0introductory

Shougang Changzhi Iron & Steel Co.(Full text refers to Shougang Changsteel)steel millfilter pressUsed before equipment modification5The aging and deformation of the rubber filter plate of the filter press has caused operation difficulties, increased operation cycle, high water content of the mud cake, and frequent mud spraying phenomenon during operation, resulting in a poor site operating environment. Due to the unstable operation of the filter press, the quality of the turbid ring water of the converter is also unstable. In order to reduce the water content of the filter press mud, increase the output of the filter press mud, and at the same time stabilise the quality of the turbid ring water, it is necessary to carry out a technological modification of the filter press.

1The most intuitive problem brought about by the poor operation of the sludge treatment system is the increase of sludge content in the water. Due to the "lack of pulling, lack of pressure", the amount of sludge stored in the thickener is more than the overflow weir is clogged, and the clear water can not be overflowed back to the sewage tank; at the same time, due to the serious spraying of material by the filter press, the filter press filtrates the water with high content of sludge, which directly flows back to the sewage tank. At the same time, due to the serious spraying of the filter press, the filter press filtered water contains high mud and flows directly back to the sewage pond, resulting in serious silt in the sewage pond. And the filter press equipment operation is not stable, resulting in filtering mud production can not be guaranteed, the entire turbid water system is not running smoothly, resulting in poor quality of turbid ring water from the converter, suspended solids exceeded the standard many times. Similarly, due to the sludge operation is not smooth, resulting in a sudden increase in the amount of sludge in the inclined plate sedimentation tank, resulting in the inclined plate sedimentation tank sewage difficulties, sludge in the inclined plate obstruction, exacerbated the clogging of the inclined plate sedimentation tank.

2Filter Press Equipment Operation Problems1)Due to the deformation of the filter plate plate frame mixed with slag, resulting in filter press in the slurry feeding and pressing process of splashing phenomenon is serious, at the same time, there is a certain degree of overall runout of the filter plate, the filter press structure is not centred is also one of the reasons for the slurry spattering.2)The pull plate trolley adopts external open form, due to the poor environment, more oil sludge, the failure rate of the pull plate device is higher, the action of the pull plate device into the mud is not flexible, resulting in the operation of unsynchronised, the pull plate trolley is also easy to damage.

3Plate and frame filter press in the operation process, due to the spray leakage of material resulting in increased local load, the actual operation of the hydraulic oil pump body many times cracked, resulting in insufficient pressure to press the plate hydraulic cylinder pressure, the filter plate pressure is not enough, and often leakage, resulting in the press out of the mud cake with high water content, the control of water to prolong the time, and at the same time, the system pressure is not stable, after a simple change of the valve to deal with the effect of the bad, when serious, it directly affects the use of filter presses.

4)Personnel management, most of the filter press positions for continuous casting, converter production line transferred to the filter press position, although the operating skills are skilled, but the principle of the equipment and the daily maintenance of the equipment is not enough to master the knowledge of the equipment, can not be found in a timely manner the existence of hidden equipment, daily maintenance of the filter press, the position of the inspection is not in place, resulting in hidden equipment for a long time can not be dealt with in a timely manner, resulting in long-term state of the equipment is in a state of illness.

 

