Comparison of electric heating cable and steam heating cable

(1) Electric heating belt: self-controlled electric heating belt, voltage 220V, heating temperature is 5 degrees Celsius. Since the time is spent on improving the heat resistance of the electric heating belt of the steam pipe, it is necessary to develop electric heating belts with the advantages of anti-aging and low attenuation (the insulating metal sheath is fluoroplastic, and the core is fluorine-containing material). The total length is about 35 yuan/m. The material cost is generally 1000×35=35,000 yuan; the installation cost (mainly through labor wages) is 1000×3=3000 yuan per m3.

(2) Power supply and distribution system: The material cost including the distribution cabinet and transmission line is 33,000 yuan. Silicone rubber heating plate heating element: The nickel alloy heating wire is wrapped around the glass fiber, and the heating power can reach 2.1W/c㎡, and the heating is more uniform. Moisture-proof and chemical-resistant silicone rubber materials provide longer heater life. Pressure-sensitive adhesive can be used for bonding on flat and smooth workpieces. Lithium battery heaters have basic functions, such as heating, constant temperature, and temperature control. Battery energy storage heaters are thin, light and flexible. With this heater, you can transfer heat to any place you need it. During processing, it improves heat transfer, accelerates heating and reduces power requirements.

2. Steam tracing

(1) Heating pipe: 1 DN20 heating steel pipe is selected according to process requirements. The total weight of the pipe is 1000 meters and the total weight is 2.27 tons (DN20, 2.27KG/m). If the unit price is 5000 yuan/ton, the material cost is 5000×2.27×11350 yuan, and the installation fee (including installation materials and labor wages) is 7850 yuan.

(2) Steam supply pipeline: DN100 gas supply pipeline is selected, with a total length of 1000m, material cost of 102180 yuan, and installation fee (including installation materials and labor wages) of 40423 yuan.

(3) Steam supply pipe insulation: 50mm thick rock wool is selected, and the outer protective layer is a galvanized iron sheet with a total length of 1000m. The estimated material cost is 20,250 yuan and the installation cost is 44,200 yuan.

(4) Water supply and drainage system: including steam supply valve, heating pipe steam supply valve, steam trap stop valve, steam trap and steam trap check valve, etc., the cost is 2,550 yuan.

III. Comparison of operating costs

(1) Steam consumption cost of pipeline heating: The heat consumption of the instrument for pipeline heating and the steam consumption of the steam supply pipeline are 0.30t/h, and the steam consumption per ton is 50 yuan. The operating days are 100 days, and the annual steam consumption cost is 0.3×100×24×50=36,000 yuan.

(2) The maintenance cost of the heating pipeline includes line inspection, maintenance and renewal, as well as various maintenance costs, which is about 42,000 yuan per year.

IV. After-sales consumption

(1) Power consumption

The most widely used automatic power supply hot line consumes 15W per meter. The total length of the pipeline is 1000 meters, and the power consumption per hour is 1000×15/1000 x 15kW.h. When the pipeline temperature reaches the maximum maintenance temperature, the heat generated by the electric heating will gradually decrease, and the output power will also decrease, thereby reducing the power consumption of the heating. Generally, 60% of the rated power, the factory electricity price is calculated at 0.20 yuan/kWh, and the operating days are 100 days (2400 hours), then the normal annual electricity cost is: (15×2400)×0.20×60%

(2) Maintenance cost

Automatic temperature control electric heating requires almost no maintenance. According to regulations, it only needs to measure the insulation with a shaker every year, which is estimated to be 10,000 yuan/year.

V. In summary

The investment in electric heating is 70% of steam heating, but the operating cost is 4 times that of electric heating. The output effects of the two schemes are the same, and both can meet the insulation and antifreeze requirements of instrument pipelines. Therefore, the annual costs of the two schemes can be compared and analyzed (the economic life of steam heating is 10 years, and the economic life of electric heating is 12 years). According to the calculation results:

The annual cost of the steam heating scheme is:

Annual depreciation cost + annual operation and management cost = 228803/10 + 78000 = 100880.