INTERNAL COMBUSTION ENGINES University of San Carlos School of Engineering School of Mechanical Engineering Internal Combustion Engines Alvaro Avila
THE USE OF GASEOUS FUEL IN A DIESEL ENGINE, ADVANTAGES AND DISADVANTAGES GROUP # 1 INTERNAL COMBUSTION ENGINES GENERAL OBJECTIVE
To know the performance of Internal Combustion Engines by gaseous fuel, as wel l as analyze the advantages and disadvantages that brings the gas fuel use, chec k the operation of the through parts of a MCI. SPECIFIC OBJECTIVES
Analyze the advantages and disadvantages of gaseous fuel. An economic evaluation of gaseous fuel. the process for use a
Be aware of the global energy situation. nd applications of gas fuels.
Get an overview of the properties a
GROUP # 1 INTERNAL COMBUSTION ENGINES GAS DIESEL ENGINES Gaseous fuels are called hydrocarbons to natural and manufactured exclusively fo r use as fuel, and those obtained as a byproduct in certain industrial processes and can be harvested for fuel. The composition of these varies depending on the origin of the same, but the components can be classified can be classified into combustible gases (CO, H2, (HC)) and other gases (N2, CO2, O2). Gaseous fuels a re classified as natural gas fuels Gaseous fuels manufactured
We want to know the percentage of components that make up the gas. These are use d to the same procedures as for the analysis of combustion gases. There is anoth er classification of gaseous fuels with respect to their degree of interchangeab ility. This allows us to classify families gaseous fuels, which are three: 1st,2nd, 3rd. FEATURES AND BENEFITS OF GASEOUS FUELS The calorific value, one of the most important properties of a fuel, is expresse d for gaseous fuels per unit volume in normal conditions. The calorific value wi ll vary greatly depending on the type of gas that we are driving, and therefore, depending on the components of the fuel we're driving. Non-combustible componen ts of a fuel will lower the heat efficiency of combustion. However, despite this
, sometimes a GROUP # 1 INTERNAL COMBUSTION ENGINES lower quality fuel but is a byproduct of an industrial process may be more advan tageous financially. We recall that there are two kinds of calorific value:
Calorific value, which is released to perform the combustion of a unit volume of gas Calorific Value, which is the same as above, but without taking into accoun t the heat of condensation of water produced in combustion.
Calorific units are kcal/m3; Btu/ft3, Cal / L The unit volume can be: Nm3: Under normal conditions: Volume measured PN: 1 atm TN: 0 º C Sm3: In standard conditi ons: Volume measured PS : 1 atm TS: 15.6 º C To express the energy released in c ombustion is used TERMS ENDS = 2500 cal for calculating the calorific value of g aseous fuel is necessary to know the composition of the (corporción components). Knowing the heats of combustion of the individual components is relatively simp le to calculate the calorific value of fuel: Another important property of fuel is the specific heat. It is defined as the am ount of heat required for the unit mass of gas increases its temperature 1 ° C. Units are cal / g º C; Kcal / kg º C Btu / lb ° F. But the truth is that with in creasing temperature there is a dilation, is therefore defined the following spe cific heats at constant volume specific heat (Cv) Specific heat at constant pr essure (Cp)
GROUP # 1 INTERNAL COMBUSTION ENGINES Cv is less than Cp, because you have to take into account the expansion work to be performed. There is a relationship between these two values: Cp / Cv Monatomi c Gas: 1.67 diatomic gas: 1.40 triatomic Gas: 1.33 Another property of gaseous f uels is the viscosity. As the temperature increases the viscosity. There are two types of viscosities, kinematics and dynamics. Another property of gaseous fuel s is the index of WABBA (W). Also corrected WABBA index, defined as the ratio be tween the PCS and the root of the relative density: The index takes into account fixed WABBA hydrocarbons heavier than CH4, CO2 and other: Wc = K1 · K2 · W K1 and K2 depend on the family of fuel and CO2 content, CO and O2.Also the effect of hydrocarbons heavier than methane A useful feature of gaseous fuel is called combustion potential, which is defined as follows: a: factor characteristic of the flame speed GROUP # 1 INTERNAL COMBUSTION ENGINES Another important feature of fuels is their interchangeability. It is said that two gases are interchangeable when distributed under the same pressure on the sa me network and without regulatory changes produce the same results of combustion (the same heat flux) and the flame has the same identical position and the same behavior as well. It is impossible in reality that two gases are interchangeabl e to 100%, what is that actually looks almost be interchangeable. There are some
