Diesel Plant Research Articles

Cleaning diesel plant exhaust gases

Results are given on cleaning diesel exhaust gases by means of a system containing ceramic filters, which show that high-temperature filtration provides effective cleaning.

ＬＮＧ船１０ＭＰａ蒸気タービンプラントの水質管理について

The steam turbine plant is well known, good for reliability, but not good for specific fuel consumption to the diesel plant. As the demand for LNG carriers and the requirements for fuel saving are increasing year and year, more efficient steam plant is being required. In response to this requirement, a new steam plant, which adopts the reheat cycle with the steam pressure of 10 MPa, has been developed. The adoption of higher pressure steam would require the more sophisticated water quality control so that its reliability could be maintained at high level as same with the conventional 6MPa plants. This paper considers the appropriate water quality control criteria and phosphate treatment for the new plant, and makes it clear that a quite different boiler water treatment is needed from the treatment of conventional plant.

Rhizosphere Microbial Activity During Phytoremediation of Diesel-Contaminated Soil

To know microbial activity and diesel-removal efficiency influencing through plant roots, we examined the effect of the rhizosphere on phytoremediation of diesel-contaminated soils by alfalfa (Medicago sativa L.). Pots were treated with and without diesel and allowed to stabilize for 7 weeks, at which time four experimental/control groups were prepared: (1) planted diesel-contaminated soil, (2) unplanted diesel-contaminated soil, (3) planted uncontaminated soil, and (4) unplanted uncontaminated soil. Samples of rhizosphere and bulk soils were separately taken from all planted pots. After 7 weeks of alfalfa growth from seeds, the removal efficiencies in rhizosphere and bulk soil samples were 82.5% and 36.5∼ 59.4%, respectively. The total microbial activity was highest in diesel-contaminated rhizosphere soils. Significantly more culturable soil bacteria and hydrocarbon-degraders were found in diesel-contaminated rhizosphere soil versus unplanted and uncontaminated bulk soil, with a greater increase seen in hydrocarbon-degraders (172-fold) versus general soil bacteria (14-fold). DGGE (Denaturing Gel Gradient Electrophoresis) analysis revealed that the bacterial community structure was most highly influenced by the combined presence of diesel contamination and plant roots (39.13% similarity compared to the control), but that diesel contamination alone had a higher influence (42.31% similarity compared to the control) than the rhizosphere (50.00% similarity compared to the control). Sequence analysis and BLAST searches revealed that all samples were dominated by members of α -, γ -, δ - and ε -proteobacteria, and Chloroflexi. The rhizosphere samples additionally contained novel dominant members of α -proteobacteria and Cytophaga-Flexibacter-Bacteroides, while the diesel samples contained additional dominant α -proteobacteria and the rhizosphere plus diesel samples contained other ε -proteobacteria. Collectively, these findings indicate that the presence of plant roots (i.e., a rhizosphere) had a greater effect on bacterial activity in diesel contamination than did the absence of diesel contamination, whereas diesel contamination had a greater effect on bacterial community structure. These novel findings provide new insight into the mechanisms of phytoremediation.

Water Fraction Measurement in Marine Fuel Emulsions

The proposal, from the International Maritime Organisation (IMO), to limit further the emissions from marine diesel engines came into effect in May 2005. This has considerable consequence for the management and operation of ship diesel plant. One method that has been shown to limit the emissions of NOx is the addition of quantities of water as an emulsion into the heavy fuel oil (HFO) before it is injected into the burners. This reduces the peak combustion temperature, improves atomization of the diesel fuel, and can reduce emissions by as much as 30 per cent. A key component for an efficient and cost-effective system is a method to monitor the water content to an accuracy sufficient to allow the mix to be adjusted to meet the needs of the varying engine loads. This paper briefly presents the environmental, legislative, and technical background. The principle aim is, however, to describe the experimental work examining the application of an in-line optical sensor. Laboratory tests on HFO, having a room temperature viscosity of 180 cSt, were undertaken at two nominal temperatures, 80 and 130°. These tests provide empirical evidence that an in-line optical monitor could determine water fraction within the emulsion to the accuracy requirement (better than 3 per cent) and over the operational water content range (15-33 per cent water to oil). A hypothesis is presented to explain the changes in the optical scattering characteristics of the oil/water emulsion with water content. Additional results are presented that demonstrate the use of two commercial viscometers to quantify the oil/water fraction. It was concluded that the measurement of emulsion viscosity can be related to water fraction but that the current instruments do not have the required resolution and have serious limitations due to their temperature sensitivity. A key requirement for further work is that the scattering properties of the emulsion be investigated in greater detail. In particular a test must be undertaken at temperatures in the region of 170°. Also, the instrument must be developed to cope with the wide variety of diesel fuels that a ship may take on at bunkering facilities around the world.

