Skip to main content

Seminar on the Advanced Boiling Water Reactor (ABWR) by Hitachi [vendor of reactor]

Seminar on the Advanced Boiling Water Reactor (ABWR) by Hitachi [vendor of reactor]
University of Birmingham, 21st-22nd April 2015
Notes by William Gaskell MSc PTNR Birmingham

Introduction to ABWR

By Mr K. Moriya of Hitachi-GE
[Information in this seminar is based on the Japanese safety licence for ABWR which will vary from ABWR UK design after GDA process with ONR]
Hitachi aim to establish an ABWR chair in academia at undergraduate level. [–perhaps at Bangor University in Wales]
Interesting specifications of reactor:
·         Thermal power is 3975MW
·         Temperature of steam from core is 287˚C
·         10 pumps (RIPs) in the pressure vessel of reactor
   Safety work using STAR-CD code to model pump trip in reactor so that we know how to control core in such situations
·         60 Hz 52” blade turbines used in ABWR to generate electricity from steam produced in core
·         Each emergency backup diesel generator has 4000kW capacity [I would think 50MW would be needed to keep reactor running normally as coolant pumps require large amount of energy to operate]
Inherently Safe:
·         Negative void feedback meaning no risk of Chernobyl style accident
·         Atmosphere Control (AC) system injects Nitrogen gas to prevent hydrogen gas burning (Fukushima-style)
·         Flammability Control System (FCS) recombines Hydrogen gas + Oxygen created by radiolysis (of water) in the reactor [radiation catalysing the disintegration of water at high temperature into oxygen and hydrogen gaseous molecules]
·         It would take at least 2 days to create explosive 5% concentration of Oxygen (+ Hydrogen)

Horizon Nuclear Power

Power company building and operating ABWR in UK at Wylfa in Anglesey, Wales  and Oldbury, in Gloucestershire in England
·         Next supply chain event in North Wales details are on Horizon’s website

Robot and Remote-Controlled Technology

Prof Hijime Asama, University of Tokyo

Fukushima 2011 Accident (Level 7 on International Nuclear Events Scale)

Situation:
·         There was explosion of Hydrogen in units 1, 3 & 4 and leakage of cooling water in all units 1-4.
·         Spent fuel pool was heating up and water evaporating.
Plan for recovery:
Phase 1: COMPLETED
Fuel removal from spent fuel ponds
Phase 2: Current phase
Removing fuel debris (to take 60 years)
Phase 3: Complete decommissioning of site

·         Need robots to achieve this!
·         ROBOTAD (Robotics Task Force for Anti-Disaster)
One of the problems faced by robots on site was stairs in Fukushima reactor being a different width in the reactor (70cm) to the specifications in the plans (90cm).
Robotics industry needs to set up long term
·         Projects
·         Facilities
·         Long-lived robots with A.I.
Lesson Learned from Fukushima:
Units 2 RCIC (emergency cooling system) managed to operate for 3 days after tsunami before melt-down – design expectancy was only 8 hours.

Construction of ABWR

ABWR reactor building dimensions: 60x60x60m – high power density!
Improving construction efficiency by visualising the final result

Control of ABWR

Mr Y. Koda, Hitachi-GE
Reactor is controlled using following techniques in order of preference:
1.       Using RIPs and controlling flow rate of coolant in core
2.       Control Rods – very fine reactivity control can be achieved with very small notches for each step of insertion [he seems to indicate on startup/low power regimes the other way around]
3.       Turbine control valve + dome pressure (has less effect in ABWR than in BWR)
Control systems:
1.       RFC (Recirculation Flow Control) + RC&IS (Rod Control and Insertion System)
   Reactivity control (how much fission rate increases/decreases per generation of fissions – rate of propagation of chain reaction)
2.       EHC (Electric Hydraulic Control System)
   Turbine speed
   Pressure of coolant in core
3.       FDWC (Feedwater Control)
   Core water level
Increasing the pump speed would increase the power of the reactor. Decreasing would reduce power as would inserting control rods.
No void positive reactivity coefficient (bubbles in coolant water in core causing the rate of fission to increase uncontrollably in core and create Chernobyl-style disaster) as Doppler effect of temperature on material coefficient lowers reactivity with increased temperature in fuel.
Shut down signal acronym SCRM
Suppression pool cools down steam when reactor depressurized in trip (accident like Fukushima Tsunami)
Next ABWR seminar at Imperial College, London, September 2015 location to be arranged.


Comments

Popular posts from this blog

Effective Altruism

It’s not quite Aldous Huxley or George Orwell. I think altruism is what the Dalai Lama perhaps aspires to; kindness, clarity and compassion. This is about humanity rather than about more abstract terms such as the value of money as a metric for happiness or altruism. When dealing with diagnostic labels in mental health, you have to decide whether money is in fact a factor is such a diagnosis or not, given your politics on what money is. Therefore, mental health should be more of a framework that enables those who chose to give up their freedom to live a healthy life, in safety and security within the system. People seek opportunity, therefore by providing such a framework and a decent introduction to a healthy life free of unhappiness is essential to providing a service that is altruistic. We can see this from the British government’s model of social care and welfare programmes, which have proven resilient to mass immigration, a changing demographic, leading to the disruption in

Brexit debate, should Britain leave the EU for the sake of ECHR?

I think the problem with this type of communication is that it relies on the out crowd being popular when in fact I felt convinced to vote to leave to EU because "they don't get it" and that is called abuse in Bristol and could get you arrested. Most Europeans have a poor education compared to the leading British schools as a result of their limited capacity to live well meaning that it is a technical form of slavery if they succeed in any way when someone from a more privileged backgrounds competes with them if the competition is not fair and equal. For example when it comes to sexual relations with their women. In sports referees have to enforce the rules of the game as well as the relative standing of the different teams in order for there to be a fair competition. Unfortunately, in Europe this does not happen so we should leave, but in the interests of world peace and investing in the future we should stay in the EU as it will get better for

Notes from Energy & Utility Forum 2017

1. Robert Symons, CEO of Western Power Distribution said: “Energy demand could rise by 100% by 2030. Smart grids will be needed to manage electric vehicle charging so that the usage does not exceed the supply capacity at any time during the day.” 2. Spoke to Harry Vickers, Business Development Manager of Camborne Energy Storage, Camborne Capital at the Energy and Utility Forum in London on October 23rd 2017. He told me his company is working with Elon Musk to bring Tesla battery grid storage solutions to the UK. 3. Spoke to Sally Barrett-Williams, Chairman of Energy and Utility Forum on October 23rd, who said subsidies for solar projects had ended and her company’s focus has shifted to energy storage schemes. 4. Spoke to Simon Dowland, PhD, at 13:00 on Sunday 29th October, Simon is now working up in Cambridge at the Cavendish Physics Laboratory at the University of Cambridge, he is working in industry for the company Eight19 Ltd a spin off from a research project to bring ne