Case study of high pressure water cleaning in the petrochemical industry

High-pressure water jet cleaning technology is widely used in various departments to clean various chemical containers, heat exchangers, coolers, condensers, pipes, tube bundles, defocusing, descaling, descaling, hydraulic, cleaning and other cleaning operations.

For the cleaning of heat exchange equipment of foreign petrochemical enterprises, 80% use high-pressure water jet cleaning, and 10%-20% use chemical cleaning. High-pressure water jet cleaning and steam washing quality are equivalent, but the efficiency is increased by 10% - 40% , achieving safe and civilized operation without burning, non-toxic and environmental pollution.

( 1 ) Storage tanks are process equipment with a large number of petrochemical plants, many types of specifications, and a large variety of storage media. Such as synthetic rubber glue storage tanks, need to be cleaned regularly. In the past, it was removed with a manual spatula, except for a few square meters a day. High-pressure water jet cleaning is used, the pressure is 120Mpa, the flow rate is 34L / min high-pressure water generating device, 2 - 3 single-nozzle spray gun, less than 10h can clean a glue tank, improve efficiency dozens of times.

A : When the tube heat exchanger is completely blocked, chemical cleaning can not be carried out. The manual mechanical method can reduce the pipe fittings with low efficiency of steel brazing . The high pressure water jet cleaning technology is adopted, and the pressure of 150MPA is selected , and the water flow rate is 27L / min , 10 Clean up for many hours. A chemical company affiliated to Huayi Chemical Group Co., Ltd. has 2 sets of 9 coils of ethylene glycol storage tanks , which are cleaned with high-pressure water jet for one day. Cleaning 278 sets of various heat exchangers ; container 1.5-350 cubic meters of various storage tanks, 29 reactors , pipeline Φ 50 - Φ 450 length 1380 meters; cleaning tray, rotor, partition, silencer 383 kit A total cleaning area of 64,246 square meters In total, the company earned a profit of 1.66 million yuan in revenue and greatly improved the efficiency of the plant.

( 2 ) Cleaning case of high pressure water jet in the inner wall of power plant ash pipe:   

      A certain production line under the Beijing Yanshan Petrochemical Group: the captive power plant is a thermal power plant, and the main fuel is pulverized coal. In order to concentrate the fly ash slag to the ash yard on the bank of the Yangtze River, there is a pumping station, and three wet ash pipes with a diameter of 425 mm , a wall thickness of 12 mm and a length of 2500 m are alternately used. Wet ash is transported by water pressure. In the production process, scale is formed on the inner wall of the process material and water system. The thickness is 20-60mm , wet gray-gray, layered structure, hard, dense and shaped like a tile, which affects normal operation. The chemical composition of scale is as follows:

Component CaCO 3 CaSO 4 Ca 3 (PO 4 ) 2 aluminosilicate % (mass) 92 <20 <0.8 <5

It is a typical CaCO 3 scale. In order to be safe, stable, long-term, full-load operation, under normal circumstances, cleaning every two years can ensure the full-load operation of the production. In the past, under the guidance of Japanese experts, the entire tube system was pressurized with acid cleaning, soaking, venting, and circulating chemical cleaning. Due to the complicated air and pipeline, the bridge and the road turn and turn, the pipeline is high and low, so that the acid washing liquid is difficult to fill the entire lumen, and the pickling is not complete. The whole pipeline pickling used 400t pickling solution and 100t neutralizing agent costed a total of 1.5 million yuan. Now I use the high-pressure water machine company of our Degao cleaning group cleaning equipment, the pressure is 110Mpa , the flow rate is 52L / min , the power is 139KW , every 30M section, the segment cleaning effect is good.

( 3 ): Case of heat exchanger cleaning of Jinzhou Petrochemical Company:

A : More than 10 sets of tubular carbon steel heat exchangers of a refinery, rubber plant and cold-exchange workshop of Jinzhou Petrochemical Company were blocked by scale and sediment, and cleaned by high-pressure water jet technology. The cleaning area is nearly 5000M 2 The cleaning pressure is 200Mpa , the flow rate is 20L/M , and each cleaning time is 70-100h . The surface of the cleaning equipment is exposed to metallic luster without damage.

B : 12 heat exchangers in a cracking workshop of a chemical plant of Beijing Yanshan Petrochemical Company , 8 heat exchangers in a polystyrene workshop, and 1 heat exchanger in a styrene workshop are all cleaned by high-pressure water jet technology. A total of 7772 square meters, cleaning work pressure 200Mpa , flow 20L / M , cleaning time less than 90h . The cleaning effect is very good and the equipment is exposed to metallic luster.

( 3 ) Cleaning scheme of boiler heating surface of Gansu Jingyuan Power Plant:

       Jingyuan Chemical Factory Power Plant 3 # 炉炉膛水冷壁油石焦垢, thickness 1 mm - 3mm , cleaned with high pressure water jet. Cleaning area of 1200 square meters , cleaning work pressure 950 kg , flow 62L / MIN cleaning time 5h . After cleaning, the descaling rate is 95% .

