Plant Boiler Research Articles

Young Dong Unit 1 Oxyfuel Feasibility Study and FEED

It is proposed to demonstrate oxyfuel technology at the 100MWe scale in KOSEP's 125MWe Young Dong Unit 1 Power Station. Prior to this it will be necessary to convert the existing boiler from anthracite firing to bituminous coal firing as the domestic anthracite source is nearing exhaustion. The oxyfuel demonstration project is being undertaken by a consortium of industrial companies, research agencies and universities, with the financial support of the Korean Government. Phase 2 of the project, the FEED, is nearing completion. Within this phase DPS have undertaken the design of the boiler plant. Key issues considered included the strategy to convert the boiler to bituminous coal, and a feasibility study investigated the various options. Having selected the preferred option the boiler thermal performance and burner operation under air and oxyfuel operation was determined. It was shown that it is technically viable to convert the boiler for oxyfuel operation.

Italian Residential Buildings: Economic Assessments for Biomass Boilers Plants

Biomass is increasingly used for energy generation since it represents a useful alternative to fossil fuel in order to face the pollutions and the global warming problem. It can be exploited for heating purposes and for supplying domestic hot water. The most common applications encompass wood and pellet boilers. The economic aspect is becoming an important issue in order to achieve the ambitious targets set by the European Directives on Renewable Sources. Thus, the present paper deals with the economic feasibility of biomass boiler plants with specific regard to an existing residential building. An Italian case study is further investigated, focusing the attention on European and national regulations on energy efficiency and considering the recent public incentives and supporting measures. The main thermoclimatic parameters—that is, heating degree days (HDDs), building thermal insulation and thermal needs—are taken into account. Moreover, the following economic indicators are calculated: cumulative cash flow, discounted cumulative cash flow, payback period (PP), net present value (NPV), Internal rate of return (IRR), discounted payback period (DPP), and profit index (PI).

Industrial Research of Condensing Unit for Natural Gas Boiler House

Abstract In the course of work industrial research was carried out at the boiler plant A/S “Imanta” where a 10MW passive condensing economizer working on natural gas was installed after the 116MW water boiler. The work describes the design of the condensing economizer and wiring diagram. During the industrial experiment, the following measurements were made: the temperature of water before and after the economizer; the ambient temperature; the quantity of water passing through the economizer; heat, produced by the economizer and water boilers. The work summarizes the data from 2010-2011.

Sustainable Use of Regional Wood Biomass in Kushida River Basin, Japan

The amount and cost of wood biomass produced from the Kushida River basin in Japan were simulated under current and modified forestry scenarios by combining the forest ecosystem and cost calculation models at semi-compartment level; in addition, an analysis was carried out comparing the sustainable supply against heat demands in the basin. The forest ecosystem model (BGC-ES) simulates biomass growth, the effects of thinning and clear-cutting practices, and the amount of harvest from these practices. The cost calculation model estimates the cost of each stage of wood biomass production, which depends on the productivity of forestry machines and the forest location. The available amount was determined by an economic comparison between the energy density of wood chips and fossil fuel. The available wood chips were assumed to be converted to heat at a boiler plant. The current forestry scenario (thinning schedule, rotation length, and managed area) was not efficient for the production of wood chips. The economic available amount was <1 % of the potential production from the basin forests. Modified scenarios (arranging the thinning schedule to promote secondary growth, increasing the rotation length, and increasing the managed area) improved the economic availability of the basin forest (up to about 40 %). In these scenarios, the available amount indicated that saturation was determined by the maximum cost of the wood chips. The available amount of wood chip production that can be sustainably supplied by the basin forest was simulated and compared with the household and agricultural demands for heat in the basin.

Energy efficiency and carbon dioxide emissions reduction opportunities in district heating source in Tianjin

Building a trading market can promote energy conservation provided that the trading method is determined. Energy consumption for heat supply is huge. Tianjin Municipal Government is planning to establish an energy efficiency trading platform for district heating taking into consideration the experience in carbon trading market and specific situation in Tianjin. This paper presented an in-depth analysis of the district heating industry in Tianjin municipality, and identified the potentials of energy saving and carbon dioxide emissions reduction. Since energy efficiency was closely related to different heating source technologies, baselines were determined for boiler plants and thermal power plants respectively. Three scenarios were discussed for baseline determination. 472 boiler plants were surveyed and operational data relating to energy consumption were collected. Through data analysis, 27 boiler plants which have reasonable recorded energy consumption values were chosen as samples. By analyzing the dataset and referring to the related standards, method of determining the baseline for district heating carbon market was established. Finxally, the baseline for boiler plant was determined to be 52.0 kgce/GJ, and that for thermal power plant was 43.0 kgce/GJ in 2011. Carbon abatement against the baselines above was calculated and considerable carbon dioxide emissions reduction could be achieved.

