1. A feed slurry containing BaSO4, H2SO4 and water is washed with a dilute solution of H2SO4.
The washing takes place in a washer/settler tank such that the washed BaSO4 slurry has
𝐷
𝑤𝐵𝑎𝑆𝑂 4
= 0.48. (mass percent of solid BaSO4 of stream D). A sketch of the wash system is shown
on the figure below.
a. Obtain the DOF for the process. (10 marks)
b. Make a mass balance for the system to determine the effect of flow of wash solution (FB)
𝐷/𝐿
on the mass fraction of H2SO4 in the washed BaSO4 (𝑤𝐻2 𝑆𝑂4 ). (20 marks)
c. Discuss how does mass fraction of H2SO4 in the washed BaSO4 change with changing FB.
(5 marks)
The values for wBaSO4 refer to mass fraction of the solid (BaSO4) in the stream, while w#/L refers
to mass fraction in the liquid portion of the # stream. For example 𝑤𝐻𝐷/𝐿 2 𝑆𝑂4
refers to the mass
fraction of H2SO4 in liquid phase (L) in stream C.
The washing takes place in a washer/settler tank such that the washed BaSO4 slurry has
𝐷
𝑤𝐵𝑎𝑆𝑂 4
= 0.48. (mass percent of solid BaSO4 of stream D). A sketch of the wash system is shown
on the figure below.
a. Obtain the DOF for the process. (10 marks)
b. Make a mass balance for the system to determine the effect of flow of wash solution (FB)
𝐷/𝐿
on the mass fraction of H2SO4 in the washed BaSO4 (𝑤𝐻2 𝑆𝑂4 ). (20 marks)
c. Discuss how does mass fraction of H2SO4 in the washed BaSO4 change with changing FB.
(5 marks)
The values for wBaSO4 refer to mass fraction of the solid (BaSO4) in the stream, while w#/L refers
to mass fraction in the liquid portion of the # stream. For example 𝑤𝐻𝐷/𝐿 2 𝑆𝑂4
refers to the mass
fraction of H2SO4 in liquid phase (L) in stream C.
