Steps to start up the gasifier

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Steps for driving 1: Verification of the initial driving condition. 1.1 After the system has been installed or repaired, verify each item in accordance with the requirements specified in the installation contract or repair plan; check the quality of the installation and the extent of completion. The acceptance procedures shall be carried out based on the delivery acceptance report. .1.2 Clean any debris and dust accumulated inside the equipment, seal the equipment’s manholes, and have the on-site inspectors fill out the inspection report form. .1.3 For pipeline cleaning and purging, refer to the cleaning and purging plan. After the cleaning and purging are completed successfully, the supervisor, on-site responsible personnel, and project manager shall conduct inspections and confirmations, and fill out the cleaning and purging acceptance form ； .1.4 After confirming that the equipment manholes and pipe flanges are properly sealed and tightened, and after the installation of the equipment pipes is completed and the handover procedures are carried out, notify the maintenance staff to check each flange gasket and bolt to ensure they meet the requirements, and then tighten the bolts ； .1.5 The system pressure test and airtightness test shall be carried out in accordance with the corresponding test plans; once the tests are successful, they shall be inspected and confirmed by the supervision personnel, on-site supervisors, and project managers, who will then fill out the forms confirming that the pressure and airtightness requirements have been met ； .1.6 Conduct a single-unit test run of the system; once the equipment is installed and the mechanical, electrical, and instrumentation systems are ready for operation, if there are no issues during the four-hour single-unit test run, fill out the single-unit test record and file it ； .1.7 After conducting the opening and closing tests on the instrument valves, it was confirmed that their operation is stable, they close properly in place, and they meet the design requirements; debugging records have been kept ； .1.8 Conduct interlock and alarm testing on the instrument-controlled valves to ensure that they meet the requirements regarding response time and programmed timing; simulate interlock conditions to verify the reliability of the interlock function, and keep proper records of the testing ； .1.9 Contact relevant positions and workshops to confirm that the conditions for starting up are met; reach out to various functional departments to verify that these conditions are satisfied, submit an application to start up the system and obtain approval, and prepare the necessary coordination documents for startup ； .1.10 The site shall be cleaned thoroughly, roads kept clear, all scaffolding removed, safety passages unobstructed, and a driving warning area established ； .1.11 Organize personnel from various departments and functional units to conduct a comprehensive pre-start inspection to ensure that all conditions for starting up are met ； .1.12 Contact the dispatch team to confirm that all utility conditions are met, issue the relevant tickets for shutting down or starting up the utilities, deliver all materials into the designated area, and make preparations for startup. 2 Preparatory work before starting up the gasification furnace. 2.1 Verification of the valve status before starting up the gasification furnace: Before starting it, the shift leader assigns a dedicated person to check each valve using the valve status verification sheet; once the checks are completed, signatures are made. These documents are then submitted to the control room, and only after the technical staff and workshop supervisor have signed to confirm the valve status can feeding begin ； 2.2 Before starting up the gasification furnace, the shift leader shall contact the maintenance staff to reset the blind flanges; all temporary blind flanges have been removed. – Before resetting, a work permit for removing and installing blind flanges must be obtained (outside operations). The work permit is filled out by technical personnel who outline the safety measures, which are then reviewed by the safety officer and approved by the workshop supervisor. Only after ensuring that all safety measures are in place can the work proceed <outside operations>. The safety officer, technical personnel, and workshop supervisor check to confirm that these safety measures have been properly implemented. 