Warm-up condensate

Keeping track of orphan streams, such as coke drum warm-up condensate, is an unenviable but vital part of the operating engineer s job. The green wax when collected can, after all, be turned into gasoline. 

Warm-up condensate. This often mishandled stream can represent one-... 

FIGURE 2-3 Draining warm-up condensate properly will prevent a foamover. 

The warm-up condensate is collected in the drum shown in Figure 2— 3. Initially, the condensate contains quite a bit of water and, hence, should be charged to FCCU feed tankage. The conradson carbon and metal s content of the condensate is in the range of heavy coker gas oil, and it will make acceptable FCCU feed. 

If the air dewpoint is higher than the water temperature (or more accurately, the surface temperature of the drops), water vapor condenses from the air on the surface of the watet drops. Now the water warms up and the air cools down and at the same time dries up in other words, the cooling tower recovers heat from the outlet air. We will now consider the operation of a cooling tower more closely with the notations of Fig. 4.19. 

Where these valves are used, the time available to warm up the pipe work will be known, as it is set on the valve control. In other cases, details of the start-up procedure must be known so that the time may be estimated. Thus boilers started from cold may be fired for a short time, shut off for a period while temperatures equalize, and then fired again. Boilers may be protected from undue stress by these short bursts of firing, which extend the warm-up time and reduce the rate at which the condensate in the mains must be discharged at the traps. 

A solution of 183 g. (1.10 moles) of triethyl phosphite (Note 1) in 200 ml. of petroleum ether (b.p. 30-60°) is added to a 3-1., three-necked, round-bottomed flask equipped with a mechanical stirrer, a thermometer, a dropping funnel, and an air condenser the open end of the condenser is connected to a drying tube filled with calcium sulfate or calcium chloride. The flask is immersed in a freezing mixture of sodium chloride and ice, and the stirrer is started. When the temperature of the phosphite solution reaches 0°, a solution of 273 g. (1.00 mole) of hexachlorocyclopentadiene (Note 2) in 100 ml. of petroleum ether (b.p. 30-60°) is added through the dropping funnel at such a rate that the temperature remains between 0° and 10°. The addition requires about 4-6 hours. After the addition is complete, the freezing mixture is removed, and the brown, clear solution is allowed to warm up to room temperature. 

The co-condensation reactions described above have led to the formation of interesting new compounds and sometimes very unexpected products. The nature of the products formed for example in the osmium atom experiments indicate high degrees of specificity can be achieved. However, the detailed mechanisms of the co-condensation reactions are not known. It seems most likely that in all cases the initial products formed at the co-condensation temperature are simple ligand-addition products and that the insertion of the metal into the carbon-hydrogen bond occurs at some point during the warming up process. In support of this hypothesis we note the virtual absence of any... 

Let us remember also that cold surfaces adsorb gases if a small leak to atmosphere exists, air will condense on cooled surfaces. If the amount of gas adsorbed is large, during warm up, the pressure in the vacuum space may become very high. A release valve must be therefore present in the system. 

C. 2-Methylmercapto-N-methyl-A 2-pyrroline. 2-MethyImer-capto-N-methyl-A -pyrrolinium iodide (662 g., 2.57 moles) is suspended in 1.25 1. of anhydrous ether in a 4-1. three-necked flask equipped with a mechanical stirrer and a reflux condenser with a segment-shaped paddle. Potassium f-butoxide (448 g., 4.0 moles) is added in one batch to this suspension with vigorous stirring. The mixture warms up a little, and later the solid becomes fine-grained and more mobile as a result of separation of potassium iodide. After being stirred for 1.5 hours at room temperature, the mixture is treated with 1.81. of anhydrous ether and boiled under reflux on a water bath for 5 hours. 

The engine must be warmed up first by running it on gasoline or by heating the cylinder block otherwise all the produced steam will condense immediately on the cold cylinder walls. This happens in my syringe tests. I don t get any pressure rise and the inside walls of the transparent syringe are covered with tiny droplets of condensed water. 

The experimental arrangement consists of a 250 ml three-necked flask equipped with stirrer, double-necked head with reflux condenser and thermometer, and a rubber stopper through which passes a glass rod. 63 g (0.5 mol) of melamine and 150 g of a 40% aqueous formaldehyde solution (2.0 mol) are placed in the flask the aqueous suspension is stirred and adjusted to pH 8.5 by adding a few drops of 20% NaOH.The mixture is heated on a water bath to 80 °C within 5-10 min, with continuous stirring. Complete solution is reached at 70 to 80 °C. During this warm-up period the decrease of pH of the solution must be continually compensated by dropwise addition of 20% NaOH. The stirred solution is now heated to 80 °C at constant pH of 8.5 until the precipitation ratio (see below) reaches 2 2. Next the solution is cooled and filtered from small amounts of insoluble material. 

The maximum pV flow at which the cryopanels are warmed up to T = 20 K in the case of continuous operation, depends on the net refrigerating power of the pump at this temperature and the type of gas. For refrigerator cryopumps and condensable gases the following may be taken as a guide ... 

It was decided to study the system tetrakis (trifluorophosphine) nickel- (0) -ammonia (23) in some detail a smooth reaction was observed when the complex, condensed on excess ammonia at liquid air temperature, was allowed to warm up gradually. Precipitation of colorless crystals, identified as ammonium fluoride in almost stoichiometric amount, based on complete ammonolysis of the phosphorus-fluorine bonds, was observed at temperatures as low as —90° to —80°. Removal of the ammonium fluoride by filtration at temperatures not higher than —50°, and subsequent slow evaporation of the ammonia from the filtrate invariably led to a brown-yellow solid, although a colorless, crystalline material was formed initially. The product was decomposed almost instantaneously by water with precipitation of elemental nickel. Analysis of the hydrolyzate obtained in aqueous hydrochloric acid revealed a nickel-phosphorus-nitrogen atom ratio close to 1 4 4, corresponding to an apparently polymeric condensation product. 

---