diagrams of exchanges in which one can quickly see if a gas is interchangeable with another (Delbourg diagrams) COMBUSTION OF A FUEL GAS In the combustion of a gaseous fuel is easy to deduce that the mixing with the o xidant is performed in an easy manner. The manner in which combustion takes plac e basically is the same as for a solid or liquid fuel. Is still used, in general , the air as oxidizer, but sometimes uses oxygen. It is necessary in this case t he use of burners, which is where it will produce the fuel mixture combustion. C ombustion is rapid but not instantaneous. Time is needed to facilitate the react ion mixture. Combustion is, as we know, an oxidation reaction. The flame is the source of heat for this reaction. In any combustion process are three conditions that must be met: 1) To which can be initiated and propagate combustion, it is necessary that both the fuel and oxidizer are mixed in certain proportion and th e temperature of the mixture is higher than locally flashpoint 2) To maintain co mbustion must occur to products originating from the combustion to evacuate as t hey occur The power of the oxidizer and fuel is such that the conditions laid down so far (1)
GROUP # 1 INTERNAL COMBUSTION ENGINES 3) For the combustion takes place in good condition must be satisfied that: The air used in combustion is that corresponding to complete combustion without exce ss air = air minimal air used There should be a given turbulence and a certain time
FEATURES OF THE COMBUSTION OF GASES Ignition temperature: ignition temperature is the lowest temperature that can be initiated and propagated at a point of combustion air mixture gas. The self-ign ition of a gas-air mixture occurs about 650-700 º C. Flammability Limits: We u nderstand these as percentages of air and gas which have a mixture of both so yo u can start and spread the combustion of the mixture. It is usually expressed as a percentage of combustible gas in the mixture. Both the excess fuel and oxidiz ers are harmful to the combustion outside the flammability limits Burning velocity: The speed of propagation of a stable flame
PARAMETERS OF INTEREST IN THE COMBUSTION OF GASES: THEORETICAL AIR POWER VORO O The amount of air necessary to ensure the combustion of 1 m of gas. Usually expr essed in normal m3 of gas normal aire/m3 3 CAN SMOKE (SMOKE OR COMBUSTION GASES) GROUP # 1 INTERNAL COMBUSTION ENGINES Joint Products in gas obtained in the combustion process. This is the volume exp ressed in C / N combustion gases obtained in the complete combustion of 1 Nm3 of gas associated with a quantity of air equal to the theoretical. Can be distingu ished: dry Smokes: Not water vapor wet Smoke: Considered the water vapor
They are expressed in normal gas humos/Nm3 nm2
CONTENTS OF EXCESS AIR A theoretical combustion air is impossible, so it is necessary in practice an ex cess of air, which is regulated by the rate of supply (which is the rate of exce ss air or something similar). Could be incomplete combustion, unburned gas to al ways (will never appear unburned solids). THEORETICAL TEMPERATURE COMBUSTION That temperature combustion products reach if all the heat generated in the samp le could be used in heating. This is impossible for heat losses in the installat ion. Enriching the oxygen content is possible to increase the current temperatur e of combustion to a certain limit. The hardware of the combustion gases are fue l burners. The burner is the body designed to produce the flame.It does this by connecting the necessary amounts of air and gas to the combustion takes place. The burner should regulate a number of areas, including: The air-gas mixture. It is adequate at all times flows of air and gas flame stab ility Dimensions and shape of the flame. This is done to adjust the flame to the combustion site. Radiation power of the flame at a given time GROUP # 1 INTERNAL COMBUSTION ENGINES The burners can be classified by the number or type of fuel with which they work , or also by the mode of operation. NUMBER OR TYPE OF FUEL Multigas: Work with various gases at once Mixed: They can work with different types of fuel, but not both simultaneously March: They burn both gas and other fuels (liquid or solid) March alternative: They can only burn a given fuel ty pe
