Recently air pollution is becoming a global environment issue. Especially, the smoke from engines and boiler systems, which burn fossil fuels directly, is an extremely serious issue. For this reason, IMO is tightening regulations for the control of NOx and SOx. Therefore, in this study, the NOx reduction effect of emulsified oil mixed with 10% of water was tested after applying the emulsified oil to an industrial boiler burner using Bunker-C oil. The study showed that the exhaust gas oxygen concentration of emulsified oil was nearly 1.3% high and this was identified by the effect of dissolved oxygen contained in water. Also, based on the standard oxygen concentration(4%), the average and maximum NOx reduction rates were 28.53% and 30.23% respectively, which means the reduction efficiency was very high.

An electric steam boiler equipped with a condensate recovery system, which stores the condensate generated after using steam in steam washers, steam cookers, steam irons, and steam cleaners in a condensate tank and supplies compressed air to the condensate tank so that the condensate is recovered to the boiler by the pressure of the compressed air, was studied. In the results of this study, the heat energy balance between the quantity of the heat generated by the non-metallic surface heating element and the quantity of the heat absorbed by the water was good in a range of ±5%. In addition, the heat transfer rate increased in proportion to the electric power of the surface heating element heater, the waste heat energy was normally recovered by the recovery of the condensate of the steam boiler equipped with the high compression waste heat recovery system, and the recovery rate of the waste heat exhibited 23%.

Depending on the living styles, the types of energy consumed by households have changed, and the consumption has increased rapidly. Consequently, those have led to environmental issues, such as exhaustion of energy and the climate changes. As one of solutions to such issues, energy efficiency can be approached. Therefore, in this study, the gas water heater(115S type Rheem products) that made in Germany and obtain hot water using gas as a heat source is selected. a 1.0㎥ water tank with a 6kW electronic heater is installed and a water temperature and pressure is maintain constantly also thermometer is injected. Two of gas meter, one of pressure regulator and three of time measurement devices are installed in a combustion facility and fuelling facility with a magnet valve so it can observe and record combustion reactions. Quantity of hot water that heated by boiler is recorded using a quantity measurement tank, and have been heated by the boiler have been to record and measure the amount and utilized the data acquired through measurement of all factors that are applied to acquire hot water in order to calculate the use rate of final energy. In conclusion, this researcher drew the economic strong points of the hot water generated by gas.Key

As Crosby notes, the most companies spend 15 to 20% of their sales dollars on quality costs. Generally the most effective way to manage quality costs is to avoid having defects in the first place. In this paper we have studied about the repair(service) problem of domestic gas boiler within warranty period. We develop a system, which man could find the cause of the problem at an early stage and could devise a countermove to the problem under supposing that the service(repair) rate follows exponential distribution and the product is manufactured lot-for-lot continually. Using the developed early sensing system. it is expected to improve the reliability of the product, to save expenses of company and to improve customer’s satisfaction. And the system will be expended to incorporate information technology, which can detect the repair rate automatically.

The performance of electric boiler using thick-film heater has been investigated experimentally. Electric boilers are using thick film heater is composed of four to a water chamber. In this study, the water flow rate while changing then umber of heaters and heating performance was evaluated. One water chamber, the average heat release is approximately 6.63kW. And average heat release of four water chamber is about 29.08kW. The energy efficiency of the water chamber 4 was 95.4%. Finally, the average heat release and energy-efficiency of electric boiler is increased with increasing water chamber number.

본 연구는 콘덴싱 보일러 내부에 들어가는 원심 터보형 송풍기의 성능 향상 및 그 유동특성을 파악하고자 하였다. 보일러는 연소를 위해 반드시 필요한 가스와 공기의 양이 조절되어야하며, 이를 위해 송풍기는 보일러 내부의 한정된 영역을 차지한다. 한정된 영역에서 최적의 효율을 얻기 위해서는 케이싱 및 임펠러의 형상을 변경하는 것이 일반적으로 사용되며, 형상변화에 따른 입/출구압력, 유량, 임펠러의 토크 등의 성능특성을 파악하였다. MRF(Multiple Rotating Frame)기법 및 k-ù SST 난류 모델을 적용하여 회전 임펠러에 대한 수치해석을 수행하였으며, 형상의 변경에 따라 송풍기의 성능특성 및 최적화된 설계형상을 제안하였고, 압력측정실험을 통해 그 결과를 검증하였다.

