A system and a method are provided for melting solid sulfur and maintaining the resulting molten sulfur in liquid state. The system and the method may be fabricated, installed and operated at low capital costs, with high throughput rates at high operating efficiencies and low maintenance costs. Specific embodiments of the invention include modular and non-modular designs, which may be installed and operated with low to high degrees of automation, allowing the user to tailor the final configuration to meet specific requirements. The system of the invention comprises a specific configuration of a prescribed solid sulfur feed unit, a prescribed high-capacity melting unit, a compartmentalized pump tank assembly, and a heat exchanger located outside the high-capacity melting unit. The method provided follows the configuration of the system.