ECONOMIC ANALYSIS OF DRYERS
7.4 COST ANALYSIS OF THREE DRYERS
In this section, the cost analysis of three dryers is investigated. The fixed cost, variable cost, selling price, payback period and profit per year were all determined. When performing cost analysis, numerous assumptions associated with various costs were taken into account. The assumptions were taken based on the experimental evaluations and market survey conducted in Assam, the North-Eastern region of India. The assumptions for the cost of paddy drying computation are shown in Table 7.1.
Table 7.1 Different costs for the three dryers Calculation
parameters
Conical dryer (α = 10°)
Conical dryer (α = 5°)
Cylindrical dryer (α = 0°)
Wet paddy rate (100 kg) Rs. 1200.00 Rs. 1200.00 Rs. 1200.00 Dry paddy rate (100 kg) Rs. 2000.00 Rs. 2000.00 Rs. 2000.00
Electricity kWh @ 5.10 @ 5.10 @ 5.10
Unskilled Labour Rs. 313.00/day Rs. 313.00/day Rs. 313.00/day Interest rate 10% of investment 10% of investment 10% of investment Repair & Maintenance 5% of investment 5% of investment 5% of investment Dryer Utilization 300 days/year 300 days/year 300 days/year
Dryer Cost Rs. 15000.00 Rs. 13500.00 Rs. 13000.00
Dryer service life 10 years 10 years 10 years
Instrumentation Rs. 25000.00 Rs. 25000.00 Rs. 25000.00
Drying of paddy @ hour 10 kg 8 kg 5 kg
Dryer running 8 hours 51 kg/day 43 kg/day 36 kg/day
Drying time 28 mins 33 mins 40 mins
7.4.1 Cost analysis of conical dryer with cone angle 10°
The blower mass flow rate and electric heater power were calculated by the following equation CFM 1.75 (Watt / Temperature Difference)= (7.5) According to the above formula, the use of total electricity used for one hour was 2.5 kW for the drying paddy.
Total cost of dryer = Dryer + Investment (cost) = Rs. (15000.00 + 25000.00) = Rs. 40,000.00.
Assuming the total life span of the dryer as 10 years.
The total interest of investment per year @10% = Rs. 4,000.00.
So, for one year, the fixed and the interest cost will be equal to Rs. 4,000.00.
So, the total fixed cost for one year = Rs. (4000.00 + 4000.00) = Rs. 8000.00.
Annual maintenance and repairing cost @ 5% of investment = Rs. 2,000.00.
After calculating the annual expenditure, the one-day expenditure for drying of paddy in the conical dryer of 10° cone angle is evaluated by dividing the number of days and shown in Table 7.2, which helps to determine the annual profit and BEP.
Table 7.2 One day expenditure for drying of paddy in the conical dryer (α = 10°)
Parameters Cost
Fixed cost per day Rs. 27.00
Maintenance per day Rs. 7.00
Electricity per day Rs. 102.00
Unskilled labour per day Rs. 313.00 Total expenditure per day Rs. 449.00
For one day, a total of 51 kg of paddy is dried with the expenditure of Rs. 449.00.
The cost of a dryer per kg of paddy is Rs. 8.80.
The total collected dry paddy is 38 kg from 51 kg of wet paddy.
The volume of dry paddy in one year is 38×300 = 11400 kg.
The selling price of dry paddy per kg is more than that of wet paddy by twenty rupees.
Therefore, total money collected by selling 38 kg @ Rs 20.00 = Rs. 760.00.
Profit = Selling price of paddy - Expenditure price for drying of paddy.
Profit = Rs. 760.00 - Rs. 449.00 = Rs. 311.00 per day
Therefore, (considering 300 days as working days), the profit will be Rs. 311.00 × 300 = Rs.
93400.00.
Payback period or BEP (Break-even period):
* A
N = S (7.6)
where, S is the net annual saving or profit, A is the capital cost or investment per year, and N* is the payback period per year.
N* = 40,000.00/93,400.00 = 0.43.
The cost of one kg wet paddy and the payback period is Rs. 8.80 and 0.43 years, respectively.
7.4.2 Cost analysis of conical dryer with cone angle 5°
Total cost of dryer = Dryer + Investment (cost) = Rs. (13500.00 + 25000.00) = Rs. 38,500.00.
Assuming the total life span of the dryer as 10 yrs.
The total interest of investment per year @10% = Rs. 3,850.00.
So, for one year, the fixed and the interest cost will be equal to Rs. 3,850.00.
So, the total fixed cost for one year = Rs. (3850.00 + 3850.00) = Rs. 7,700.00.
