How to clean the coking and carbon deposits of heat transfer oil

After a long period of use, the thermal oil boiler diesel burner will produce a certain amount of carbon deposits on the inner furnace wall , Resulting in poor thermal conductivity of the boiler diesel burner or longer heating time, and poses a certain safety hazard. Therefore, after a period of use, you need to clean it to remove carbon deposits. The formation of carbon deposits of high-quality heat transfer oil will be slow, while the rate of carbon deposits of poor-quality oil will be very fast. The reason for the carbon deposition of the heat-conducting oil boiler diesel burner The heat-conducting oil boiler light oil burner is an organic heat carrier furnace. This kind of boiler diesel burner is also called a heat medium furnace, which is a heat source that relies on the heat transfer oil as an intermediary. It can heat up quickly, has strong stability, and has the characteristics of low pressure and high temperature! Heat conduction oil furnace light oil burners are generally used in the field of heating, the temperature is three or four hundred degrees, but thermal cracking occurs during use, and the pipeline will age for a long time, and carbon deposits will be generated inside the pipeline and equipment. It affects the heat transfer efficiency! The formation of coking and carbon deposits in the heat transfer oil will cause excessive pressure loss in the furnace tube, and when the coking is serious, the furnace tube will be blocked; the surface temperature of the furnace tube will rise. Because the thermal conductivity of the coking layer is much lower than that of steel, the thermal resistance of the coking area will increase. , The radial temperature gradient of the furnace tube becomes larger, in the place where the coking layer is thick, hot spots appear on the surface of the furnace tube, which affects the life of the furnace tube; if the surface of the steel pipe is relatively rough, the strength of the steel pipe will be reduced, and the furnace tube cracking accident is extremely easy to occur. Therefore, it is necessary to conduct periodic tests on the viscosity, acid value, carbon residue, and flash point of the heat transfer oil, and clean the coking and carbon deposits in the heat transfer oil pipeline when the indicators are exceeded. The prerequisites for heat conduction oil cleaning. Any quality heat conduction oil boiler diesel burner will produce quality deterioration for a long time at high temperature. During this deterioration process, the carbon pollution and carbon deposits produced by it adhere to the pipe wall to form the following six aspects Hazards: 1. Carbon pollution and carbon deposits have insulation and heat insulation properties, which will cause slow heating after fouling and affect work efficiency. 2. Every additional millimeter of carbon pollution on the inner wall of the tube consumes 20-30% more fuel. 3. Due to the unequal carbon pollution thickness in the pipe wall, the working surface temperature is uneven, which affects the product quality. 4. After the formation of carbon pollution and carbon deposits, the acid value will increase, causing corrosion of the micro-battery, and accelerating the aging and damage of the equipment. 5. Due to long-term non-cleaning, a large amount of carbon deposits and carbon pollution are deposited in the pipe bends, forming local overheated gas storage, causing pipe cracks or fuel injection, causing fires, and boiler diesel burners are scrapped. 6. It is beneficial to the regeneration and adjustment of the light oil burner of the heat-conducting oil furnace, and extends the service life of the light oil burner of the heat-conducting oil furnace and the service life of the light oil burner of the heat-conducting oil furnace. The first solution for cleaning boiler diesel burners Chemical cleaning (heating oil boiler diesel burner cleaning) adopts my country's patented technology, combined with the particularity of the internal structure of the heat conduction oil heating system and the persity of materials, determine the following heat conduction oil furnace light oil combustion Machine cleaning program: thermal oil venting-steam flushing-degreasing-descaling cleaning-rinsing-neutralization passivation-steam flushing-inspection and acceptance-nitrogen purge-reset heating 1, steam flushing will The heat transfer oil in the pipeline is vented, and the inside of the pipeline is flushed with steam to remove surface impurities, rust and other dirt. 2. The purpose of degreasing is to remove oily substances in the system, and to infiltrate and transform the scaled substances, creating conditions for the descaling step. The oil stains originally existed on the surface as a spreading oil film. Under the action of preferential wetting after washing, it gradually shrinks into oil droplets, which are finally washed to leave the surface. 3. Decoking and descaling. This procedure is a key step in chemical cleaning. The purpose is to chemically react with the fouling substances through the formulated special coking and descaling agent to form water-soluble substances and be taken out of the system by the cleaning liquid to achieve The purpose of cleaning and descaling. The heat transfer oil is heated and coked on the wall tube, and the coke lump is very hard. For many years, our company has drawn a conclusion from the research and practice of coking removal-the coking removal of heat transfer oil should adopt the comprehensive effect of coking removal: solubilization; adsorption ——The adsorption of the surface active agent on the dirt and the surface of the laundry (furnace tube) changes various substances (such as mechanical, electrical and chemical properties) on the interface and the surface; emulsification——forms a strong interface film, It is conducive to the stability of the emulsion, and the oil stains are not easy to re-precipitate on the surface of the solid (furnace tube). Adding a builder can improve the washing effect. It is conducive to the suspension of dirt particles and prevents the deposition of dirt particles. Together with the effects of temperature (thermal movement) and mechanical force, the optimal washing effect is achieved. 