Tomislav Skračić, MA Undergraduate English Course for MARINE ENGINEERS 5th Semester Essential reading: SPINČIĆ, A., An English Textbook For Marine Engineers 2, Pomorski fakultet, Rijeka 2009. LUZER, J., SPINČIĆ, A., Gramatička vježbenica engleskog jezika za pomorce, Pomorski fakultet, Rijeka 2003. Fuel injection & Efficient combustion DEVELOPMENT OF NEW TECHNOLOGIES FOR FULFILLING IMO REQUIREMENTS IMO requirements and other regulations on the reduction of exhaust emissions (ispušne emisije) and environment protection are becoming increasingly tighter (stroži) and the allowed limits are getting lower. IMO societies have laid down guidelines (odredila smjernice) for future limits on emission contents (ispušnih komponenti), taking into consideration different applications and exploitation conditions of marine engines. The trend is to completely eliminate pollutants. The world's leading engine manufacturers have developed technologies able to meet (zadovoljiti) the new requirements and regulations. Increasing the number of injectors, ACERT and slide-valve technologies, together with application of water-in-fuel emulsion (emulzija goriva s vodom), selective catalytic reduction (SCR selektivna katalička redukcija), and biodiesel fuels represent comprehensive and efficient solutions. Some of them are presented here. ACERT® technology. Caterpillar has developed the ACERT technology (Advance Combustion Emission Reduction Technology) that involves fuel delivery, electronics, air management (razvod zraka), and combustion management. One of the key breakthroughs (iskorak / proboj) in ACERT technology has been the development of fuel delivery into the combustion chamber through multiple injections (višestruko ubrizgavanje). The multiple-injection process introduces fuel into the combustion chamber in a number of precisely-controlled microbursts (mikro-ubrizgavanja). Injecting fuel in this way allows for precise shaping of the combustion cycle. A controller (an electronic unit) directs the injector system to deliver precise quantities of fuel at exactly the right time during combustion. In addition to enhanced combustion and fuel saving, the ACERT technology enables optimum performance, i.e. maximum output and efficiency with minimum emissions at a wide range of load and engine rating (širokom rasponu opterećenja i brzina vrtnje). It is one of the best and most comprehensive technologies aimed at reducing harmful emissions of air pollutants from vessels, and it represents one of the solutions to the existing and future IMO regulations on exhaust emissions. MAN B&W slide valve (injector). In order to reduce harmful emissions from their slow-speed engines, MAN B&W has launched a new slide-type valve for fuel injection. This valve type has minimised the risk of subsequent penetration (naknadni prodor) of fuel into the combustion chamber after the fuel injection. This directly results in reduction of emissions of carbon monoxide (CO) (ugljičnog monoksida) and volatile organic compounds (VOC) (štetnih organskih komponenti) as, in the engines featuring this type of valve, there is no incomplete combustion. In addition to the development of slide-type fuel valves, MAN B&W has also optimised the nozzle for achieving lower NOx emissions (emisija dušičnih oksida). Compared to conventional fuel valves and nozzles, in this way a 25% NOx reduction at 90% engine load has been achieved, with an increase in fuel consumption of only 1%. Likewise (također / isto tako), these engines have a reduced smoke emission. Slide valves fitted to MAN marine engines ensure optimised combustion and cleaner engines. Enhanced combustion decreases the amount of non-burnt hydrocarbons (neizgorenih ugljikovodika) (around 30%) and particulate matter (PM) (krutih čestica), which results in less smoke. Furthermore (nadalje), the piston top ends suffer less load and wear, resulting in minimum wear of the exhaust valve seats. Most importantly, the slide valve, i.e. the fuel valve nozzle, entirely complies (zadovoljava / u skladu je s) with the IMO requirements on NOx emissions reduction. Modified fuel injectors (courtesy of MAN B&W) EXERCISE 1 – Use the following words to complete the text: associated, costs, decrease, however, research, therefore. There has been some ____________ into increasing the number of injectors per cylinder. Increasing the number of injectors enables the combustion process to be better controlled and ____________ more efficient combustion. It has been reported that a ____________ in NOx from 30% is achievable, ____________ there is a considerable cost associated with the need to have additional injectors, piping and ____________ equipment. As well as additional equipment, a significant increase in maintenance ____________ can be expected. EXERCISE 2 – Answer the following questions: 1. Name some of the world's famous engine makers. 2. Name some technologies and applications aimed at 3. 4. 5. 6. 7. reducing harmful emissions from vessels. What harmful components do the exhaust emissions contain? What is the major drawback (mana) of increasing the number of injectors for achieving efficient combustion? How is enhanced combustion achieved by ACERT technology? How is incomplete combustion prevented in new MAN engines? Besides efficient combustion and meeting IMO requirements, name some other advantages of these new technologies. EXERCISE 3 – Translate into English: a) Proizvođači motora prisiljeni su razvijati nove tehnologije, b) c) d) e) za zadovoljavanje (for fulfilling / meeting) IMO propisa. MAN B&W je uveo klizne ubrizgače kao standardnu opremu (standard feature) svakog novog motora. Da bi se postigli bolji rezultati u smanjenju ispušnih emisija (exhaust emissions reduction), MAN razvijaja i sekundarne metode kao što su primjena emulzije goriva s vodom (water-in-fuel emulsion) i selektivna katalička redukcija (selective catalytic reduction). Standardni motor dozvoljava emulziju goriva s 20% vode pri punom opterećenju (at full load). SCR je trenutno najefikasnija metoda za smanjivanje emisije NOx-a, a smanjenje iznosi 85%-95%. EXERCISE 3 – Translate into English: f) Urea, reducirajuće sredstvo (means of reduction), se ubrizgava u ispušne plinove pri temperaturi od 290-450°C. g) Prije ulaska u Područje kontroliranih emisija (Emission Control Area), količina goriva u svakom tanku, kao i (as well as) datum, vrijeme i pozicija broda moraju se unijeti (be recorded) u Knjigu o uljima (Oil Record Book). h) Optimalno izgaranje rezultira smanjenjem emisija ugljičnog monoksida (CO), štetnih organskih komponenti (VOC), dušičnih oksida (NOx), neizgorenih ugljikovodika (non-burnt hydrocarbons) i krutih čestica (particulate matter – PM). i) Kod teških dizelskih goriva, moguća je čista emulzija vode i goriva, dok kod benzina treba primijenjivati emulgatore (emulsifier) kao što su biljni proteini (plant proteins).