OPERATING MODE Atmosphere: They have called short, low pressure, air enters the place with some fans Pressure: Pressure of up to 3 atm Boca Radiant: The entrance of the mixing is carried out through a nozzle of a sp ecial refractory material is heated to incandescence during operation, which fac ilitates the combustion of gases. COMBUSTION CALCULATIONS GROUP # 1 INTERNAL COMBUSTION ENGINES The combustion calculations are similar to those already seen. The calculations are to be provided in volume. If you're burning a gas mixture, each has an indep endent equation. ADVANTAGES OF GASEOUS FUELS
Easy to handle and transport via pipelines have no ashes or foreign matter from the combustion control is much easier, allowing us to maintain the temperature o f combustion even with variable demands Ability to regulate the furnace atmosphe re to get us as reducing atmospheres Possible appropriate heat regenerative and recuperative gas, thus raising the temperature of combustion, and therefore, inc reasing the thermal efficiency. Come or tend to come from low-quality solid fuel s, so we can give better use of such fuels is possible to determine its exact co mposition, making it possible to determine its calorific value quite well. With the same heat transfer, the flame that produces a gaseous fuel is shorter than t hat creates a solid or a liquid fuel. GASIFICATION OF SOLID FUELS Gasification is the conversion of carbonaceous material in any gas through the r eaction of O2 incandescent coal, water vapor, CO, SO2. This causes us a set of p roducts in state gas composition and properties depend on the nature of the gasi fying agent that we are using in the process. The gasifying agent is going to co nstrain the use of the product as fuel or gas as feedstock in other chemical pro cess above. In principle all are suitable for gasifying coal. Aerating are usual ly products that have no use in coke ovens. We are interested in processes where combustible gas is obtained. GROUP # 1 INTERNAL COMBUSTION ENGINES GASIFICATION WITH WATER VAPOR Thus we get gas or water gas blue (this name is because of the color of the flam e, blue, characteristic of the combustion of CO). The main reaction that takes p lace is: C (S) + H2O + 30 Kcal This is an endothermic reaction has a blue gas ca lorific value of 2580/2670 kcal/m3 to PTS (standard temperature and pressure) Th is represents 60-80 % of coal PCS. The yield from gasification is defined as the ratio between the PC and PCS gas coal which proceeds, ie CO + H2 The gas is used as fuel water is often more advantageous than direct coal combus tion. Using water gas is obtained:
Improve the mixture fuel / oxidizer, thus improving control of combustion, and a lso does that for complete combustion is required additional air fewer higher te mperatures are obtained, because the heat generated is used much better We can p reheat the fuel and oxidizer while no SO2 in the combustion ash or unburned No solid
DETAILS BELOW ARE SOME OF THE "PRO" AND "AGAINST" THE DIESEL ENGINES GAS V
Fuel consumption (Diesel Advantage) GROUP # 1 INTERNAL COMBUSTION ENGINES
There is more energy (BTU) in terms of calorific value on a gallon of diesel fue l in a cubic meter of gas. In other words, a diesel engine produces more power w ith less fuel than a gas engine.Results may vary but typically is between 12-75 % of fuel economy using diesel fuel. In addition, by design, diesel engines cons ume less fuel in "empty" about a 1 / 3 part vs gas. Initial Cost: Advantage Gas diesel engines they are designed and built a very robust (heavier and more robus t) eg cylindrical walls thicker, more robust block etc., and this usually means an increase in cost. Durability: Advantage diesel The diesel engine should be mu ch more robustly built to withstand / support the cylindrical compression ratios , temperature, etc.. Short Term Maintenance (Advantage) Gas Oil Changes