Implementation of Indonesia coal downstream policy in the trend of fossil energy transition

The implementation of downstream coal policies in Indonesia is regulated in Law Number 3 of 2020 to optimize coal’s domestic use and value-added. The policy is also supported by the issuance of fiscal, non-fiscal, and regional incentives. In Law Number 3 of 2020, the government of Indonesia states six types of coal downstream: coal upgrading; coal briquetting; cokes making; coal liquefaction; coal gasification; and coal slurry, yet the government has not defined which downstream coal products should be prioritized. Several parameters must be considered in implementing the downstream coal policy, those are the availability of coal and its characteristics, proven technology, economic and environmental feasibility. This study examines the mineral and coal sector regulation, taxation, coal resources and reserves, technology, and economics. In addition, to implement the commitment of reducing CO2 emissions, this study also considers applying Carbon Capture and Storage (CCS) or Carbon Capture, Utilization, and Storage (CCUS) technology to implement downstream coal policy.

Combined Treatments of Underground Coal Slurry: Laboratory Testing and Field Application

During the coal mining process, underground water is generated from the longwall face. In the meantime, the coal cutting process would produce coal particles. Coal slurry is generated in the underground working site, especially for water abundant coal mines. The generated coal slurry is treated to prevent water pollution. Due to the extensively existing of the suspended solid, the traditional process method would often introduce new problems. In this study, laboratory testing was conducted to investigate the characteristics, including the particle size distribution of the coal sludge, coal slurry compositions, slurry viscosity and coal mine water quality. In order to improve the coal slurry treatment efficiency, based on the laboratory results, a novel combined treatment of underground coal slurry is proposed. First, the coarse grained coal slurry is process by a vibrating screening machine. Then, the coal slurry containing fine coal powders is processed through a settling pond. The sedimentation results of the coal solid materials are analyzed. The polymer flocculant is also added into the coal slurry to improve the sedimentation. These combined treats of the coal slurry significantly remove the suspended solid and improve the quality of the coal mine water. Based on the laboratory testing, the specific details of the field applications are designed. The key novelty of this paper is the underground background. All of these treatments are based on the underground environment and are capable of being applied in underground workings. From field applications and observations, these novel combined treatments of coal slurry in the underground site are effective. This study provides a novel method to treat the coal slurry, which has innovations from engineering aspect. These procedures are useful for the underground coal slurry treatment, especially for water-abundant coal mines. The normal coal production is guaranteed and less affected by the coal slurry discharge process. Meanwhile, the water pollution problem is much addressed and the damage of coal slurry to the environment is reduced.

Improvement of sustainability and efficiency of urban heating using coal-water slurry fuel

Coal-water slurry fuel is coming into use in heat generation facilities as an alternative to natural gas and heavy oil. The main advantage of coal slurry is its cost efficiency. Our project is devoted to improvement of heat generation using coal-water slurry fuel instead of investing in new construction of coal-burning boiler houses. As an example, we considered implementing this project in the city of Leninsk-Kuznetsky, Russia. The project implies partial burning of coal slurry along with conventional coal burning. This solution is cost efficient and environmentally friendly yet not requiring major heat generation equipment replacement or renovation. The total cost efficiency of the suggested project is estimated at least as 1.1 billion rubles per year.

Effects of oxidation of SiC aggregates on the sintering behaviour and microstructures of SiC-CaAl12O19 composite refractories

In order to develop chrome-free refractory materials applicable in coal slurry gasification, SiC-CaAl12O19 (SiC-CA6) composite refractories were developed and prepared by using SiC aggregates and CA6 powders as main raw materials. The sintering behaviour of the composites was investigated. After firing at different temperatures under CO atmosphere, the effects of oxidation of SiC aggregates on the sintering behaviour and microstructures of SiC-CA6 composite refractorieswere investigated. SiC-CA6 composites could not be sintered when firing temperature was lower than 1500?C. SiC had a passive oxidation and the oxidation components were able to react with CA6 to form CaAl2Si2O8. The CaAl2Si2O8 melted into liquid when sintering temperature was in the range of 1500-1600?C, which promoted the sintering process of the SiC-CA6 composites. At temperatures above 1600 ?C, an active oxidation of SiC occurred. Simultaneously, SiC could also reacted with the SiO2(s,l) to form SiO, leading to the precipitation of Al2O3 and CaO in the liquid to generate plate-like CA6. Above this temperature, the sintering of the SiC-CA6 composite refractories was affected by the growth of CA6 and oxidation of SiC. This work demonstrates that the optimal sintering temperature for the SiC-CA6 composite refractories was 1600?C.

Static and Seismic Performance of Buried Pipelines: A review

Today, buried pipes can be considered one of the main substantial infrastructures which has significant role with human life. Such projects serve purposes, including, drain lines, water mains, sewage lines, telephone and electrical conduits, highway and railway culverts, gas and liquid-petroleum lines, coal slurry lines, subway tunnels and various other special functions. This paper focuses on reviewing, describing and understanding the static and dynamic behavior of underground pipes during earthquake events and at rest condition involving seismic vulnerability causes, failure modes of pipelines and loads subjected on pipes. A quick glance on the assisting factors that reduce the pipes breakage due to earthquakes is presented. Also, this paper reviews some previous studies about performance of underground pipes under seismic loads. It was concluded that the soil density has a significant impact on the displacements corresponding to the maximum force. For shallow pipes to obtain the minimum lateral displacement value, it is recommended to use soil density medium to dense state. It was observed also there is a relationship between the spacing of pipes and its displacement so; to obtain the minimum displacement the spacing between the pipes must be at least equal to the pipe diameter.

Study of slurry dewatering in a horizontally placed shell filtering construction

Dewatering of water-coal slurry or thickened product under conditions of operating SUEK-Kuzbass JSC enrichment plants is a promising direction of obtaining technogenic mineral resources. It should also be noted that the quality of the obtained product will be directly influenced by the quality of the initial raw materials. If the content of carbon particles is high and the average ash content of the solid phase is low, such a slurry will be of interest in terms of obtaining additional volumes of coal after dewatering. The object of this study is water-coal slurry obtained at the outlet of the radial thickener (thickened product). The subject of the research is technology of thickened product dewatering with the use of shell filter constructions. The aim of the work is to develop and substantiate parameters of low-cost technology of thickened product dewatering to ensure an increase in economic and environmental efficiency of mining operations. The idea of the work is to use the laws of mass transfer of suspended particles of water-coal slurry by filtering through specially made shell filter constructions (SFC).