Study on coal recovery technology from waste fine Chinese coals by a vegetable oil agglomeration process

Abstract

Nowadays, coal production increases continuously due to an increase in mechanization in coal mining and demand in its related fields of application worldwide. Coal production in China is especially an increasing trend and a large amount of waste fine coal is produced. Waste fine coals usually contain large amounts of ash and inorganic sulfur due to non-selective coal mining of the coal. Therefore, waste fine coals are available as a resource and cause spontaneous combustion leading in turn to air pollution because of their coal contents and small particle sizes which increases the surface area liable to be wet and oxidized, and the disposal site of waste fine coals cause land occupation, soil pollution and water contamination.In this study, a vegetable oil agglomeration process was performed for coal recovery from Chongqing Nantong waste fine coals in China. The oil agglomeration process has been used to mineral oil of exhaustible resource. Therefore, in this study, several kinds of vegetable oils are selected as oil agglutinative agents because the vegetable oils which are renewable, available and less-pollutant energy resources. The effects of the parameters including particle sizes, agitation conditions, chemical structure and viscosity of vegetable oils were investigated based on the combustible matter recovery, ash reduction and efficiency index. It was concluded that particle sizes of waste fine coal, agitation rate and agitation time will influence on the recovery efficiency of combustible matter from its original waste coal by the colza oil agglomeration. Furthermore, a wide range of vegetable oil alteration grades including prepared waste vegetable oil samples and therefore, of oil properties, such as chemical structural changes and unsaturated carbonaceous functional groups by the oxidation processes in the used waste vegetable oils have to be achieved.

Research into the process of preparation of Ukrainian coal by the oil aggregation method

“…We shall note that the range of original pulp densities in the conducted experiments, ρ ws =50-600 g/cm 3 , is considerably wider than that in articles [9,[11][12][13][14]. At the same time, lower limits of ρ ws are close (we have 5 %, in [9] -7.5 %, in [11] -11.1 %).…”

“…This factor, according to studies [4,9,[11][12][13][14], is one of the most significant for obtaining quality concentrate and the waste of oiled aggregation of coal. This is confirmed by the results obtained in research.…”

“…During oil agglomeration of finely dispersed Chinese coal, vegetable oil was used as a binder [9]. Dimensionality of the original coal: -75; 75-150; 150-212; 212-300 µm.…”

“…The largest index of process efficiency was registered on minute 15 and it little changed subsequently. An important and positive feature of study [9] is the infrared spectroscopy of the binder -vegetable oil, which made it possible to identify functional groups, which provide the possibility to characterize structure of the reagent. The resulting empirical material is very valuable.…”

Recovery of combustible matter from waste fine Chinese coals by a waste vegetable oil agglomerating process and its combustion characteristics

“…However, the vegetable oils have been selected as oil agglutinative agents in our previous study [5] because the vegetable oils which are renewable, available and less-polluting energy resources. Furthermore, in this In this study, waste vegetable oil is used as the agglutinative agents instead of fresh vegetable oil and kerosene etc.…”