Steam cooling water

Utilities These include steam, cooling water, process water, electricity, fuel, compressed air, and refrigeration. The consumption of utilities can be estimated from the material and energy balances for the process, together with the equipment flow sheet. 

Example 1.5. For a binary distillation column (see Fig. 1.6), load disturbance variables might include feed flow rate and feed composition. Reflux, steam, cooling water, distillate, and bottoms flow rates might be the manipulated variables. Controlled variables might be distillate product composition, bottoms product composition, column pressure, base liquid level, and reflux drum liquid level. The uncontrolled variables would include the compositions and temperatures on aU the trays. Note that one physical stream may be considered to contain many variables ... 

System Auxiliary Process Fluid Steam Cooling Water Lubricating Oils ... 

Production Units Production units separate crude oil into different fractions or cuts, upgrade and purify some of these cuts, and convert heavy fractions to light, more useful fractions. This area also includes the utilities which provide the refinery with fuel, flaring capability, electricity, steam, cooling water, fire water, sweet water, compressed air, nitrogen, and so on, all of which are necessary for the safe operation of the refinery. 

Auxiliary process fluid Steam Cooling water ... 

Utilities include the costs of electricity, generating steam, cooling water etc., and emphasises the importance of good equipment and efficient processing and energy-audits for energy conservation and consequent financial savings. 

Variable costs raw material and utilities (electrical energy, steam, cooling water, etc.), overhead (if calculated related to product volume, which is assumed in the example). 

In this system, steam, cooling water, and steam condensate operate and sustain the three subsystems. The state variables of each flow, that is, temperature, pressure, and composition are shown in Table I together with the flow rate. 

Process utilities are fuel, steam, cooling water, chilled water, brines, electricity and refrigeration. Prices on transactional basis are lower. Specify limitations in supply. 

Step 2. This process has 14 control degrees of freedom. They include fresh feed valve DIB column steam, cooling water, reflux, distillate, and bottoms valves purge column steam, cooling water, reflux, distillate, and bottoms valves furnace fuel valve flooded condenser cooling water valve and DIB column feed valve. 

This operating margin mnst cover all charges, such as eqnipment depreciation, and the cost of manpower, and ntilities (power, steam, cooling water, compressed air, etc.). Raw materials of good purity and qnality command a reasonable price in the marketplace. 

Information on the conditions, availability, and price of utility services such as fuel (gas), steam, cooling water, process air, process water, and electricity, that will be needed to run the process. 

Utilities— fuel burned in process heaters, steam, cooling water, electricity, raw water, instrument air, nitrogen, and other services brought in from elsewhere on the site ... 

Many of the offsite items are designed as packaged plants or systems that are purchased from specialized suppliers. In some cases, the supplier may even offer an over-the fence contract, in which the supplier builds, owns, and operates the offsite plant and contracts to supply the site with the desired utility stream or service. Over-the-fence contracts are widely used for industrial gases such as nitrogen, oxygen, and hydrogen, and most plants also import electricity from the local utility company. Over-the-fence contracts for steam, cooling water, and effluent treatment are less common, but are sometimes used in smaller plants or where several companies share a site. 

Although there are several different commercial technologies in use the economic information described below relates only to the liquid phase technology. The cost of EB production consists of three main components raw materials, utilities, and the fixed cost associated with the plant. The cost of utilities includes fuel, electricity, steam, cooling water, catalyst, and chemical costs required to operate the plant. Ethylbenzene plants typically have a small net negative utilities cost because the credit value of steam generated usually exceeds the cost of other utilities used throughout the plant. 

The cost of styrene production can be broken down into three main components raw materials, utilities, and the fixed cost associated with the plant. The utilities cost includes fuel, electricity, steam, cooling water, catalyst, and chemical costs required to... 

Qeneral plant installations steam, cooling water, vacuum... 

In some cases, it may be desirable to estimate the prices of utilities, such as steam, cooling water, and electricity, during process creation. Here also, appropriate prices can be obtained from local utility companies. As a start, however, values are often tabulated, as provided in Table 17.1. 

Utilities (type and availability) - Electric power - Steam - Cooling water - Cooling brine - Compressed air, instnunent air - Inert gas... 

The MINLP model is using additional annual profit of heat and power integration criterions. The additional annual income of integration sums up the additional savings of fuel, 5 bar steam, 8 bar steam, cooling water and 37 bar steam and electricity production. 

The feedstock available (natural gas, residual gases from refineries, LPG (Liquefied Petroleum Gas), naphtha, heavy oils, distillation residues, pitch, coal, carbon dioxide, oxygen) and process utilities (steam, cooling water,...). 

Most often, utilities do not direcdy contact process streams. Instead, they exchange heat energy (fuel gas, steam, cooling water, and boiler feed water) in equipment such as heat exchangers and process heaters, or they supply work (electric power or steam) to pimps, conpressors, and other rotating equipment. In most cases, the flowrate can be found either by inspection or by doing a sinple heat balance around the equipment. 

Fluid to be handled Identify the fluid to be handled is a process fluid or a utility fluid (such as steam, cooling water). Next identify it is single phase flow (vapor or liquid only), two phase flow, gravity flow, oratimy flow. Also check whether the fluid is Newtonian fluid or not. For Newtonian fluid, its viscosity is constant at fixed operating conditions (temperature and pressure). This chapter vvdit discuss line size for Newtonian fluid only. 

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