A process for producing a H 2 -containing product gas and for producing purified water from a raw water stream containing contaminants, the process comprising: (i) withdrawing a reformate comprising H 2, CO, CH 4, and H 2 O from a reformer furnace; (ii) passing at least a portion of the reformate from step (i) to a first evaporator of a plurality of evaporators of a thermal water purification system; (iii) passing at least a portion of the raw water stream to the first evaporator; (iv) introducing a first steam stream into the first evaporator, wherein the first steam stream is formed in a second evaporator of the plurality of evaporators of the thermal water purification system by heating the at least a portion or a second portion of the raw water stream by indirect heat transfer with the at least a portion or a second portion of the reformate; (v) heating the at least a portion of the raw water stream passed to the first evaporator in step (iii) in the first evaporator by indirect heat transfer with the at least a portion of the reformate from step (ii) and separately by indirect heat transfer with the first steam stream from step (iv) to form a second steam stream by evaporating a portion of the at least a portion of the raw water stream, thereby cooling the at least a portion of the reformate, forming a first condensate stream from the first steam stream, and concentrating the contaminants in the at least a portion of the raw water stream; (vi) withdrawing the second steam stream from the first evaporator; (vii) withdrawing the at least a portion of the reformate from the first evaporator; (viii) withdrawing the first condensate stream from the first evaporator, wherein the purified water comprises the first condensate stream; (ix) withdrawing the at least a portion of the raw water stream from the first evaporator, the at least a portion of the raw water stream having a higher concentration of the contaminants than when it was introduced into the first evaporator; and (x) passing the at least a portion of the reformate withdrawn in step (vii) to a gas separator and separating the at least a portion of the reformate in the gas separator to produce at least a portion of the H 2 -containing product gas stream and at least a portion of a by-product gas stream. (i) withdrawing a reformate comprising H 2, CO, CH 4, and H 2 O from a reformer furnace; (ii) passing at least a portion of the reformate from step (i) to a first evaporator of a plurality of evaporators of a thermal water purification system; (iii) passing at least a portion of the raw water stream to the first evaporator; (iv) introducing a first steam stream into the first evaporator, wherein the first steam stream is formed in a second evaporator of the plurality of evaporators of the thermal water purification system by heating the at least a portion or a second portion of the raw water stream by indirect heat transfer with the at least a portion or a second portion of the reformate; (v) heating the at least a portion of the raw water stream passed to the first evaporator in step (iii) in the first evaporator by indirect heat transfer with the at least a portion of the reformate from step (ii) and separately by indirect heat transfer with the first steam stream from step (iv) to form a second steam stream by evaporating a portion of the at least a portion of the raw water stream, thereby cooling the at least a portion of the reformate, forming a first condensate stream from the first steam stream, and concentrating the contaminants in the at least a portion of the raw water stream; (vi) withdrawing the second steam stream from the first evaporator; (vii) withdrawing the at least a portion of the reformate from the first evaporator; (viii) withdrawing the first condensate stream from the first evaporator, wherein the purified water comprises the first condensate stream; (ix) withdrawing the at least a portion of the raw water stream from the first evaporator, the at least a portion of the raw water stream having a higher concentration of the contaminants than when it was introduced into the first evaporator; and (x) passing the at least a portion of the reformate withdrawn in step (vii) to a gas separator and separating the at least a portion of the reformate in the gas separator to produce at least a portion of the H 2 -containing product gas stream and at least a portion of a by-product gas stream.