2.3 Water supply to the cooling ring of the gasification furnace: The water circulation process is as follows: RW→HV1307→R1301→V1305→V1309→P1303→V1410→V1411→P1403 ↑_________________________________________________↓ (Outside operations) – Close the graywater supply valve LV1306 and its upstream and downstream valves ； (Outdoor operation) — Open the front and rear valves of HV1307 ； (Internal operation) — Shut down the chilled water addition valve FV1315 ； (Outdoor operations) — Verify that the main valve for feeding water to the scrubber tower in the graywater heater E1401 is closed, and that the blind flange is in the correct orientation ； (Outdoor operations) — The main valve for feeding water into the scrubber tower via the high-pressure ash water pump P1406 is closed, and a blind flange is used to reverse the flow direction ； (Outdoor operations) – Reverse the flow at the blind flange in front of vaporizer water seal tank V1305; open the front valve ； (Outdoor operation) — FV1304 and the upstream valve are in closed state ； —Open the water valve once ； —Adjust the opening degree of valve HV1307 to ensure that the raw water flow rate at FT1316 is above 35 m3/h ； —Close slag lock valve KV1302 ； (Outdoor operation) — When the level of LT1301\02 can be seen, check whether the overflow from V1305 is normal ； —When the level of sludge tank V1309 reaches 50%, start P1303 to send it to the sedimentation tank V1410 ； —Set the LT1305 to 50% automatic mode ； (Outdoor operation) — Once the sedimentation tank is full, the raw water overflows into the graywater tank V1411 ； —When the liquid level in the graywater tank V1411 reaches 50%, start the low-pressure graywater pump P1403 to supply water to the gasification unit ； (Outdoor operation) — Add water to the gasification furnace, switching from raw water to P1403 water ； 〈External Operation〉 — When shutting off water, close the raw water valve and open the low-pressure graywater valve simultaneously to ensure that the gasification furnace does not run out of water (referencing the furnace drying process) ； .2.4 Gasifier water distribution test <Field operation> — The gasifier water distribution test must be carried out before heating up the gasifier; ensure that the negative pressure in the gasifier is normal during this test ； —Open the upstream and downstream valves of the water supply valve LV1306 in the washing tower for outdoor operations ； —Turn off HV1307 ； —Adjust the LV1306 valve position and add water to the scrubber tower to 80% level ； (Outdoor operation) — Confirm that the valves before and after FV1315 are open, and the valves before and after filter V1304 are open ； 〈External Operations〉—The personnel responsible for checking water distribution wear raincoats and carry lighting devices; they enter the combustion chamber via the downcomer, going up the ladder from the quenching chamber ； 〈External Operation〉—Once the inspector is ready, notify the external operation personnel to start the quench water pump P1304 ； —Adjust the opening of FV1315 to control the water supply to the quench ring; alternatively, the operator can control the water volume or motor current by operating the outlet valve of P1304 ； —Check the water distribution in the quenching ring at water flow rates of 30 m3/h and 160 m3/h respectively ； 〈External Operation〉 — For water distribution, it is required that the water film be uniform, with no flow deviation, and that there be no \"dry zones\" in the downcomer. .2.5 Ignition and heating of the vaporizer – Connect to the liquefied gas station’s pipeline to perform nitrogen purging ； —Open the main liquefied gas valve of the farthest gasifier burner, inform the liquefied gas station to supply nitrogen, and have a dedicated person monitor the process ； (Outdoor operation) — 15 minutes after nitrogen begins to be emitted, samples are taken for analysis; the condition is considered satisfactory when O2 is ≤0.5%. Subsequently, the liquefied gas pipelines of the other two vaporization units are replaced in the same manner ； (Outdoor operations) — Once the liquefied gas pipeline replacement is complete, close all valves of the liquefied gas burners ； —Notify the liquefied gas station to deliver liquefied gas ； —Activate the steam extraction pipeline and open the main valve of the extractor ； —Slightly open the steam suction bypass shut-off valve to maintain a slight negative pressure in the furnace. —The maintenance staff installed the preheating burner; the liquefied gas pipeline is connected to the preheating burner via a hose, with no leaks ； —Open the upstream and downstream valves of the FV1324 liquefied gas control valve for outdoor operations ； —Notify the operator to slightly open control valve FV1324 ； —Use an