4. Rinsing is to combine the rinsing liquid prepared according to regulations with the free ions remaining in the system to further increase the descaling rate and lay a good foundation for the neutralization and passivation process. 5. Neutralization The neutralization liquid reacts with the remaining rinsing liquid in the system to make the PH value of the entire heat transfer oil heating system meet the specified requirements. 6. The passivation liquid for passivation can form a complete and dense passivation protective film on the clean metal surface. 7. The water rinse after cleaning ensures that all cleaning agents are exhausted and the inside of the pipe wall is clean. 8. Nitrogen purging is to exhaust the residual water in the heat transfer oil heating pipeline as much as possible. Nitrogen or compressed air can be used for purging. The cleaning process of the second solution for the cleaning of boiler diesel burners: discharge and remove old oil → pre-wash → clean → water wash ① → water wash ② → water wash ③ → add new oil → dehydration → normal operation 1. discharge and remove old oil: Use the heating system to heat the heat-conducting oil boiler diesel burner to 70-80℃, and discharge all the heat-conducting oil boiler diesel burners in the system while it is hot. According to the conditions, the residual oil in the system can be released as much as possible. A small amount of cleaning agent makes the oil thin through penetration, peeling, and dissolution, and then drains out of the system. 2. Pre-washing: Add 2% (70-80 kg, a bag of semi-solid, and a bucket of semi-liquid) of the cleaning agent into the system. The solid is dissolved in hot water and then added, and the liquid is added at the same time. Any part of the thermal system (usually through the oil pump through the high oil tank, the same way as refueling) is put into the system, fills the system with clean water, turns on the circulating oil pump to circulate, uses the heating furnace to raise the water temperature to 80℃±5℃, switch The relevant valve of each reactor in the system allows all parts in the system to be circulated separately. 3. Cleaning: Add the cleaning agent to the system according to 6-8% of the total circulation (in order to ensure the effect, please reserve 50 kg, one bucket and one bag). After the solid is dissolved in hot water, the liquid is added at the same time, the same as (2) Put into the system and fill the system with clean water, turn on the circulating pump to circulate, and use the heating furnace to heat the cleaning agent to 90℃±5℃. 4. Water washing: Fill the system with clean water, turn on the circulating pump to circulate, use the heating furnace to raise the water temperature to 90℃±5℃, switch the relevant valves in the system, so that all parts in the system are circulated separately. The third solution for cleaning boiler diesel burner 1. Steam flushing vents the heat transfer oil in the pipeline, and flushing the interior of the pipeline with steam to remove surface impurities, rust and other dirt. 2. The purpose of degreasing is to remove oily substances in the system, and to infiltrate and transform the scaled substances, creating conditions for the descaling step. The oil stains originally existed on the surface as a spreading oil film. Under the action of preferential wetting after washing, it gradually shrinks into oil droplets, which are finally washed to leave the surface. 3. Decoking and descaling. This procedure is a key step in chemical cleaning. The purpose is to chemically react with the fouling substances through the formulated special coking and descaling agent to form water-soluble substances and be taken out of the system by the cleaning liquid to achieve The purpose of cleaning and descaling. 4. Rinsing is to combine the rinsing liquid prepared according to regulations with the free ions remaining in the system to further increase the descaling rate and lay a good foundation for the neutralization and passivation process. Neutralization The neutralization liquid reacts with the remaining rinsing liquid in the system to make the entire system. The consequences of improper cleaning of the heat-conducting oil boiler diesel combustion engine is the first thing to say is water washing. The earliest time when the water-washing heat-transfer oil system appeared, can be traced back to the 1990s. Due to people’s ignorance of environmental protection and the backward technology level, water-based cleaning agents have once become mainstream cleaning products, but companies that have used water-washing heat transfer oil equipment know that the cleaning of boiler diesel burners is not very thorough, and Fortunately, after a long period of shutdown and a long period of dehydration. In many cases, the hard coking water-based cleaning agent in the boiler diesel combustion engine coil does not play any role at all. At the same time, a large amount of waste water is difficult to discharge in the system, which leads to the easy emulsification of the heat transfer oil when new oil is added. , Thereby reducing the service life of the heat transfer oil. Although the traditional solvent cleaning agent cleans thoroughly but the price is too high, it is often not easy to accept. However, some cleaning companies have developed many solvent cleaning products that are reused many times. Although the cost