The average sulfur content of crude oil is 2.2%. Coal is about 0.3 to 4.0 percent of the sulfur gases or particles being discharged into the atmosphere through the chimney as 1 to 2% SO3(Sulfur trioxide) and about 95% of the SO2 is reported. SO3 gas, which has many different causes of, as the combustion of sulfur containing fuel during the air due to the excess SO2 gas is oxidized to SO3 gas. Sulfur trioxide emitted from high sulfur heavy oil fired boiler caused white plume in stack and high temperature and cold end corrosion of facilities. So, in order to control sulfur trioxide concentration of Fuel gas in boiler, various of additives are used in other foreign. They are injected to Fuel Oil and consumed in boiler and reduce ash and the conversion rate of sulfur trioxide. In domestic, MgO compounds are used as additives but the total volume of them are made from other foreign company. In this study, MgO compounds were developed with liquid MgO compounds and field application was accomplished. The effect of newly developed chemicals and process were nearly equal to foreign products. In Consequent, the chemicals and process produced by newly developed technology can be substituted for foreign products and reduce the cost of plant operation.

본 연구에서는 수도수 중에서 Mg합금유전양극에 의한 연강재 온수보일러의 음극방식특성을 연구한 결과 다음과 같은 결론을 얻었다. 1) 온수보일러 관체의 개로전위에서나 전위가 높은 구간에서 모재의 부식전류밀도가 용접부위의 부식전류밀도보다 더 적게 배류된다. 2) 주조된 표면 그대로의 Mg합금 유전양극의 전류밀도는 주조된 표면을 연마한 상태의 Mg합금 유전양극의 전류밀도보다 더 많이 배류된다. 3) Mg합금 유전양극으로부터 거리가 멀어질수록 연강재 온수보일러의 음극방식전위는 높게 나타나고, 음극방식시간이 경과하면서 방식전위는 높게 나타나다가 6-10일 이후부터 방식전위는 안정되고 있다.

Heat transfer performance improvement by fin and groovs is studied for condensation of R-11 on integral-fin tubes. Eight tubes with trapczodially shaped integral-fins having fin density from 748 to 1654fpm(fin per meter) and 10, 30 grooves are tested. A plain tube having the same diameter as the finned tubes is also used for comparison. R-11 condensates at saturation state of 32 ℃ on the outside tube surface coded by inside water flow. All of test data are taken at steady state. The heat transfer loop is used for testing singe long tubes and cooling is pumped from a storage tank through filters and folwmeters to the horizontal test section where it is heated by steam condensing on the outside of the tubes. The pressure drop across the test section is measured by menas pressure gauge and manometer. The results obtained in this study is as follows : 1. Based on inside diameter and nominal inside area, overall heat transfer coefficients of finned tube are enhanced up to 1.6 ~ 3.7 times that of a plain tube at a constant Reynolds number. 2. Friction factors are up to 1.6 ~ 2.1 times those of plain tubes. 3. The constant pumping power ratio for the low integral-fin tubes increase directly with the effective area to the nominal area ratio, and with the effective area diameter ratio. 4. A tube having a fin density of 1299fpm and 30 grooves has the best heat transfer performance.