in diese l engines are more expensive due to the capacity of the sump and filter life siz e (bigger). In addition, fuel filters and water separators must be changed more frequently. There are also aware that diesel engines do not require "tune up" as required by gas engines. One need only quote the price of an injection pump to realize the costs they are. Again, preventive maintenance plays a very important ! Long Term Maintenance (Advantage) Diesel Diesel engines typically they are des igned to work much longer hours and under adverse conditions, before requiring a n overhaul. We must also keep in mind that any negligence on the level of preven tive maintenance on a diesel engine will be in a much higher cost in terms of co rrective repair vs a gas engine. Note: The diesel engine tends to be more "Bullo us" that the gas engine, especially operating in a vacuum. Power in terms of dis placement "cc" Advantage: Difficult to quantify ..... Example, usually the large r or heavier the load factor (at low rpm), the diesel engine tends to be higher. Gas engines usually have more power in "peak" but this requires operation at hi gh engine speeds (rpm) and they are designed to operate in this way for long per iods. Diesel engines do not require work at higher revs to produce its maximum p ower "peak" and therefore if they are designed to GROUP # 1 INTERNAL COMBUSTION ENGINES operate during periods of time resulting in a higher life. Inertia in terms of a ssimilating "blocks" load: Advantage Diesel This is a very important point. Gene rator sets powered by a gas engine will not have enough mass / stability in view of its very light physical construction (manufacturing), and therefore can not assimilate "block load" treated as diesel engines. The latter causes serious pro blems of stability / instability on doing a "block" engine load. The proof is th at if you submit two sets of similar capacity (kVA) to a load block, notice that the gas engine tends to take more than the diesel engine in the process of assi milation of charge. In short, the diesel engine is ideal for this application du e to very robust diseòo and construction of it. Cold Temperature: Advantage Gas When the temperature drops (especially sub-zero) some delay in starting diesel e ngines. Equipping a diesel engine with a block heater (block heater) helps allev iate this problem. However, depending on where you placed this engine can be a b it difficult to find a power source to maintain the heater energized.
Gas Diesel engines are so called because they work like heavy oil diesel, or com pressed air only, fuel injected near TDC, at the end of the compression stroke, and depends solely on compressed air temperature to ignite the auxiliary fuel an d thus produce the ignition of gaseous fuel. These engines were the first high-c ompression gas-fired, but have been displaced by later types (mixed and spark) t hat are simpler and cheaper. One of the main models of diesel gas market is a tw
o-stroke engine Nordberg, the composition and general characteristics, such as c ompression pressure are equal to those of heavy oil Nordberg engine two times. I ts individual elements are: a gas compressor three-stage gas pressure rises to t he injection pump for each cylinder that drives the auxiliary fuel,injection va lves that admit both gas and heavy oil in each cylinder and a hydraulic mechanis m that opens the injection valves at the right time and varies the separation of these under the control of the regulator should be defined as the amount of gas needed to drag the load. GROUP # 1 INTERNAL COMBUSTION ENGINES The gas compressor is automatically controlled to supply gas to approximately 77 lb/in2. This gas reaches the injection valve mounted in the cylinder head from the storage bottle, after passing through a chiller and compressor. For each cyl inder there is an auxiliary fuel pump that delivers a small fixed amount of heav y oil to each of the injection valves. When a fuel valve opens, fuel is opened, the auxiliary fuel is blown by compressed gas cylinder, which is pre-compressed air to about 35 kp / cm2 and 540 ° C. This causes the ignition temperature and g as combustion also stabilizes it. A pump drive, led by the camshaft is connected through a pipe with an actuator mounted on the cylinder head, which synchronize s the