Design of Automated Biomass Gasifier

Design of Automated Biomass Gasifier ABSTRACT: Biomass gasifiers have found a promising place in renewable energy resource field. Even then, these gasifiers are facing lots of practical difficulties on operational effectiveness due to shortage of man power. So small scale biomass gasifier is fabricate and further the fuel feeding system and switching functions (On/Off Operations) are also changed by means of automation. Bucket conveyors are used to feed the fuel from the reservoir to the pre-storage chamber. The fuel will be fed in equal intervals of time to maintain constant level of fuel in the reactor. The level of the fuel in pre-storage chamber can be checked by means of level sensors. Ignition of the gasifier is also automated using a special ignition set up. All these automations are achieved by using microcontrollers, sensors and limit switches. Keywords: Biomass gasifier, automation, conveyor, microcontrollers. I. INTRODUCTION: Biomass gasifier has evolved in different aspects for more than three decades. Many improvements were made in biomass gasifiers. The rectifications of the flaws found in the gasifiers were sorted out; researched and good results were obtained. Highly efficient biomass gasifiers of different type are in existence at present. Even then there are many problems to overcome in order to make the biomass gasifier further more efficient. The main challenging factors to make the biomass gasifiers highly efficient both cost wise performance wise are as follows, (i)Gasification is quite complex and sensitive process. (ii)Due to the continuous working of the system 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 needed 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 started from the year of 1980 by â€Å"Bil finger industrial automation services†. Various up-gradations and the changes are brought into practice after the middle of 1990’s the automation of gasifier is still being debated for further improvements. A. Automation of the Gasifier Using Microcontroller Energy systems that rely upon biomass fuel are often very complex due to the need for the systems to integrate fuel handling, combustion control, and ash removal. Automation of biomass gasifier is capable of offering a wide range 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 scale and medium scale gasification unit skilled workers with deep knowledge about these controlling system are needed. Hence 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 single chip but usually runs for performing a dedicated task. It has CPU, memory, timers, Parallel 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 of CPU, RAM, ROM, Peripherals all embedded on a single chip in microprocessor, microcontroller has a greater advantage over it. This in turn reduces the size of the application and cost. It consumes low power because it operates at low frequencies and so it is fit for durable application. II. DESIGN OF AUTOMATED GASIFIER: Downdraft 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 nozzle 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 support a flame. It rapidly consumes limited air supply for getting richer flame in the pyrolysis zone. At the final stage of pyrolysis zone, the gases consist mostly of C ­o, 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 gasifier: All the components of downdraft gasifier are designed in soildworks software. Main components of automated downdraft gasifier and their design are described below. 1. Hopper: The purpose of a hopper 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 height of fuel hopper is chosen to be 220mm and 550mm respectively [2]. Round shaped hopper has been chosen to prevent the problem of biomass being stuck. 2. Gasification Zone: This 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 top to bottom direction) and made by 3mm thick mild steel. Upper diameter of divergent section is 100mm and the lower diameter is of 220mm with 100mm height respectively [2]. 3. Outer Cylinder: A cylinder is made to cover the whole gasification assembly. The height and diameter of cylinder are 220mm and 250mm respectively [2]. B. Components of automated gasifier: The components of automated gasifier and their design are described below. 1. Pre-storage chamber: A pre storage chamber is made to store the fuel after the fuel bunker and before the combustion chamber. The height and diameter of cylinder are 200mm and 300mm respectively. 500mm length door frame is placed on the top of cylinder, same 500mm length door frame placed on the bottom of the cylinder. And 250mm outer diameter and 220mm inner diameter flange. 8 holes of 10mm diameter are drilled in the plates to join the hopper and pre-storage chamber with the help of nut and bolts. 2. Pre – Storage Door with lead screw: A pre-storage door with lead screw is placed inside 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 box 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. Fuel bunker with conveyor system: A fuel bunker 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 gasifier: In order to assemble the gasifier components, first 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 join 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 of automated gasifier unit III. COMPONENTS OF CONTROL SYSTEM A. Microcontroller kit: Microcontroller kit is used to control the sequence of operation in this system, like door open close, conveyor system on/off, igniter on/off, blower on/off. These operations are control by according to the sequence of operation. B. Sensors: IR 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 objects without any disturbance of the sensed object. It does not have any mechanical parts and also lack of direct contact between sensed object and sensor. So it has high durability and high reliability. C. Motors: Motor is used to drive the conveyor system and door open close operations. These are controlled by microcontroller kit. D. Limit switches: Limit switch is a device which converts mechanical 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 unit IV. SEQUENCE OF OPERATION Flow chart for sequence of operation Starting process Continuous process If the fuel level comes down in the hopper B. Flow chart description: Starting process: Step 1: set the feeding time interval in the microcontroller kit (using adjustable time regulator). Step 2: press the press button to start the process. Step 3: door 1will be open (using motor limit 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 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 pressure in the gasification zone). Step 11: After 1min igniter will be on (using automatic igniter). Continuous process: The 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 fuel 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 close V. CONCLUSION Thus 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 large scale gasfiers.

