added subject for fuel mass explanation

scenario_specifcation.md

@@ -60,8 +60,9 @@ $
             \end{tabular}
             \end {table}
 $
-For 100 GW-year (250 FR-year), uses 1,257,400 kg of fuel  
--> 1 FR spends 1,257,400/250 * (14/12) = **5867 kg / Batch**  
+For 100 GW-year (250 FR-year) the SFR fleet uses 1.25e6 kg of fuel.
+1 FR spends 1,257,400/250 = 5,029 kg / year
+Since a batch is replaced every 14 months, the mass of a batch is: 5,029 * (14/12) = **5,867 kg / Batch **
 
 Refueling frequency: 14 months  
 Refueling time: 1 month
@@ -87,10 +88,9 @@ $
             \end {table}
 $
 
-
-
-For 100 GW-year (250 FR-year), uses 1,251,200 kg of fuel  
--> 1 FR spends 1,251,200/250 * (14/12) = **5838 kg / Batch**  
+ For 100 GW-year (250 FR-year) the SFR fleet uses 1.25e6 kg of fuel.
+1 FR spends 1,251,200/250 = 5,004 kg / year
+Since a batch is replaced every 14 months, the mass of a batch is: 5,004 * (14/12) = **5,838 kg / Batch **
 
 Refueling frequency: 14 months  
 Refueling time: 1 month
@@ -117,14 +117,17 @@ $
 $
 
 **FR:**
-For 61.08 GW-year (152 FR-year), uses 1,206,900 kg of fuel  
--> 1 FR spends 1,206,900/152 * (14/12) = **9263 kg / Batch**  
+
+For 61.08 GW-year (152 FR-year) the SFR fleet uses 1.206e6 kg of fuel.
+1 FR spends 1,206,900/152 = 7,940 kg / year
+Since a batch is replaced every 14 months, the mass of a batch is: 5,029 * (14/12) = **9,263 kg / Batch **
 Refueling frequency: 14 months  
 Refueling time: 1 month
 
 **MOX LWR:**
-For 38.92 GW-year (39 LWR-year), uses 861,400 kg of fuel  
--> 1 MOX LWR spends 861,400/39 * (18/12) = **33130 kg / Batch**  
+For 38.92 GW-year (39 LWR-year), the MOX LWR fleet uses 8.6e5 kg of fuel.
+1 MOX LWR spends 861,400/39 = 22,087 kg / year
+Since a batch is replaced every 18 months, the mass of a batch is: 22,087 * (18/12) = **33130 kg / Batch **
 Refueling frequency: 18 months  
 Refueling time: 1 month
 
@@ -150,22 +153,17 @@ $
             \end {table}
 $
 
-| Category  | Driver| Blanket | MOX | 
-| :-------------: |:-------------:| :-----:|  :-----:|
-| Material | TRU / Rep U / Nat U | Rep U / Nat U | TRU / Rep U |
-| Burnup | 107 Gwd/t | 23 Gwd/t | 50 GWd/t | 
-| Composition | 24.4 % TRU | .15 % U235 | 10.4 % TRU |  
-| Fuel Residence Time | 4.9 years (avg) | 3.9 years |
-| Normalized % | 47 %  | 53 % | 100% |
-
-**FR:**  
-For 87.0 GW-year (218 FR-year), uses 1,218,300 kg of fuel  
--> 1 FR spends 1,218,300/218 * (14/12) = **6519 kg / Batch**    
+**FR:**
+
+For 87.0 GW-year (218 FR-year) the SFR fleet uses 1.218e6 kg of fuel.
+1 FR spends 1,218,300/218 = 5,588 kg / year
+Since a batch is replaced every 14 months, the mass of a batch is: 5,588 * (14/12) = **6,519 kg / Batch **
 Refueling frequency: 14 months  
 Refueling time: 1 month
 
-**MOX LWR:**  
-For 13 GW-year (13 LWR-year), uses 287,000 kg of fuel  
--> 1 MOX LWR spends 287,000/13 * (18/12) = **33115 kg / Batch**    
+**MOX LWR:**
+For 13 GW-year (13 LWR-year), the MOX LWR fleet uses 2.87e5 kg of fuel.
+1 MOX LWR spends 287,000/13 = 22,076 kg / year
+Since a batch is replaced every 18 months, the mass of a batch is: 22,076 * (18/12) = **33115 kg / Batch **
 Refueling frequency: 18 months  
 Refueling time: 1 month