B1 Project Summary (English) PDF

1\. Outline 2\. Towers, tanks, and drums \(1) Vent gas condensation 1\. E-251 is \"BJ VENT GAS COOLER\" 2\. E-252 is \"VENT GAS EXCHANGER\" 3\. E-253 is \"VENT GAS/SILANE CHILLER\" 4\. D-2531 is \"CHLOROSILANE SURGE DRUM\" \(2) Compression \(3) Adsorption system 1\. T-260A, B, C, D, E, and...

1\. Outline 2\. Towers, tanks, and drums \(1) Vent gas condensation 1\. E-251 is \"BJ VENT GAS COOLER\" 2\. E-252 is \"VENT GAS EXCHANGER\" 3\. E-253 is \"VENT GAS/SILANE CHILLER\" 4\. D-2531 is \"CHLOROSILANE SURGE DRUM\" \(2) Compression \(3) Adsorption system 1\. T-260A, B, C, D, E, and F \"ADSORBER\" Recovery of gas from the reactor vent gas and FL-2601 A, B, C, and D is supplied to the E-251. Reactor vent gas is a gas of unreacted BJ, and Recovery of gas from FL-2601 A, B, C, and D is H2 was removed by activated carbon of T-260A, B, C, D, E, and F the HCL. E-251 is a TW heat exchanger, cools to approximate 40 °C from 310 °C the temperature of the vent gas is supplied For the fixed tube sheet heat exchanger, the air layer formed over the upper shell could cause a phenomenon such as cracking in the surface of the tube sheet. To prevent such a phenomenon, feed TW by opening the shell air vent valve. Spill back will adjust the pressure of the D-2541, and maintain the efficiency of heat transfer and clean the tube of E-252 with spill back H2 gas. E-252 is thermal recovery heat exchanger, cools the recovery gas to temperature 34 °C in the vent gas of D-2531. E-253 is cools the vent gas furthermore using MOH as a refrigerant so that chlorosilane is liquefied and separated. E-251, E-252 and E-253 are approximate 91% of the chlorosilane to condense in the reactor vent gas. The D-2531 chlorosilane surge drum recovers the liquefied chlorosilane. The recovered liquid is pumped to the T-258 HCL stripping tower. Vortex breaker is to prevent the occurrence of vortex when the pump is sucking the liquid. P-2531A and B is a pump to feeding the STC from D-2531 to T-258, and then operate one among P-2531A and B while putting the remainder on standby. The suction pipe of P-2531A and B has the bucket strainer. Close the connection valve on the suction pipe of P-2531A and B, SR-2531A is switched to the strainer dedicated to P-2531A. P-2531A and B is starts automatically of pump. The pump of standby starts automatically to continue stable operation if pump of run is stops. Reverse circulation piping will circulate the liquid to D-2531 so as not to accumulate the vaporized gas is the reverse inside of P-2531A and B. TC25411 is adjusted to 5 °C a suction temperature of CP-254A, B, C, and D. If the thermal efficiency of the E-252 is high, the temperature of CP-254A, B, C, and D is increased; to supply gas to the D-2541 is TC25411. Compression efficiency is reduced with increasing suction temperature of CP-254A, B, C, and D. However, the loss of thermal efficiency and piping corrosion caused by condensation happens when the suction temperature is reduced, and then adjusted to 5 °C. The automatic replacement is an operation to replace H~2~ and STC with N~2~ in devices, equipment, and their auxiliary pipes. The automatic replacement, there is \"Air-N2 replacement\" and \"N2-H2 replacement\" and \"STC-N2 replacement\". One of the purposes of replacing the air with N~2~ is to prevent dew condensation and generation of HCl from the chemical reaction of silane gas and the air inside the devices, equipment, and their auxiliary pipes. Replacing air with N~2~ also prevent corrosion of pipes and contamination of products with impurities. In addition, as for the devices, equipment, and their auxiliary pipes that handle flammable gases, elimination of air helps to prevent ignition and explosion caused by a chemical reaction with flammable gas. The purpose of replacing N~2~ with H~2~ is to prevent a solution of N~2~ from entering products and to accelerate chemical reactions by increasing the H~2~ concentration. One of the purposes of replacing H~2~ with N~2~ is to prevent ignition and explosion caused by chemical reactions by eliminating flammable gas contained in devices, equipment, and their auxiliary pipes. One of the purposes of replacing TCS/STC with N~2~ is to prevent generation of HCl and corrosion of pipes caused by chemical reactions by eliminating TCS/STC gas contained in devices, equipment, and their auxiliary pipes. Additionally, the odor of TCS/STC is eliminated from the devices, equipment, and