The total cost of desulfurization equipment consists of production costs and financial expenses. The production cost mainly includes material consumption during the production period (such as desulfurizer consumption, water consumption, electricity consumption, steam consumption, etc.), labor costs, repair costs, operation and management fees, insurance premiums, fixed asset depreciation costs, etc. Financial expenses
Mainly including long-term loan interest, short-term loan interest, and working capital loan interest. The depreciation cost of fixed assets depends on the dynamic investment of desulfurization projects. The economic evaluation of desulfurization devices can be mainly divided into two aspects: first, the desulfurization cost per unit of power supply (yuan/MW · h); The second is the cost of removing sulfur dioxide per unit mass.
In order to obtain a reasonable operating cost for desulfurization at the average social level, this statistical calculation uses data from the average social level of Guangdong Province for parameters that are not directly related to the desulfurization device. The parameters determined using social average level data are as follows: the construction period of the desulfurization device is 2 years, with 70% of the construction funds used in the first year; Annual utilization hours of desulfurization device: 5500 hours; Factory electricity price: 0.39 yuan/kW · h (excluding tax, selected based on the average electricity price of coal-fired units belonging to a power generation group in Guangdong Province in 2004); Price of desulfurizer: 250 yuan/t for limestone powder, 150 yuan/t for limestone, and 350 yuan/t for hydrated lime; The water price is 3 yuan/ton; Steam price is 35 yuan/t; Unit staffing: 25 people for one desulfurization unit, with an additional 5 people for each additional unit; The annual per capita salary is 65000 yuan/person · year, with a welfare coefficient of 60%; Prepaid repair rate of 3.0%; Operation and management expenses are 0.6 yuan/MW · h; Insurance premium rate of 0.25%; The production and operation period of the desulfurization device is 20 years; Depreciation period of desulfurization unit is 12 years; Fixed asset formation rate of 95%; The proportion of self owned funds for desulfurization project investment is 25%; The annual interest rate for loans during the construction period is 6.12%; The loan repayment period is 12 years; The annual interest rate for working capital loans is 5.58%.
The cost of flue gas desulfurization in thermal power plants is enormous, with an average total cost of 1.38 billion yuan during the 20-year operation period of each project. The highest reached 2.49 billion yuan, and the lowest also reached 410 million yuan. The average cost of power supply desulfurization per MW · h for each project is 17.20 yuan/MW · h, with the highest reaching 28.18 yuan/MW · h and the lowest reaching 12.03 yuan/MW · h, a difference of 2.3 times. The average cost per kilogram of SO2 for each project is 2.99 yuan/kg. The highest reaches 4.50 yuan/kg; The lowest cost is only 1.10 yuan/kg. The difference between the two is as much as 4.1 times.
Due to the high fuel prices and corresponding electricity prices in Guangdong Province, electricity has become the main cost of desulfurization equipment in Guangdong Province, accounting for 26.8% of the total cost. Next are fixed asset depreciation costs, desulfurizer costs, and repair costs, accounting for 22.7%, 16.3%, and 14.4% of the cost, respectively. Other expenses account for 19.8%.
Unit capacity, construction period of desulfurization project, fuel characteristics, annual utilization hours of desulfurization equipment, desulfurization process, etc. are the main factors affecting the unit power supply desulfurization cost.
Fuel characteristics are the decisive factor affecting the cost of SO2 removal per unit mass. Priority should be given to flue gas desulfurization of units with high fuel sulfur content to reduce the cost of environmental remediation. The cost of delivering 0 # diesel to the factory and to the boiler is 5000 yuan/t. The coal is then sent to the boiler to be made into coal powder, with a low calorific value of 20000 kJ/kg, which is about 420 yuan/t (the low calorific value of coal is 18100 kJ/kg, which is about 382 yuan/t, calculated at a unit price of 420 yuan/t). It can be calculated that one cold furnace operation saves about 253000 yuan in fuel costs. Similarly, there are good fuel saving benefits in warm, hot, and low load stable combustion conditions. After comparing the retrofitting of two boilers, at least 1000 tons of fuel can be saved annually due to the start stop operation of combustion assistance. Deducting the cost of coal powder combustion can save 4.12 million yuan per year, and the benefits are considerable.