Are Cell Phones Necessary in Teen’s Lives? Essay

I believe that cell phones are necessary in teen’s lives for the following three reasons. Firstly, they are a good social way to keep in contact with friends and family. Secondly, they are a fast and easy emergency resource. Thirdly, cell phones are an easy way to access the internet and they are entertainment to teens. Firstly, I believe that cell phones are a good social way to keep in contact with friends and family for the following three reasons. A lot of teen’s need to keep in touch with their family and friends so they can know whether or not they have anything after school. Having a cell phone makes it easy for teen’s to talk to their friends and family on any day at any time. Lastly, if there is a sudden change with any plans they have, having a cell phone makes it easy to keep in contact. Therefore, for those reasons I believe cell phones are necessary in teens lives. Secondly, I believe that cell phones are a fast and easy emergency resource for teens for the following three reasons. One of the reasons is if there is an emergency at home if is easy to get in contact with their kids. Another reason is sometime when teenagers are walking home alone and they feel as if they were being followed they sometimes pretend to act as if they were on talking to someone. Lastly, sometimes teenagers leave their school work at home they can easily text or call their parents and get them to bring their project to them. Therefore, for those reasons I believe cell phones are necessary in teen’s lives. Lastly, I believe that cell phone are an easy way to access internet and are entertainment for teens. One of the reasons is that cell phones have easy access to social networking sites. Sites like Facebook and Twitter can be used very accessible anywhere you go. Another reason is most phones have an application world, which allows them to pick from thousands of different applications to customize their phone. Lastly, with Wifi you can use the internet to go on any site at any time. Therefore, that is another reason why I believe cell phones are necessary in teens lives. In conclusion, I believe that cell phones are necessary in teen’s lives for the following three reasons. Firstly, they are a good social way to keep in contact with friends and family. Secondly, they are a fast and easy emergency resource. Thirdly, cell phones are an easy way to access the internet and they are entertainment to teens.