Optimizing Energy Saving Opportunities in Food and Dairy Plant Steam Boiler Systems

ABSTRACT Food and dairy plants typically employ nominal 100-135 psig steam generated by firetube boilers. A significant number of options in equipment are available to assist in optimizing energy consumption. In addition to properly matching boiler size to anticipated steam demand and maximizing the return of steam condensate, some or all of the following opportunities are applicable to both renovated and new boiler plants: 1. Operation at the lowest possible steam pressure2. Boiler selection with high turndown burners3. Economizers: i. Stack-sensible heat only ii. Stack-condensing iii. Direct contact-condensing iv. Indirect contact-condensing 4. Continuous surface blowdown heat exchangers5. Reverse osmosis (RO) treatment of boiler make-up water to reduce blowdown and chemical consumption6. Oxygen (O2) trim control Most of the above opportunities can be considered as “common sense,” but many owners are reluctant to increase the steam system first costs by including any or some of the possibilities listed. It is the design engineer's responsibility to provide cost analysis and payback(s) to justify added first cost for energy saving opportunities.

Multivariable PI control for a boiler plant benchmark using the Virtual Reference Feedback Tuning

In this work, the Virtual Reference Feedback Tuning is applied to the control of a boiler plant benchmark. Only data (without any modelling step) was used to compute a series of PI controllers for both a decentralized and a complete multi-loop control strategies. When compared with other PI controllers, it was found that a better tuning of the controller was achieved yielding better closed-loop results. The original VRFT method was enhanced with a series of constraints during the optimization process that allows the user to select the position of the zero of the controller.

Technological processes of increasing the efficiency of calorific value of coal as the energy resource of the Gacko deposit

This paper describes the conceptual technological processes of coal preparation and processing from the deposit Gacko (Republic Srpska) to the aim of increasing the efficiency of calorific value of fuel for the needs of Thermal Power Plant Gacko.The excavated coal from the coal deposit Gacko is supplied as the energy fuel for the needs od Thermal Power Plant Gacko as well as for commercial consumption. From total output of coal from from the open pit, which annually amounts on average to 2.2 Mt, and 97% is supplied for the needs of Thermal Power Plant Gacko and 3% forcommercial consumption. During previous mining (1983-2012), some deviations were recorded regarded to the results of calorific value of coal, obtained by detailed geological explorations and the results obtained from laboratory analyses on dosers in the Thermal Power Plant Gacko The average calorific value of coal in the deposit Gacko, obtained by geological explorations is 10.2 MJ/kg. The coal deposit Gacko has a complex geological structure and the carbon layers are stratified by substantial numbers of interbeds, thickness of 0.2 to 0.5 m. The selective mining is used for excavation the interbeds of interlayer waste, thickness greater than 0.2 m, and all minor interbeds are mined together with the coal. This technological solution of selective mining does not achieve the optimum economic effects of utilization the carbon material from deposit. The energy fuel of caloricif value from 8 to 8.5 MJ/kg is supplied for the needs of Thermal Power Plant Gacko and and it is lower than the designed parameters for the boiler plant in the Thermal Power Plant Gacko (9.2 MJ kg). Technological methods of coal upgrading and classification would increase the calorific value of coal in relation to the mining conditions.

Impact of climate change on building energy use in different climate zones and mitigation and adaptation implications

Impact of climate change on energy use in office buildings in a city within each of the five major architectural climates across China – Harbin (severe cold), Beijing (cold), Shanghai (hot summer and cold winter), Kunming (mild) and Hong Kong (hot summer and warm winter) – was investigated for two emissions scenarios. For low forcing, the estimated increase in cooling energy use was 18.5% in Harbin, 20.4% in Beijing, 11.4% in Shanghai, 24.2% in Kunming and 14.1% in Hong Kong; and the reduction in heating 22.3% in Harbin, 26.6% in Beijing, 55.7% in Shanghai, 13.8% in Kunming and 23.6% in Hong Kong. Space heating is usually provided by oil- or gas-fired boiler plants, whereas space cooling mainly relies on electricity. There would certainly be a shift towards electrical power demand. More energy use in buildings would lead to larger emissions, which in turn would exacerbate climate change and global warming. Energy conservation measures were considered to mitigate the impact of climate change on building energy use. These included building envelope, indoor condition, lighting load density and chiller coefficient of performance. It was found that raising the summer indoor design condition by 1–2°C could result in significant energy savings and have great mitigation potential.