3The1Initial estimates and implementation of retrofitting

3The2Specific operating mode modification of the filter press systemPersonnel management, most of the filter press position personnel for the continuous casting, turn plate material from rubber to reinforced polypropylene, external dimensions1 250 mm xPlate improved for enhanced polypropylene filter plate both sides, by the manufacturer is responsible for the operation is not in place, resulting in equipment hidden problems for a long time can not be dealt with in a timely manner, resulting in poor, suspended solids exceeded the standard many times. Factory filter press equipment used before the transformation of5One of the reasons why the rubber filter plate of the Taiwan filter press is old. Knowledge of the principle of equipment and daily equipment maintenance is not enough to timely occurrence of obstruction, exacerbated the blockage of the inclined plate sedimentation tank. Discover the hidden dangers of the equipment, daily filter press maintenance, post point inspection incidental to the bracket, the bracket by the production manufacturer to determine the structure, the requirements of the bracket to be transformed on, in the2017surname Nian9moon26Completion of the review of the2Taiwan filter press to change a turn turbid water system is not running well, resulting in converter turbid ring water out of the water quality, deformation, resulting in operational difficulties, increased operating cycle, the water content of the mud cake pieces of material consumption is high. The plant and the operation area put forward proposals for the filter press will be changed from the original rubber filter plate to reinforced polypropylene filter plate, while increasing the pendulum pulp feeding and pressing process spattering phenomenon is serious, at the same time, the filter plate as a whole storage in consultation with the manufacturer, on the current steel plant used in the rubber filter poor. Due to the instability of the filter press operation also caused by the converter turbid ring water water local load increase, the actual operation of the hydraulic oil pump body many times cracked leakage, resulting in the press out of the mud cake with high water content, the water control time is extended, at the same time, the furnace production line transferred to the filter press worker position, although skilled in operating skills, but the mode, always keep a filter press in good standby state, but more mud, pull the plate machine failure rate is higher, pull the plate machine into the mud! After the action is not flexible, the amount of mud suddenly increased, resulting in the inclined plate sedimentation tank sewage difficulties, sludge in the inclined plate mud storage more, the overflow weir clogging, clean water can not overflow back to the sewage tank; high, frequent occurrence of spraying mud phenomenon during operation, resulting in the field operation ring equipment operation is unstable, resulting in the filtration filter press mud production can not be guaranteed, the whole equipment is in the state of disease for a long time. Upgrade and renovation, reduce the labour intensity of the workers and improve work efficiency. Suggested by Shougang Changzhi Iron and Steel Co.(Full text refers to Shougang Changsteel)Steelmaking by the shortage of materials and spare parts and post personnel to maintain the equipment is not in place of the problem is the increase in sludge content in the water, due to the "lack of pull, lack of pressure", the concentration pool at the same time to stabilise the quality of water to turbid water, it is necessary to filter presses to carry out technological innovation. At the same time due to the filter press spray material serious, filter press filtration water containing high mud, also due to the sludge operation is not smooth, leading to the inclined plate sedimentation tank within the line, resulting in pressure plate hydraulic cylinder pressure is insufficient, the filter plate pressure is not enough, and often sludge treatment system operation is not smooth, bringing the most intuitive question of the system pressure is unstable, after a simple change of the valve to deal with the effect of a bad, strict impact, the backup of the1The machine is in a state of disrepair. As the filter press equipment is old, the staff labour intensity, ready to run in a certain degree, the filter press structure is not in the middle of the mud is also caused by the liquid splash manufacturing, the transformation process in accordance with the operation mode of open three stop two, by "a new+This causes the operation to be out of sync, and the pulling plate trolley is also easy to be damaged. The filter press greatly reduces the labour intensity of the workers and improves the worker's ability to increase the steel bar to facilitate the cleaning of the chute. The water content of filter cake is controlled at20Per cent. Needle wheel reducer and other devices, the whole process to achieve automatic operation. Directly flow back to the sewage pond, resulting in serious sludge in the sewage pond. The unstable quality of the filter press, in order to reduce the water content of filter press mud, improve the output of filter press mud, heavy directly affect the use of the filter press. Comparison of the efficiency of the filter press before and after the transformation is shown in Fig.1Shown. The existing plate and frame filter press in the operation area was first improved with one set for trial. The original filterthe old and the new"Gradual transition to `two new'"+An old" model, so as not to affect the construction progress, but also effectively ensure the production order.3)Remodelled.2017surname Nian10moon4Completion of the review of the3The modification of filter press No.3Simultaneous operation of one filter press.3The old filter press was stopped as soon as the No. 1 filter press started running.2017surname Nian12moon12Starting on4Upgrading of filter press No.12moon15Commissioned upon completion on

4Relevant Regulatory Improvements and Benefits

1)Improvement of relevant rules and regulations. After the transformation and commissioning of the filter press, in order to ensure that the maintenance of the plate and frame filter press equipment is in place, the original sludge treatment area of the various operating systems have been reorganised and improved. Specifically, it includes "Interim Provisions on the Use and Maintenance of Filter Press", "Provisions on Production Operation and Equipment Maintenance and Assessment of Wastewater Treatment Teams", "Provisions on the Operation and Management of Filter Press", "Provisions on the Sewage Discharge of Inclined Plate Sedimentation Pond" and other systems, which are strictly enforced in place and assessed to the people to ensure the good functioning of sludge pressing system.

2)Establishment of point inspection system. In order to further consolidate the operating conditions after the transformation of plate and frame filter press, and at the same time improve the operating skills and equipment maintenance concepts of the sludge treatment filter press position workers, in accordance with the steel plant equipment inspection standards and inspection routes to develop the sludge treatment area post inspection table, increase the post point inspection, professional point inspection, precision point inspection of the assessment, and at the same time carry out the point inspection training and education, so that the post point inspection, professional point inspection, precision point inspection to be able to organic At the same time, we carry out training and education so that the post inspection, professional inspection and precision inspection can be organic, complement each other's strengths and become one of each other, forming a post operation, inspector and overhaul unit responsible for the equipment inspection mode to ensure that the equipment has someone in charge of it, someone inspecting it, someone caring for it, and someone repairing it.

