METHOD OF DETERMINING SOFTENING TEMPERATURE OF HEAVY PETROLEUM PRODUCTS Russian patent published in 1999 - IPC

FIELD: rheological examination of materials. SUBSTANCE: invention relates to application of NMR technique for rheological examination of materials and can be used to determine softening temperature of heavy petroleum products such as goudrons, mazuts, bitumens, cracking residues, oil sands, etc. Sampled product is affected by electromagnetic emission and NMR characteristics are registered. Invention is distinguished by that NMR transmitter is filled with excess of oil product and electromagnetic action is effected by imposing a series of radio-frequency pulses on product at constant temperature not below its plastic state temperature. Amplitude of spin-echo signal of product (A) and amplitude of standard sample (A_ssw) are measured and softening temperature is then calculated from the following relationship: T_s= K₁exp(K₂A/A_ss) where K₁ and K₂ are coefficients depending on the type of heavy petroleum product and on temperature of product in transmitter. EFFECT: reduced analysis time and increased measurement accuracy. 1 dwg, 1 tbl