Study Case

CHAPTER 2I HUI4AN RESOURCE MANAGEMENT 903 Case Office Equipment Company (OEC) director (a U. S. national) of the office Equipment Company (oEc) in Lima, Peru (see Map 2l . l), announced suddenly that he would leave within one month. The company had to find a replacement. OEC manufactures a wide variety of small office 1997, the managing ln equipment (such as copying machines, recording machines, mail scales, and paper shredders) in eight different countries and distributes and sells products worldwide. lt has no manufacturing facilities in Peru but has been selling and servicing there since the early 1970s.OEC first tried selling in Peru through independent importers but quickly became convinced that in order to make sufficient sales it needed to have its own staffthere. Despite Peru's political turmoil, which at times has bordered on being a full-scale civil war, OEC'S operation there (with about 100 employees) has enjoyed good and improving sales and profitability. OEC is construct ing its first factory in Peru that is scheduled to begin operations in early 1999. This factory will import components for personal computer printers and assemble them locally.Peru offers an abundant supply of cheap labor, and the assembly oPeration will employ approximately 150 people. The government will allow up to I0 percent of the output to be sold locally. By assembling locally and then exporting, oEC expects to be able to ward off trade restrictions on the other office equipment it imports for sale within Peru. This plant! construction is being supervised by a U. S. rechnical ream, and a U. S. expatriate will be assigned to direct the production. This director will report directly to OEC's U. S. eadquarters on all production and quality-control matrers but will rePort to the managing director in Peru on all other matters, such as accounting, finance, and labor relations. OEC, by policy, will replace the exiting managing director with an internal candidate. The company employs a combination of home-, host-, and third-country nationals in top positions in foreign countries, and managers commonly rotate among foreign and U. S. locations. ln fact, it has been increasingly evident to OEC that international experience is an important factor in deciding who will be appointed to top corporate positions.The sales and service facility in Peru reports to a Latin American regional office located in Coral Gables, Florida. A committee at this office, charged with selecting the new managing direc- tor, quickly narrowed its choice to five candidates. Tom A thirty-year OEC veteran, Zimmerman is well versed in all the technical and sales aspects required in the job. He has never worked abroad for OEC but has visited various of the company's foreign facilities as part of sales teams. He is consid- Zimmerman ered competent and will retire in about four and a half years.Neither he nor his wife speaks Spanish. Their children are grown and living with their own children in th e United States. Zimmerman currently is in charge of an operation that is aboutthe size of that in Peru after the new factory begins operating. However, Zimmerman's present position will become redundant because the operation he heads is being merged with another. Brett Harrison Harrison, 40, has spent fifteen years at OEC. Considered highly compehas tent and capable of moving into upper-level management within the next few years, he 904 PART 7 FUNCTIONAL I'. ANAGEI'1 ENT, OPERATIONS. AND CONCERNS PERU Population 22. 3 million Monetary unit New sol Major languages Span ish Quech ua Aymara Largest city Lima Major industrial areas Arequipa Chimbote Cuzco lquitos Lima Talara Map 2l. l Peru never been based abroad but has worked for the last three years in the Latin American regional office and frequently travels to Latin America. Both he and his wife speak Spanish adequately, and their two children, ages I 4 and I 5, are just beginning to study the His wife holds a responsible marketin g position with a pharmaceuticals company.Carolyn language. Moyer Moyer joined OEC twelve years ago after getting her MBA from a pres- tigious university. 4t37, she has already moved between staffand line positions of growing responsibility. For two years, she was second in command of a product group that was aboutthe size of the newly expanded one in Peru. Her performance in that. postwas considered excellent. Currently, she works on a planning staffteam. When she joined OEC, she indicated her interest in eventual international responsibilities because of her undergraduate major in international affairs.She has recently expressed interest in international duties because of a belief it will help her advancement. She speaks Spanish well and is unmarried. Francisco Cabrera Cabrera, 35, currently is an assistant managing director in the larger Mexican operation, which produces and sells for the Mexican market. A Mexican cit- for OEC in Mexico for all his twelve years with the company. He holds an MBA from a Mexican university and is considered to be a likely candidate to head the Mexican operation when the present managing diiector retires in seven years. He is married with four children (ages 2 to 7) and speaks English adequately.His wife does not work izen, he has worked outside the home or speak English. CHAPTER 2I HUMAN RESOURCE MANAGEMENT 905 Juan Moreno At27, Moreno is assistant to the present managing director in Peru. He has held that position since joining OEC upon his U. S. college graduation four years ago. Unmarried, he is considered competent, especially in employee relations, but lacking in experience. He had been successful in increasing OEC's sales, in part because he is well connected with local families who can afford to buy new office equipment for their businesses. Questions l.Which candidate should ihe committee choose for the assignment, and whyl 2. What problems might each candidate encounter in the position? 3. 4. How might OEC go about mi nimizing the problems that each candidate would have in managing the Peruvian operations? Calculate an estimated compensation package for each candidate based on the following additional inf6rmation: Present annual salaries: Zimmerman, U5$70,000; Harrison, US$75,000; Moyer, US$65,000; Cabrera, M$ I 24,000; Moreno, 557,000 a Exchange rates: $ I: M$3. 1 (Mexican pesos);$ I: S 1. 9 (Peruvian new sols) o f income for a family of one, 40 percent for a family of two, 45 percent for a family of four, and 50 percent for a family of five or more: Washington, D. C. : 100; Lima : 86;Mexico City :77 U. S. Department, of State foreign-service premiums for Peru: hardship : l5 percent; danger: l5 percent U. S. Department of State cost-of-living index based on items covering 35 percent a a o Schooling allowance: age 6-12 : US$5000;age 3-18 : US$9000 Average tax rates: Mexico : 20 percenq United States : 25 percent; Peru : I Housing allowance (nontaxable): single : US$ 12,100;family : US$ 15,000 0 p ercent Chapter Notes l. The data for the case were taken from Edwin McDowell, â€Å"Making lt in America: The Foreign-Born Executive,† New York Times, June I, 1980, Section 3, p. l+; Don Whitehead, The Dow Story (New York McGraw-Hill, I968); â€Å"Lundeen Urges More Aid for Universities,† Chemrcal Marlceting Reporter, Yol. 224, No. 19, November 7, 1983, p. 3+;Paul L. Blocklyn, â€Å"Developing the lnternational Executive,† Personnel, Vol. 66, March 1989, pp. September 14,1992, p. 5; â€Å"Popoffon Challenges for Dow and for the lndusvy|' Chemical Wee( May 18, 1994, pp. 26-28; and Susan J.Sinsworth, â€Å"lssues Management ls Central to Frank Popoff's Globalization Strategy,† Chemlcol Engineering News, Vol. 72, No. 21, May 23, 1994, pp. 25–29. 2. Gary R. Oddou and Mark E. Mendenhall, â€Å"Succession Planning for the 2 l st Cen- European Management lournol, Yol. I 4, No. 4, August 1996, pp. 365-373. 4. â€Å"Globesmanship,† Across the Board , Yol. 27, Nos. l, 2, January-February 1990, p. 26, quoting Michael Angus. 5. Daniel Ondrack, â€Å"lnternational Transfers of Managers in North American and European MNEs,† Journol of lnternailonol Business Studies, Vol. 16, No. 3, Fall 1985, pp. l-19;andJohn M.Hannon, lngChung Huang, and Bih-Shiaw Jaw, â€Å"lnternational Human Resource Strategy and Its Determinants: The Case of Subsidiaries in Taiwan,†Journal of lnternotionol Business Studies, Vol. 26, No. 3, Third Quarter 1995, pp. 53 l-554. 4447; â€Å"Globesmanship,† Across the Boor4 Vol. 27, Nos. l,2,January-February 1990, pp. 24-34;William Storck, â€Å"Dow Chemical Changes Executive Lineup,† Chemical ond Engineering News, tury: How Well Are We Grooming Our Future Business Leadersl† Business Horizons, January-February I 99 I, pp. 26-34. 3. Gordon Petrash, â€Å"Dow's Journey to a Knowledge Value Management Culture,†