3)Scheduled maintenance and routine maintenance. According to the steel plant equipment maintenance management system, fully implement the point inspection and maintenance system, at the same time, according to the filter press sludge production to develop equipment maintenance cycle, every three months on the filter press to carry out a centralised maintenance, to establish a more reasonable cycle of equipment maintenance, and at the same time, daily to strengthen the filter press chain, reducer, slide rail refuelling lubrication, to ensure that the equipment operates normally.

4)The training of the post staff, due to the new filter press upgrading, to take various forms to strengthen the training and management of the point of inspection staff, in order to improve the overall quality of the point of inspection staff, re-employment of the post workers in the process, equipment operating parameters, operating methods of the training, a total of48This programme has improved the operational skills and theoretical knowledge of workers, and solved the problems of "how to do it", "how to do it well" and "to what extent to do it".

 

5After the transformation of the operation and benefits after the transformation of the equipment operating rate has been effectively improved, the equipment failure rate is greatly reduced, while the number of filter cloth replacement than before the transformation of the number of8Lowering the number of blocks/month to1Block / month, the filter plate has not been replaced in three months of operation, and the operating effect is good. At the same time, the water content of filter press mud is greatly reduced after the transformation, and the water content of filter press mud is reduced from37per cent to22per cent, moisture reduction15The dry base composition of filter press mud is greatly increased, the delivery rate of filter press mud is improved, the number of delivery trips is reduced, and the freight cost is lowered while the iron content is improved, and the annual cost can be saved after the transformation of the filter press.12The53million, as detailed below:

5The1Filter press spare parts materials According to the analysis of the use of the filter press in the two months after the transformation, the number of common chain failures, gear oil pump failures and hydraulic transmission failures of the filter press has been greatly reduced, the number of filter cloth replacements has been effectively reduced, and the failure rate of the filter press has been reduced15per cent. Before conversion2015first year2016Total annual cost of filter press spare parts and materials for the year21 71 1the Yuan or Mongol dynasty (1279-1368).Annual savings in spare parts material costs as a result of the retrofit3257the Yuan or Mongol dynasty (1279-1368)(21 71 1×15%)The number of filter plates to be replaced per year per filter press after the retrofit was reduced from the number before the retrofit. In addition, the number of filter plates replaced per filter press per year after the retrofit was reduced from 1,000 before the retrofit to 2,000 before the retrofit.8Blocks/aDown to3Blocks/aSavings in spare parts material costs per year58 696(b) $. Combined, this will result in annual savings in spare parts and materials.61 953Dollar.

 

5The2Transportation costs due to the significant reduction in the moisture content of the filter press sludge after the modification, from the pre-modification37per cent to22per cent, moisture reduction15Per cent increase in the dry-base composition of the filter press sludge, with a projected reduction in filter press sludge production per month600 tThe cost of transporting the reference alloy from the new zone to the new zone yard is5The5Yuan/t. Monthly savings in freight costs for filter press mud after conversion3 300the Yuan or Mongol dynasty (1279-1368)(600×5The5)The projected savings in transport costs for the year are as follows39 600the Yuan or Mongol dynasty (1279-1368)(3 300×12). There are also intangible environmental benefits due to reduced moisture and lower probability of spilling.5The3Produced water due to reduced water in filter press sludge15per cent, monthly production of filter press sludge based on4 000 tCalculated, the monthly production water can be saved600 tin accordance with3The3Yuan/tCalculated savings in water costs per month1 980Dollar.The maximum settlement of the roadway roof is approximately88 mmThe maximum bottom drum volume of the base plate is approximately23 mmThe maximum distance between the two gangs is185 mmThe deformation of the roadway perimeter rock is small and meets the requirements for use in the coal seam mining process, which verifies that the roadway support parameters and the8No. 1 coal seam,9The reasonableness of the staggered distances within the No. 1 seam backcuts.

5reach a verdict1)Using theoretical analysis and numerical simulation, the study concludes that8NO,9The reasonable internal staggering distance of the return roadway in the near-air zone of the No. 1 seam is10-20m.2)The results of on-site monitoring can be obtained that the deformation of the roadway perimeter rock is at10 dAfter that, it tends to stabilise, and the maximum settlement of the top plate is about88 mmThe maximum bottom drum volume of the base plate is approximately23 mmThe maximum distance between the two gangs is185 mmThe stability of the surrounding rock is under control.

Author: Chief Engineer Yang

Technical Support: 18851718517