Alternative Fuels In Aluminium Casting Industry | Pengecoran Aluminium31 May 2014
Initial studies have been conducted to evaluate the storage stability . Rice straw powder settles at the bottom of the fuel due to its density is greater. For prolonged storage , a mixture of rice straw particles and kerosene needs to be stabilized . Another characteristic is the sediment particles will form if the mixture is not stirred periodically . The phenomenon of subsidence and sedimentation have been prevented with better by adding aditive .
It has been found that rice straw particles can be prevented so as not to emulsify the fuel settles CBM with polar liquids such as water and / or short- chain alcohols . In the economic potential and , specifically studied emulsion material to produce stable CBM fuel , using 3 types of emulsifiers are water , ethanol and 1 % CMC ( Carboxy Methyl Celluloce } . Rice straw particle size that is used for fuel CBM filtered through 75 um ( 100 % passes through 200 mesh ) . (pengecoran aluminium )
Three types of formulations rice - straw mixture of kerosene has been developed , which is a mixture of rice straw - kerosene - water , ground rice straw - oil - water - ethanol , oil and rice straw - soil - water - CMC 1 % . Rice - straw mixture of kerosene - water prepared with 15 wt % rice straw , and water with 4 different concentrations , namely ; 15 , 25 , 35 , 40 wt % . Rice - straw mixture of kerosene - water - ethanol was prepared by using a 20 wt % rice straw , 15 % water and ethanol with 4 different concentrations , namely 10 , 20 , 30 , 40 wt % . Rice - straw mixture of kerosene - water - CMC was prepared by using a 20 wt % rice straw , 15 wt % water and 1 % CMC with 4 different concentrations , namely ; 10 , 20 , 30 , 40wt % .
To test stability , almost all of the mud is prepared in a 250 ml beaker . The average amount of sludge for each test is 80 grams or 100 ml . Total sludge is sufficient to detect differences in the nature of deposition of silt . The mass fraction of rice straw in a variety of mud from 15 to 20 % . This number is believed to be sufficient to evaluate the stability of the mud . Time stability of fuel sludge visually inspected each day for each sample . It was found that all formulations of slurry fuel for a particular mixture is stable for a long period ie within 12 days without any precipitation looks .
Further investigation is the rheological properties of CBM fuel . The main part of this phase of the investigation was to measure the apparent viscosity of the fuel CBM stable . Viscosity was measured using a Thermo Haake Viscotester VT5L ( type of rotational viscometer ) . VT5 Viscotester Model L has 19 rounds ( from 0.3 min to 200 min ) . The distance between the cylinder and the outer cylinder is 2.29 mm . For each pair of shear stress and strain rate , the viscosity of the fuel CBM is plotted as a function of strain rate .
Of real - viscosity curve strain rate ( rheogram ) for all formulations showed a tendency CBM fuel power-law model . Rheogram plotted on a log - log scale to fit power-law model . The slope of the linear line stating the value of n - 1 and the intersection declared value k . Data to accurately match the power-law model of Ostwald de Waele from . From the values of n and k , it was found that all formulations of fuel CBM can be characterized as non-Newtonian fluids with rheological shear thinning ( pseudoplastic ) . The present invention has advantages and is very helpful especially when fuel is pumped CBM , injected or sprayed . The reason is that the CBM fuel viscosity will decrease when the rate rose rengangan as if fuel is flowing through the atomiser .
The next stage of the research focused on the cold test and hot test fuel CBM . Testing is once again testing the performance or atomiser nozzles are designed . Atomiser nozzles used are pneumatic type air- blast atomizer using compressed air as a fluid atomising . Working pressure is set constant that is used CBM pressure of 0.5 kg / cm ( gauge ) and the atomization air pressure of 1 kg/cm2 ( gauge ) . It was found that all the formulations can be atomized CBM well . The stability of the bursts looks very stable on the formulation of CBM 20 wt % straw - 45 wt % kerosene - 20 wt % ethanol - 15 wt % water . Physically CBM with these formulations showed the most homogeneous , where the liquid fraction and a solid fraction fused and no significant separation . Long bursts occurred ranged from 125 to 135 cm .
Testing combustion ( heat test ) was performed to determine the combustion characteristics kemampubakaran and CBM is long fire and flame temperature . From the results of hot trials found that all formulations CBM after atomized easy to be lit . This suggests that the use of water - blast atomizer nozzle mixing type outside (external mixing ) is quite successful in all formulations mengatomisasi CBM CBM so flammable. As in the atomization process , burning straw CBM 20 wt % - 45 wt % kerosene - 20 wt % ethanol - 15 wt % water flame that happens very stable , it is in accordance with the results of the cold test . The length of the fire that occurred closer to the long bursts atomization results . This shows that the result of atomization is quite good , so that the whole can be formed droplet burning . Flame temperature of the whole formulation CBM shows the value of the temperature above 1000 C and is believed to be enough to melt the aluminum where the melting point of aluminum is 700 C.
The last stage of the two -year study is testing the aluminum smelting process , either with or with CBM biobriket . From this stage it was found that of the aluminum smelting process using kerosene fuel ( kerosene ) , using the same nozzles , nozzle spacing kowi to the same , and fuel pressure the same work , spending the amount of oil 3.3 kg / kg of aluminum , lower than 20 % CBM Straw - 45 % kerosene - 20 % ethanol - 15 % water ( 8.6 kg / kg of aluminum ) , 15 % Straw - 60 % kerosene - 25 % water ( 9.8 kg / kg of aluminum ) and 20 % -55 % kerosene Straw - 10 % CMC 1 % - 15 % water ( 10.2 kg / kg of aluminum ) . It caused 100 % kerosene has a heating value content of greater than all formulations CBM of straw . The length of a large fire also caused loss of heat from the furnace to the larger environment. In the process of smelting aluminum with fuel biobriket found that to melt 1 kg of aluminum required biobriket of 6.25 kg or 7 kg teak wood biobriket of biobriket glugu or 8 kg of rice straw .
Finally , the results of this study can be recommended for the type of fire that CBM is long and large, the CBM potential applications developed for heating in a furnace large hallway , eg in boiler / steam kettle . CBM performance can still be improved by using a type of biomass that has a higher calorific value than hay .