their auxiliary pipes by this operation. The D-2541 is a suction drum of CP-254A, B, C, and D. If the chlorosilanes in gas has been condensed, check the level gauge. The D-2541 pressure is 0.5MPa and Low, chlorosilane is considered difficult to condense. The CP-254A, B, C, and D are compressor of gas. Operate three among CP-254A, B, C, and D while putting the remainder on standby. One Capacity of the CP-254A, B, C, and D is 10640Nm3 / h, and 1.41MPa to increasing the pressure. HC2543A-3 is Spill back of CP-254A. The discharge pressure of the CP-254A is adjusted in HC2543A-3. When running the CP-254A will stop spill back by close the HC2543A-3. The D-2542 is discharge drum of the CP-254A, B, C, and D. If the chlorosilanes in gas has been condensed, discharge liquid stored in D-2542 to D-2531. PC2541 is adjusted to 0.43MPa in the pressure control valve of D-2541. The CP-254A, B, C, and D is reciprocating compressors, and the gas introduced into the cylinder by converting the rotary motion of the motor into the reciprocating motion of the piston through the crank shaft and the connecting rod. CPD-2544A and E, CPD-2545A and E is the drum to maintain a constant discharge pressure and suction pressure. CPP-2547A and E is improve the lubricating action to feeding oil to the bearing of the crank room. CPE-2549A is the oil cooler. Distance piece rooms and ground part, to be purged with N2 and H2 as not to degrade the lubricating oil flowing into the crank room side of the process gas. H2 and N2 were purged distance piece rooms and the ground part is supplied to DG6. Purge the gland packing part of the first room of CP-254A by feeding H~2~, to prevent gas leakage from the gland packing part of the first room to the first room of the distance piece of equipment. Pressure of the gland packing part will be the pressure of DG6. Increase the pressure in the first and second rooms of the distance piece of equipment by purging the rooms with N~2~, so that the gas does not flow from the gland packing part of the first room into the crank room. Adjust and control the pressure in the first and second rooms of the distance piece of equipment, at 40 kPa. Increase the pressure on the wiper rings by purging with N2. Do this to prevent gas entry from the second room of the distance piece of equipment into the crank room, as well as to prevent oil leakage from the crank room to the second room of the distance piece of equipment. Adjust and control the pressure on the wiper rings, at 50 kPa. T-256 is a HCL absorption tower filled with random packing materials as well as a packed tower circulating silane liquid chilled to -40 °C. The vent gas from the reactor in the BJ1 process is compressed in CP-254A, B, C, and, D and fed to the bottom of T-256. The vent gas containing HCL countercurrently contacts the silane liquid flowing down inside the tower of T-256 where more than 98 % of the HCL within the vent gas is absorbed in the silane liquid. HCL is a chemical equilibrium that is easily absorbed by water; however, it requires that the circulation volume of the silane liquid be more than twenty times higher. Thus, in T-256, approximately 150 m^3^/h of the silane liquid needs to be circulated. The bottom liquid from T-256 containing high density of HCL shall be fed to the T-258 HCL stripping tower to vaporize and remove HCL contained in the silane liquid. E-255A and B is a thermal recovery heat exchanger, cools to approximate -22 °C feeding gas to the T-256 in the feeding gas to the adsorber tower. T-256 is HCL absorber tower, and Pressure is 1.41MPa. T-256 is absorbed by the STC in the feeding gas of HCL to circulate the STC. Inside the T-256 is a pole ring of random packing will have been installed. Paul Ring is the contact efficiency becomes higher STC and HCL, HCL will be well absorbed. HCL in the feeding gas to T-256, and then absorbed into the STC for more than 98%. Therefore HCL in the feeding gas to the adsorber tower will be the extent 0.1mol%. FC25801 is the bottom liquid of T-256 to feeding STC to T-258. FC25801 is the feed rate control valve to feeding bottom liquid of T-256 to T-258, and then to adjust to approximately 150 m^3^/h of the silane liquid to be circulated in T-256. LC2580 is adjusted to 50 % in the level control valve of T-258, and then the Bottom liquid of T-258 to feeding STC to top of T-256. This is known as cross circulation of STC to feeding STC for each of the T-258 and T-256. Liquid of each