A guide to developing and implementing safety checklists: Plant steam utilities

AbstractSteam generation is an integral part of most chemical process plants; however, the steam plant often is or can be overlooked in the area of hazard analysis. The reasons for this oversight are obvious: steam generation is considered to be an old and well‐understood process, and steam boiler systems are often not considered to pose the same hazards as other plant units. However, modern steam boiler systems are fueled with natural gas, pulverized coal, and/or fuel oil; each of which poses significant fire and explosion hazards. For example, a moderately sized chemical plant's boiler house may have two or three boilers operating at 240 MMBTU/hr, with each using approximately 11 ton/hr of subbituminous pulverized coal feed. Chemical plants rely on equipment design and installation, maintenance practices, operating procedures, and programmable logic controllers to operate safely. Steam plants rely on these same safety mechanisms. Thus, the same process safety management objectives may be applied to these systems as to the balance of the chemical plant.Several hazard analysis techniques can be applied to existing designs, management of change, and new designs of steam power plants in chemical facilities. A method that we have found useful to apply to these systems is that of a safety checklist based on relevant standards and good engineering practice. More than just identifying the hazards and required safeguards for such a system, if implemented effectively, the checklist will enhance training and staff knowledge of boiler operation and safety systems. This paper aims to provide guidelines for when it is appropriate to implement a checklist and for reasonable alternatives for developing such a checklist. We will also discuss typical hurdles in implementing such a hazard analysis program for existing boiler systems. © 2011 American Institute of Chemical Engineers Process Saf Prog, 2011

Water Level Control System of Boiler Drum Based on GPC

The paper discusses a TS fuzzy model identification method for an industrial drum-type boiler plant using the fuzzy clustering approach. The fuzzy model is constructed from a set of input-output data that covers a wide operating range of the plant. Then this paper studies the application of GPC algorithm in drum level control system Based on the T-S fuzzy model, simulates the control effect of the controller in the MATLAB environment, and analyze the performance of the control system.

Ion Exchange Study of Some New Copolymer Resins Derived from 8‐Hydroxyquinoline‐5‐sulphonic Acid, Biuret and Formaldehyde

Copolymer resins (8‐HQSABF) were synthesized by the condensation of 8‐hydroxyquinoline‐5‐sulphonic acid and biuret with formaldehyde in the presence of hydrochloric acid as catalyst, proved to be selective chelation ion exchange copolymer resins for certain metals. Chelation ion exchange properties to these polymers were studied for Cu2+, Cd2+, Co2+ and Zn2+ ions. A batch equilibrium method was employed in the study of the selectivity of the distribution of a given metal ions between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in a media of various ions strengths. The polymer showed a higher selectivity for Cu2+ ions than for Cd2+, Co2+ and Zn2+ ions. Hence on the basis of above studies these copolymer may be used as semiconductors, surface coating, ion‐exchangers, materials for rechargeable battery cell in various electronic industries, plastic materials, elastomers and in boiler plants

Design of robust H ∞-controller for energetic boiler plant

A problem of robust controller design for control of a boiler plant is solved using an H∞ loop-shaping method with constraints imposed on regional pole placement of transfer functions of the closed-loop system, and linear matrix inequalities tools. Requirements to the closed-loop system are formulated both in the form of frequency constraints on singular values of transfer function of the open-loop system, and in the form of pole placement constraints for the transfer function of the closed-loop system as a given region on the complex plane. A reduction of the full-order H∞-controller obtained in the design procedure is performed.

