Design of Automated Biomass Gasifier

Design of Automated Biomass GasifierABSTRACTBiomass botchifiers have found a promising jell in renewable energy resource field. dismantle then, these throttle valveifiers be facing lots of practical difficulties on operational potence due to shortage of man military unit. So small plateful biomass gasifier is counterbalance and march on the give the axe looking scheme and switching functions (On/Off Operations) be also changed by means of mechanization. Bucket conveyors are employ to feed the supply from the reservoir to the pre- storage sleeping accommodation. The burn down provide be fed in equal intervals of time to primary(prenominal)tain constant take of fuel in the reactor. The aim of the fuel in pre-storage put up can be checked by means of level sensors. Ignition of the gasifier is also change apply a special fervor set up. either these automations are achieved by utilise microcontrollers, sensors and limit switches.Keywords Biomass gasifier, auto mation, conveyor, microcontrollers.I. INTRODUCTIONBiomass gasifier has evolved in different aspects for more than triplet decades. M each improvements were made in biomass gasifiers. The rectifications of the flaws found in the gasifiers were sorted pop researched and good results were obtained. Highly efficient biomass gasifiers of different emblem are in existence at present.Even then in that respect are some(prenominal) chores to overcome in order to make the biomass gasifier further more efficient.The primary(prenominal) challenging factors to make the biomass gasifiers highly efficient both equal flip performance wise are as follows, (i)Gasification is quite complex and nociceptive edge. (ii)Due to the day-and-night working of the frame it requires the repeated refueling. (iii)The removal of residues such as ash and other residues is taking more time.(iv)The formation of producer gas is very easy, but getting the proper state is very difficult.(v)Man power is ext remityed for fueling, igniting and monitoring. Thus resulting in expenditure for safety aspects of human resources, which makes it cost inefficient the system. (vi)Toxicity of producer gas is also a major problem which affects the humans.Amongst all the problems faced, the major problems falls in a category of need for automation. The automation can be done in any type of biomass gasifier. This paper focuses on automating downdraft gasifier in particular. The concept of automation of the biomass gasifier bestir oneselfed from the year of 1980 by Bil finger industrial automation services. Various up-gradations and the changes are brought into example after the middle of 1990s the automation of gasifier is still creation debated for further improvements.A. Automation of the Gasifier Using MicrocontrollerEnergy systems that rely upon biomass fuel are much very complex due to the need for the systems to integrate fuel handling, electrocution control, and ash removal. Automation of b iomass gasifier is capable of offering a wide picture of solutions to suit these needs. These are achieved by utilizing a variety of PLC and SCADA systems at present 1.Even though PLC SCADA finds a promising place in automation of biomass gasifier 1 there were few disadvantages like highly expensive system for being installed in small outperform and medium scale gasification unit technical workers with deep knowledge about these controlling system are needed. thusly this paper mainly focuses on automation of then gasifier from small scale to large scale unit. This can be achieved by automate the gasifiers using microcontroller.A Microcontroller is a digital computer on a virtuoso chip but usually runs for performing a dedicated task. It has CPU, memory, timers, check Serial I/O and peripherals, counters and clock circuit. The primary operation of a microcontroller is performed by using a fixed program that is stored in the ROM. Because of absence seizure of CPU, RAM, ROM, Per ipherals all embedded on a single chip in microprocessor, microcontroller has a greater advantage over it. This in turn reduces the coat of the application and cost. It consumes low power because it operates at low frequencies and so it is run into for durable application.II. DESIGN OF AUTOMATED GASIFIERDowndraft gasifier, the upper cylindrical part of gasifier acts as a collection device for wood chips or other biomass fuel 4. The downdraft gasifier is shown in Fig. 1. Below this cylindrical part of gasifier, there is a radially directed air snot that permits air to be drawn in to the raw material, so they become gasified. Before the pyrolyzing of biomass it contacts with atmospheric air, char and deem a char. It rapidly consumes limited air supply for getting richer flame in the pyrolysis zone. At the final stage of pyrolysis zone, the gases consist most(prenominal)ly of Co, H2o, Co2 and CH4 5. The throat ensures that the gaseous products pass through the hottest zone where most of the tar cracked into gaseous hydrocarbon. Thus produces relatively clean gas.A. Components of gasifierAll the components of downdraft gasifier are designed in soildworks software. Main components of automated downdraft gasifier and their design are described below.1. HopperThe purpose of a groundball is to store the biomass for continuous feed to reaction chamber. It is mounted above the reactor of gasifier. The fuel storage hopper is made up of 4mm thick mild steel. The diameter and tallness of fuel hopper is chosen to be 220mm and 550mm on an individual basis 2. Round do hopper has been chosen to prevent the problem of biomass being stuck.2. Gasification ZoneThis is the main component of gasifier. The main reaction of gasification like oxidation, reduction and distillation takes place in this zone. It is in the shape of vertical convergent and divergent nozzle (from give-up the ghost to get across direction) and made by 3mm thick mild steel. fastness diameter of div ergent section is 100mm and the lower diameter is of 220mm with 100mm superlative respectively 2.3. Outer CylinderA cylinder is made to cover the total gasification assembly. The height and diameter of cylinder are 220mm and 250mm respectively 2.B. Components of automated gasifierThe components of automated gasifier and their design are described below.1. Pre-storage chamberA pre storage chamber is made to store the fuel after the fuel pirogue and onward the fire chamber. The height and diameter of cylinder are 200mm and 300mm respectively. 