of T-258 and T-256, the heat exchange is E-257A, B, C and D. The feeding STC is cools to -20 °C in E-257A, B, C and D to the T-256 from T-258, because it is high temperature. E-2561 is liquid chiller to cool the STC in R507A. LC2561 is adjusted to 50 % in the level control valve of E-2561. E-2561 can be cooled to -50 °C the STC is possible. The feeding STC is cools to -40 °C in the E-2561 to consider for thermal efficiency to T-256. The feeding STC to T-256, the absorption of HCL is possible by cooling to -40 °C. If the PV of any of TI25612, TI25613 rises to -30 °C, cross circulation of STC between T-256 and T-258 stops. T-258 is a HCL stripping tower filled with the structured packing materials in the upper and random packing materials in the lower, as well as a packed tower to vaporize and remove HCL contained in the silane liquid fed from T-256. The vaporized silane and HCL are chilled to -40 °C by a cryogenic cooler, and then silane is liquefied and recovered into the D-2585 reflux drum. Meanwhile, HCL gas is fed to the E-259 HCL heater, heated to 10 °C, and then fed to the A1 process. The feed rate of 1.1ST to E-2581 shall be adjusted by the calculation of the theoretical steam flow rate based on the feed rate of the silane liquid to T-258, its temperature, and the tower-bottom temperature, respectively. T-258 is HCL tower, and Pressure is 0.67MPa. T-258 is heating the Liquid to 1.1ST of E-2581, HCL is vaporized has been absorbed into the STC. The T-258 is the structured packing of the upper, and the random packing of the lower will have been installed. STC from the T-256 is rectification a random packing of the lower. Then, the vaporized gas inside T-258 is rectification a structured packing of the upper. The E-2582 is methanol prechiller; the vaporized gas inside T-258 is condensed to cool by E-2582. E-2583 is condenser, and then STC is condensed in R507A. LC2583 is adjusted to 50 % in the level control valve of E-2583. D-2585 is reflux drum. STC is condensed by E-2582 and E-2583, accumulate in the reflux drum. LC2585 is adjusted to 50 % in the level control valve of D-2585. The reflux piping has to u seal piping and check valve, so not to reverse gas from T-258. PC2590 is adjusted to 0.67MPa in the pressure control valve of T-258. D-2585 of the vent gas is H2 and HCL, and then the vent gas is heated to 10 °C in the E-259, and then supplied to the A1 process. TC25904 is adjusted to 10 °C in the Silicon Controlled Rectifier of E-259 to the vent gas. When not in use the vent gas in the A1 process, the neutralization process is supplied to the DG4. E-2581 is reboiler, and then STC is vaporized by heating for 1.1ST. FC2581 is the feed rate control valve of 1.1ST. The ST-E258 is a steam trap, and then 1.1SD is supplied to the D-286. The feed rate of 1.1ST to E-2581 shall be adjusted by the calculation of the theoretical steam flow rate based on the feed rate of the silane liquid to T-258, its temperature of TI25803, and temperature of TI25805, respectively. When increase in the feed rate of STC to T-258, and then temperature of TI25803 and TI25805 is rise, the feed rate of 1.1ST is increased. When decrease in the feed rate of STC to T-258, and then temperature of TI25803 and TI25805 is lowered, the feed rate of 1.1ST is decreased. The E-2584 is bottoms cooler, and then cooled to approximately 40 °C the STC was heated at T-258. E-2584 is to cool the STC to prevent cavitation of P-2581A, B, C and D. also, reducing the load on the E-2561. P-2581A, B, C, and D is a pump to feeding the STC from T-258 to T-256 and D-372, and then operate three among P-2581A, B, C and D while putting the remainder on standby. The suction pipe of P-2581A, B, C, and D has the bucket strainer. Close the connection valve on the suction pipe of P-2581A, B, C, and D, SR-2581A is switched to the strainer dedicated to P-2581A. P-2581A, B, C, and D is starts automatically of pump. The pump of standby starts automatically to continue stable operation if pump of run is stops. Reverse circulation piping will circulate the liquid to T-258 so as not to accumulate the vaporized gas is the reverse inside of P-2581A, B, C, and D. LC2560 is adjusted to 50 % in the level control valve of T-256. HCL and chlorosilanes are removed from H~2~ fed from T-256 by activated carbon in the T-260A, B, C, D, E, and F HCL adsorption towers at an ordinary temperature. In the HCL adsorption tower, H~2~ is fed upward from the bottom of the tower, and