CN105161143A - Effect-improved energy-efficient integrated method during physical starting of reactor - Google Patents

Abstract

The invention belongs to the technical field of a physical starting experiment of a reactor, and particularly relates to an effect-improved energy-efficient integrated method for improving operation economy of a power station during physical starting of the reactor. The method comprises the following steps: step 1, reducing the initial concentration of boric acid of a reactor core from 16 g/kg to 13g/kg; step 2, canceling injection of boric acid to the reactor core, when an experiment of emergency protection value measurement is performed, after all control rods fall into the reactor core, and lifting control rods of group 1-9 in sequence to the top of the reactor and lifting control rods of group 10 to a position, the height of which is 60% of the height of the reactor core, after the experiment is completed; step 3, under the hot operating condition, adjusting the eighth, ninth, and tenth rod groups, inserting the rod groups into the reactor core, and arranging the first to seventh shut-down rod groups to be outside the reactor; and step 4, modifying a calculation condition of the minimum shut-down concentration (CBmin) of boric acid to an inlet temperature, of a coolant, of 270 DEG C and keff of the reactor core of 0.99, adjusting all rod groups, inserting the rod groups into the bottom of the reactor, and taking all the rod groups out of the reactor core with the concentration of xenon being zero and considering the allowance of +1g/kg to reduce CBmin.

Description

The integrated approach of Synergistic and energy-saving between a kind of reactor physics starting period

Technical field

The invention belongs to reactor physics starting characteristics test technical field, be specifically related to the integrated approach of Synergistic and energy-saving between a kind of reactor physics starting period.

Background technology

VVER-1000/428 type reactor physics starts the process reaching most I monitoring power level, mainly comprises the following steps: promote control rod, large discharge dilution, stir and make muddy evenly, low discharge is diluted to most I monitoring power level.In this process, some method of operating occupies more overhaul critical path time, creates a large amount of radioactive liquid wastes, is mainly manifested in:

(1), under cold conditions operating mode, Technical specification requires that reactor core initial boron acid concentration is not less than 16g/kg, and all control rods insert reactor core.Initial boron acid concentration is too high, is diluted to critical boric acid concentration and can takies longer overhaul critical path time, produce a large amount of radioactive liquid wastes simultaneously, and the economy run external environment condition and power plant is unfavorable.

(2) under most I monitoring power level; when carrying out the measurement test of emergency protection value; after all control rods fall into reactor core; need to inject BAS to reactor core; boric acid concentration height about+1g/kg when making reactor core boric acid concentration more initial than test, then carries out liftings control rod, low discharge dilution, stirs evenly and reach most I and monitor power level condition.Injection BAS repeatedly and dilution operation, take longer overhaul critical path time, produce a large amount of radioactive liquid wastes simultaneously.

(3) under unit drops back hot operating mode, require to set up minimum shutdown boric acid concentration CB _min(CB _mindesign conditions are: coolant inlet temperature 270 DEG C, reactor core keff=0.99, and control rod all proposes, zero xenon, consider+1g/kg boric acid), all control rods insert reactor core simultaneously.Reactor core is inserted and CB at all control rods _minunder higher requirement, when reactor recovers critical again, control rod proposes reactor core and dilution will take longer critical path time, produces a large amount of radioactive liquid wastes simultaneously.

Summary of the invention

Technical matters to be solved by this invention is; not enough for prior art; thering is provided a kind of solves between the reactor physics starting period; reach for the first time and to reach critical and unit recession after critical, emergency protection is worth test again reach critical process after hot; take critical path time long; the problem that the Spent Radioactive liquid measure produced is large, with intensified response heap secondary shutdown ability, the integrated approach of Synergistic and energy-saving between economy a kind of reactor physics starting period of improving power station operation.

The technical solution adopted in the present invention is:

An integrated approach for Synergistic and energy-saving between the reactor physics starting period, comprises the following steps:

Step one, is reduced to 13g/kg by reactor core initial boron acid concentration by 16g/kg;

Step 2, during test that cancellation is carried out " emergency protection is worth and measures ", after all control rods fall into reactor core, the operation of boric acid is injected to reactor core, after test completes, in order 1-9 group control rod is promoted to heap top, the 10th group of control rod is promoted to 60% core height position;

Step 3, under thermal condition, regulate the 8th, 9,10 rod groups to insert reactor core, 1-7 shut-down rod group is in out-pile;

The design conditions of minimum shutdown boric acid concentration CBmin are revised as coolant inlet temperature 270 DEG C, reactor core keff=0.99 by step 4, and regulating rod group all inserts the heap end, and shut-down rod group all proposes reactor core, zero xenon, consider the allowance of+1g/kg, reduce Cbmin.

