Thread Content
Chemical processing unit equipment – Separation and filtration equipment. Filters are devices that utilize porous filtering media to retain solid particles in mixtures of liquids and solid particles, thereby achieving separation between solids and liquids. Primarily used in refineries for the separation of oil from wax, such as the paraffin dewaxing vacuum drum filters and the vacuum drum filters in PTA plants. Currently, abroad, rotary drum vacuum filters are evolving toward larger sizes, higher speeds, greater precision, and full automation. In China, the design and manufacturing technologies introduced from the Italian company EIMCO were adapted, improved upon, to develop a complete set of processing, assembly, and welding techniques. In contrast, the main gaps lie in insufficient understanding of market development and product demands, low innovation capabilities, and poor ability to absorb the essence of imported technologies. Centrifuge: A centrifugal separator is a machine that uses centrifugal force to separate the various components in mixtures of liquids and solid particles, or of liquids with each other; it is also known as a centrifuge. There are mainly vertical and horizontal screw-discharge sedimentation centrifuges. Centrifuge technology abroad has developed rapidly, and it has become more specialized and standardized ； The domestically developed El-type LWFl000-N and LWFl050-N centrifuges have been used respectively for the separation of suspensions in high-density polyethylene plants with capacities of 70,000 to 100,000 tons per year. The LWl200x1980 type centrifuge developed has been used for the dewatering of PTA slurry in plants with a capacity of 225,000 tons per year, and the diameter of its drum reaches φ1200mm. However, vertical centrifuges are still in the initial stage of imitation, and the main gaps compared to foreign ones lie in design technology, as well as in the scaling up and serialization of products. Drying and evaporation equipment Drying equipment: It is a type of mechanical device that uses heating to vaporize and remove the moisture (usually referring to water or other volatile liquid components) from materials, thereby obtaining solid materials with a specified moisture content. The manufacturing diameters of Mitsubishi Heavy Industries Shipbuilding in Japan, Tsukishima Machinery, and FAUVET-GIREL in Germany reach over φ4000mm. The 200,000 tons/year HDPE steam pipe rotary dryer and the 400,000 tons/year TA plant steam pipe rotary dryer have been localized. The gap mainly lies in the larger-scale equipment; for the large dryers in the upcoming polyethylene and polypropylene plants with capacities of 400,000–500,000 tons per year, as well as the 600,000-ton-per-year polyester plant, technology still needs to be developed in China. Mixing equipment Mixing equipment is a machine that uses mechanical force and gravity, among other means, to evenly mix two or more materials together. They are divided into four categories: mixers for gases and low-viscosity liquids, mixing equipment for medium-to-high viscosity liquids and pastes, mixers for thermoplastic materials, and mixing equipment for powdered and granular solid materials. Mitsubishi Electric has recently introduced the new FX2N-5A hybrid converter. The technology of domestic mixing equipment needs to be improved. Heat exchange equipment Heat exchange equipment is an important type of equipment in chemical production. Almost all industrial processes involve heating, cooling, or condensation steps, which makes it a crucial device for energy savings as well. With the enlargement and increased efficiency of industrial plants, heat exchangers abroad are also becoming larger, evolving toward lower temperature differences and lower pressure losses. Plate-fin heat exchangers (cold boxes): Cold boxes are primarily used in ethylene cracking, air separation, and natural gas liquefaction. The key technologies involved are design and manufacturing techniques; companies such as the U.S.-based S-W Company and Germany’s Linde Company have relatively advanced and mature technologies in this area. Hangzhou Oxygen Generator Factory has introduced key processing equipment from the United States – large vacuum brazing furnaces – which have enabled the design quality and manufacturing capabilities of cold boxes to approach and reach international advanced levels; these furnaces have been used in the renovation projects of ethylene plants in Yanshan, Yangzi, Shanghai, and other locations. Foreign countries already have 9.0 MPa cryogenic tanks, while China has not yet mastered the design and manufacturing technology for high-pressure cryogenic tanks, and there is a significant gap in fractional condensation and distillation technologies. Plate-and-shell heat exchangers: Only the French company Packinox is capable of producing those used in catalytic reforming and hydrogenation units, with a maximum heat exchange area of 8000 m2. The largest heat transfer area developed domestically is 3000 m2; the main difference lies in the fact that although the area of each individual chip is the same, the heat exchange area is smaller. Extrusion granulation equipment Extrusion granulator: This equipment enables the production of polyolefin pellets from polymers through processes such as mixing, extrusion, and granulation, to facilitate transportation. Abroad, only a few companies such as WP in Germany and Nippon Steel Corporation possess the capability to design and manufacture complete sets of large-scale mixing and granulation machines, with the mainstream trend moving towards twin-screw mixing and granulation units. The development pace in our country is relatively slow; at present, most of the machines developed and manufactured are of medium and small scale. After undergoing operational testing, the ABS mixing and extrusion machines with a capacity of 10,000 tons have met the design requirements in terms of their key technical specifications. At present, all extrusion granulators in large and medium-sized polyolefin production facilities rely on imports. This post was last edited by brainandrain on 2009-3-18 15:04.]