then HCL and chlorosilanes are adsorbed by activated carbon that fills the tower. Then, the recycled H~2~ is recovered from the top of the tower. The purity of the recovered H~2~ is 99.9999 %. CO~2~, CO, N~2~, and CH~4~ will not be removed since these are the substances that activated carbon will not adsorb. FL-2601A and B is a filter to remove dirt such as carbon that accompanies of the recovered H2. PC26002 is adjusted to 1.35MPa in the pressure control valve of discharge pipe of adsorber tower. HMH is fed through the coils on the inside and outside of the HCL adsorption tower to heat the tower. HMC is fed to the HCL adsorption tower to cool the tower. HM piping of the HCL adsorption tower, there is the coils on the inside and outside core. Operate HCL adsorption towers on a 5.5 hour shift basis. Always operate one tower to adsorb HCL while the other two standby towers are under purging. The adsorption sequence progresses for every necessary time for the \"Heat & Purge\" process. The purge process consists of decompression, heating, heating & purge, cooling, and compression. "Make up H2" is used for reproduction and pressurization. FC2600A3 is feed rate control valve to H2 of reproduction and pressurization. Step1 Adsorption process of HCL is switched to T-260A from T-260C. Shifts to the \"Adsorb\" process for HCL contained in the H2 that is circulating through the B1 process. T-260A is 5.5 hour, and adsorption. T-260A is operated to adsorb HCL while the other two standby towers are under purging. T-260C after the adsorption step is completed, all valves will be closed. Step2 T-260C will start regeneration of the activated carbon. T-260C shifts to the \"Heat\#1 & Depress\" process, and then T-260C is started decrease the pressure. Then, heating is started to supply HMH to T-260C. To prevent thermal shock from occurring to the HM pipe when switching from HMC to HMH, HMH is fed to the HMC side until the PV of TI2600A8 increases. Step3 T-260C shifts to the \"Heat\#2 & Depress\" process. HMH is switched to HMHR piping from HMCR piping. Step4 T-260C shifts to the \"Heat & Purge\" process. Start feeding purge H2 to T-260C. T-260B is to finish increasing the pressure, and then shifts to the \"standby\" process. T-260B is connected to the discharge valve is opened for H2. Step5 T-260C shifts to the \"Hold\" process. The purge H~2~ discharge valve closes on T-260C. T-260B is connected to the supply valve is opened for H2. Step6 Adsorption process of HCL is switched to T-260B from T-260A. T-260B is 5.5 hour, and adsorption. T-260A will start regeneration of the activated carbon in the same way as T-260C. Step7 T-260C shifts to the \"cool\#1\" process. HM is switched to HMC piping from HMH piping. Step8 T-260C shifts to the \"cool\#2\" process. HMR is switched to HMC piping from HMH piping. Step9 T-260C is to finish increasing the pressure, and then shifts to the \"standby\" process. T-260C is connected to the discharge valve is opened for H2. Step10 T-260C is connected to the supply valve is opened for H2. Step11 Adsorption process of HCL is switched to T-260C from T-260B. T-260C is 5.5 hour, and adsorption. PC260031 is adjusted to 1.3MPa in the pressure control valve of the H~2~ circulation pipe. Pressure of H2 circulation pipe is decreased by feeding H2 to A1 process and the CVD REACTORS, adjust the pressure to supply 1.7H2 is PC260031. Control the PV of PI26003 by adjusting the feed rate of 1.7 H2 fed to the H2 circulation pipe in the B1 process. PC260032 is adjusted to 1.3MPa in the pressure control valve of the H~2~ circulation pipe, and to discharge to DG6 when the pressure was increased than 1.6MPa. PC260033 is adjusted to 1.4MPa in the pressure control valve of the H2 circulation pipe, and to feed to E-251 when the pressure was increased than 1.4MPa. PC260033 is a pressure control valve, which is used only when starting or stopping the B1 process, as well as being a bypass control valve for the H2 feed pipe in the BJ1 process. The pressure of the circulation pipe H2 is usually adjusted by only PC260031. D-284 is HM recovery drum; P-2841 is HM recovery pump. D-284 is a tank to store the HM necessary to feed to D-281. When the amount of HM is decreased, feed HM from an HM drum to D-284 using an air-driven diaphragm pump. D-281 is HM expansion drum. In the he HCL adsorption tower, HM is used as media for heating and cooling to recycle Chlorsorb RL-13. For the recycle operation in the he HCL