Currently, various methods have been developed to overcome the problems caused by garbage. Pyrolysis is one methode of waste processing which is considered to be prospective enough to be developed. It's because some advantages such as high conversion ratio and high energy content and potency as an alternative fuel in the future. Therefore, in this paper characteristics of pyrolysis will be studied. The waste materials used are catalyst and plastic waste. The resultant products of the pyrolysis process analyzed by Gas Chromatography / Mass Spectroscopy (GC / MS), while the thermal decomposition analysis was performed using Thermo Gravimetric Analysis (TGA). The results of pyrolysis process in isothermal conditions of a single component and a mixture of plastic waste and natural catalyst show that the final temperature of pyrolysis and the rate of heating affects to the distribution of pyrolysis products for all samples. As pyrolytic temperatures increase, liquid and gas products increase, while solid products tend to decrease. In the temperature range of 300°C, 400°C, 500°C, 600 o C pyrolysis temperature with a heating rate of 100°C / min is the ideal temperature for obtaining the pyrolysis product of the liquid fraction and and the maximum gas fraction for all waste types studied.
Nozzle shape greatly influence turbulence between the fuel, air and formation of flow recirculation zone to produce a homogeneous mixing and get a near-perfect combustion. The PENDAHULUANProses pembakaran merupakan proses yang sangat penting dalam memanfaatkan energi kimiawi bahan bakar yang digunakan untuk memenuhi kebutuhan energi manusia. Salah satu jenis pembakaran yang umum digunakan dalam bidang industri adalah pembakaran difusi. Pada pembakaran difusi bahan bakar yang dialirkan melalui saluran burner dibuat terpisah dari saluran udara, sehingga pencampuran bahan bakar dan udara tidak terjadi secara mekanik sebelum terjadinya proses pembakaran melainkan bercampur sendiri secara alami dengan proses difusi sesaat sebelum proses pembakaran. Salah satu keuntungan digunakannya pembakaran difusi pada bidang industri adalah dari sisi keamanan, yaitu tidak adanya bahaya flash back. Tetapi di sisi lain, pembakaran difusi memiliki kelemahan yaitu sulitnya mendapatkan komposisi campuran yang homogen antara bahan bakar dan udara. Oleh sebab itu, salah satu upaya untuk mengatasi permasalahan tersebut adalah dengan cara mendesain sistem pembakaran difusi yang optimal, sehingga didapatkan suatu desain burner yang efektif dan efisien.Salah satu faktor yang mempengaruhi karakteristik pembakaran api difusi adalah geometri burner. Geometri burner sangat berpengaruh dalam proses pencampuran antara bahan bakar dan udara, sehingga mempengaruhi karakteristik pembakaran. Pada proses pencampuran antara bahan bakar dan udara, kehadiran vorteks-vorteks akibat struktur geometri burner berperan penting sebagai pengaduk aliran. Dinamika vorteks hadir pada struktur aliran api non-premix yang bertujuan untuk menstabilkan proses pembakaran [1]. Daerah kestabilan api difusi dapat diperluas dengan pemasangan swirling vanes [2]. Kestabilan api pada umumnya menjelaskan batas operasional dari sistem pembakaran. Ada dua kondisi aliran kritis yang berhubungan dengan kestabilan api, yaitu lift off dan blow off. Oleh karena kondisi kritis batas kestabilan tersebut sangat tergantung pada kondisi geometris burnernya, maka pada penelitian ini digunakan nozzle dengan variasi lip thickness terpancung pada tipe burner concentric jet flow. Lip thickness burner berpengaruh terhadap kestabilan api non-premixed akibat perubahan zona resirkulasi aliran [3]. Aliran resirkulasi yang merupakan faktor penting dalam kestabilan api dengan jalan pengadukan bahan bakar baik di belakang halangan maupun untuk proses pencampurannya [4]. Zona resirkulasi adalah daerah dimana terjadi pemecahan laju aliran yang menimbulkan pusaran (vortex) dan aliran balik di sekitar ujung nozzle. Dengan penggunaan variasi lip thickness nozzle terpancung pada penelitian ini, diharapkan akan terjadi pemecahan laju aliran sehingga terbentuk zona resirkulasi yang akan menyempurnakan pembakaran. Hal ini diindikasikan dengan kemudahan terbentuknya lift off dan blow off sebagai indikator kestabilan api difusi.Pengaruh kecepatan bahan bakar pada concentric jet flow terhadap kondisi li...
Experimental studies of the Archimedes screw turbine are applied as a micro hydro power plant for low head focused on the fluid flow. Fluid flow on a screw turbine is not completely filled water flow there is still a free surface between the water fluid and atmospheric air. Except the screw geometry, the turbine screw free surface allows the flow phenomena that are important in the process of turbine screw power generation. The Archimedes screw turbine main driving force is the fluid-gravity weight, which is affected by the inflow depth, inflow velocity and the turbine shaft's slope. The dimensionless parameter Froude number (Fr) is connected to analyze the screw turbine efficiency. The purpose of this study is to figure out the fluid flow role when power generated by a three blades Archimedes screw turbine observed visualized, and also observed the turbine rotation and torque. The observed parameters are varied in inflow depth as the characteristic length (y) of Froude Number, inflow velocity (co), and the turbine shaft slope (α). The screw turbine model, were made under a laboratory scale and made from acrylic material. The geometric form is the three bladed screws which have seven screw respectively, the number of helix turns is 21, the angle of screw blade is 30°, radius ratio of 0.54 with a pitch distance of 2,4 Ro. The result from this study revealed a phenomenon of fluid flow between the screw blades a whirlpool wave occurs or vortex due to the linear momentum in a form of the hydrostatic force against the blade screw which occurs in two opposite directions and the effect of the turbine shaft angular momentum. The vortex would affect the screw turbine power generation process as most of the kinetic energy that goes into the screw turbine sucked into the vortex between the screw blades, but this phenomenon can be reduced by reducing the turbine shaft slope. The highest turbine efficiency of 89% occurred in the turbine shaft's slope of 25° and a flow rate of 0.5 m/s and a 1Ro characteristic length and a 0,12 Froude number.
The depletion of fossil fuel availability and increase of pollution due to the use of fossil fuels have forced the researcher to find a renewable-friendly energy source. One of the potential replacements is alcohol based fuel. This present study investigated experimentally the influence of ethanol addition on the engine performance, in terms of effective power, brake specific fuel consumption, and exhaust emissions of a gasoline spark ignition engine. The engine used in the research was a 4-stroke single cylinder, indirect injection system with engine capacity of 124.8cc, and compression ratio of 9.3:1. The experiments were conducted at eight different engine speeds ranging from 1500 rpm to 5000 rpm and 10 types of gasoline-ethanol mixtures (E10 to E100). The result showed that the effective power decreased with the increase of ethanol in the fuel blends for all variations of engine speed. Leaning effect of ethanol addition in the blend fuel caused the CO emissions to decrease greatly as well as the HC emissions. On average, gasoline engine fueled by pure ethanol reduced the CO emission level by more than 60 % in volume compared to the engine with gasoline fuel. On average, the maximum power of the engine with fuel blend was obtained at engine speed of around 2500 to 3000 rpm. For higher ethanol content on the fuel blend, the optimum shift to the lower engine speed. It can be concluded that engine operation with ethanol content on the fuel performed better in the lower engine speed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.