opening of the injection valve and also controls the separation of the val ve. The controller varies the amount of hydraulic fluid that comes in every race drive pump, regulating the separation of the injection valve and the amount of gas injected. The amount of auxiliary fuel necessary to ignite and stabilize the combustion mixture is about 5% of the total full load of fuel, power calorífico .m measure in the performance of these fuel gas diesel engines in terms of calor ific gas and auxiliary fuel consumed per unit of useful power is approximately e qual to that which is working with heavy oil. However, the price is higher than the engine of a diesel power, given the existence of gas compressor, the hydraul ic operating mechanism and the additional liquid fuel pumps, hence the adaptatio n of a conventional diesel gas operation only is interesting for large engines. Fuel switching to switch from gas to consume consume heavy oil requires several hours. GASEOUS FUELS Both dual-fuel engines as the ignition work profitably with many types of gaseou s fuels and, in general, these fuels can be grouped into three broad classes: na tural gas Artificial Gases GROUP # 1 INTERNAL COMBUSTION ENGINES Gas Recovery These three classes differ not only their properties but what is important in its commercial availability. NATURAL GAS Natural gas is a more ideal fuel. Can be found in commercial quantities in many countries and distributes dare extensive pipeline network. It is not known natur al gas, but is often found associated with oil. Natural gas is odorless and colo r has a variable composition, depending on their origin, but methane is always m ore important as a component with 75% and 90%. The gas from a certain area usual ly contains sulfur as hydrogen sulfide, a highly corrosive compound, of a gas of this type is said to be a sulfur gas and also a working gas. GAS RECOVERY The gases are produced as byproduct during the manufacture of other substances a re called recovery gases such as well-known bottled fuel, butane and propane are easily liquefied at low pressure. They are also by-products are relatively chea p.
GAS FUEL SUPPLY The system of gas fuel is an installation that brings the gas supply to the need s and specifications of the gas engine. It is vital for the proper functioning o f the motor, which removes fluid and liquid, said supply pressure and remove sol id impurities that can drag the gas. This system takes the gas supplied by the d istribution network, separate compounds that come in liquid, regulated line pres sure to supply adequate engine governor GROUP # 1 INTERNAL COMBUSTION ENGINES It consists of a gas-liquid separator, a gas regulator and gas filter. The liqui d separator consists simply of a cylindrical plate inside where the inlet gas sh ocks, making coalesce liquid droplets carried by the gas and deposited on the in side, this action is favored by increasing the residence time of fluid and inclu ding changes in the direction of flow.Liquid separation is performed by expansi on and change of direction of flow in a container, decreasing the fluid kinetic energy when it collides with plates on their way, leaving the gas under the acti on of gravity as long as possible. This tortuous path and the residence time, it makes drops of liquid remain in the plates and opt for the action of gravity. T he separated liquid drain out through the bottom and can be manually or automati cally. The gas regulator has a membrane exposed on one side to a reference press ure (usually atmospheric pressure) and the action of a spring whose tension can be adjusted from outside by turning a screw cap and the other at the upstream pr essure through a hole. The gas pressure which is to regulate, enters through an orifice, according to the volume will provide and on which acts a shutter lever connected by a membrane. The operation of pressure regulator can be summarized as follows: if the upstrea m gas pressure regulator is increased, it is transmitted through a hole in the m embrane, pushing it up, with this action and through its lever system, the shutt er closes off the gas, which reduces the gas pressure, the spring pressure on th e membrane, it reacts by pushing down restoring balance and reopening the hole, with these actions will be able to maintain the gas pressure GROUP # 1 INTERNAL