NOVELTY - The system has an initial separating device (50) for separating mixture product to create a gaseous product stream and a solid product stream (70). A particle filtration unit (110) filters the gaseous stream and a coarse particulate fluxing agent to retain residual particles of char to create another solid product stream, while allowing passage of the gaseous product stream. Piping conducts the solid streams with terminus at a gasification reactor (10) for allowing entry into the reactor of a mixture product with the solid product streams and a coarse particulate conditioning agent.    USE - Gasification system i.e. two-stage slurry-feed lock-hopper type gasification system, for providing fixed-bed gasification, fluidized-bed gasification and suspension/entrainment gasification of solid or liquid carbonaceous feedstock for producing synthesis gas used for producing chemicals e.g. hydrogen, methanol, ammonia, substitute natural gas and synthetic transportation oil, and for power generation application. Can also be used for a single-stage slurry-feed gasification system and a single-stage/two-stage dry-feed gasification system.    ADVANTAGE - The system increases operational efficiency of a particle filtration system by preventing infiltration of char particles too deeply into the pores of filter elements so as to reduce differential pressure across the filter elements, thus extending filter element lifespan. The system adds conditioning agent to the raw synthesis gas upstream from the particle filtration unit, so that the conditioning agent allows rapid turn around of the filtration unit following filter element replacement, facilitates the removal of filter cake from the particle filters, and combines with removed filter cake for recycling of the gasifier and addition of fluxing agent via route, while eliminating need to premix fluxing agent with the carbonaceous feedstock to improve efficiency and rate of feedstock addition to the gasification reactor. The system connects unfired reactor upper section directly to top of fired reactor lower section, so that hot reaction products are conveyed directly from the reactor lower section to the reactor upper section, thus minimizing heat loss in the gaseous reaction products and entrained solids.    DETAILED DESCRIPTION - The mixture product comprises synthesis gas and char. The gaseous product stream exiting from separating device comprises hydrogen, carbon monoxide, a small amount of methane, hydrogen sulfide, ammonia, nitrogen and carbon dioxide. The coarse particulate fluxing agent comprises limestone, magnesium oxide, clay, silicates, horates, flyash and slag. The initial separating device is a particle removal cyclone. The particle filtration unit is a candle filter or a bag filter.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of a two-stage slurry-feed lock-hopper type gasification system.    Gasification reactor (10)    Taphole (20)    Initial separating device (50)    Dispersion devices (60, 60a)    Solid product stream (70)    Feeding devices (80, 80a)    Heat recovery device (90)    Particle filtration unit (110)