There is growing concern over the effects of global warning. In response, the power generation sector must consider a wider range of systems and fuels to generate power. One of the classes of solid fuels that is being increasingly developed is biomass. However, one of the most serious problems that biomass plants face is severe corrosion. To mitigate the problem, various approaches have been proposed in terms of additive utilization. This study is based on the results obtained during the co-combustion of wood chip and waste wood in a circulating fluidized bed boiler (CFBC boiler). The KCl concentration was reduced from 59.9 ppm to 3.9 ppm during the injection of ammonium sulfate, and NOx was reduced by 25.5 ppm from 30.6 ppm to 5.1 ppm. However, SOx increased by 110.2 ppm from 33.2 ppm to 143.4 ppm, and HCl increased by 71.5 ppm from 340.5 ppm to 412.0 ppm. Thus, we confirmed that the attitude of the superheater tube was reduced by 87 ~ 93%, and the injection of ammonium sulfate was effective in preventing high-temperature corrosion.

The emission of nitrogen oxides has a great environmental impact. It leads to Los Angeles type smog, and it recently has attracted attention as a source of ultrafine dust. The main sources of nitrogen oxides are internal combustion engines and industrial boilers. These emission sources are processes that are essential for human industrial activities, so the regulation of original use is impossible. Therefore, special control methods should be applied to reduce NOx emissions into the atmosphere. In this study, we investigated how the supply of ER and urea influences the removal of nitrogen oxides from SRF combustion boilers. Experimental results show that the removal efficiency of nitrogen oxides can be up to 80% under the conditions of ER 2.0 and a urea feed of 0.5 LPM.

In this study, the combustion characteristics were investigated based on the biodrying solid recovered fuel (SRF) in a 5 Ton/day scale combustion boiler. The composition of the combustion gas containing the biodrying SRF was analyzed, the particulate matter, and its HCl content was determined with the air pollutant process test method. Mass balance, carbon balance, and combustion efficiency were calculated according to the equivalence ratio (ER) method; the energy recovery efficiency of the combustion boiler was also analyzed. The overall combustion efficiency of the biodrying SRF was 97.3 % and the energy recovery efficiency was 80.2%.

부식 현상은 발전소 및 대규모 난방가동시설 등의 각종 산업 현장에서 해결해야할 중대한 문제 중 하나이다. 특히 보일러 시스템의 높은 가동 온도 조건은 부식의 주된 원인으로 이러한 고온 부식 현상을 억제하기 위한 다양한 재료 및 방법들에 대한 연구가 활발히 진행되고 있다. 본 연구에서 우리는 직접 개발한 세라믹 코팅을 현장 보일러 시스템에 적용하는 실험을 통해 보일러 가동조건에 따른 내부식성에 대해 고찰해보았다. 특히, 현장 보일러 시스템에 적용하는 연구를 통해 고온 환경에서의 내부식성 뿐만 아니라 연소 후 발생하는 각종 생성물에 의한 보일러 관 부착 현상에 대해서도 상대적으로 평가할 수 있었다. 또한, 세라믹 코팅의 내부식성에 대한 효과로 인해 발생하는 보일러 관의 수명연장효과(잔여 수명 분석)에 대해서도 정량적으로 분석하였다.

신재생 에너지의 활용 및 폐기물 순환을 통한 재활용에 주목하는 전세계적인 요구에 힘입어 바이오매스 및 생활환경 폐기물을 연료로 발전하는 SRF 발전에 대한 연구가 활발하게 진행되고 있다. 특히 화석연료의 고갈과 각종 폐기물의 증가로 SRF 발전에 대한 수요는 점차 증가할 것이라 예상된다. 다만, 정제된 화석연료의 사용 대신 각종 폐기물을 연로로 활용하기 때문에 이로 인해 발생하는 연소 생성물에 의해서 다양한 문제들이 발생되고 있다. 특히 보일러 시스템 내에서의 보일러 관에 각종 연소 생성물이 부착되는 파울링 현상은 연속 운전 시간 및 에너지 효율 측면에서 극복해야할 대표적 난제이다. 본 연구에서 우리는 현장에서 채취한 각종 소각재 및 파울링 현상으로 인해 발생하는 보일러 관 표면의 클링커에 대한 구성 물질 분석결과들을 통한 회귀분석과 동시에 시뮬레이션을 통해 각 구성 물질의 함량 변화에 따른 소각재 및 클링커의 녹는점 변화에 대해 분석하였다. 이를 통해 파울링 현상에 영향을 미치는 인자들을 구별하고 이에 따른 해결법을 제시하고자 한다.

