Research On Key Technical Issues In Installation And Commissioning Of Potassium Dihydrogen Phosphate Production Unit

Potassium dihydrogen phosphate can not only be used as high efficient compound phosphorus and potassium fertilizer for almost all crops in agriculture but also as some necessary cultivation agents,strengthening agents,leavening agents,and fermentation assistants or raw materials etc in modern medicine,chemical industry and food industry.Therefore,the research and exploitation of the preparation technique of potassium dihydrogen phosphate,and the construction of the production plant of potassium dihydrogen phosphate with lower consumption and higher efficiency are of considerable significance to the development of efficient agriculture and the application expansion of potassium dihydrogen phosphate.However,the production technique of potassium dihydrogen phosphate is complex,and its equipment is numerous.The key technical problems of the installation and debugging of potassium dihydrogen phosphate production equipment were focused in this thesis,which is of great significance and practical value for the safe and stable operation of potassium dihydrogen phosphate production equipment.The production equipment of 30kt/a potassium dihydrogen phosphate for agricultural use at Hong Lin Branch of Yunnan Yuntianhua Co.,Ltd.was researched as an object in this thesis.In allusion to the key technical problems and failures that occurred in the production process of the potassium dihydrogen phosphate production equipment,the relatively systematical analyses and the technical reforms were carried out.The rectification measures were proposed after the repeated operation and debugging of the production equipment,and the trial production verification was conducted for several times after the rectification.The main research contents and achievements are as follows:1.In allusion to the key problem of potassium dihydrogen phosphate equipment during the trial production,or difficult to control the crystallization of potassium dihydrogen phosphate,based on crystallization theory of potassium dihydrogen phosphate crystallization,the influence of the operating conditions of the crystallizer on the crystallization was analyzed,and the best operation condition of the crystallizer was obtained through the combination of the actual production instance.As for this production equipment,the combination of the best operation condition of the crystallizer of potassium dihydrogen phosphate was that,while the operation temperatures of the crystallizer were respectively 36?38°C in summer and 33?35°C in winter,its operation was stable and easy to be controlled;the circulation flux change of the crystallizer was an important means to adjust the crystallization output and granule magnitude of potassium dihydrogen phosphate,the normal production in this equipment was suitable with the whole opening of 3 circulation pumps about the working frequency of 75%.2.In allusion to the key two problems of potassium dihydrogen phosphate equipment,or the centrifuge removal rate was lower,and the crystal materials blocked the system of equipment and pipeline during the separation of potassium dihydrogen phosphate,the two measurements were taken.The first one is that,the selection of filter cloth type of the horizontal centrifuge and the optimization of operating parameters of the centrifuge were adjusted,and the removal rates of the centrifuge under different operating states in the crystallizer were ensured from the incipient of 36?49% to the middle and late 72?83%.The second one is that,the inlet pipeline of the centrifuge,the feed port,the cloth dispenser,and the washing water of the press cloth were analyzed to propose the modification scheme,the problems to block the centrifuge and the pipeline with the crystal materials were solved,and the average failure frequency of the centrifuge was declined from more than 10 times every day to 1 time 10 days.3.In allusion to the problem that the production environment was severely affected by the presence of free ammonia in the concentrated crystallization system of ammonium chloride,through measuring,analyzing,calculating,and adding ammonia scrubbing recovery devices,the ammonia waste was eliminated,the safety and environmental risks were reduced.Moreover,the optimization scheme of the ammonium chloride concentration crystallization process system was proposed and proved to be feasible in the trial production.The advantages and disadvantages of the scheme were also analyzed and optimized,and a breakthrough for the further implementation of energy-saving and consumption reduction in the production equipment in the future was found.4.In allusion to the other non-key problems in the trial production of potassium dihydrogen phosphate production equipment,the four effective corrective measurements were taken.The first one is that,according to the physical property of wet phosphorus and potash fertilizer,the belt feeder was used to replace the double screw feeder as the feeding device of the drying system,so as to solve the bottleneck problem of the drying system.The second is that,the packaging environment of phosphorus and potassium fertilizer was improved by increasing the packaging machine with the use of the original dust removal exhaust fan.The third one is that,based on the requirement of product granularity of potassium dihydrogen phosphate,the caking materials that affected the product quality and the operation of the packaging system were screened out by increasing the screening equipment in the finished product packaging system.The fourth one is that,the safety of the circulating water system was ensured and the purpose of saving water was achieved by replenishing the seal water collected by the pump to the extraction washing water.In this thesis the key and general problems that existed in the trial production of potassium dihydrogen phosphate production equipment were researched,and the corresponding rectification measurements were implemented and verified repeatedly on the equipment.Thereout the process parameters or process routes of potassium dihydrogen phosphate production equipment were adjusted and optimized.These works enabled the continuous,stable,and efficient operation of the production equipment of 30kt/a potassium dihydrogen phosphate for agricultural use at Hong Lin Branch of Yunnan Yuntianhua Co.,Ltd.,and finally the long-term stable operation of the production equipment of potassium dihydrogen phosphate was realized.In this way it can not only accumulate certain experiences for the operation optimization of the production equipment of potassium dihydrogen phosphate with organic extraction method,but also makes the enterprise better economic benefit,moreover can provide some technical measurements for the further optimization of the production equipment of potassium dihydrogen phosphate with the organic extraction method in the future.