The invention has the beneficial effects as follows:

Reduce reactor and reach marginal time 12 hours, reduce radioactive wastewater and discharge about 120 tons, significantly improve power station economical operation benefit and environmental benefit, be specially:

(1) reactor core initial boron acid concentration is reduced to 13g/kg by 16g/kg, the radioactive liquid waste of generation more than 60 tons can be reduced, reduce by the reactor physics start-up time of more than 2 hours.

(2), when " emergency protection is worth and measures " test is carried out in cancellation, after all control rods fall into reactor core, inject the operation of boric acid to reactor core, can reduce generation radioactive liquid waste more than 30 tons, the reactor reducing more than 6 hours recovers the marginal time.

(3) by the optimization of reactor minimum shutdown boric acid concentration design conditions and control rod position, can reduce and produce radioactive liquid waste about 30 tons, reduce by the reactor physics start-up time of more than 4 hours, there is provided a large amount of standby negative reactivities to reactor core simultaneously, improve reactor secondary shutdown ability

Embodiment

Below in conjunction with embodiment, one provided by the invention is introduced:

An integrated approach for Synergistic and energy-saving between the reactor physics starting period, comprises the following steps:

(1) reactor core initial boron acid concentration is reduced to 13g/kg by 16g/kg, still meets Technical specification is not less than 0.02 requirement about subcriticality, and the criticality safety of reactor can be ensured.

(2), when " emergency protection is worth and measures " test is carried out in cancellation, after all control rods fall into reactor core, the operation of boric acid is injected to reactor core.After test completes, in order 1-9 group control rod is promoted to heap top, the 10th group of control rod is promoted to 60% core height position, like this, when the critical boric acid concentration of reactor core is known, before and after test, the change of the 10th group of control rod position can provide the reactive nargin of about 150pcm.Reactor safety recovery of critical state is made again by low discharge dilution mode.

(3) under hot operating mode, " all control rod insertion reactor cores " of former scheme is transform as " regulating rod group (the 8th, 9,10 rod group) inserts reactor core; shut-down rod group (1-7 rod group) is in out-pile ", a large amount of standby negative reactivities can be provided to reactor core, improve reactor secondary shutdown ability.The design conditions of minimum shutdown boric acid concentration CBmin are revised as coolant inlet temperature 270 DEG C, reactor core keff=0.99, and regulating rod group all inserts the heap end, and shut-down rod group all proposes reactor core, zero xenon, considers the allowance of+1g/kg, can reduce CBmin.

Before reactor start-up, reactor core boric acid concentration is diluted to 13g/kg by 16g/kg, and confirms that boric acid concentration meets the demands by sample analysis, to determine to meet Technical specification to be not less than 0.02 requirement about subcriticality.

During low-power physical test; all control rods when " emergency protection is worth and measures " test fall into reactor core; after completing guard signal reset; in order 1-9 group control rod is carried to heap top; 10th group of control rod is promoted to 60% core height position; the requirement of reactive speed should be met during promoting control rod, then make reactor safety recovery of critical state by low discharge dilution mode.

When unit arrives hot operating mode, carry to reactor core top by 1 ~ 7 group of control rod, 8 ~ 10 are positioned at reactor core bottom position, and reactor core boric acid concentration injects according in neutronics Feature Description, and meet Technical specification is not less than 0.01 requirement about subcriticality.

Result shows, this invention enhances the secondary shutdown ability of physical start-up process reaction heap, effectively shortens critical path time, decreases the discharge of radioactive liquid waste, improve economical operation benefit and the environmental benefit in power station.

Claims (1)

1. the integrated approach of Synergistic and energy-saving between the reactor physics starting period, is characterized in that: comprise the following steps:

Step one, is reduced to 13g/kg by reactor core initial boron acid concentration by 16g/kg;

Step 2, during test that cancellation is carried out " emergency protection is worth and measures ", after all control rods fall into reactor core, the operation of boric acid is injected to reactor core, after test completes, in order 1-9 group control rod is promoted to heap top, the 10th group of control rod is promoted to 60% core height position;

Step 3, under thermal condition, regulate the 8th, 9,10 rod groups to insert reactor core, 1-7 shut-down rod group is in out-pile;

The design conditions of minimum shutdown boric acid concentration CBmin are revised as coolant inlet temperature 270 DEG C, reactor core keff=0.99 by step 4, and regulating rod group all inserts the heap end, and shut-down rod group all proposes reactor core, zero xenon, consider the allowance of+1g/kg, reduce Cbmin.