The unit power consumption of oxygen production W02 (kW • h/m3) is one of the important economic indicators of oxygen production. InAir separation equipmentIn oxygen generation power consumption,Air compressorPower consumption accounts for the most important part. Its power consumption (kw • h/h) is related to the pressure ratio, and the calculation formula is
W=ρvk R′Tln(p2/p1)/(3600ηTηM)
In the formula & rho; -- air density under standard state, & rho; = 1.293 kg/m3;
Vk -- air displacement of air compressor, m3/h;
R & prime; -- gas constant, R & prime; = 0. 278kJ/(kg • K );
T -- ambient temperature, K;
P2 -- exhaust pressure, MPa;
P1 -- air inlet pressure, MPa;
& Eta; T -- the isotherm efficiency of the air compressor;
& Eta; M-the mechanical efficiency of the air compressor.
Therefore, the unit power consumption e02 (kW • h/m3) of compressed air consumed during oxygen generation is
e02= vkρ R′Tln(p2/p1)/( Vo23600ηTηM)
In the formula, Vo2 -- oxygen output, m3/h.
However, the extraction rate of oxygen (see question 20) is
ψ=Vo2•yo2/( Vk•yk)
So
e02= yo2ρ R′Tln(p2/p1)/( ψyk 3600ηTηM)
Thus it can be seen that the unit power consumption of oxygen generation is roughly proportional to the logarithm of pressure ratio and the purity of oxygen; it is inversely proportional to the extraction rate of oxygen and the efficiency of compressor. Therefore, during the operation, the working pressure should be reduced as much as possible; the compressor should be fully cooled to improve the isotherm efficiency of the compressor; the oxygen extraction rate should be improved as much as possible; on the premise of ensuring the product quality, do not pursue product purity too high, in order to reduce unit power consumption.
