Big Horn Engineering is designing a pneumatic conveyor for Premier Magnesia to increase material transport efficiency as well as reduce final product loss. The pneumatic conveyor must be able to deliver 325 mesh dry ground product at a rate of 15 tons/hr across the mine site and have a user-friendly operating system. The design and installation must be cost-effective and comply with Mine and Safety and Health Administration and the National Fire Protection Association.
Proof of Concept
Pneumatic conveying is an industry of its own and is currently a 30 billion USD market. The competition in this market is highly established companies with decades of experience in the field. Pneumatic Conveying Inc. is one of the top competitors for pneumatic conveying systems in the United States. This company serves major businesses such as Morton Salt, BF Goodrich, and Kraft Foods Inc. and designs all of its own machinery and systems. As more companies demand highly efficient material handling systems, the purchase of pneumatic conveying systems is expected to grow. The distribution of these systems is centered mainly on large manufacturing plants of food, chemicals, and other fine particles.
To compete in this industry, Big Horn Engineering is researching current patents and published journals on effective pneumatic conveying systems. The team is researching what materials to use, effective pressure systems, calculation methods, and is actively seeking help from experienced engineers with knowledge in the field.
Big Horn Engineering built a scaled pneumatic conveyor for the purpose of testing the amount of material able to be moved over a specified period of time. The conveyor consists of 1 in. PVC pipe and fittings, four 12-volt fans, a rotary airlock, and a funnel to direct airflow to the piping system. The material that was moved for testing was powdered coffee creamer, which had the most similar characteristics to that of the material that will be used at the mine site. The team ran three individual tests each lasting two and a half minutes. After the completion of each test, the amount of material moved from the load point to collection point was measured using a scale. A controlled testing environment and testing factors produced consistent results. The results collected proved a full-scale design can be implemented to move material at a desired constant mass flow rate.
The final design will be two systems— both are a pneumatic conveyor, conveying material in the dilute phase. The material conveyed is a 325 mesh magnesium product with a density of 3.58 g/cm3. In order to convey a material of this size and density, the pneumatic conveyor will require a pick-up velocity of 4,400 ft/s. The pipe used for this system will be 8 in. Schedule 40 structural steel. A flow rate of 1535 CFM is required to meet the pick up velocity requirements for the assigned diameter of the pipe. Pressure losses will amount to around 10 psi as they occur within the pipe due to the following: acceleration, gas frictional losses, solids through the pipeline, elevation changes, and miscellaneous equipment. In order to fulfill the CFM requirement and pressure losses, a pump must operate at 80 HP. In particular, a pump that fulfills the necessary requirements would be the Heliflow 616 with an 8 in. flange, maximum pressure of 12 psi, and maximum RPM of 3300. Such pump results in $15,000 as part of the cost.
There will be two seperate systems, one to move material to a hopper at the bottom of the plant, and the other to carry material from the bottom hopper to an upper hopper to account for overflow. Both systems have nearly identical paths and cover the same distance; thus, the same pump selected will be used for each individual system. A simple on/off switch will be used for the systems and an indicator, such as a light, to indicate when and which system is operating.
This system will eliminate the product loss Premier Magnesia currently faces, which is around 20%. It will also increase the rate at which they transport the material to the bottom or the top location. Currently, they utilize open trucking as their method of transporting the material. However, this approach is an open system that exposes the material to falling from the truck beds. The pneumatic conveyor creates a closed system that protects the product from the elements and eliminates unnecessary product loss. The conveyor will also save time by facilitating the ability to move the material quicker and eliminate the use of open trucking for the final product. The conveyor will minimize ground space on the plant, hence removing the need for the trucks to commute back and forth as all the pipes will be built above ground on an existing structure.
Testing and Results
Meet the Team
Karla Lopez is originally from California, but considers herself a Reno local, and is now a senior in Mechanical Engineering at the University of Nevada, Reno. Some of the projects she has been part of include the creation of a hovercraft and NXT-controlled Lego robots. Karla has served as a PASS Leader and helped with Dynamics over the past three semesters which have allowed her to sharpen her analytical, organization, and communication skills. Outside school and work, Karla enjoys spending her time serving the community. She volunteers at a free clinic for the uninsured and underinsured run by University of Nevada, Reno School of Medicine. After graduation, Karla intends to work and pursue an MBA or a master’s degree in systems engineering. She will use her skills to pave herself a secure, successful future.
Caryn Mao is from Las Vegas, Nevada and moved to Reno in 2015 to pursue a Bachelor of Science in Mechanical Engineering with a minor in Mathematics. During her academic career, she has improved upon program coding and applying critical thinking skills. Her most challenging engineering project was designing the installation of gas-main piping for her internship with Southwest Gas. Her proudest accomplishment is volunteering for the Nevada Food Bank and giving back to the community. Caryn plans to graduate in Spring and hopes to find a career that she enjoys and is passionate about and has a long-term goal of owning her own business.
Nathan Miller is from Danville, California and moved to Reno to attend University of Nevada, Reno. He is majoring in mechanical engineering and minoring in physics. Throughout his academic career, he has improved his ability to apply theoretical knowledge into practical application. The most challenging engineering project he has been involved in occurred when he was interning at Lawrence Livermore National Laboratory. The project was that a small sample of a specific powder had to be collected in an inert environment. With respect to analytical techniques, at the same internship, Miller developed a code that analyzed data for an optical probe dome. Outside of school, he is proud that he has given back to his hometown community by coaching a youth soccer team. Currently, his major goal is to learn as much as he can while in college that can aid him in his professional career, but after graduation his goal is to work for an established company that he is passionate about.
Brent’s most challenging engineering project he has been a part of would be the designing and building of a hovercraft in Engineering 100. This required plenty of team meetings to come up with a concept design, design analysis, and building of the final product. Brent has definitely improved on his presentation giving ability through many in-class presentations, as well as his time management skill through having to plan ahead to complete multiple assignments during any given week while still working a job and going to lectures. One of Brent’s most proud accomplishments was his successful replacement of head gaskets in an internal combustion engine, while figuring out more of how an internal combustion engine works in a modern everyday vehicle. Brent is currently enrolled in UNR planning to graduate in the spring of 2019 with a major in mechanical engineering and a minor in mathematics. He then plans on getting a job with a company where he can spend the rest of his life until he retires with a lot of money.
Colin Thompson is from Girdwood, Alaska and is pursuing a Bachelor degree in mechanical engineering from the University of Reno, Nevada. One of the largest and most challenging engineering projects Colin has been a part of is the design of a hovercraft through the university’s introduction to engineering class. Through other group projects, communication and teamwork skills were acquired. Colin looks to continue to push himself in and out of the classroom, and later find a career as a design engineer in Reno.