Pump, variable-speed gear

Sodium hydroxide or other neutralising agents, water and other solvents if required are normally added to the neutralisation loop using metering pumps. Variable-speed gear pumps controlled by mass-flow meter-based systems can be used. 

In 1840 a hydrauHc power network, which involved large reciprocating pumps that were driven by steam engines, suppHed fluid power to London. However, concurrent technology in steam (qv) turbines and the electric generators outmoded such networks until hydrauHc systems were improved with the use of rotary pumps and oil. The rotary piston pump marked the transition from use of water to oil as the hydrauHc fluid (4). The use of vacuum-distilled, refined mineral oils were instmmental in the success of rotary axial piston pumps and motors such as the Waterbury variable speed gear... 

The schematic of the experimental apparatus is shown in Fig. 1. It consists of a supply tank, variable speed gear pump, filter, preheater, flowmeter, test section, and return tank. The supply tank is provided with a preheater (1.5 kW). The return tank is provided with cooling coils and is mounted above the supply tank and is coimected to the supply tank by a valve. An inline filter and an additional inline preheater (700 W) are provided downstream of the pump. The liquid flow rate is measured using the flowmeter provided upstream of the test section. 

Control of the level in the acid/gas separator ensures an effective seal between the liquid handling parts of the sulphonation plant and the exhaust gas treatment section. Several methods can be used, but the one which minimizes the hold-up and residence time distribution of acids, and consequently dioxane formation during ether sulphate manufacture is based on control of a variable speed gear pump. 

After the SO converter has stabilized, the 6—7% SO gas stream can be further diluted with dry air, I, to provide the SO reaction gas at a prescribed concentration, ca 4 vol % for LAB sulfonation and ca 2.5% for alcohol ethoxylate sulfation. The molten sulfur is accurately measured and controlled by mass flow meters. The organic feedstock is also accurately controlled by mass flow meters and a variable speed-driven gear pump. The high velocity SO reaction gas and organic feedstock are introduced into the top of the sulfonation reactor,, in cocurrent downward flow where the reaction product and gas are separated in a cyclone separator, K, then pumped to a cooler, L, and circulated back into a quench cooling reservoir at the base of the reactor, unique to Chemithon concentric reactor systems. The gas stream from the cyclone separator, M, is sent to an electrostatic precipitator (ESP), N, which removes entrained acidic organics, and then sent to the packed tower, H, where SO2 and any SO traces are adsorbed in a dilute NaOH solution and finally vented, O. Even a 99% conversion of SO2 to SO contributes ca 500 ppm SO2 to the effluent gas. 

In recent years, the addition of tallow has moved directly to dairy and beef feed lots. Small, heated, insulated tanks have been developed to receive and hold fat shipments (Figure 7). As described earlier, beef tallow is the most compatible fat for ruminants. It may be sprayed or flowed, at 2-3% of dry matter onto rations of chopped hay, other roughages, grains, or concentrates while in the mixer, or top-dressed on hay or other forages. Feed mixing operations like these require a positive displacement pump, like a Moyno or gear pump with variable-speed drive set to deliver a known amount of fat within a specific time period. As an alternative, mixers in feed mills can be mounted on load cells and equipped with controllers to stop the flow of fat when the desired weight has been added. 

Pump speed too low. Options Install a gear reducer or variable speed drive to increase pump speed. Install motor with higher rpm. 

Pump speed too high. Options Install gear reducer or variable speed drive. Install motor with lower rpm (also reduces discharge head of pump). 

In the previous secdon, we explained the concept of linear speed and acceleradon. Now we will consider variables that define angular motion. Rotadonal modon is also quite common in engineering applicadons. Examples of et jneering components with rotadonal modon include shafts, wheels, gears, drills, pulleys, fim or pump impellets, helicopter blades, hard drives, CD drives. Zip drives, and so on. 

Polymer processes, whether batch or continuous, rarely run under stable equilibrium conditions. However, in order to operate such processes safely and in order to set the characteristics of the products optimally, a set of process manipulated variables must be kept constant or systematically modified over the duration of the reaction or in the course of the various reaction steps. The main process variables of this type are temperature, pressure, concentration, amount, flow, and level. Speeds (agitator, gear pumps, extruders), power input and viscosity can be of substantial importance also. 

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