500mm length room access frame is rigid on the top of cylinder, same500mm length admission frame placed on the bottom of the cylinder. And 250mm outer diameter and 220mm intimate diameter flange. 8 holes of 10mm diameter are drilled in the plates to marry the hopper and pre-storage chamber with the help of nut and bolts.2. Pre Storage Door with guide on screwA pre-storage door with lead screw is placed deep down of the door frame. It is used to avoid the atmospheric air to inside the combustion zone. The length, breadth and thickness of door are 300mm, 210mm and 2mm respectively. And the Diameter, Length, Pitch and Thread height of lead screw are 19mm, 320mm, 6mm and 3mm respectively. The Diameter, Length, Pitch and Thread height of encase nut are inner diameter- 20mm, outer diameter- 40mm, 35mm, 6mm and 3mm respectively. The door is placed on the top of cylinder, same door frame placed on the bottom of the cylinder.3. send away hit with conveyor systemA fuel pirogue with conveyor is made to store the fuel in the fuel bunker and convey the fuel from fuel bunker to pre-storage chamber (Bucket conveyors were used in the system) 3. The height, length and width of fuel bunker are 400mm, 450mm and 450mm respectively. And the conveyor is placed inside of the fuel bunker another end is placed on the top of the pre-storage chamber.C. Assembling of automated gasifierIn order to assemble the gasifier components, sta rt of all water tank is placed on the stand and the gasifier is placed inside the tank. Now the pre-storage chamber is placed to top of the hopper and amount with the help of nut and bolts. And the fuel bunker with conveyor is placed on the stand one end of the conveyor is fixed inside of the fuel bunker and another side of the conveyor is fixed on the top of the pre-storage tank with help of bolts and nuts. The schematic of automated gasifier unit is shown in fig. 1.Fig.1. schematic drawing of automated gasifier unitIII. COMPONENTS OF CONTROL SYSTEMA. Microcontroller kitMicrocontroller kit is used to control the sequence of operation in this system, like door consecrate sozzled, conveyor system on/off, igniter on/off, blower on/off. These operations are control by according to the sequence of operation.B. SensorsIR proximity sensor is act as a level sensor. The level of the fuel in pre-storage chamber can be checked by means of level sensors. It can able to sense the nearby obj ect lenss without any disturbance of the sensed object. It does not have any mechanical move and also lack of direct contact between sensed object and sensor. So it has high durability and high reliability.C. MotorsMotor is used to arrive the conveyor system and door open close operations. These are controlled by microcontroller kit.D. Limit switchesLimit switch is a device which converts mechanical apparent motion in to electric signal. It is operated by physical contact of the object. In this system limit switches are used to control the door open close system.Fig.2. Automated small scale gasifier unitIV. SEQUENCE OF OPERATION strike chart for sequence of operationStarting process Continuous processIf the fuel level comes down in the hopperB. Flow chart descriptionStarting process tonicity 1 set the aliment time interval in the microcontroller kit (using adjustable time regulator). trample 2 press the press button to start the process.Step 3 door 1will be open (using motor l imit switch).Step 4 conveyor on fuel is taken from fuel bunker to pre-storage chamber.Step 5 if the fuel attains the maximum level in pre-storage chamber, the conveyor system will be cut off (using sensor to check the level of fuel in pre-storage chamber).Step 6 after(prenominal) these door 1will be close.Step 7 And then door 2 open. The fuel comes from pre-storage chamber to hopper.Step 8 After 25 sec door 2 will be close.Step 9 repeat from step 1 to step 6 another one time for filling the hopper (this repeating process is adjustable in the program. it depends upon the fuel).Step 10 After this process air blower will be on (for creating compress in the gasification zone).Step 11 After 1min igniter will be on (using impulsive igniter).Continuous processThe continuous process will happen for every equal interval. The time interval is adjustable (before start the whole process to set the time interval depends up on the fuel characteristics).Step 1 door 1 open.Step 2 conveyor on fue l is taken from fuel banker to pre-storage chamber.Step 3 if the fuel will be attain maximum level in pre storage. The conveyor system will be cut off.Step 4 door 1 close.Step 5 door 2 open. The fuel comes to hopper.Step 6 After 25 sec door 2 will be closeV. CONCLUSIONThus the small scale biomass gasifier was designed and fabricated with automatic controls. This gasifier is initiated with the manual feeding of biomass in the Fuel bunker, set the equal time interval for feeding from fuel bunker to pre-storage chamber and press the push button to start process there after the entire process like fuel feeding system, ignition system, switching functions (On/Off Operations), equal interval of feeding was automated using microcontroller, sensors, limit switches and motors. In future to develop the gasifier in fully automatic mode, to controlling and monitoring the gasifier parameters like temperature, pressure, air flow rate and gas flow rate etc. And also implement this automation in la rge scale gasfiers.