regulating steam temperature in drum boilers by means of injection desuperheaters. initial investigation of the controlled object

The object of study was an automated system designed to control the feed of coolant water to the superheater tract of a TP-87 steam boiler used in a power plant. The dynamic characteristics of the superheaters were determined in relation to the channels used to transmit the control actions. It was established that a corrective system needs to be designed to automatically regulate the temperature of superheated steam for drum-type power boilers. An analysis of the system currently used on the above-indicated boiler for automatic control of the temperature of the superheated steam revealed the advantages, deficiencies, and limitations of the obsolete, worn-out system. The factors that affect the stable operation of the automated control systems of boiler plants were also determined.

Experimental Study on Volume for Fly Ash of Building Block

Fly ash is a waste substance from thermal power plants, steel mills, etc. That is found in abundance in the world. It has polluted the environment, wasting the cultivated land. This study introduces an experimental research on fly ash being reused effectively, the study introduces raw materials of fly ash brick, production process and product inspection, fly ash content could be amounted to 40%~75%. High doping fly ash bricks are manufactured, which selects wet fly ash from the power plants, adding aggregate with reasonable ratio and additives with reasonable dosage and do the experimental research on manufacture products for properties, production technology and selection about technology parameter of production equipment. Index of strength grade and freezing-thawing resisting etc and the high doping fly ash brick building which we are working on can achieve the national standard on building materials industry. Based on the tests, this achievement of research has a very wide practical prospect in using fly ash, industrial waste residue, environmental protection and reducing the cost of enterprises. The efficient reuse of fly ash from coal boiler and power plants has very vital significance of protecting the environment, benefiting descendants and developing of circular economy.

The Ottawa Hospital Energy Management Program

ABSTRACT The Ottawa Hospital (TOH) began its energy reduction program in 1991 when it became one of the first hospitals to install a heat recovery heat exchanger for the boiler plant flue gases at the Civic campus. With the exchanger, sized to recover 12 MMBH, the Civic campus has accrued gas savings since that time. In 1996 an audit of the Civic campus lighting and steam traps was completed, and implementation of the recommendations to correct the failing steam traps and redesign several systems resulted in significant gas savings. In 1998, three hospitals—Civic, General, and Riverside—were amalgamated under the new name “The Ottawa Hospital,” with a total area of approximately 3M ft2. In 2001 an energy manager was hired, whose primary role was to review utilities billing, establish projects that flead to energy savings, and prepare for deregulation of the Ontario electricity market. TOH developed an energy savings goal of approximately $2.5M annually to upgrade the infrastructure. A request for proposal (RFP) was posted to secure an Energy Service Company (ESCO) partnership. The successful ESCO implemented $17M worth of upgrades to lighting, HVAC controls, building envelope improvements, and water saving measures. The savings associated with the partnership exceeded the goal of $2.5M and were fully guaranteed. The final contract included a measurement and verification (M&V) component between the parties that would confirm the savings based on the whole building approach.

Catalytic heat-generating units for industrial heating

The design and operation of catalytic solid fuel-flamed heat-generating units intended for local heating of industrial and municipal facilities are discussed. An advantage of these units is that their thermal power can be regulated between 0.5 and 10 Gcal/h and that they are capable of burning various types of solid fuels, including low-grade ones and waste, in an environmentally friendly way. Data characterizing the operation of an industrial-scale boiler plant with a thermal power of 3 Gcal/h are presented.

20612 高効率廃棄物発電プラントにおけるボイラ過熱器管Alloy625 の高温腐食損傷機構(OS7-3【環境と調和したエネルギー利用(3)】)

In order to establish the failure mechanism by complicated hot corrosion in the high-efficiency Waste-to-Power (WTP) plant boilers, corrosive failure analysis was conducted by using the alloy 625specimen practically used as super heater tube of the advanced MSW incinerator boiler at Tsukui. On the basis of corrosive failure analyses using different analytical instruments such as TG-DTA, ICP, EDS, and FE-EPMA, the complicated hot corrosion process and mechanism were discussed.

Modeling Creep Behaviour of Boiler Grade Steels - Application to Grade 92 Steel

Power generation is now striving to improve the global efficiency of boiler plants, targeting 50% or higher. To accommodate the necessary increase in steam temperature, new materials may be developed and/or existing materials must be employed to their best. This is mandatory for the design of boiler components. One contribution by V&M in that direction is the setting up of numerical models for major boiler grades regarding their creep resistance. In coordination with Mines ParisTech, the first application has been made to Grade 92.The methodology is presented together with the first simulations. Typically, creep is modelled using two deformation mechanisms which correspond respectively to a low stress regime and a high stress regime. Damage is also taken into account. Calculations were carried out using ABAQUS ®. Numerical results are compared with a series of creep tests performed at Vallourec Research Aulnoye (VRA). Further development and applications of the model are finally discussed.