THE OPTIMIZATION OF THE STEAM PLANT BY MEANS OF AN ENGINE ROOM SIMULATOR

U radu je prikazano optimiranje parnoturbinskog pogonskog postrojenja na brodu za prijevoz ukapljenog prirodnog plina. Izvršena je analiza pogonskih radnih parametara te su na simulatoru brodske strojarnice simulirane situacije koje utječu na iskoristivost postrojenja. Izvršene simulacije na simulatoru LNG broda omogućile su praćenje promjene radnih parametara pri pojavi neželjenih i neočekivanih stanja za koje postoji vjerojatnost pojavljivanja unutar funkcionalnog realnog sustava. Na taj način je moguće bolje dijagnosticirati greške unutar realnog sustava te odrediti optimalno ponašanje pojedinih elemenata sustava. Kod generatora pare analiziran je utjecaj pojave čađe na cijevima zagrijača vode i pregrijača pare na potrošnju goriva, te utjecaj izgaranja različitih goriva na emisiju NOx. Kod parne turbine analiziran je utjecaj istrošenosti odrivnog ležaja turbine i istrošenosti lopatica niskotlačne turbine na snagu, aksijalni pomak i na pojavu vibracija turbine. Dobiveni rezultati pokazuju da primjena simulatora može poslužiti brodarskim kompanijama i pomorskim edukacijskim ustanovama za uvježbavanje pomoraca i studenata za rad u različitim okolnostima te za brzo i učinkovito reagiranje u kritičnim situacijama.The optimization of the steam propulsion plant on LNG tankers is dealt with in this paper. The operational parameter analysis was performed and the situations influencing the plant efficiency were simulated on the engine room simulator. The performed simulations on the LNG simulator module enabled monitoring of the operational parameters change in undesirable and unexpected conditions for which there is a probability to occur within the operational system. In such a way an enhanced diagnostics of failures within a real system and the determination of the optimal performance of individual components are possible. The boiler analysis has concentrated not only on the influence of soot deposit on the economizer and superheater piping to the fuel consumption but also on the influence of burning different fuels to NOx emission. Another analysis has been carried out in the main turbine in which the influence of worn out thrust bearing and low-pressure turbine blades to the turbine output, axial displacement and vibrations was analysed. The results have shown that the simulator can serve the shipping companies and maritime educational institutions to train the students and seafarers for working in various situations and to prepare them to respond to emergencies promptly and efficiently

Computerized Planned Maintenance System Software Models

Classification societies certify computerized planned maintenance systems, which have to comply with ISM, IMO and IASC standards. This paper aims at presenting standard requirements and a short history outlook for three planned maintenance software solutions: Amos, Bassnet and Titan. Software packages are scanned through their modules and features. The maintenance module overview, with all related features, is selected for three software solutions where the maintenance module is the only module which is related to the Class requirements. The aim of this paper is to discuss the advantage and disadvantage of each software separately and their application in the shipping industry

THE ANALYSIS OF THE MARINE TURBOGENERATOR INSTALLATION COST EFFECTIVENESS

U radu su prikazani rezultati provedene simulacije i istraživanja isplativosti ugradnje turbogeneratora na brod. Analiza je provedena primjenom NOR Controlovog simulatora za simulaciju brodskog postrojenja tankera za prijevoz sirove nafte. Simulirana je proizvodnja električne energije s turbogeneratorom ili s dizelskim generatorom. Analiza početnih investicijskih troškova provedena je anketom s proizvođačem brodskih generatora pare te s dobavljačima turbo i dizelskih generatora pri čemu su se koristile trenutne cijene teškog i lakog dizelskog goriva na svjetskom tržištu. Izračunate su uštede u slučaju kada se za proizvodnju električne energije koristi turbogenerator u paralelnom radu s osovinskim generatorom. Rezultati istraživanja pokazuju značajne uštede i neupitnost isplativosti ugradnje jednog takvog uređaja na brod, kao i opravdanost njegovog maksimalnog korištenja, ako je na brodu instaliran.Results of the simulation of and research into the cost effectiveness of mounting the turbogenerator on board a ship are dealt with in this paper. The analysis was performed by using the Konsberg NorControl crude oil carrier engine room plant, where the situations of the electrical power generation with turbo generator as well as with diesel generator were simulated. The initial cost analysis was carried out by a questionnaire with the exhaust gas boilers manufacturers, turbo generator and diesel generator suppliers. For the bunker price calculations, the present heavy fuel oil and diesel oil prices on the world market were used. The fuel savings were calculated by comparing the electrical power production situation with two diesel generators and the situation when a turbo generator was paralleled with a shaft generator. The results were additionally verified by using the computer aided program for the economical prediction of the project. The research results have arguably confirmed the thesis that mounting the turbogenerator on board a ship has great benefits and, if it is already mounted, it should be used as much as possible. The research results also confirm a great influence of planning the bunkering – choosing the bunkering ports, as well as the importance of the engine plant optimization and exploitation optimization on the final exploitation costs

