Equipment cleaning isolation

Process "simulation. This technique is applied to equipment that is easily fouled and for which spare parallel units are provided. The fouled equipment s isolated, drained of process fluid, and filled with the cleaning solution the process operation is then simulated, thereby cleaning the equipment. An example of this route is the removal of iron oxide and copper deposits from high-pressure steam generators, using ammoniated ethylenediaminetetraace-tic acid (EDTA) solution. 

Table 1 shows the hierarchical task analysis of P.TW system procedure in the studied petrochemical plant. As it can be seen, 11 main tasks and 4 subtasks were identified in HTA process. Task No. 3 (Inspecting the workplace and complete the checklist section in the permit) had 4 subtask including venting process equipments from flammable and toxic materials, lock out and tag out the electrical equipment, cleaning the work area from flammable material and isolation of process equipment. 

Storage tanks should be designed in accordance with the ASME code for unfited pressure vessels. AH-welded constmction is recommended. Ethylene oxide storage tanks should be electrically grounded, isolated from potential fire hazards, and equipped with pressure rehef devices. New equipment should be cleaned of iron oxide and immediately purged with inert gas. 

Simple strainers remove gross materials. These should not normally occur in public supply, but strainers are sometimes fitted to protect sensitive equipment or processes against breaks in the main, etc. The commonest form contains a stainless-steel wedge wire screen and is piped with a bypass so that the screen element can be isolated and removed for cleaning when necessary. If the load on the filter makes this kind of cleaning burdensome a self-flushing filter can be used. These can incorporate strainer elements down to 50 pm. 

Before carrying out any inspections or maintenance procedures on belt drives, make sure they are not in operation. Equipment operators should electrically isolate the drive system and lock-out and tag the machine that is to undergo maintenance. Once this precaution has been taken, the belts and pulleys can be removed from the machine for inspection, cleaning, and repair. 

Cleaning, Disinfecting Equipment with Pneumonic Plague (The same series of isolation controls as for bubonic plague). 

If non-contact, water cooled condensers are used, water pollution problems should be minimal. Except for cooling, the only other source of water contamination is water used in washing the plant floors and equipment. Oil spills may occur, and should be isolated, contained and cleaned up without contaminating the waste water. 

Equipment in the laboratory that comes into direct contact with a potent compound requires thorough decontamination before it can be removed from the laboratory. Some equipment cannot be adequately cleaned and must be disposed of as hazardous waste. For example, it was found that cooling fans on pieces of equipment (e.g., Endeavor Hydrogenator, HPLC systems) had spread trace levels of contamination throughout the equipment. This equipment could not be cleaned to an acceptable level and therefore had to be disposed of as hazardous waste. The use of isolators or containment laboratories, which is discussed in the next section, is an alternative approach that addresses these issues. 

Isolators should have sufficient service port penetrations to allow as much equipment to be placed outside of the isolator as possible. Traditionally control boxes, chillers, keypads, and printers were placed as close to the analytical instrumentation being used as possible. The amount of equipment in direct contact with the samples should be minimized. If equipment needs to be placed in the isolators, the only way to remove that equipment later is to prove that the equipment has been cleaned to acceptable levels by swab testing. Based on experience, this cleaning is difficult to accomplish and in many cases the equipment needs to be considered contaminated and discarded if there is a need to remove it from the isolators. 

Additional needed process equipment was evaluated, selected, purchased, and set up. Automation opportunities were defined, and process control instruments were tested, purchased, and installed. An existing clean (HEPA-filtered) area was upgraded for the final isolation of the dilevalol hydrochloride made in New lersey—this was needed to serve the requirements for the parenteral dosage form. 

Should the economics of the above-described new process favor a switch from the present AIC process (see Case Study 2) to one based on dihydrohypoxanthine new investment might be justified in new production equipment.81 A switch to the microwave option versus the conventional heating option would depend on the outcome of process optimization work on both. If a rapid clean reaction in near-quantitative yield were realized by optimizing the microwave conditions, then it would prove worthwhile to engineer a simple continuous flow reactor for further development work. The case in favor of adopting the microwave-assisted process would be further enhanced if the solution from the microwave reactor could be used directly in the next process step (thus eliminating the need for isolation equipment). 

This chapter covers examples of system modifications made to prepare for maintenance. Each unwise modification created equipment damage. These incidents were simple changes intended to isolate, protect, clean, or clear equipment, and the methods chosen created problems. In some cases equipment was subjected to partial vacuum or positive pressure beyond the tolerable design limits. 

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