Annual maintenance and repairing cost @5% of investment = Rs. 1,925.00.
Similar to Table 7.2, one-day expenditure for paddy drying in the conical dryer of 5° cone angle is also calculated by dividing the number of days to determine the annual profit and BEP and is shown in Table 7.3
Table 7.3 One day expenditure for drying of paddy in the conical dryer (α = 5°)
Parameters Cost
Fixed cost per day Rs. 25.00
Maintenance per day Rs. 6.00
Electricity per day Rs. 102.00
Unskilled labour per day Rs. 313.00 Total expenditure per day Rs. 446.00
For one day, a total of 43 kg of paddy is dried with the expenditure of Rs. 446.00.
The cost of a dryer per kg of paddy is Rs. 10.37.
The total collected dry paddy is 35 kg from 43 kg of wet paddy.
The volume of dry paddy in one year is 35×300 = 10500 kg.
Total collected dry paddy per kg is more than that of wet paddy by twenty rupees. Therefore, total money collected by selling 35 kg @Rs 20.00 = Rs. 700.00.
Profit = Selling price of paddy - Expenditure price for drying of paddy = Rs. 700.00 - Rs. 446.00 = Rs. 254.00 per day.
Therefore, (considering 300 days as working days), the profit will be Rs. 254.00 × 300 = Rs.
76,200.00.
Payback period or BEP (Break-even period):
N*= 38,500.00/76,200.00 = 0.505
The cost of one kg wet paddy and the payback period is Rs 10.37 and 0.505 years, respectively.
7.4.3 Cost analysis of cylindrical dryer (α = 0°)
Total cost of Dryer = Dryer + Investment (cost) = Rs. (13,000.00 + 22,000.00) = Rs. 35,000.00.
Assuming the total life span of the dryer as 10 years.
The total interest of investment per year @10% = Rs. 3,500.00.
So, for one year, the fixed and the interest cost will be equal to Rs. 3,500.00.
So, the total fixed cost for one year = Rs. (3500.00 + 3500.00) = Rs. 7000.00.
Annual maintenance and repairing cost @5% of investment = Rs. 1,750.00.
Analogous to Tables 7.2 and 7.3, one-day expenditure for drying of paddy in the cylindrical dryer is shown in Table 7.4 to determine the annual profit and BEP.
Table 7.4 One day expenditure for drying of paddy in the cylindrical dryer (α = 0°)
Parameters Cost
Fixed cost per day Rs. 23.00
Maintenance per day Rs. 5.00
Electricity per day Rs. 102.00
Unskilled labour per day Rs. 313.00 Total expenditure per day Rs. 443.00 For one day, a total of 36 kg paddy is dried with the expenditure of Rs. 443.00.
The cost of a dryer per kg of paddy is Rs. 12.33.
The total collected dry paddy is 28 kg from 36 kg of wet paddy.
The volume of dry paddy in one year is 28×300 = 8400 kg
Total collected dry paddy per kg is more than that of wet paddy by twenty rupees. Therefore, total money collected by selling 28 kg @Rs 20.00 = Rs. 560.00.
Profit = Selling price of paddy - Expenditure price for drying of paddy = Rs. 560.00 - Rs. 443.00 = Rs. 117.00 per day
Therefore, (considering 300 days as working days), the profit will be Rs. 117.00 × 300 = Rs.
35100.00.
Payback period or BEP (Break-even period):
N*= 35,000.00/35,100.00 = 0.997
The cost of one kg wet paddy and the payback period is Rs 12.33 and 0.997 years, respectively.
After calculating all the parameters, the economics of dryers are presented in Table 7.5.
Table 7.5 Economics of dryers Calculation
parameters
Conical dryer (α = 10°)
Conical dryer (α = 5°)
Cylindrical dryer (α = 0°)
Total cost of a dryer Rs. 40,000.00 Rs. 38,500.00 Rs. 35,000.00 Total fixed cost/ year Rs. 8000.00 Rs. 7,700.00 Rs. 7,000.00
Profit/day Rs. 311.00 Rs. 254.00 Rs. 117.00
Profit/year Rs. 93400.00 Rs. 76,200.00 Rs. 35100.00
BEP 0.43 0.505 0.997
The BEP was found to be lower than Yahya et al. (2016) [197], Singh (2021) [198] and Pati (2016) [199] and profit/year was found to be higher than that of Yahya et al. (2016) [197],
Singh (2021) [198] and Pati (2016) [199]. The reason for this is due to the enhanced drying characteristics and consumption of less energy in the context of bubbling fluidized bed dryers.