Speaking as someone who used to be a chemist, quicklime is apparently useful for hiding the odour of decomposition, as it reacts with and neutralises some of the smellier compounds produced by putrefaction, but useless for destroying evidence. It doesn't render or reduce flesh in any way, beyond mummifying it. For that, you'd need something much more corrosive, such as concentrated sulphuric acid, or TCA (steer away from HF as that stuff is just nasty, and produced and used industrially in such niche applications as to be quite probably easily traceable), and then you'd want to sieve the remains, which themselves would be highly corrosive and probably smelly gunk, for bits that don't easily dissolve, such as teeth, gallstones, fillings, medical implants, fragments of synthetic fibres, and so on.
Of course, my primary advice would be to not kill people in the first place. Apart from the obvious "murder is bad", which should go without saying, forensics are surprisingly good these days, and you will probably eventually get found out.
Biting the hand that feeds IT