Thermodynamic simulation analysis of a multifuel CHP plant basing on the technological diagram of Avedøre unit 2

Thermodynamic simulation analysis of a multifuel CHP plant basing on the technological diagram of Avedøre unit 2 The paper presents the results of a simulative thermodynamic analysis of a multifuel CHP plant basing on the technological diagram of Avedøre 2. Calculations have been carried out for the operation of Avedøre 2 plant in the district heating mode. Several variants of simulation have been considered, determined by the choice of operation of the respective plants, viz. main boiler fired with natural gas, main and biomass boiler, main boiler and GT plant, joint operation of the main and biomass boiler and GT plant, main boiler (fired with heavy fuel oil or/and wood chips) and biomass boiler and GT plant. For each variants a diagram of iso-fuel curves has been developed, illustrating the variability of useful effects (power output and district heat) at various loads of the CHP steam part. In case of the variant in which the main boiler and GT are in operation with natural gas as fuel the exemplary energy indices were determined.

040 ボイラ用フェライト系ステンレス鋼のオーステナイト系に対する意義性に関した一考察 : 鉄鋼材料所見報告書(GS5-2 一般セッション)

In generally, it is usual used austenitic stainless steel in boiler tubes and pipes. Recently, another stainless steel, ferrite steel is often used at boiler plants but it is thought the setup place of that's steel is appriate in the sea or on the ground as endurance of erosion and corrosion and so on. Detail scription is described by each specialized researchers and studys in laboratories. In this time, I absent from presentation of the paper or thesis, described personal opinion as the end-user.

Air contaminants modelling by use of several receptor-oriented models

Two data sets were apportioned by the use of several models (chemical mass balance (CMB), principal components analysis-absolute principal components scores (PCA-APCS), positive matrix factorisation (PMF) and UNMIX). Source apportionment were results derived from the CMB modelling applied to the data from Vienna point traffic source, paved road and crustal dust as the dominant contributors to the PM10 total mass. The major contributors of PM10 aerosol mass in Cracow with respect to PCA-APCS, PMF and UNMIX applied include: boiler, stoves and industrial power plants (coal), secondary emission (including coal), gasoline, soil and road dust.

The effect of water quality on reliability of boiler plants performance

This paper presents sources and types of corrosion processes of boiler tube system of the Thermal Power Plant "Ugljevik". The main goal in the electric power production is to achieve lower prices, which can only be done by providing low maintenance costs. While it is not possible to completely stop corrosion, it could be slowed down and it's effects could be reduced. In order to reduce corrosion to a minimum on thermal power plants' vital equipment, particularly boilers, it is necessary to determine in each particular case the acting mechanism of corrosion and agents that cause it. Damages and failures on thermal power plants are largely caused by the development of various types of corrosion processes. Special attention is given to the preparation of water, considering its importance to the occurrence of corrosion. The following types of corrosion were detected on the screen tube boiler by visual examination on the side of water and steam: erosive, pitting and impact corrosion. The inner surface of screen pipes, from which the scale layer was removed, indicates that the erosive corrosion with the thinning of pipe walls occurs. Perforation of the welded screen pipes shows that stress corrosion occurred on the screen pipe with formation of cracks and that pipe exploded. Pits on the inner surface of the screen pipes, visible after the removal of scale and corrosion products, are proof that pitting corrosion occurred. The causes of corrosion were discovered and proposed measures for their elimination were given.

Control and Stabilization of a Multiple Boiler Plant: An APC Approach

A multiple coal fired boiler house provides steam for utility usage in various production plants. Maintaining stable header pressure and boiler availability is of critical importance for downstream consumers. Advanced Process Control comprising of a G2 based expert system and Model Predictive Control was implemented to improve the boiler house performance. The results yielded improvements in the main header pressure stability, reduction in boiler saturation and significant saving in coal consumption.

Noise Reduction for Boiler Plant

Noise Reduction for Boiler Plant

Numerical investigation of full scale coal combustion model of tangentially fired boiler with the effect of mill ducting

In this paper a full scale combustion model incorporating upstream mill ducting of a large tangentially fired boiler with flue gas recirculation was examined numerically. Lagrangian particle tracking was used to determine the coal particle paths and the Eddy Dissipation Model for the analysis of the gas phase combustion. Moreover volatiles and gaseous char products, given off by the coal particles were modelled by Arrhenius single phase reactions and a transport equation was solved for each material given off by the particles. Thermal, prompt, fuel and reburn NOx models with presumed probability density functions were used to model NOx production and the discrete transfer radiation model was used to model radiation heat transfer. Generally, the findings indicated reasonable agreement with observed qualitative and quantitative data of incident heat flux on the walls. The model developed here could be used for a range of applications in furnace design and optimisation of gas emissions of coal fired boiler plants.