of single cleaning is lower, it is not conducive to heat transfer oil. Life. Because the heat-conducting oil of many companies is mixed in the solvent cleaning agent that is repeated many times, long-term mixing will easily affect the new oil due to the different brand of heat-conducting oil or the production process. This is why the heat-conducting oil should be used when using it. Matching experiment. How to choose a suitable high-temperature heat transfer oil as the heat transfer medium for heat transfer oil boiler diesel burners. The following factors need to be considered: 1. The heat transfer oil can be selected according to the working temperature range of the heat transfer oil boiler diesel burner. The service life is inversely proportional to the operating temperature. Therefore, when selecting heat transfer oil, you should consider not only meeting the temperature requirements of the process production, but also meeting the extension of the service life of the heat transfer oil. 2. Heat conduction oil boiler diesel burner should choose heat conduction oil with good thermal stability. The thermal stability of heat conduction oil guides the ability of the heat oil itself to resist high temperature deterioration. The quality of thermal stability directly determines the use of heat transfer oil. Life is one of the key factors for selection. 3. The heat-conducting oil boiler diesel burner should choose heat-conducting oil with high boiling point and low vapor pressure. Heat-conducting oil with high boiling point is not easy to cause fire. Most of the high-temperature heat-conducting oil used below 280℃ will not produce under normal operating conditions. Very high vapor pressure. Selection and use of cleaning agent for thermal oil boiler diesel burner 1. Water cleaning contains alkaline substances, and a large amount of waste water will be generated during the cleaning process of thermal oil boiler light oil burner, so it is difficult to meet environmental protection standards. Gradually began to be eliminated. 2. Although the on-line cleaning of the light oil burner of the heat-conducting oil furnace should be better in theory, because of the uneven quality of domestic heat-conducting oil, the base oil of many heat-conducting oils is very poor, plus domestic heat conduction The overall level of the oil burner light oil burner boiler diesel combustion engine is limited, so the maintenance and use of the heat transfer oil burner light oil burner is not good. Under this condition, the online cleaning agent for the heat transfer oil burner light oil burner is basically Can not meet the cleaning requirements (of course, with the improvement of the quality of heat transfer oil and the quality of boiler diesel combustion mechanics, the online heat transfer oil cleaning agent should be gradually promoted in the next 5 years). The main cleaning principle is to rely on the action of the polar group molecules to make the cleaning agent quickly penetrate into the grease layer, and through special chemical action to decompose the insoluble grease of large molecules into the oily structure of small molecules, thereby removing the creamy grease. After being decomposed, it is integrated into the heat transfer oil, and the oil dirt is removed with the physical action of the circulating flow of the heat transfer oil. [Product features] 1. Simple to use: directly add through the high slot, the temperature is controlled at 100℃-180℃. 2. Low addition amount: The addition amount is 10%-15% of the system oil volume, so there is no need to drain oil from the system. 3. Safe and fast: After the cleaning agent is added to the high tank, open the auxiliary exhaust valve, because the density is relatively large, it will slowly enter the system, and the grease on the pipeline will slowly disperse and dissolve. As time progresses, the temperature difference and pressure of the external heater gradually return to normal. 4. Thorough cleaning: The cleaning efficiency of the pipeline inside the system is as high as 95%. 5. Safe and harmless: harmless to human body and natural environment, good miscibility with heat transfer oil, and it runs directly in the normal operating system. High environmental protection: There is no discharge of waste water and waste gas in the whole cleaning process. [Scope of application] Various boiler diesel burners and their pipeline systems using heat transfer oil as the medium. [Usage method] 1. First, reduce the temperature of the system to the range of 100℃-180℃ (if the normal production temperature of the system is already in this temperature range, online cleaning can be carried out without cooling). 2. Then, add the KFD-607B cleaning agent calculated at 10%-15% into the heat-conducting oil furnace light oil burner system through the high slot. When adding, add in batches and slowly. (If it is added in one time, it will cause large grease stains on the inner wall of the pipe to fall off, which is not conducive to the smooth cleaning). 3. After adding the cleaning agent, pay attention to the pressure change of the pressure gauge. When the pressure changes greatly, clean the filter screen in time to prevent the dissolved oil tar and large particles of grease from blocking the filter screen. 4. As time progresses, the temperature difference of the external heating pipe gradually returns to normal, and the pressure gauge returns to normal. 5. During the cleaning process, the end point of the cleaning can also be determined by observing the falling and coking at the filter screen. The reduction of the falling matter proves that the system has been basically cleaned. 6. Cycle cleaning for about 5-10 days, after cleaning, just replace the heat transfer oil. ! If you are interested in diesel combustion engines, please contact us for a quote!