Abstract Coal is the main source of energy in China and contributes to the national economy. However, unsustainable use of coal is accompanied by environmental problems. Coal preparation is the most economical and effective method for efficient cleaning and utilization of coal. This paper aims at resolving the difficulty of upgrading the clay-based thermal coal in China. For resolving the sieve and shallow tank sorting, a retreating sieve 6/3 mm dry depth screening along with the classification of heavy-medium washing process was proposed. In the industrial practice of Lijiahaohao mine of Shenhua Baotou mining industry (China), a multi-parameter control method (based upon location, flow rate and feed quantity) is put forward for the separation of heavy-medium and heavy-medium in shallow tank. When the relative height of the feeding position was 70% and the flow rate was 75%, the coal separation was the best. The high separation efficiency of 100-3 mm wide grain grade coal has also been realized. The yield of clear coal was 83.72%, and the value of E was 0.055 g/cm3. Lastly, the first thermal coal sieving and shallow tank 3 mm flip flow screen technology for heavy media separation system has been proposed in this work.