Pounds per cubic feet to kilograms per cubic meter

OADVANCED SOLID WASTE MANAGEMENT UNIT 3

kay, I’m just going to briefly go over the way we do these conversions. So in this problem, you’re a consultant, and your client is giving you literature that they have received from two manufacturers of shredder equipment. The bulk density specification of Unit A is 35.7 pounds per cubic foot, and that means cubic foot right there, and the bulk density of Unit “B” is 450 kilograms per cubic meter. Which unit will deliver a higher bulk density refuse? Show your work. And then, Part B asks referring to the diagram below, how far above the floor is the bulk density of the stored MSW, municipal solid waste, compressed to 250 kilogram per cubic meter? Okay, so let’s look at Part A first before we look at the diagram for Part B. Alright, we’re going to convert the 35.7 pounds per cubic feet to the same units as kilograms per cubic meter. Okay, so you go to your conversion table in the back of your book, and you look up 1 pound is equivalent to 0.454 kilograms and the same with the cubic feet. One cubic foot is equivalent to 0.0283 cubic meters. Okay, so we’re going to set up the calculation. This is also known as dimensional analysis. You’re literally, the whole purpose of setting it up like this is to eliminate—cross out your units. We start with 35.7 pounds per cubic feet. Notice that as I set this up, we have pounds per cubic feet; notice my 1 cubic foot is similar to .0283 because I can literally just eliminate my cubic feet, now I’m left with cubic meters. Notice the same thing with the pounds and the kilograms. Notice over here the pound is in the denominator and this pound is in the numerator; it cancels each other out. And what are we left with? Once we do all the math, we’re left with kilograms per cubic meter. And you would literally just, you would do this, you would calculate this by taking 35.7, multiplying it by 0.454. I would press equal on my calculator and then I would divide by .0283 press equal, and you’ll get something like that, okay? And Part B, let’s see what it says. It says, referring to the diagram below, how far about the floor—this is what they’re talking about—is the bulk density of the stored MSW compressed 250 kilograms per cubic meter? I’m going to try to make this a little larger so you can see it. So over here, these numbers in parentheses represent the feet. The numbers here represent our meters. And this is, it says stored material height above the floor, so this would be 10 meters or 32.8 feet above the floor. The X-axis, right here, these numbers here, represent the stored material, the density of the stored material in kilograms per cubic meter which is the zero, 100, 200, etc. and the correlating pounds per cubic feet are in parentheses. So the question asks us, how far above the floor is the bulk density of the stored MSW compressed to 250 kilograms. So if I were to look at this, I would go, I know that this is approximately—I’m just going to say 250 is about right here. Alright, and I notice that if I drew a line here, it looks like that might be halfway, okay? So let’s see how we calculated that. So, I kind of said two and a half meters, and we know that one meter is approximately 3.28 feet. Notice how my units of that say meter, cancel out, and I’m left with feet. And all I’m doing is multiplying 2.5 times 3.28 and to get approximately 8.2 feet above the ground.