In the past, the role of incineration facilities was mainly to reduce waste and stabilize disposed material. However, as a key aspect of waste management policy, the concept of “waste Minimization and sustainable resource circulation society” has become an issue, and the effective use of waste has been emphasized. As a result, to promote the recycling of wastes from January 1, 2018, the Framework Act on Resource Circulation has been implemented. In this study, estimation factors that can affect the increase of energy recovery are selected by reviewing the estimation method of industrial waste incineration facilities having a separate boiler; moreover, the effect of calculation factors on energy recovery was quantitatively evaluated. According to this study, when the heat loss, condensate temperature, and power consumption decrease by 10%, the energy recovery of the target facilities increase by 0.4% (0.22 ~ 0.63%), 1.09% (0.57 ~ 1.32%), and 1.16% (0.52 ~ 2.13%) on an average.

By the end of 2012, the recycled proportion of domestic waste tires was 287,330 ton (93.9%) of the amount of waste tires discharged (305,877 ton). The waste tires have been reused for heat supply, material recycling and other purposes; the proportions are 50.1%, 20.7% and 23.1%, respectively. In the case of heat supply, waste tires are supplied to cement kiln (104,105 ton, 68%), RDF manufacture facilities (47,530 ton, 31%) and incinerators (1,923 ton, 1%). Recently, there has been an increase in the use of waste tires at power generation facilities as an auxiliary fuel. Thus, physico-chemical analysis, such as proximate analysis, elemental analysis and calorific value analysis have been carried out to evaluate potential of waste tires as an auxiliary fuel in Korea. The LHV (Lower Heating Value) of waste tires is approximately 20% higher than that of coal, at an average of 8,489 kcal/kg (7,684 ~ 10,040 kcal/kg). Meanwhile, the sulfur content is approximately 1.5wt. %, and balance of plant (e.g. pipe line, boiler tube, etc.) may be corroded by the sulfur. However, this can be prevented by construction and supplementation with refractories. In this study, TDF (Tire Derived Fuel) produced from waste tires was co-combusted with coal, and applied to the CFB (Circulating Fluidized Bed) boiler, a commercial plant of 100 tons/day in Korea. It was combined with coal, ranging from 0 to 20wt. %. In order to determine the effect on human health and the environment, gas emission such as dioxin, NOx, SOx and so on, were continuously analyzed and monitored as well as the oxygen and carbon monoxide levels to check operational issues.

The synthetic gas obtained from the gasification of waste material becomes more important not only in waste reduction but also for the generation of clean energy directly applicable to industrial combustors firing LNG fuel without any major modification of the boiler system. Therefore, in this study, a systematic calculation was made for the turbulent reaction inside a conventional LNG combustor to determine the temperature distribution and fluid flow field. By doing this, the syngas obtained from gasification of combustible waste could be evaluated for the potential applicability of syngas as a substitute for LNG fuel in the industrial field. In this calculation, the ratio of the syngas amount to the LNG amount was fixed. That is, based on calorific value, 70% of the fuel was syngas and 30% was LNG. Since the calorific value of the syngas was different from that of LNG with a high energy density, the different volumetric flow rate was expected to give rise to a visible flow field change together with the local velocity. Thus, in this study, the swirl intensity and the inlet nozzle diameter were varied carefully in order to resolve the flow field and turbulence effects on the reaction characteristics of the co-burning flame. First of all, the calculation result of pure LNG combustion was made successfully as a reference and for evaluation of the code implementation. The results obtained from the numerical simulation of the burning of syngas in the LNG boiler could duplicate the combustion feature almost similar to that of 100% LNG fuels by changing the injection method of the syngas without any major change of the boiler system. The results suggested the high potential of syngas as an economic substitute for conventional LNG fuel.