ignition gun to light the preheating burner X1304, and adjust the liquefied gas flow rate, the negative pressure in the furnace, as well as the opening degree of the air valves, so that the negative pressure inside the furnace remains between –10mm and –20mmH2O ； (Internal operation) — During the initial startup, the furnace is heated in accordance with the specified heating curve until it reaches 1100°C (or the specified temperature) ； (Internal operation) — The daily heating rate should be less than 50°C/h ； (Internal operation) — When the gasification furnace is heated to 500°C, if the flow rate of liquefied gas is not sufficient to provide the heat required for heating, diesel can be used instead to achieve this ； —When replacing the diesel gun, close the main liquefied gas valve, then use nitrogen to purge the pipelines of the liquefied gas burner; thereafter, the operator on site closes the valve of the liquefied gas burner ； —Close FV1324 after receiving the external operation notice ； —Pull out the liquefied gas gun and replace it with a diesel atomization gun ； —Adjust the diesel pressure PICA1319 to 0.9 MPa (G) ； —After receiving the notice, slightly open FV1325 ； —Ignite the atomized diesel using a lighter gun ； —Upon receiving the instruction, gradually increase the FV1325 setting, and adjust the diesel flow rate to continue raising the temperature ； Temperature control principle: I. Heating: First increase the volume of the intake gas, then increase the volume of the fuel gas and air flow ； II. Cooling: First reduce the fuel gas flow and air flow, then reduce the intake gas flow. —Replace the normal thermocouple: When the temperature of the vaporization furnace reaches above 800°C, inform the instrumentation staff to replace the heating thermocouple with a normal process thermocouple ； Safety precautions: ① Throughout the heating period, the temperature of the gas exiting the quench chamber must not exceed 252°C; if necessary, increase the water flow rate of FT1316, but be sure to keep the liquid level in the vaporizer below that of the downcomer ； ② Once the flame is extinguished, immediately close the liquefied gas or diesel shut-off valve, remove the burner, create a negative pressure for 5 minutes, reignite it, and raise the temperature at a rate of less than 50°C/h to the temperature before it went out; then continue raising the temperature according to the heating curve ； ③ There is a significant difference between the temperature inside the furnace and the actual temperature; during the heating process, attention should be paid to the pressure difference at the slag outlet and the temperature at the gas outlet to prevent blockage of the slag outlet ； ④ Raise the temperature to 600°C to start the slag breaker and supply flushing water ； ⑤ When watching the fire, wear a protective mask and pay attention to personal safety. .2.6 Establishing the vacuum flash system: Before feeding material into the gasifier, a vacuum flash system is started in advance to establish a water circulation within this system. The flow path is as follows: V1309 → P1303 → V1404 (upper) → V1404 (lower) → P1402 → V1410 → V1411 → P1403 → R1301 → V1305 → V1309. The heat exchangers E1406A\B, E1407A\B, and E1409A\B are put into operation; the inlet and outlet valves as well as the vent valve of these heat exchangers are opened, while the drain valve is closed. Once a steady water flow is established, the vent valve is closed ； —Open the valve from the slag tank to the vacuum flash drum ； —Open the valve from the sludge tank pump to vacuum flash evaporation, and close the valve leading to the clarification tank ； —Open the valves before and after control valve LV04; close the backwash and bypass valves ； —When the top tower liquid level LT04 reaches 50%, LV04 switches to automatic mode ； —When LT reaches 50%, start the clarification tank feed pump to send water to the clarification tank; the operator shall set LV05 to automatic mode ； —Start the vacuum pump in accordance with the procedures ； —Adjust the vacuum pressure control valve to maintain the pressure in the upper section of the vacuum flasher at around –0.07 MPA ； —Activate the vacuum extractor to maintain the inlet pressure at —0.089 MPa ； —When the liquid level in the vacuum flash condensate separation tank reaches 50%, close the bypass valve and the backwash valve, and open the valves before and after LV06 ； —Put LV06 in automatic mode ； —When the liquid level in the separation tank of the vacuum condensate tank reaches 50%, start the vacuum condensate pump to send the condensate to the clarification tank ； —Set LV07 to automatic mode ；