Composite Cooling Products, which are used in petrochemical engineering, are an efficient cooling solution designed, researched and developed by Luoyang Long Hua Heat Transfer & Energy Conservation Co., Ltd. Based on the transfer of latent heat and sensible heat and the optimized combination of evaporative, air-cooled and water-cooled methods, the cooling equipment is of stable structure and possesses a wide range of applications. It also has superior energy-conservation, water-saving and environment-friendly functions.
Composite Cooling Products can replace the three-level series system of "air cooler + water cooler + water cooling tower" in efficiency, and are widely used at the top of petrochemical and chemical towers or for the compressor after condensation and cooling of the cooling medium.
Petrochemical field: atmospheric vacuum, catalytic cracking, catalytic reforming, aromatic hydrocarbon, hydrocracking, hydrorefining, gas fractionation, alkene, PX, PTA, MTBE, MTO, MTP, MTA, EO/EG sulfur recovery, C4/C5/C9 deep processing, natural gas cooling, etc.
1. Optimal ratio of the latent heat transfer and sensible heat transfer, reasonable temperature gradients, and high cooling efficiency
2. Adoption of inclined pipes which are lower pressure than traditional horizontal pipes
3. Low initial investment and high cost efficiency
4. Basically eliminating the "white fog" by using double water collection, uniform air distribution and efficient dehydrator and fin pre-cooler; reducing energy usage by 10-30% and water savings is increased by 15-40% by recycling the wet air discharged from the evaporator in the air-cooled section
5. Takes up little floor area and is installed according to your arrangement
6. Greatly relieves the scale formation of high temperature refrigerants in the evaporator section after being pre-cooled in the air-cooled section. Can be run without water during the winter, significantly reducing water consumption and operating costs
7. Combination of air cooling and evaporative cooling; wide range of applications and excellent in fog and scale prevention
8. Uses frequency conversion and automatic control technologies and allows for precise control of process indicators
9. Flexible structure, eliminating thermal stress and safe and reliable
10. Modular design, easy to manufacture, install, repair and maintain
11. Hot-dip galvanizing of all heat transfer parts ensures a long service life.
Compound-type Efficient Condenser (cooler) is similar to intensive equipment setups integrating the three-level series system of "air cooler + water cooler + water cooling tower", but boasts "three recycling and three differences" compared with the traditional series cooling system:
1. "Three recycling" refers to the equipment’s ability to reuse wind and water 3 times. The 1st wind recycling occurs when the wind is blowing to water tank level from the lowest point of the evaporation light pipe, during which wind of the lowest temperature is frequently cooling the circulating water and keeps water temperature in the tank constant. The 2nd wind recycling occurs outside the water film of the evaporation light pipe where the higher speed air generates local negative pressure which not only facilitates the evaporation of water film but also absorbs the water vapor to avoid the formation of pressure-out. When wind blows upwards to the exterior of the fin the flow state is shifted to turbulent flow from laminar flow. In this state, the air is of a higher heat transfer coefficient and temperature change (normally 10-15℃). The high-temperature air is discharged from the air duct by the induced draft fan which in turn causes the 3rd recycling of wind.
The 1st water recycling occurs at the bottom of the evaporation light pipe where the water first contacts the air from the outside in a counter current. Rainstorm water can completely rinse impurities that were mixed in the air to the bottom of the water tank to keep clear air passing through the light pipe and reducing the scaling and blocking at pipe joints. The 2nd water recycling occurs outside the evaporation light pipe. All rows and lines of pipes shall be completely covered evenly by water films, without any dry points, to prevent scaling and corrosion. Most of the liquid water is intercepted by the upper water collector of the spraying unit, and saturated water vapor will be intercepted again when flowing through the exterior of finned tube bundles. This causes most of the saturated water vapor to turn into unsaturated water vapor which is discharged from the air duct as it’s passing by the overheat section of the fins. “White Fog” does not occur and the heat transfer coefficient of air outside the wet fins is increased. After these processes are completed, the water’s 3rd recycling is realized.
2. "Three differences" means that this equipment is substantially different from traditional air coolers, water coolers and water cooling towers. To start, the equipment differs from other air coolers in corrosion prevention of the fins. The traditional air cooler generally runs under dry conditions so the outer side of its aluminum fins needs no anti-corrosion paint. In contrast, the outer side of the compound-type cooling equipment normally operates under wet conditions so its finned tube bundles should receive antiseptic treatment, generally an overall hot-dip galvanizing after the processing of the steel tubes and sheets are completed. The equipment differs from water coolers with the inclusion of light pipes. For traditional water coolers, the cooling medium passes through the tube side and the thermal medium passes through shell side. In the compound-type cooling equipment, the thermal medium passes through tube side and wind and water pass outside the tube meaning the exterior of pipes is also be treated by hot-dip galvanizing. The compound-type cooling equipment differs from other water cooling towers in stuffing. Traditional water cooling tower generally has stuffing, while compound-type equipment has no stuffing in the counter current section that contacts wind and water. Additionally, water cooling towers are normally installed on the ground, while the compound-type equipment is mobile, and can be installed on pipe racks, platforms or roofs, greatly increasing its flexibility.