Susceptibility and exposure biomarkers in people exposed to PAHs from diesel exhaust

Xenobiotic metabolizing enzymes, especially CYP1A1 and GSTM1, are involved in the activation and conjugation of PAHs and are controlled by polymorphic genes. PAHs released from diesel emissions in many cities of the world, especially in developing countries, contribute significantly to the toxic effects of airborne inhalable particles. We have evaluated the gene-environment interaction in Santiago of Chile, studying the contribution of CYP1A1 and GSTM1 polymorphisms on 1-OH-P urinary levels used as the PAHs exposure biomarker. The study was performed on 59 diesel exposed (38 diesel revision workers and 21 subjects working in an urban area as established street vendors) and 44 non-exposed subjects living in a rural area. The 1-OH-P urinary levels of the urban ( P=0.043) and rural ( P=0.040) populations showed, without considering the genotypes, significant differences between smokers and non-smokers, but no significant differences were found between smokers and non-smokers among the diesel plant workers ( P=0.33). Non-smoking subjects of the diesel plants and the urban area showed similar 1-OHP levels ( P=0.466) which were significantly higher than those of the subjects living in the rural area ( P<0.05). When 1-OH-P levels were related with genotypes, an association was observed for the CYP1A1*2A genotype, so that the diesel-exposed workers carrying the CYP1A1*2A allele showed significantly higher 1-OH-P levels than the subjects from the rural area with the same genotype ( P=0.008). On the other hand, there was no significant correlation between urinary 1-OH-P levels and GSTM1 null genotype, although higher levels of the urinary metabolite were found in individuals carrying the combined CYP1A1*2A and GSTM1 null genotype ( P=0.055). These results may suggest an association between levels of the exposure biomarker 1-OH-P and presence of the CYP1A1*2A genotype, a potential genetic susceptibility biomarker which might be useful in identifying individuals at higher risk among people exposed to high PAH levels in diesel exhaust.

Decision Method of the Optimal Number of Maintenance Crew on Diesel Plant

Generally, there are some relations of the queue that are occurred while the maintenance work and the recovering work. Therefore, it is able to calculated increase or decrease situation that is waiting time, waiting number of cases and occurrence ratio by using a queue procession. Furthermore, it's gotten the optimal number of maintenance person by making the occurrence situation. Engine failure in a ship can be regarded as exponential arrival model in random failure period. Also it's conceived that the distribution in recovery time complies with random Poisson or Erlang distribution. Recovering work data are calculated with a repair rate from a man-hour in terms of the kind of maintenance and queue simulation model. It was constructed by using queue processions and simulation programs. Finally, it's found out the number of optimal maintenance personnel concretely by it.

タービンプラントの信頼性の現状と対策 (第二報)

According to analized the turbine and diesel plant reliability, we were able to picked up some problems to make large amount of Failure Rate or Manning Index.1) Mainly trouble of auxiliary equipment caused by low grade fuel. The most affected equipment is the fuel purifier and also following equipment affected too, Diesel Plant: LO purifier, Auxiliary boiler, DIG, M/E, FO filter LO filter, Incinerator. Turbine Plant: Main boiler burning equip.2) Automatic equipment failures occurred 18 days each and need 8.5 MH. MI and FR are occupied approximately 1/3 of whole plant. These are judged ghost & unknowm reason that is about 50 to 70%.3) Turbine plant are needed much recovery time to maintenance for cooling down the steam line, move the big mass of heavy weight and valve operate for complex construction. Mainly cause are aging, defective fitting and poor materials.So, we should make some counter plan to reduce the Failure Rate and Mannind Index as follows.a) To be developed fully automatic treatment system of fuel and waist oil (FWTS) to reduce a failure ratio of fuel and LO purifier, auxiliary boiler, etc.b) To be developed Total Distributed Control System (TDCS) with back up controller to increasing continuous running of control equipment and quickly recoverling.c) To be set the central fresh water cooling system (CCFW) to reduced a pipe corrosion and Maintenance man hours.

