According to the production demand by coking companies and based on the analytic hierarchy process and pairwise comparison method,coking coal quality evaluation system is established,including scoring criteria for the quality of coking coal.Objective assessment is also made for the coking coal being used by Anning Coking Branch of Yunnan Coal Energy Co.,Ltd..

The coking pilot test was carried out by using a 300 kg test oven to study the effect of coal moisture and bulk density on coke quality.The result shows that under the test conditions,the change of coal moisture has little effect on the quality of coke and appears tiny regularity.Only by increasing the bulk density of blend coal,M40 does not change much,however M10 and CSR are both improved obviously.When both moisture and bulk density are changed,some obvious relationship are found with the cold strength,hot strength and the particle size of coke.

The newly-built 6.78 m stamp-charge battery of Xintai Zhengda Co.,Ltd.is an ultra-high capacity coke oven that first adopts CPS system in the world.The practical experience shows that the CPS system can effectively solve the problems such as charging emission escaping,oven door emission leakage,etc.and ensure stable pressure at the bottom of coking chamber so as to extend the service life of coke oven battery.

China has classified fat coal (including gas-fat coal),primary coking coal (including 1/3 coking coal) and lean coal as “special and scarce coal”.The compatibility of different kinds of low-quality “special and scarce coal” is studied.By blending with appropriate amount of these coals,i.e.under the condition of the proportion of high-quality “special and scarce” coking coal and fat coal reduced down to 3%,and no coking coal with high metamorphic degree,high strength metallurgical coke can be produced.

The basic working principles for three technologies of oven pressure regulation are introduced in this paper,i.e. German PROven,Italian SOPRECO and Chinese CPS.Through analysis and comparison,the CPS enjoys more advantages in upgrading of individual regulation for oven pressure of the existing coke ovens,which is worth popularizing and applying.

In this study,three kinds of individual coking coals with different ranks were selected,i.e.gas coal,fat coal and main coking coal,which are carbonized into coke at the end of coking temperature 950 ℃.The pore structure parameters of coke were measured by micrograph analysis.The pyrolysis volatilization process of coking coal was measured by thermogravimetric analysis and the pyrolysis softening flow process of coking coal was measured by Gieseler plasticizer.The results show that the interaction between volatilization and softening flow of coking coal determines different microporous structures of the coke.

The cause of COG heating system explosion is analyzed in terms of process calculation.The result shows that avoidance of air entering the gas system is the fundamental way to prevent the gas pipeline in the coke oven cellar from explosion.Detailed preventive measures are also introduced, which can be used as reference for the coke oven cellar management.

In this paper，by analyzing several “time” concepts on charging and pushing，and by comparing the differences between coking time and cycle time，the charging timing can be defined.Based on the actual coke pushing schedule of a coking plant，the errors in pushing coefficient calculation and the causes are pointed out，correct calculation is demonstrated，which provides a scientific basis for assessment of production management. 

Nitric acid,as one kind of corrosion inhibitor,is an important accessory in the Takahax-Hirohax desulfurization process.But since late 2014,a continuous and noticeable increase of nitric acid consumption has appeared.In this article,the cause of this problem was found through the experiment and the theoretical analysis.Meanwhile,corresponding countermeasures were proposed.

High content of cyanides and sulfides in waste liquid produced with vacuum potassium carbonate desulfurization process would easily affect waste water treatment system in the process of production.The removal rate of cyanide and sulfide are 95% plus and 99% plus respectively after pretreatment of waste desulfurizer liquid by IPE-DCN process.The sludge from the pretreatment is used for coal blending for cokemaking,and the clear liquid after pretreatment could reduce the impact on the water treatment system.

According to the characteristics of coke oven flue gas and low temperature SCR process,a low temperature-plate type SCR DeNOx catalyst with high activity,strong sulfur resistance and water resistance,strong plugging resistance and alkali metal poisoning resistance has been developed.It shows excellent denitration performance at 150 ℃ in pilot-scale test.

In this paper,sulfur recovery technology by Claus process is introduced in aspects of development orientation,the chemical reaction mechanism in the furnace,the common process,liquid sulfur molding and Claus reaction catalysis,etc..Two cases in Handan Plant and Formosa Plant are compared with the application of the Claus system in two coking plants.

In view of the characteristics of wet desulphurization flue gas of coke oven,four kinds of technique routes of coke oven flue gas plume removal are compared.The result shows that the flue gas condensation and reheating method is the best technical route,which can not only realize completely effect of wet plume elimination for coke oven flue gas,but also reduce the pollutant emissions for the flue gas.With the project of coke oven flue gas plume removal as research object and base on “Temperature-humidity curve and tangent diagram”,research is carried out for the influence of heat transfer temperature of MGGH heat exchanger and flue condenser on steam consumption and system operating cost.The study shows that the steam consumption and operating cost both decrease with the increase of temperature transfer of MGGH heat exchanger and flue condenser,in addition,the operating costs of the system is proportional to the steam consumption when at the same condition that white plume can be removed.

In this paper,the main composition of CDQ flue gas and measurements are introduced.Several typical desulfurization processes and formation products are described.Two common processes for flue gas desulfurization are analyzed,in which the independent desulfurization process for the bled gas is commonly used,easy in operatioin with low investment cost and the treated flue gas can meet the requirement of environmental emission standard.

If COD level in stripped water goes high,it would do no good to the stability of phenol-cyanide waste water treatment system.Analysis was made from overall process,with Coking Plant of Jiugang (Group) as an example.Measures were taken,such as coal blend ratio was optimized and free space temperature on oven roof was adjusted,which could eventually stabilize the COD level in the stripped water.Biological index were adjusted to the extent that the normal metabolism of micro-organism can stay away from influence and its effluent can remain stably acceptable.

The waste heat recovery system from ascension pipe for 6 m battery has been running safely and stably for more than three years in Masteel.During the actual operation,the material and structure of the heat exchanging tubes have been optimized and the problems such as water leakage at the ascension pipe and carbonization on the inner wall of the pipe,etc.have been solved,which bolstered experiences in the waste heat recovery from ascension pipe and achieved remarkable economic and environmental benefits.

Through optimization of thermal insulation for catalyst bin and dust bin, NH3 supply system and pneumatic dust conveying system, the bagfilter resistance can be maintained below 1.2 kPa.It can ensure the suction volume of the ID fan for DeSOx and DeNOx so that proper suction for normal coke oven heating can be maintained and stable operation can be ensured for the whole DeSOx and DeNOx unit for coke oven flue gas treatment.

The application of spiral type waste heat recovery system from ascension pipe is introduced,including its main process parameters.The advantages of this system are described.Suggestions for improvement to the problems in using this system in the Coking Plant of Liuzhou Iron & Steel are proposed.