Impact of ship exhaust gases emission on human health

The protection of the environment in maritime industry has always been of major concern. Nowadays emission sources from ships are a threat not only to the environment but also to human health, especially in ports and coastal areas. Diesel engine exhaust contains several pollutants that are harmful such as: nitrogen oxides, carbon dioxide, sulphur oxides and particulate matter. Exposure to diesel exhaust may have the consequences of premature lung cancer and cardiovascular diseases. It may also cause coughs, headaches, nausea and an increase in the frequency of asthma attacks. The microscopic particles from exhausts can easily penetrate deep into our lungs as we breathe and inhale. An estimate of emission gases from international marine traffic for the port of Zadar was calculated for this paper. The focus of research was on the particulate matter (PM) emission in the passenger port and cargo port of Zadar. This research includes the overall marine traffic from passenger and cargo terminals over one year. Furthermore, some recommendations for reducing emissions in ports are emphasized and explained

Maintenance Interval Adjustment Based on the Experience, Case Study of Marine Air Compressor System

The paper presents the initial case of a research of analysing maintenance interval adjustment in the shipping industry. This case is an example of the adjustment of the maintenance interval carried out by ship’s crew on starting air compressor system. The example is found and followed through the records in the computerized Planned Maintenance System. Maintenance interval adjustment proposal and actual adjustment were carried out based on user’s experience, after rechecking maintenance data and actual machinery condition, without theoretical approach or analysis. That process created new maintenance plan which is in use on the system for past ten years. Missing actions in the process, i.e. theoretical analysis of the initial and modified maintenance, are performed using the MA-CAD method with a modified reliability testing and are described in the paper. Results obtained by the theoretical analysis are compared with the requested and performed modification of the Maintenance Plan and a conclusion about performed action has been derived

Steam Flow Pressure Reduction Valve Mass Flow Calculation

In this paper an analysis of the three different calculation methods for the steam mass flow through the linear pressure reduction valve is presented. Two different makers developed their own mass flow calculation method while one is following recommendation as per ISO standard calculation guidance. All three methods were varied and compared. For calculation model a superheated steam reduction valve was taken, which is reducing superheated steam pressure from 6 to 2 MPa, with fixed Kv value and with variations of the inlet superheated steam temperature from 310 to 280 °C

Thermodynamic analysis of marine steam power plant pressure reduction valves

The paper presents a thermodynamic analysis of pressure reduction valves from a marine steam power plant that operates on conventional LNG carriers. The analysis refers to six condensate and superheated steam pressure reduction valves. Based on the exploitation data, the calculation involves the energy/exergy flow streams as well as the exergy efficiency and exergy destruction of each pressure reduction valve. The analysis also included the influence of changes in the ambient temperature on the efficiency and destruction of each valve. Total energy and exergy fluid flow streams through each valve showed the same trends. The superheated steam pressure reduction valves showed a lower average exergy destruction rate and higher average exergy efficiency compared with the water/condensate ones. Increase in the ambient temperature resulted in a continuous increase in the exergy destruction rate and a continuous decrease in exergy efficiency in all the observed pressure reduction valves. Pressure reduction valves of high exergy destruction rate and low exergy efficiency are notably influenced by changes in the ambient temperature