Precautions for installing the device in water circulation systems

The water-gas combined operation conditions should ideally mimic the design conditions; it is best if operating parameters such as gas phase pressure and temperature remain consistent. After operating for a while, many unexpected problems often arise, and these are precisely the key aspects to focus on in water-gas combined operation. As for cleaning and filtering, just follow the steps.

Hydrotransport is the most basic method, but it is not decisive; as the oil enters the facility, both temperature and pressure change throughout the startup process. The viscosity of oil is much higher than that of water, which is why diesel transport is also essential during the startup phase after a new facility is built.

Precautions for using the device in water circulation systems: 1. Install a filter screen at the pump inlet (60-mesh is sufficient); if any abnormalities are detected during operation, contact the maintenance mechanic promptly to make the necessary adjustments； ⒉The control valves need to be put into operation; their shortcomings during operation should be identified and addressed ； ⒊During combined transportation, it is necessary to calibrate using the indoor and outdoor level gauges to lay a solid foundation for normal production ； ⒋The operation period should ideally be over 15 days, to facilitate the identification of potential issues with the equipment, improve the skills of the team, and lay a solid foundation for smooth operations in the future.

This section describes the entire operating procedure for the device’s water circulation. Water circulation should continue before rotating all personnel involved, so that they can become familiar with the units they are responsible for. Water circulation operations should include all utility systems, including DW and PA. The reason for using DW during water circulation operations is: — The water will be very clean to keep the equipment clean. — The chlorine content should be less than 30 wtppm to prevent corrosion of stainless steel equipment and pipes. For safety reasons, PA is used in place of N2. — The total amount of DW required is approximately 500 m3. — The required maximum PA flow rate is 200 Nm3/hr ； Before starting the water operation, DW should be stored in the plant’s storage tank to reduce the time required to receive DW from outside the facility. The flow of other utilities is below normal operating levels. 6.3.2 Purpose of water operation (1) The process simulation using DW to simulate process conditions makes use of all utility systems, such as steam, cooling water, instrumentation, air, etc. (2) Familiarize the employees with the device; have the operators prepare and carry out the water circulation, and complete as many water circulation cycles as possible in accordance with the startup instructions for this unit. The entire device is controlled by the PI diagram, and the loop should be as large as possible. (3) The regulating or monitoring instruments ensure the proper operation of the internal interlock system and alarm system of the control valve. (4) Check the mechanical installation and perform further airtightness tests; ensure that safety valves, vent valves, and check valves are properly installed. The pump, mixer, blower, etc. must be tested. If possible, tighten the flange bolts after raising the heater’s temperature to the normal operating value. All connection points should be checked for leaks. The relevant equipment must undergo pressure and vacuum testing. Note: All liquids will be drained during pre-startup and water circulation. During water circulation, the heat tracing/jacket system must be shut down. 6.3.3 Operations before water circulation Before starting the water flow, the following operations should be carried out: — Flush the pipes — Clean the interior of the equipment — Clean and reinstall the filters — Install baffle rings inside — Restore the instruments/pressure safety devices — Check for airtightness — Test the vacuum level. When starting the water flow, the catalyst should be loaded into the reactor through the side lines, in order to prevent materials from clogging the pores in the reactor’s catalyst screen. 6.3.4 Prepare to ensure that the following operations are completed: — The measuring and control equipment must be checked to guarantee proper operation. — All valves and control valves must be in the closed position, all control devices must be set to manual mode, CW/TCW/CCW must be introduced into the coolers and condensers of all units, and some temporary facilities must be installed for water operation: — Filter screens (40 mesh) at the inlets of nozzles and mechanical seals. — Temporary components for cartridge filters. — The temporary pipe indicated in the water circulation procedure (to be prepared by the buyer). The specifications for the temporary components of the filter cartridge are as follows: Component material: Cotton yarn. Filter rating: 25μm (specified for all except F-011A/B); 5μm (specified for F-011A/B). 6.3.5 Water operation (1) Operation mode: Water operation is carried out unit by unit. These units should be made as close as possible to actual operation. (1) Special attention should be paid to: a. Theoretically, all equipment should be inspected while the water is in flow, but there are some devices that cannot be inspected, such as the pressure difference meters in reactors containing catalysts; these devices should be checked during the operational phase of the process. b. Due to the differences in density and design of the fluid (water) handled during water operation, special attention should be paid to factors such as different shutdown pressures during operation. c. Before starting the pump in each unit, water should be supplied to the mechanical seal of the pump at the flow rate described in 7.3.5. d. Although the CW used to cool the bearings is not necessary to be supplied to the pump machines listed below, it is better to do so in accordance with the regulations for simulating normal operation. 6.3.6 Restoration and Cleaning (1) Remove the conical filter at the pump inlet and install a gasket. (2) After cleaning, reinstall the filters listed below: — Y-type filter — Conical filter upstream of the vacuum system. — After the unit is put into operation, the above-mentioned filters should be installed during the one-year period of normal operation. — R upstream cone filter: A cone filter (40 mesh) is installed at the inlet of R. — Wedge filter (0.1mm) on the R discharge line. Install wedge filters on R’s discharge pipeline. (3) Remove the temporary components of the cartridge filters, and install the components listed on the schedule for each filter. (1) Remove other temporary facilities used for water circulation. (2) After the water is circulated, clean the storage tank.

Everyone has spoken very well; there seems to be one issue that hasn’t been mentioned, and that is the need to strictly control the CL ions in water for pipelines made from high-pressure special steels such as chromium and molybdenum. Generally, the level of these ions should be below a few PPM – the lower, the better!

This is equivalent to the operation of the device under load; pay attention to the operation of the pumps as well as the calibration of the instruments