Project Based Learning of the Engineering Method V: A Hemodialysis System Design Project Young Engineers and Scientists Seminars Historical Electronics Museum Taryn Melkus Bayles, Ph.D. and Tania Monterastelli Chemical and Biochemical Engineering Department University of Maryland Baltimore County December 13, 2007

Reach for the Stars! Design Challenge Design and construct a self supporting structure for the least amount of money: Height (inches) Cost ($) Team Name Height (in) Cost ($) Bragging Rights Team Ballin Quanta The Fluffy Giraffes

EEK! Don’t Let It Leak! Design Challenge Design and construct a device which will protect an egg when it is dropped from a 10 foot height. 1. Mass (g) Cost ($) Team Name Mass (g) Cost ($) Bragging Rights 4 Asians & A White Guy The Alliance DP

Separate This!! Design Challenge Design and construct a device or series of devices to separate the blue sand from the mixture while maximizing the amount of blue sand recovered Final Mass (g) Initial Mass (g) Team Name Final Mass (g) Initial Mass (g) Bragging Rights Sunny’s MMB Asian, Jew, Hippee, Albino & Guido

Snap Krackle and Pop!! Design Challenge Design and construct a device or series of devices to separate the Rice Krispies from the mixture of breakfast cereal while maximizing the amount of Rice Krispies recovered and minimizing cost Team Name % Recovery Cost (¢) Bragging Rights MMB Asians & A White Guy We give up and went home

YESS Program Mini Design Challenge: Let It Flow! Design and construct an apparatus to transfer 500 ml of water a distance of 4 feet as quickly as possible while minimizing the cost of the apparatus. Use only the materials provided –Three different diameter tubing (each are 2 feet long), funnels, plastic ties, rubber hose connectors, empty 500 ml bottle –You may not cut the tubing Final volume (ml) / initial volume (ml) [ time (s) x cost ($) ]

Let It Flow! Design Challenge:

Let it Flow!! Design Challenge Design and construct a device which will transport 500 ml of water a distance of 4 feet as quickly as possible. Team Name % Recovery Time (sec) Cost ($) Bragging Rights Blood Donors The Alliance Three Guys

YESS Program Design Project –Bragging Rights: Removal of impurities (mg) x Dialysate $ index x System $ Index

YESS Program Design Project How to Design a Hemodialysis System? –Factors that influence system performance: Diffusion of impurities –Concentration –Temperature –Molecule size Dialysis membranes –Pore size –Surface area Simulated blood flow rate Dialysate flow rate Co-current/Counter-current flow

YESS Program Design Project Hemodialysis System Product Performance Bragging Rights Impurity removal - mg x dialysate cost index x device cost index –Cost Basis: –Choice of four membranes 6.37 mm Diameter MW cut off $3.05/ft 16 mm Diameter MW cut off $4.20/ft 12.1 mm Diameter and 3500 MW cut off $2.84/ft 16 mm Diameter and 3500 MW cut off $3.22/ft –Dialysate cost is $20.00 per liter –Cost index Dialysate cost index –Minimum dialysate cost that meets design specifications Team dialysate cost Device cost index –Minimum total system cost meets design specifications Team total system cost

YESS Program Design Project How do you make the Simulated Blood and the Dialysate Flow? –Pump –Gravity –Mathematical relationship Relates pressure, velocity and height Bernoulli equation

YESS Program Design Project Removal of Impurities –Tartrazine Dilution Standards

YESS Program Design Project Removal of Impurities –Visual Comparison is made –Concentration x Dialysate Quantity

YESS Program Design Project Examples of Hemodialysis Systems

YESS Program Design Project Examples of Hemodialysis Systems

YESS Program Design Project Examples of Hemodialysis Systems

YESS Program Design Project

For Tonight’s YESS Design Session –Design notebook –Complete Hemodialysis Design Project Sheet Team Name, High School, Team Members & s –“Purchase” membrane Membrane pore size, diameter – surface area, length, cost –Each team will be given 500 ml of simulated blood for practice testing Old clothes Gloves –How you will flow BOTH the blood and dialysate –How will you determine the amount of impurities that you have removed? Volume of dialysate used Concentration of dialysate at end of testing