COMBUSTION ENGINES constant. The regulator using a mechanical membrane, and obturator antagonistic spring, maintains, raises or lowers the inlet pressure, conditioning is required by the carburetor of the engine. If the supply pressure is too high, you could use two pressure regulators of different ranks, connected in series, depending o n the application, before entering the carburetor. The system works well if the gas at the end of it, no liquid carryover and has the required pressure for the next step. To place under this system, I must ensure that the gas intake valve i s open the same, the liquid separator that is well drained and the gas regulator is adjusted to the required outlet pressure. If the system malfunctions we can see at the exit of a wet gas separator with high carryover of liquid or to take the pressure regulator output value is outside the range specified for it. To re move the liquid into the system: it must serve the same, draining all the fluids accumulated in the bottom of the separator. Regulation of gas pressure: the reg ulators can be adjusted to the desired pressure by placing a pressure gauge at t he outlet for a continuous reading, while pressure is regulated by adjusting the spring tension acting on the membrane. A common fault in the pressure regulator s is the rupture of the membrane. Safety precautions must be extreme because the system contains a fuel, so for any job in any of its components must be isolate d from the power supply of gas, vent gas pressure inside and drain fluids Joined also by any cause should be made hot work anywhere in this circuit. Regarding t he environment, we will be careful to collect all liquid drains and vents to tre
at than other circuits is recirculated gas treatment. Gaseous Fuel System (GFS) The Gaseous Fuel System (GFS) enables operators of diesel engines to reduce thei r operating costs and reduce emissions by substituting diesel fuel GROUP # 1 INTERNAL COMBUSTION ENGINES gas. The GFS system is comprised of proprietary technologies that allow the gas engine operation using percentages between 50% -70% of the total fuel required. Converted to gas engines have a behavior similar to diesel engines in terms of p ower, performance and efficiency. A key feature of the GFS system is its ability to change the fuel type without interrupting the operation of the vehicle. The conversion to gas does not require any internal modification to the engine, and can usually be done in a matter of hours. The GFS system is compatible with CNG and LNG storage. Applications: Urban and Municipal Buses, trucks, garbage trucks , dump trucks, locomotives, cranes, Construction Equipment, Mining Equipment, Tu gs. Advantages: Reduction in operating costs. If required, the vehicle can o perate 100% diesel. Reduced cost vs. gas combustion engines. Compatible with CNG and LNG storage. All high pressure components approved by CSA and UL list ed. Natural gas is supplied to the engine at atmospheric pressure. Reducing the risk of over supply of fuel. The concentration of gas in the engine combus tion air is less than 3%. The mixture is not explosive or flammable until they are compressed into the combustion chamber. Systems CNG / LNG has an excellen t safety record. The savings is based on the price differential between CNG / LNG and diesel. Differential high result in quick return. Application of hig h consumption result in greater savings. Installation Requirements: 8-10 man-h ours. No special tools required. It may require some mounting brackets. GROUP # 1 INTERNAL COMBUSTION ENGINES The implementation can be done on the road or dynamometer. Dimensions: Model S eries I Series II Series III Series IV Series Kilowatt (kW) Up to 150 300 350-60 0 350-1100 1200-3000 Power (HP) Up to 200 Up to 400 450-800 850-1400 1600-4000 GFS KIT Train of Diesel Fuel Gas Control Air-Gas Mixer Electroni c Control Wiring Harness CNG Level Display Optional Status Indicator System Inst allation Manual GROUP # 1 INTERNAL COMBUSTION ENGINES Performance: GROUP # 1 INTERNAL COMBUSTION ENGINES DIESEL FUEL SUPPLIES GROUP # 1 INTERNAL COMBUSTION ENGINES Generators powered by diesel engine are generally designed to operate with ASTM D975 diesel fuel number 2. Perhaps another type of fuel to function during a sho rt-term quality and physical characteristics in Table 1.
