Today, the use of nitrogen in factories is usually nitrogen and liquid nitrogen, Shenzhen Troy New Energy Co., Ltd. has made a comparison of the cost of nitrogen and liquid nitrogen, so that the factory can reasonably choose the use of nitrogen or liquid nitrogen
The nitrogen production project is calculated according to the application requirements of 30Nm3/h and 99.999% nitrogen purity

1. The operating cost of bottle nitrogen

Usually the market purity of 99.999% of nitrogen quote is 50 yuan/bottle, a bottle of nitrogen under 12Mpa pressure standard volume is 40 liters, in practice as long as 5M3 per bottle, so calculated, that is, per cubic meter of general nitrogen quote is 10 yuan. This method of gas use is only suitable for users with very small gas consumption.

The cost of using cylinder nitrogen: 30Nm3/h x 10 yuan =300 yuan/hour

Annual operating cost: 300×8000 hours/year = 2.4 million yuan/year

2, the operating cost of liquid nitrogen

The price of liquid nitrogen with a purity of 99.999% on the market is 1500 yuan/ton, a ton of liquid nitrogen can be vaporized to 600 cubic meters of gaseous nitrogen, and the price per cubic meter of nitrogen is 2.5 yuan. (Excluding the initial input of liquid nitrogen storage tank, carburetor, annual maintenance, labor costs)

The cost of using liquid nitrogen: 30Nm3/h x 2.5 yuan =75 yuan/hour
Annual operating cost: 75×8000 hours/year = 600,000 yuan/year

3. Operating cost of on-site nitrogen production (calculated according to 30Nm3/h of your company's nitrogen production project)

The operating cost of the system mainly consists of the following aspects:

1, electricity consumption 2, labor 3, equipment protection costs 4, depreciation of equipment

The consumption of electric energy mainly comes from the following aspects:

Air compressor: The rated power of the air compressor is 15kw, because the unloading of the air compressor and the appropriate compressed air margin are taken into account when the system is selected, the practical power consumption of the air compressor is about 60% of the rated power, that is, 9kw.

Freeze dryer: The rated power of the freeze dryer is 0.58kw.

Nitrogen machine: the material of the nitrogen machine is compressed air, and the nitrogen machine itself basically does not consume electricity, the first is the meter electricity, the rated power is about 0.6kw.

Nitrogen purification power: Power 6Kw

In summary, the power of the entire nitrogen production system is 17kw

Assuming that the electricity charge is 0.7 yuan /kwh, then the electricity consumption per hour is 17×0.7=12 yuan

Nitrogen power consumption per cubic product: 12÷30=0.4 yuan

Operating fee: 30Nm3/h×0.4 yuan =12 yuan/hour (electricity)

Annual operating cost: 12×8000 hours/year = 96,000 yuan/year (electricity)

Labor cost: Because the equipment does not require special personnel to perform regular and irregular inspections, the labor cost of the gas equipment can be calculated according to 20 yuan per day when calculating the operating cost.

Equipment protection and maintenance costs:

The main body of machine protection and maintenance costs is now:

Air compressor



Air filter cartridge: Replace once every 4000 hours Unit price: 445 yuan/piece



Oil and gas filter element: replace once every 8000 hours unit price: 480 yuan/piece



Oil filter element: Replace once every 2000 hours Unit price: 346 yuan/piece



Lubricating oil: Replace once every 2000 hours Unit price: 350 yuan/time



Compressed air filter C, T, A three filtration



Replacement every 4000 hours: 600/3



Nitrogen machine: oxygen analyzer probe: replace once every two years Unit price: 580 yuan/piece



Nitrogen purification: The whole equipment does not need to replace parts, only the stability of the components can be checked frequently.



Depreciation of equipment: the depreciation period of equipment is ten years



4, nitrogen system PD5N-30Nm3/h total investment of 172,400 yuan (including screw air compressor system)



1), the cost of using cylinder nitrogen:



The cost of using cylinder nitrogen: 30Nm3/h x 10 yuan =300 yuan/hour



Annual operating cost: 300×8000 hours/year = 2.4 million yuan/year (excluding the bus equipment and pressure reducing valve and manual operation cost invested in the early period)



2) Operating costs of liquid nitrogen



The cost of using liquid nitrogen: 30Nm3/h x 2.5 yuan =75 yuan/hour



Annual operating cost: 75×8000 hours/year = 600,000 yuan/year (excluding the initial input of liquid nitrogen tank, carburetor, bus equipment and pressure reducing valve and manual operation costs)



3) Cost of nitrogen production system:



Electricity + labor + equipment protection and maintenance + depreciation of equipment



Annual operating fee: 96,000 yuan/year (electricity) + 7,200 yuan/year (labor) + 2,830 yuan/year (protection and maintenance) + 18,000 yuan/year (depreciation) = 124,000 yuan/year



4) Annual cylinder nitrogen cost: 2.4 million yuan/year



Annual use of liquid nitrogen cost: 600,000 yuan/year



Annual use of nitrogen machine cost: 124,000 yuan/year