Comparison And Economic Analysis Of Coal Tar Hydrogenation Technology

The characteristics of our country's energy resources determine that for a long period of time in the future,coal is still the main form of our country's energy consumption structure and the main driving force for the development of our national economy.If coal cannot be used cleanly,it will directly lead to the increase of SO2,CO2 and other waste gases,and at the same time increase the content of suspended particles.In the clean and efficient utilization route of coal,coal pyrolysis is the leader and coal tar hydrogenation is the key.Coal tar is very similar to crude oil in composition and properties.Under certain conditions,catalytic hydrogenation can produce light fuel with high calorific value,good thermal stability and good combustion performance.After fractionation,components such as gasoline and diesel oil can be obtained,which not only improves the added value and utilization rate of products,but also alleviates the contradiction between supply and demand of petroleum in our country.It has important strategic significance.This paper compares and analyzes the existing coal tar cut fraction hydrogenation technology,delayed coking hydrogenation technology,suspension bed hydrogenation technology,full fraction hydrogenation technology and wide fraction hydrogenation technology from the aspects of process,liquid oil yield,hydrogen consumption,raw material adaptability,equipment investment,operating cost,catalyst,etc.The existing problems and development trend of coal tar hydrogenation technology were discussed.Using two coal tar processing schemes with high market acceptance,full fraction hydrogenation and delayed coking hydrogenation,the economy of coal tar hydrogenation was evaluated by sensitivity analysis method.This paper draws the following conclusions:(1)the main difference between various coal tar hydrogenation technologies lies in the pretreatment of raw coal tar before fixed bed hydrogenation.The research on the treatment of heavy components is the technical core of coal tar hydrogenation technology.Coal tar suspension bed hydrogenation technology has high product yield and good quality,but high investment and high operation cost;The raw material utilization rate of the whole fraction coal tar hydrogenation technology reaches 100 %,and the product oil yield is high,but the technology has not yet been popularized and applied,and there are technical barriers.Cutting fraction,delayed coking and wide fraction hydrogenation technology have all eliminated heavy components from coal tar,resulting in low oil yield.however,they have the advantages of long running period and wide adaptability of raw materials.Enterprises should determine the hydrogenation route and processing scale according to the quality of coal tar.(2)The investment intensity of the coal tar whole fraction hydrogenation scheme is lower than that of delayed coking hydrogenation,the operation cost is high,and the catalyst cost is high,but its energy utilization efficiency is high,and the product output value is high,showing good market economic benefits.Through sensitivity analysis,the product price has a great influence on the margin difference between the two schemes.(3)The development of coal tar hydrogenation technology is facing the problems that the catalyst is prone to coking,poisoning and deactivation,the source of raw materials is limited,the octane number of its product gasoline fraction is low,and the cetane number of diesel fraction is low,which cannot meet the requirements of the national standard fuel oil index in our country.According to the composition characteristics of coal tar,the coal tar hydrogenation industry chain can be extended to develop refined and high added value products downstream of coal tar hydrogenation.