Diesel generators consume about 0.07 gal / hr (0.26 L / hr) of fuel per kW of to tal load range based on its range of emergency. For example an emergency generat or will consume 70 KW 100 gal / hr of fuel, there are considerable differences i n the capabilities of the engines from the manufacturers. In mechanical pumps th ere are many limitations on most engines, many facilities that require remote ma in tanks also require intermediate tanks. GAS FUEL SUPPLY Gas generators (also called ignition generators) can use natural gas or LP gas o r both. The dual systems with natural gas as primary fuel and LP gas as a backup can be used in seismic risk areas and where there is concern that a natural eve nt can disrupt the functioning of the public gas grid. Regardless of the fuel us ed, the main factors in the installation and successful operation of a gas syste m are GROUP # 1 INTERNAL COMBUSTION ENGINES The gas supplied to the generator must be of acceptable quality. The gas supply mu st have enough pressure. The generator must supply gas in sufficient volume to support its operation, to LP suction systems, the tank size and temperature als o affect this requirement. QUALITY OF FUEL GAS Gaseous fuels are a mixture of different hydrocarbons such as methane, ethane, p ropane and butane, other gaseous elements like oxygen and nitrogen, vaporized wa ter and various contaminants, some of which are potentially harmful to the engin e over time. The quality of fuel is based on the amount of energy per unit volum e and the amount of energy per unit volume and the amount of pollutants in. ENERGY CONTENT One of the most important features in the gas generator is used in a heat value. The fuel value describes how much energy is stored in a specific volume of fuel . The gas has a lower heating value (LHV) and a heat value (HHV). The value of h eat available to do the work in an engine after the water has vaporized fuel. If the low heat value of fuel is too low, even if a sufficient volume of fuel to t he engine, the engine can not maintain total power output because there is insuf ficient energy in the engine into mechanical energy convertidla if the LHV is be low 905 BTU/ft3 the engine could not produce power in a standard ambient tempera ture conditions. Each engine may have slightly deferential performance character istics based on the type of fuel supplied, due to compression deference, and if the engine is normally aspirated or turbo charged. NATURAL GAS LINE GROUP # 1 INTERNAL COMBUSTION ENGINES The most common fuel for generators is called "natural gas line." In the United StatesDry natural gas line has specific qualities based on federal requirements in other countries the natural gas line may vary in content, and its characteri stics should be checked before use with a generator. The U.S. natural gas is a c ompound pro mescal 98% methane and 2% of hydrocarbons such as butane and propane . GAS FIELD The composition of natural gas field varies considerably by region and continent . Careful analysis is required before using natural gas field may have heavier h
ydrocarbons such as pentane, hexane and heptane derratear which require motor ou tput. They may also have components such as sulfur. PROPANE (LPG) Propane is available in two grades on commercial or special use. The commercial propane is used where high volatility is required. Not all spark ignition engine s operate acceptably with the fuel due to its volatility. The special use propan e also known as HD, is a mixture of 95% propane and other gases such as butane t hat allow better performance through reduced volatility. The propane fuel specia l use conforms to the ASTM 1835 for special use propane. CONTAMINANTS The most damaging pollutants in gaseous fuels are sulfur and water vapor. Water vapor is harmful because it can cause burning uncontrolled pre-ignition or other effects that can damage the engine vapor or liquid droplets must be eliminated from the fuel before entering this with one of "dry filter" that Note the fuel s ystem pressure regulator before the primary fuel. Sulfur causes corrosion and se rious damage to the engine in very short periods of time, the effects of the dam age of sulfur can be counteracted by the use of certain high-ash lubricants. GROUP # 1 INTERNAL COMBUSTION ENGINES CONCLUSIONS
In discussing the benefits of gas fuel gases are obtained as a byproduct durin g the manufacture of other substances are called recovery gases among which are butane and propane which are easily liquefied at low pressure. They are also byproducts are relatively cheap. In discussing the benefits we also find the fol lowing features. Easy to handle and transport via pipeline No ashes or forei gn matter present The combustion control is much easier, allowing us to mainta in the temperature of combustion even with variable demands They come or tend to come from low-quality solid fuels therefore allows us to give better use suchfuels GROUP # 1 INTERNAL COMBUSTION ENGINES BIBLIOGRAPHY
