Flowing pilot

The use of acidic chloroaluminates as alternative liquid acid catalysts for the allcy-lation of light olefins with isobutane, for the production of high octane number gasoline blending components, is also a challenge. This reaction has been performed in a continuous flow pilot plant operation at IFP [44] in a reactor vessel similar to that used for dimerization. The feed, a mixture of olefin and isobutane, is pumped continuously into the well stirred reactor containing the ionic liquid catalyst. In the case of ethene, which is less reactive than butene, [pyridinium]Cl/AlCl3 (1 2 molar ratio) ionic liquid proved to be the best candidate (Table 5.3-4). 

Figure 7-5B. Safety relief valve mechanism as connected to a non-flow (zero flow) pilot safety relief valve. By permission, Anderson Greenwood and Co.

Flowing pilot A pilot design that continuously discharges the fluid through the pilot throughout the relieving cycle of the pilot-operated safety relief valve (POSRV). 

Non-flowing pilot A pilot in which the fluid flows only just enough to enable a change in the position of the piston in the main valve it controls. During the relief cycle, there is no fluid going through the pilot. 

Here again, there are different designs on the market, but it is important to use non-flowing pilots so that during a relief cycle fluid does not flow through the pilot, causing impurities to damage it. 

The use of non-flowing pilots is highly recommended for liquids and especially flashing dual-flow applications where the amount of mixture (vapour/ liquid) is not exactly known. 

Primarily, it is important to always make sure to use a non-flowing pilot-type as otherwise the particles continue to flow through the pilot and will block it. 

In any case, it is imperative that the pilot be of a non-flowing design. A pilot is said to be non-flowing when it does not pass any fluid when the main valve state (opened or closed) does not change. The main valve may be open and flowing, but the non-flowing pilot will not flow until the valve has to... 

The experiments were carried out in a fixed bed down flow pilot plant. The oil feed and hydrogen were premixed before entering the reactor The light gases were separated from the liquid product in a high pressure separator. The liquid, after been stripped with nitrogen, was analyzed. 

Bhattacharyya el al.s have developad a process to remove Cr6 by reducing it to Ci3 with bisulfite followed by precipitation as the hydroxide with NaOH and precipitate flotations with sodium dndecylsulfate (SDS)4 A 99% removal rare was achieved in the pH range 7,0-8.8. This method was modified later for use in a small, continuous flow pilot plant.1... 

The biphasic system has been evaluated in terms of activity, selectivity, recyclability and lifetime of the ionic liquid, in a continuous flow pilot operation. A representative industrial feed (Raffinate II), composed of 70 wt.% butenes (27% of which is 1-butene) and 1.5 wt.% isobutene (the remainder being n-butane and isobutane) enters continuously into the well mixed reactor containing the ionic liquid and the nickel catalyst. Injection of fresh catalyst components can be made to compensate for the detrimental effects of random impurities present in the feed and for a slight catalyst carryover by the organic phase. The reactor is operated... 

The Difasol biphasic system has been evaluated in terms of activity, selectivity, recyclability, and lifetime of the IL by continuous-flow pilot plant operation. During a typical run, feed in its liquid state enters continuously a well-mixed reactor that contains the ionic active phase. The effluent (a mixture of the two liquid phases) leaves the reactor via an overflow into a settler. The separation of the IL and the organic phase occurs rapidly and completely, favored by the difference in density. The IL containing the catalyst is recycled while the product stream is recovered and on line analyzed. 

This IL-based process has been successfully tested in a continuous-flow pilot plant for 2 months. For this pilot-scale trial, the Cu-IL composite catalyst was prepared from industrial-grade chemicals and stored for 8 months before starting operation, to prove its sturdiness to impurities and its stability, as key features determining its suitableness for industrial use. A mixture of a heavy C4 fraction (namely 2-butene) obtained from a commercial refinery was employed as olefin... 

With funds from the Australian National Collaborative Research Inffastmcture Strategy (NCRIS) a continuous flow pilot-scale hydrothermal processing unit became operational at the University of Sydney in 2012. The design of the unit is based on coiled stainless steel tubes submerged into a fluidized sand bath in a plug flow reactor type set-up. 

Iron and molybdenum were determined by standard atomic absorption methods. Pore volume, densities and hardness values were determined by the usual methods used in catalysts characterizatiom Activities and selectivities of the catalysts in the conversion of methanol to formaldehyde were determined in a continuous flow pilot plant described by Karim and Hununadi [8]. Test conditions were reactor temperature 200 to 350°C (473-623 K) pressure, 10 atm (1013 kPa) flow rate, 15.858 cm /s methanol, 5.5% by volume in oxygen. 

---