What is the purpose of triethanolamine in cement? Is it (triethanolamine) also in admixtures (water reducer, air entraining, superplasticizer, for example) for concrete? Could this chemical affect the final appearance of finished flatwork concrete? Could it cause uneven discolorations in the cured concrete?

Triethanolamine is used as a set controlling chemical in concrete admixtures. However, I am not aware of it causing differences in appearance of the surface of finished concrete. That phenomenon sounds more like effluorescence.