Product refining unit
The product refining unit includes three parts: gasoline sweetening part, dry gas and LPG desulfurization part and diesel oil refining part, including dry gas desulfurization tower, gas holder gas desulfurization tower, LPG desulfurization extraction tower, oxidation tower, rich liquid flash tank, disulfide separation tank and tail gas absorption tank. These towers cover plate tower and packed tower, mainly packed tower, and the main internal components involved include metal bulk packing Coalescing packing, liquid distributor, liquid collector, packing grid, packing grid support, tray assembly (float valve, tray plate, downcomer, receiving tray, liquid seal tray and corresponding support beam), oil collecting tank, gas-liquid feed distributor, distribution pipe, bolts, nuts, clips, washers and other fasteners.
● Main bulk packing
(1) Metal flat ring bulk packing
Stainless steel flat ring bulk packing includes QH-1, QH-2 (also known as plum shaped flat ring, namely, inner curved rib flat ring packing) and QH-3. The performance of this kind of packing is obviously better than that of other bulk packing when it is used for liquid-liquid extraction of low interfacial tension system. The flat ring packing is suitable for liquid-liquid extraction process and also for gas-liquid mass transfer process.
(2) Metal rectangular saddle ring bulk packing
The shape of metal rectangular saddle ring bulk packing is a ring saddle structure composed of ring and saddle shape, with tongue shaped reinforcement inside. It is composed of two curves, the upper arc is an elliptic curve, and the lower arc is a semicircular curve. The surface of the finished rectangular saddle ring bulk packing is smooth without rust marks, cracks and burrs. The packing has the advantages of large flux, low pressure, high efficiency, good strength and rigidity, and is a widely used bulk packing.
(3) Metal Ball Ring Bulk Packing
The shape of metal ball annular bulk packing is a cylinder with the same height and diameter and several windows on the surface. This filler was developed by BASF Company of Germany in the 1940s and punched with metal sheet. The total area of the general opening is about 35% of the entire ring wall area. Compared with Rasi ring packings of the same specification, as Bauer ring packings have many window holes on the ring wall, allowing the gas and liquid in the tower to pass through the window freely, the distribution of gas and liquid in the packing layer has been greatly improved compared with Rasi ring packings, and its separation performance has been significantly improved. Bauer ring packings are still one of the main ring packings currently used.
(4) Liquid distributor
Trough liquid distributor
The tank type liquid distributor consists of a main tank (primary tank) and a sub tank (secondary tank), and the main tank is placed above the sub tank. The return liquid and feeding liquid enter the main tank from the feeding pipe above, and then are distributed to each sub tank in proportion from the main tank. The two-stage trough distributor has simple structure and is easy to enter the tower from the manhole for installation; The air lift channel is uniform, and the free sectional area is large. It is often used with a liquid collector in a packed tower, which can better collect and evenly distribute the feed liquid. The trough liquid distributor is a kind of liquid distributor with better comprehensive performance.
Trough tray liquid distributor
The trough pan type gas-liquid distributor is a gravity type liquid distributor, which is composed of rectangular riser, angle steel and channel steel shaped liquid guide pipe, dovetail or channel steel shaped liquid retaining cap, planking, support ring and support beam. The trough tray type gas-liquid distributor has the advantages of uniform gas and liquid distribution, pressure reduction, anti entrainment, low occupancy, convenient installation, etc., and is suitable for feeding, side line production, liquid collection and redistribution, etc. It is one of the liquid distributors with better comprehensive performance when it is applied to packed tower.
(5) Liquid collector
The liquid collector is applied between the packed beds, which makes the gas distribution and liquid mixing between the packed beds even. The combination of the liquid collector and the trough liquid distributor is conducive to the uniform distribution of gas and liquid between the packed beds.
(6) Packing grid
The packing pressure ring adopts a permeable grid plate structure, which has low space occupation and strong permeability, will not affect the gas-liquid mass transfer of the packing, and can also reduce the end effect of the packing.
(7) Packing support
Packing grid support: the packing grid support is applied to the packed tower, which is one of the better structured packing supports at present. The packing grid support has a large free sectional area, and the packing hump support: the hump support is applied to the packed tower, which is one of the better bulk packing supports at present. The hump has a long side hole, which is formed by stamping with steel plates. Its liquid flux can reach 200m3/m2h, and the large pressure drop is 69Pa, It is applicable to all kinds of bulk packings above 25 mm, so the width of the side hole shall be such that 25 mm packings will not leak out. For smaller packings, a layer of small steel mesh can be covered on the hump.