Puberty Of Hormones And Adult Physical Development

All teenagers experience huge changes physically and emotionally, called puberty. Puberty is â€Å"the time between the first onrush of hormones and full adult physical development. Puberty usually last three to five years† (Berger, 2014, p 319). Puberty generally starts between the ages 8 to 14. During these times children make the transition into adulthood. Not only do they grow in size, but also in sexual maturation. Inside the body many changes are occurring as well, such as the increase in hormone secretion. Hormones are â€Å"an organic chemical substance that is produced by one body tissue and conveyed via the bloodstream to another to affect some psychological function† (Berger, 2014, p 320). Hormones are responsible for regulating â€Å"hunger, sleep, mood, stress, sexual desire, immunity, reproduction, and many other bodily reactions, including puberty† (Berger, 2014, p 320). Two main hormones that increase drastically during puberty is estrogen, for g irls, and androgens, for boys. During the period of increase in these hormones, pubescent teenagers are more likely to develop psychological disorders, such as eating disorders, due to poor body image, causing long term issues physically and mentally. Eating disorders and body dissatisfactions are big issues in today’s society for teenagers and young adults. Eating disorders cause people to become so obsessed with their body image that they try to consume the least amount of food as possible. There are many different types ofShow MoreRelatedAdolescence : Everything Changes? Essay1199 Words   |  5 PagesAdolescence is a transitional stage of development that has been defined as starting with puberty and lasting the years a person is roughly aged ten to twenty. 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