タービンプラントの信頼性の現状と対策 (第一報)

Reliability of turbine plants has not been investigated since 1980's because turbine plants have not been installed due to more fuel consumption than those of diesel plants. However steam turbine ships are gradually increasing since the LNG vessels began to be constructed. This report investigates alarm and failure situations of turbine ships based on data gathered by “Committee on Ship Reliability Investigation (CSRI) ” and actual field data of LNG turbine ships compared with reliability data of diesel ships on same period. Also this report refers to future design of turbine plant for reliability improvement. Among analysis results of the turbine and diesel plant reliability, authors picked up some problems which increase Failure Rate or Manning Index.1) Major trouble of auxiliary equipment were caused by low grade fuel. The equipment which is most affected is the fuel purifier.2) Automatic equipment failures occurred every 18 days and needed 8.5 MH. MI and FR of those failures occupied approximately 1/3 of whole plant. About 50 to 70% of reasons are judged to be ghost or the unknown.3) Maintenance works of turbine plant required much time for preparation works like cooling down of steam line, transfer of big mass or valve operation of complex piping system.

Treatment of gas from a diesel plant

Treatment of gas from a diesel plant

マルチメディア環境における教育用ディーゼルプラントシミュレータ

Nowadays, a multi-media computer system has been developed.The computer aided instruction system has been widely applied but it is required to use multi-media data for the system. This paper describes the simulator and the guide program for marine diesel plant training by use of multi-media interface. Especially, as the graphical user interface of the computer is very important to use the system effectively, it has been realized in the simulator and the guide program. Hence, a simplified math-model is selected for the use. The model of the diesel engine is very useful for training and such approach is very effective for the training simulator of complicated plants.

Probabilistic evaluation of the performance of wind-diesel energy systems

A probabilistic method for predicting the economic performance and reliability of autonomous energy systems, consisting of diesel generators and fixed pitch wind generators, is described. The method uses the duration curves of the load and the wind speed. Several constraints are applied among them the most significant are the following: load and wind speed are statistically independent; and there is a limitation of wind power penetration due to load and minimum diesel plant output. The quantities that are computed are: wind and diesel energy production; diesel fuel consumption; loss of load probability; and expected unserved energy. Results are presented for two Greek islands. >

A probabilistic method for the evaluation of the performance of wind-diesel energy systems

The method takes into account the constraint that the wind generation must not exceed a certain percentage of the system load, which is imposed for reliability reasons. The method efficiently computes the statistics of the wind generation and the diesel plant loading based on the statistics of the wind speed and the system load demand. The performance of the method is demonstrated with computational results. An example of obtaining the optimum wind penetration for an existing diesel system is presented.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Economic analysis of a husk-fueled gasifier power plant at a rice mill in Africa

A Chinese-built gasifier power plant fueled with rice husks has been installed at the Molodo rice mill in Mali under a cooperative program of the governments of the Federal Republic of Germany, the Republic of Mali, and the People's Republic of China. A report by the German Agency for Technical Cooperation (GTZ) compared the cost of electric power for the Molodo rice mill from (a) a diesel power plant consisting of two 170 kVA generating sets and (b) the Chinese gasifier power plant. The total cost of energy from the gasifier plant was only slightly more than half that from the diesel plant. Despite the high capital cost of the gasifier system, GTZ concluded that the increased investment costs of the gasifier power plant could be recovered in less than four years.