adsorption tower, HM is repeatedly heated and cooled. The HM expansion drum is a tank to reduce the fluctuation due to the HM expanding and shrinking phenomenon. When the amount of HM in D-281 has decreased, HM shall be pumped from D-284 to adjust the amount in D-281. PC28101 and PC28102 are adjusted to 300kPa in the pressure control valve of D-281. PC2810 is the control of a single instrument, which is split control valve to control the adjustment of two of PC28102 and PC28101. If the pressure of D-281 increases higher than 300 kPa, discharge gas from D-281 into D-284 to decrease the pressure. If the pressure of D-281 decreases lower than 300 kPa, feed 0.85N2 to increase pressure. P-2811A, B and C are a pump to feeding the HMH and HMC from D-281 to the HCL adsorption tower. P-2811B is put on standby for substitution of both P-2811A and C while P-2811A is used as an HMC feed pump and P-2811B and C are used as HMH feed pumps. HM is difficult because the liquid vaporizes, P-2811A, B and C is there is not reverse circulation piping. E-283 is a thermal fluid cooler, and then cool the HMC to 40 °C in TW. E-282A, B, C and D is a thermal fluid electrical heater. TT282B2 is adjusted to 190 °C in the SCR ( Silicon Controlled Rectifier ) of E-282A and B to HMH, and then TT282D2 is adjusted to 190 °C in the SCR of E-282C and D to HMH. E-283 is regeneration cooler, and then cools the in TW. E-262 is regeneration gas exchanger, cools the reproduction H2 to temperature -5 °C in the vent gas of D-2631. E-263 is regeneration chiller, and then E-263 is cools the reproduction H2 furthermore using R507 so that chlorosilane is liquefied and separated. LC2630 is adjusted to 50 % in the level control valve of E-263. The D-2631 west chlorosilane drum recovers the liquefied chlorosilane. The recovered liquid is pumped to D-361. P-2631A, B, C, and D is starts automatically of pump. The pump of standby starts automatically to continue stable operation if pump of run is stops. LC2631 is adjusted to 50 % in the level control valve of D-2631. The vent gas of D-2631 is exhaust, so there is likely to contain contaminants. HCL concentration of the vent gas is lower in 0.6mol%; the neutralization process is supplied to DG6. The evaporator eliminates heat from the object to be cooled that is cooler than the atmosphere as the latent heat of evaporation of the refrigerant. The evaporated refrigerant is compressed to be easily condensed by air or water of normal temperature, and then liquefied by discharging the condensation heat with the condenser. The condensed refrigerant liquid is expanded at a low pressure and low temperature by the expansion valve, and then fed to the evaporator and evaporated again. The repeat of the above-mentioned operation is called a refrigerating cycle. K-291A and B is Refrigerator to compress the R507A. K-291A and B are the 2 stage type screw compressors. In the casing, sets of male and female rotors mesh together, respectively. R-507A gas is extracted from one end of the rotors into the helical screws to decrease the volume of the gas gradually through meshing of the helical screws. Thus, the gas is compressed to the discharge pressure and discharged from the outlet at the other end. To cool the process gasses and liquids, R-507A gas will be liquefied in the condenser and stored in the receiver, then fed to the evaporator. R-507A, used for cooling in the evaporator, vaporizes and then is extracted into the primary inlet of K-291A and B. This equipment is the capacity control slide valve; adjust the load on K-291A. PC2910 is adjusted to 4kPa in the suction pressure control valve of K-291A and B. KP-2911A is lube oil still pump of K-291A. To supply lube oil between the rotors of K-291A, perform smooth rotation of the rotor. The twin rotary compressor compresses the refrigerant while injecting a large amount of oil and eliminates heat by the oil. Therefore the temperature of the discharged gas is lower than that in the case of adiabatic compression. KE-2918A is oil cooler. Adjust the bypass valve on KE-2918A so that the PV of TI-2911A-1 comes within the range of the operation control standards of 45 to 90 °C. KD-2911A is oil separator drum, and then separated oil is supplied to K-291A. Just after starting up K-291A, the operation load is low; therefore, the PV of PC2910 decreases. When the HCP291A is adjusted, HCP291A2 changes in the open direction, and R507A circulates in the suction pipe of K-291A through