79- Technical design of multi-factor cyclone separators as dry gas cyclone hydrocarbon removal units and dry gas cyclone liquid separation tanks in dry gas desulfurization units

This post was last edited by luoli519 on 2017-2-5 at 17:02. Not only do petroleum refining companies use MDEA amine towers to absorb and desulfurize dry gas, but the fine chemical industry also employs amine towers to purify process gases. Coal chemical plants use low-temperature methanol washing absorption towers to remove acidic gases from syngas, while coking plants that produce LNG from coker gas likewise use amine towers to purify such gas. Even companies that produce synthetic natural gas from coal utilize TEG absorption towers for dehydration and removal of acidic gases. In the gas purification process using a solvent absorption tower, an efficient gas-liquid separator must be installed to remove droplets and foam from the gas streams entering and leaving the absorption tower. Otherwise, the incoming gas will carry light hydrocarbons into the absorption tower, where they accumulate to form a layer of non-polar light hydrocarbons; this hinders the polar solvent from absorbing the acidic gases, thereby significantly reducing the efficiency of the absorption tower’s operation ； The vent gas carries the polar solvent from within the tower into the downstream pipelines and equipment, not only causing a sharp increase in solvent consumption within the tower but also leading to operational failures in the downstream systems.

In various industries and different devices, there are several types of technologies and equipment for separating gas and liquid from the airflow entering and leaving the absorption tower.

This post was last edited by luoli519 on 2023-9-27 15:55. In the natural gas processing industry, MDEA absorbers and TEG absorbers are widely used. The gas-liquid separation technologies and equipment used for the inlet air in absorption towers include high-end devices such as horizontal double-tube filter-coagulator separators, mid-range devices like vane separators, and low-end options such as mesh-type separation tanks and purely gravity-based sedimentation tanks. For the gas-liquid separation technology and equipment used in the exhaust gas from absorption towers, vane separators are commonly employed; a few companies, however, use lower-grade mesh-type separation tanks or pure gravity sedimentation tanks.

This post was last edited by luoli519 on 2023-9-27 at 15:55. In the coal chemical industry and the broader chemical industry, low-temperature methanol wash absorbers and MDEA absorbers are widely used. For the inlet and outlet gases of absorption towers, vane separators are commonly used; however, a few companies employ low-end mesh-type separation tanks or pure gravity sedimentation separation tanks.

This post was last edited by luoli519 on 2023-9-27 at 15:56. In the petrochemical refining industry, MDEA absorbers andMEA absorbers are widely used. The gas-liquid separation technologies and equipment used for the inlet and outlet gases of absorption towers are mostly low-end types such as mesh separation tanks and purely gravitational sedimentation tanks; in recent years, vane separators and multi-factor cyclone separators have begun to be used.

This post was last edited by luoli519 on 2023-9-27 at 15:56. Based on our many years of experience in international dynamics separation technologies, as well as in the design and operation of related equipment, we offer the following suggestions: 1. The horizontal twin-tube filtration and coagulation separator is undoubtedly the most advanced type of equipment; it has high manufacturing costs, requires additional backup machines and spare parts, and entails extremely high operational and maintenance expenses. Apart from being used in high-pressure and ultra-high-pressure natural gas transmission projects and the LNG industry, it is less utilized in other industries and applications, mainly due to its poor cost-performance ratio. 2. Feather leaf separators have shown remarkable performance in recent years. Developing from the first generation of Chevron flat-plate baffles in the mid-20th century to the fifth generation of vane-type separation internals today, these devices have seen significant improvements in terms of quantitative separation efficiency, operational flexibility, low operating pressure drop, resistance to clogging, and extremely low operating and maintenance costs. As a result, they represent separation technology equipment with high cost-performance competitiveness, and are preferred in many industries. It should be noted, however, that the feather leaf separator is a device based on pure kinetic separation technology; it requires a specialized company in kinetic separation technology to carry out accurate system design using its precise kinetic separation calculation platform in order to fully utilize its efficient and quantitative separation capabilities. A vaned separator that has not been accurately designed using a platform based on precise dynamic separation calculations will not exhibit excellent overall performance! 3. Screen-type separation tanks and purely gravity-based sedimentation separation tanks have low separation efficiency and limited operational flexibility; they are part of the traditional, simple-structured separation equipment, and are gradually being replaced by high-efficiency gas-liquid separators. Many owners have already begun to carry out technical upgrades and renovations on their existing screen-type separation tanks and gravity sedimentation separation tanks.

This post was last edited by luoli519 on 2023-9-27 at 15:57. The multi-factor cyclone separators mentioned in the main text, such as dry gas cyclone hydrocarbon removal units and dry gas cyclone liquid separation tanks, also belong to equipment based on pure kinetic separation technology. Under the same medium and low pressure conditions, the manufacturing cost of the internals for multi-factor cyclone separators is often higher than that of vaned separators, which reduces the cost-effectiveness of multi-factor cyclone separators. The core competitive advantage of multi-factor cyclone separators lies in gas-solid separation or the purification of air streams containing a high proportion of solid particles; especially in high-pressure and ultra-high-pressure air purification applications, no other type of cyclone separator can compare to them. However, it is still necessary to remind engineering companies and owners that cyclone separators are devices based on dynamic separation technology; they must be accurately designed by professional companies in this field using their specialized platforms for precise dynamic separation calculations, in order to fully leverage their core competitive advantages. Multi-factor cyclone separators that are not designed with precision using a dynamics separation-based calculation platform for accurate system design will not possess a competitive advantage; in fact, their separation performance can be quite poor! Furthermore, the theoretical operating margin ratio of the multi-factor cyclone separator is 5.6:1; in situations with large fluctuations in operating conditions, it is advisable to avoid using standard multi-factor cyclone separators, and instead a more specialized design for such separators is required.

In this post, further discussion is carried out using as an example the dry gas cyclone dehydrogenation unit and the dry gas cyclone separation tank of the 2.1 million tons per year feedstock hydrogenation unit for an olefin production project via heavy wax oil cracking at a coastal petrochemical company, operated by a Sinopec engineering firm.

The process operating parameters of the dry cyclone stream hydrocarbon removal unit are as follows: 1. Operating temperature: 40℃； 2. Operating pressure: 0.6 MPaG ； 3. Maximum gas flow rate under operating conditions: 942.86 m^3/h ； 4. Average molecular weight in the gas phase: 28.51 ； 5. Viscosity in gas phase: 0.011 cp ； 6. Vapor density: 8.10 kg/m^3; 7. Average molecular weight of the liquid phase: 68.83 ； 8. Viscosity of the liquid phase: 0.281 cp ； 9. Liquid surface tension: 14.49 dyne/cm ； 10. Liquid phase density: 627.3 kg/m^3.

The process operation parameters for the dry gas cyclone separation tank are as follows: 1. Operating temperature: 43℃； 2. Operating pressure: 0.5 MPaG ； 3. Maximum gas flow rate under operating conditions: 965.34 m^3/h ； 4. Average molecular weight in the gas phase: 28.45 ； 5. Viscosity in gas phase: 0.011 cp ； 6. Vapor density: 7.25 kg/m^3; 7. Average molecular weight of the liquid phase: 24.16 ； 8. Viscosity of the liquid phase: 0.397 cp ； 9. Liquid surface tension: 33.64 dyne/cm ； 10. Liquid phase density: 997.44 kg/m^3.