Diesel and gas engines high compression Author Edgar J. Kates, W.E. Contributor Luck W.E. Luck Published by Academic Press, 1982. Liquid Cooled Generators, Application Manual. Commins 2004 Power Generation. GFS Corporation 1363 Shotgun Road Weston, FL 33 326-corp.net www.gfs http://www.marn.gob.gt/info/extrafiles/Documentos% 20T ecnicos/6-TratadosAmbientalesGuatemala.zip http://www.marn.gob.gt/info/extrafiles/Documentos% 20T ecnicos/1-CalidadAmbientalGuatemala.zip http://cabierta.uchile.cl/revista/13/articulos/13_3/index.html http://es.wik ipedia.org/wiki/Motor_alternativo http://www.directindustry.es/fabricante-indu strial / motor-gas73658.html http://www.cat.com/cda/layout?m=37533&x=9 82200412594.pdf
http://www.hsb.com/cmsfiles/449-SP
GROUP # 1 INTERNAL COMBUSTION ENGINES RECOMMENDATIONS Whether continuous or intermittent, diesel engines require maintenance if they are to perform as expected. During the life of an engine, fuel represents about 75% of total operating costs. Moreover, if fuel quality is not maintained, can cause premature engine failure or decreased performance. Often overlooked t he desirability and status of diesel fuel as a matter of maintenance. Know You r Fuel Quality Never add gasoline or diesel fuel alcohol any reason. Doing so will damage the fuel injection system. The diesel fuel is more prone to oxidation than the gasoline. Never stay in storage for more than 12 months. If the coolant level drops to a point where the air is drawn into the cooling jackets, cooling capaci ty is reduced, resulting in serious mechanical damage, including cavitation corr osion. Always check the coolant level. ANNEXES GROUP # 1 INTERNAL COMBUSTION ENGINES Gas engine Waukesha Engine 1160 kW / 4830 kW Gas engine (Caterpillar) Supercharged gas engine (Perkins) Diesel fuel specifications GROUP # 1 INTERNAL COMBUSTION ENGINES GROUP # 1 INTERNAL COMBUSTION ENGINES GROUP # 1 INTERNAL COMBUSTION ENGINES Minimum size of hose and tube GROUP # 1 INTERNAL COMBUSTION ENGINES Allowable maximum rates for Motor Fuels Allowable maximum rates Constituents Before Derratear Gas Engines Turbochargers Typical Gaseous Fuel System
GROUP # 1 INTERNAL COMBUSTION ENGINES Minimum size of LPG tank (50% full) required to maintain the specified range 5 P SIG suction and expected minimum winter temperature GROUP # 1 INTERNAL COMBUSTION ENGINES GLOSSARY Gaseous Fuel: Gaseous fuels are called hydrocarbons to natural and manufactured exclusively for use as fuel, and those obtained as a byproduct in certain indust rial processes that can be harnessed as fuels. Specific Heat: Specific heat, or more formally the specific heat capacity of a s ubstance is a quantity GROUP # 1 INTERNAL COMBUSTION ENGINES physics that indicates the ability of a material to store energy as heat inside. CNG: Compressed natural gas is a fuel for vehicular use that, because economic a nd environmentally clean, is essentially natural gas stored at high pressures, t ypically between 200 and 250 bar, according to the regulations of each country. LNG: Liquefied natural gas is natural gas that has been processed to be transpor ted in liquid form. It is the best alternative to monetize reserves in remote pl aces, where it is not economical to carry the gas to market directly either by p ipeline or power generation. Diesel: It is a liquid whitish or greenish and density of 850 kg per cubic meter , which consists mainly of paraffins and used mainly as fuel for diesel engines and heating. Natural Gas: Natural gas is a mixture of gases commonly found in fossil deposits , Gas Recovery: obtained as a byproduct during the manufacture of other substances are known as gas recovery well known such as bottled fuel, butane and propane Liquefied Petroleum Gas: liquefied petroleum gas is a mixture of condensable gas es present in the natural gas or dissolved in oil. LPG component, but environmen tal temperature and pressure are gases, they are easy to condense, hence its nam e. In practice, one can say that LPG is a mixture of propane and butane. Flammability Limits: air and gas rates that have a mixture of both so you can st art and spread the combustion of the mixture. GROUP # 1 INTERNAL COMBUSTION ENGINES Fuel system gas: is a facility that brings the gas supply to the needs and speci fications of the gas engine. Ignition temperature: the minimum temperature that can be initiated and propagat ed at a point of combustion air mixture gas.
Burning velocity: The speed of propagation of a stable flame GROUP # 1