訓練用ディーゼルプラントシミュレータ

The subjest equipment has been developed for seamen's training in response to learn the high level techniquefor the highly modernized ship which increased recently.The process values of diesel plant for the equipment has been simulated based on energy's flow on full containership“JAPAN ALLIANCE”, so that trainees would feel to be in the real engine control room.In this paper, the outline of the simulator is introduced.

Performance monitoring of diesel electricity generation

The paper describes the characteristics of diesel generation plant and discusses the role of diesel generation in the context of bulk supply of electricity. The specific operational and maintenance aspects of diesel generation are presented and the need for the development of aids to routine maintenance are discussed. One technique for monitoring the performance of diesel plant is described and results are given from tests carried out in Stornoway power station on the island of Lewis.

Medium-Speed Diesel Engines: Part I—Design Trends and the Use of Residual/Blended Fuels

Fuel costs can exceed 50 percent of the total diesel plant’s operational expenditures. To reduce fuel costs, medium-speed engines are now available with improved fuel consumption and ability to burn residual fuels. Part I of this paper reviews these engine and design changes needed for both improved fuel consumption and the ability to burn poorer quality fuels. Characteristics of these fuels and international fuel specifications are discussed. Ignition quality of residual fuels by a modified ASTM D 613 procedure are presented and correlation shown to calculated diesel index and calculated carbon aromaticity index (CCAI). Residual fuel ignition delay effects on combustion pressure rise, fuel consumption, and piston temperature in a laboratory single-cylinder diesel engine are shown.

Medium-Speed Diesel Engines: Part II—Lubricants, Their Characteristics and Evaluation

Fuel costs can exceed 50 percent of the total diesel plant’s operational expenditures. To reduce fuel costs, medium-speed engines are now available with improved fuel consumption and ability to burn residual fuels. Part II of this paper reviews characteristics of lubricants suitable for use with distillate, residual, and blended fiels in medium-speed engines. Examples are shown of how lubricants and their additives control engine wear, deposits, and oxidation, and how fuel consumption is affected by viscosity. Control of insolubles and the purification of used lubricants are discussed.

超音波ホモジナイザによる乳化燃料油の生成と特性

The reduction in fuel consumption and NOxemission have been confirmed with burning of emulsified fuels in diesel and boiler plant so far. Fuel savings from four to seven per cent have been achieved, when burning water-in-heavy oil emulsions in marine diesel engines.In the evaluations of emulsified fuel combustion, the following parameters should have been considered: water content, particle size, distribution, stability, viscosity, specific gravity. These fundamental data with emulsified fuel have been lacked.Thus investigations have been given to these parameters which affect conditions of combustion.

An Updated Analysis of Fuel Consumption: Steam and Diesel

Each element of the total fuel consumption of typical steam plants is presented, starting with the turbine propulsion cycle performance, then building up to the standard all-purpose fuel consumption rate normally reported. The method of presentation illustrates the contribution of each element to the whole, including consideration of transmission loss, boiler efficiency, fluid pumping power, electrical load, etc. Similarly, diesel plant performance is represented in as duplicate a format as possible, starting with the test-bed performance of the engine and then considering in-service fuel, lube oil, electrical load, etc. By presenting both plants in the manner described, from approximately 40 to 100 percent power, the point is made that the disparity between steam and diesel plant performance is less than normally assumed, and, in certain applications, nonexistent. As a corollary, the part-load performance of the two plants is shown to be remarkably similar. The paper is divided into four parts for ease of reference:summary and conclusions,steam plant,diesel plant, andcomparisons.

遊星歯車式減速装置を有するギャードディーゼルのねじり振動

Recently, the geared diesel plant has been gaining its position in the field of marine propulsion system because of its energy saving characteristics. Among several kinds of reduction gear, the epicyclic gear type is fairly compact and light and has been increasing its share of sales. Our company has been producing the IMT type epicyclic reduction gear, of which the basic technical patent is held by Toyo Seimitsu Zoki. This type of reduction gear is equipped with special“equalizer pins” to support the ring gear. The equalizer pin is flexible against the transmitted torque and because of this flexibility, the torsional vibration system must be specially analyzed so that the flexibility is fully represented in the calculation. In this paper, the theoretical analysis of such a system is given, then the calculation and measurement results are also shown on one particular case as an example.