Abstract: The coking plant of Liuzhou Iron & Steel Co.，Ltd optimizes the tar removal process of coal water, extends the coal water retention time, and brings the effect of tar removal by gravity into full play. Meanwhile，the numbers of coal water distributors are increased and the outlet of coal water is improved to reach tar removal efficiency up to 83.65%. After the optimization，the tar content in the coal water is significantly reduced so that blockage in ammonia stripping line and the ammonia stripper can be avoided，and adverse impact on the subsequent process can be minimized.

Key words: Coal water, Tar removal by gravity, Ceramic filtration, Optimization and modification