( 4 ) Case analysis of the cleaning of the inner wall of the butene storage tank:

     The tank of the Lanzhou 303 factory has a diameter of 12.5m and a volume of 100 square meters of butadiene spherical storage tank. The thickness of the peroxide on the inner wall is 1mm-3mm , and the high pressure is adopted by the three-dimensional rotating nozzle of our Degao Group. Water jet cleaning, cleaning working pressure 140Mpa , flow rate 44L/M ; cleaning time In less than 10h , the descaling rate is greater than 90% .

( 5 ) Analysis of the cleaning of gas pipelines:

Anshan has a gas pipeline of Φ 700 and a length of 1000 m . The inner wall is covered with heavy oil, coal tar and other scales, and some pipes are blocked. It is cleaned by high-pressure water jet. The cleaning working pressure is 70Mpa , the flow rate is 84L/MIN, the cleaning time is less than 160h , and the descaling rate is over 90% .

( 6 ) Analysis of the cleaning case of the condenser:

      Wuhan Boda Chemical Co., Ltd.: There is a 6000W unit in the self-supplied thermal power plant. Due to the fouling of the condenser, the steam condensation effect is affected, and the vacuum in the system is reduced. The unit can not work at full load, and can only generate 4200KWh per hour ; The electricity is calculated at 0.2 yuan, and the loss is more than 8,000 yuan per day . The factory originally used steel brazing rods and drill bits to remove dirt. It not only has high labor intensity and low efficiency, but also easily damages the steel pipe, so that the condenser is scrapped, and the scale removal effect is not ideal. Later, the high-pressure water jet cleaning machine is used for cleaning. The working pressure is 1500 kg, the flow rate is 27L/MIN ; the average pipe is cleaned every 30s , more than 2000 pipes are cleaned in less than 20h , the scale is covered with hundreds of kilograms, the cleaned condenser works normally, and the steam condensation temperature is consistent. The unit is required to generate electricity at full load.

( 7 ) Boiler cleaning case analysis:

      A chemical plant affiliated to Huayi Chemical Group Co., Ltd.: 2 sets of 130t cyclone steam boilers with self-provided thermal power plants The ash is severely blocked, and the air preheating pipe is cleaned by means of steel casting sand. As a result, the steel grit used not only fails to effectively control the ash blockage, but also forms a new blockage, which greatly reduces the heat exchange efficiency. The ground affects the normal combustion of the boiler, reduces the steam production, seriously affects the normal combustion of the boiler, reduces the steam production, and then uses the high-pressure water jet to clean, after 32 hours , the cleaning is completed, and the heat exchange capacity is tested after normal production. The amount of steam produced has reached the rated value.

( 8 ) Case analysis of storage tank cleaning :      

The detergent project introduced by a refinery of Jinzhou Petrochemical Company from the United States has built a number of large-scale storage tanks of different types. In order to ensure the quality of the products, cleaning must be carried out to remove impurities such as rust, oil, dust and the like. The high-pressure water jet cleaning combined with the chemical cleaning method is used for cleaning. The cleaning process procedure is: high-pressure water jet cleaning - phosphoric acid acidification - high - pressure water jet cleaning - phosphoric acid acidification - high - pressure water jet cleaning - coating Neutral oil protection.

The purpose of phosphoric acid acidification treatment is to remove rust, and the formula is as follows: 85% H 3 PO 4 30kg ;

100kg of purified water ; 1~1.5kg of zinc oxide ; Chromium trioxide 0.5kg . After cleaning, the surface of each tank is free of dust, rust and impurities, ensuring product quality.

( 9 ) Case analysis of railway chemical tanks:

A : Important tools for transporting petrochemical products and raw materials in petroleum and chemical industries such as Shanghai, Beijing, Wuhan, Shenzhen, Kunshan and other railway sections. The purity of petrochemical products is very high, and many products are flammable, explosive and toxic. Since the cleaning product medium also contains chemical oil, it is very effective to use 180 kg, flow rate of 1260 L/H ; 1500 kg, flow rate of 27 L /M hot water high pressure water machine. Railway chemical tanker must be replaced before it can be replaced or repaired. The inner wall is thoroughly cleaned to ensure the quality and safety of the petrochemicals shipped.

B : Yanshan Petrochemical Washing Station uses high-pressure water machine to clean chemical tanker with pressure of 350 kg and flow rate of 23 L/M . The effect is very good. When the high-pressure water machine cleans the railway chemical tanker, the flow rate of cleaning water must be less than or equal to ensure the cleaning quality. pumping means pumping liquid flow, wherein a chemical tanker ships required 40--60MIN, 2 stands th annual capacity of 3,000 washing. Cleaning quality: no impurities in the tank, no floating embroidery, no obvious wet marks, clean, smooth inner surface without yuba. At the same time, using the Japanese GS-85N instrument to conduct oxygen measurement and explosion inside the tanker, the oxygen content is 21% , and the explosion is 0 , which is in line with the requirements for entering the tanker and the hot fire.

If you have any product needs or questions, please call the technical center of Kaidi Chemical Industry Cleaning Division to request cleaning solutions and quotations.