A waste treatment device may include a solid-liquid separator which is configured to receive and separate waste into solids and liquid. The waste treatment device may further include a solids treatment arrangement which is configured to receive the solids from the solid-liquid separator, wherein the solids treatment arrangement comprises a disinfection unit having a heating mechanism configured to heat, without burning, the solids so as to disinfect the solids to convert the solids into pathogen-free-treated-solids. The waste treatment device may further include a liquid treatment arrangement which is configured to receive the liquid from the solid-liquid separator and to treat the liquid so as to convert the liquid into pathogen-free-effluent. The solid-liquid separator may include a curved-funnel-shaped inner separator surface and a frustoconically-shaped inner liquid guide surface whereby the respective narrower ends are directed towards each other.