the hot gas bypass, thus reducing the operational load. The primary suction of the K-291A is supplied from R507A is KE-2915. The secondary suction of the K-291A is supplied from R507A is E-2561, E-2583 and E-263. KE-2912 is a condenser of R507A; KD-2913 is a liquid receiver. R507A will be held in KD-2913 is condensed in KE-2912. KE-2915 is an economizer of R507A. Economizer is vaporized by using R507A, supercooling the R507A supplied to the evaporator, reducing the load of the refrigerator. Controls superheat of the refrigerator of KE-2915 is adjusted to 10 °C. Superheat is the difference between the refrigerant saturation temperatures to convert the pressure transmitter was detected by the temperature and pressure refrigerant gas was detected by measuring sound resistance. This line is to supplied to the secondary suction of K-291A the R507A was evaporated in E-2561, E-2583 and E-263. KD-2916 is suction Liquid separator, and then to separate the liquid in the R507A. D-271A, B, C, D and E is storage drum of TCS. D-271A are equipment that feed and store TCS, which has been refined in T-303 A and B. In a normal state, TCS, which has been refined in T-303 A and B, is be fed to D-272 for storage. However, to adjust the stock in the storage equipment or to analyze it, TCS shall be fed to D-271A for storage. To adjust the stock in D-271A, feeding of TCS from T-303A and B shall be switched to the standby equipment of D-271A in which TCS is not stored. TCS stored in D-271A shall be analyzed to confirm that the TCS analysis value is within the range of the operation control standards. Then TCS shall be fed to D-272. P-2711A is a pump to feeding TCS from D-271A to D-272. P-2711A is not suction strainer, because D-271A is product storage drum of TCS. PC271A is adjusted to 150kPa in the pressure control valve of D-271A. If the pressure of D-271A increases higher, discharge gas from D-271A into DG3 to decrease the pressure. If the pressure of D-271A decreases lower, feed 0.3H~2~ to increase the pressure. D-272 is drum of TCS. D-272 is equipment that feeds and stores TCS that has been refined in T-303A, T-303B, and T-312, respectively. TCS stored in D-272 shall be fed to D-233, D-234, D-235, D-236, D-237, and D-238 in the BJ1 process and used for the deposition of polysilicon. P-2721A and B is a pump to feeding TCS from D-272 to D-233, and then operate one among P-2721A and B while putting the remainder on standby. P-2722 is a pump to feeding TCS from D-272 to reservoir of Other than the D-233. P-2721A and B is not suction strainer, because D-272 is product storage drum of TCS. P-2721A and B has a high capacity, because in the flow orifice of one plate cannot adjust the flow rate of the circulation piping, the flow orifice is attached 2 plate. PC2720 is adjusted to 80kPa in the pressure control valve of D-272. If the pressure of D-272 increases higher, discharge gas from D-272 into DG3 to decrease the pressure. If the pressure of D-272 decreases lower, feed 0.3H~2~ to increase the pressure. D-286 is drum of SD of B1 process. D-286 is equipment that feeds and stores SD \"1.1ST,\" which was used for the heating of the HCL stripping tower reboiler. Since SD is highly-heated and may cause cavitation of P-2861A and B, PW is fed to cool down D-286. SD in D-286 shall be re-used as the heat source for STM BOILER and SRS. P-2861A and B is a pump to feeding TCS from STM BOILER and SRS to D-286, and then operate one among P-2861A and B while putting the remainder on standby. Because it is feeding to SRS and STM BOILER an SD, has managed the electrical conductivity of SD in the D-286. N2 is to seal in the gaseous layer of D-286, to prevent the dissolved oxygen to SD, and then to prevent that the electrical conductivity of the SD is increased contact with O2 and CO. P-2861A and B in the case of SD was increased electrical conductivity will stop at the interlock. D-286 is so fluid of SD, P-2861A and B is the reverse circulation piping and suction strainer is not available. P-2861A and B has a high capacity, because in the flow orifice of one plate cannot adjust the flow rate of the circulation piping, the flow orifice is attached 3 plate. LC28601 and LC28602 are adjusted to 80 % in the level control valve of D-286. This line is a pipe to supply the PW for cooling the SD to D-286, to prevent cavitation of the P-2861A and B due to evaporation of SD. TC2860 is adjusted to 90 °C in the temperature control valve of D-286.