SlideShare uma empresa Scribd logo
1 de 2
Baixar para ler offline
•• 
Millennium Seed Bank Project, Wakehurst Place, Ardingly, 
West Sussex RH17 6TN, UK 
© Copyright 2009, Board of Trustees of the Royal Botanic Gardens, Kew 
www.kew.org/msbp 
Seed bank design: seed 
drying rooms 
Simon Linington and Keith Manger, Seed C Technical Information Sheet_11 onservation Department 
The effective drying of orthodox 
seeds prior to cold storage is the key 
to successful seed banking. Drying 
prolongs storage life, allows seeds 
to tolerate extreme temperatures, 
prevents germination, and reduces 
attack by predators and pathogens. 
For long-term conservation, the aim 
is to reduce seed moisture status to 
15% equilibrium relative humidity 
(eRH) at 15ºC. This is about 3-7% 
moisture content (on a fresh weight 
basis), depending on the oil content 
of the seeds. 
Technical Information Sheet_11 
Equipment specifications 
Further reading 
Linington, S.H. (2003). The design 
of seed banks, pp. 591-636. In: R.D. 
Smith, J.B. Dickie, S.H. Linington, 
H.W. Pritchard and R.J. Probert 
(eds), Seed Conservation: turning 
science into practice. Royal Botanic 
Gardens, Kew. 
A dry room is the most appropriate 
drying method when you need to 
dry large quantities of seed at the 
same time (see table below). Dry 
rooms also provide safe storage 
prior to seed cleaning and a suitable 
location to package samples for 
storage or to warm up frozen 
samples that have been removed 
from the cold room. 
This information sheet explains how 
to set up a dry room. Refer to Low-cost 
Drying (Technical Information 
Sheet_08) and Linington (2003) for 
other drying methods. 
Description Model/Product Supplier 
Insulation Panellised Styrofoam, 100mm thick Local refrigeration company 
Sorption dryer Dehumidifying systems Munters 
www.munters.co.uk 
Chilling facilities Refrigeration unit Local refrigeration company 
Stacking crates Plastic trays (ventilated) 
600L x 400W x 193H, ref:21035 
600L x 400W x 120H, ref:20016 
Dollies, ref:91005 
Allibert Handling 
www.allibert.com 
Hygrometer to measure seed moisture status AW-DIO sensor with HygroPalm 3 display 
unit or HygroClip SC04 sensor with 
HygroLog-D unit. 
Rotronic Instruments (UK) Ltd. 
www.rotronic.com 
Data loggers for measuring relative humidity Tiny Tag and Tiny View data loggers Gemini Data Loggers (UK) Ltd. 
www.geminidataloggers.com 
Please note that the above equipment is used by the Millennium Seed Bank Project and has been chosen carefully using our many years’ experience. The list of 
suppliers is for guidance only and does not represent an endorsement by the Royal Botanic Gardens, Kew. The manufacturer’s instructions must be followed 
when using any of the equipment referred to in this Information Sheet. 
Designing a dry room 
It is important to obtain specialist 
advice when creating a dry room. 
However, seed curators and 
conservation practitioners should 
understand the basic principles 
in order to guide the design. The 
fundamental principle is to create 
a sealed room with low relative 
humidity and a cool temperature 
(the MSB recommends 15% RH 
at 15ºC). Good insulation is also 
important to reduce energy usage 
in cooling and drying. 
The key questions when designing a 
dry room are: 
What size and shape should the 
room be? 
The maximum volume of material 
that will need to be dried at any 
one time will determine the size of 
room required. A small seed bank 
might require a volume of around 
25m³, whereas an international seed 
bank is more likely to require a dry 
room in the region of 125m³. 
What is the likely moisture load? 
Apart from the seeds themselves, 
other sources of moisture need to be 
taken into account when calculating 
dry room size. Together, these make 
up the moisture load, expressed 
as kilograms per hour. Working 
to a slight positive pressure, the 
dryer should be able to maintain 
the required conditions under the 
potential moisture load from: 
• Wet seeds 
The moisture status and amount of 
seeds in the room at any one time 
will vary, so it is difficult to estimate 
the exact moisture load. 
Unless batches of very wet seeds 
will be placed in the room at 
frequent intervals, there is no 
benefit in designing for a ‘worst 
case scenario’. The system may fall 
outside the optimum conditions 
for a short amount of time, but the 
dehumidifier will then start to work 
more efficiently and will rapidly 
return the room to the desired 
moisture status. 
• People in the room 
A person carrying out non-strenuous 
work in a dry room will release 
approximately 60g water vapour per 
hour. 
• Moist air entering the room 
Depends on the frequency of door-opening, 
the size of the air-lock, and 
the external air conditions. 
• Fresh air make-up 
Depends on the number of people 
using the room. 
• Permeation through the structure 
This should be negligible. 
• Leakage into the dehumidifier 
Moisture leaking into the 
dehumidifier is likely to be zero for a 
well-sealed machine. 
What about working conditions 
for staff in the room? 
A fresh intake of oxygen into the 
room is required, to maintain safe 
working conditions for staff. With 
the exception of very small dry 
rooms, air entering via the door will 
not supply sufficient oxygen to the 
room. Allow for a steady 10% fresh 
air make-up via the dry-air duct 
work, into the process air flow. 
The supply of fresh air can be shut 
off when there is sufficient oxygen 
in the room. This is controlled via a 
carbon dioxide monitoring device, 
linked to an automated fresh air 
intake valve in the process air duct. 
Seek further technical advice if this 
option is used. 
Below: Tasmanian Seed Conservation Centre, 
Australia - dry room with sorption dryer unit 
and -20°C chiller cabinets for seed storage 
Below: Dry room at The Lombardy Seed Bank, 
University of Pavia, Italy, with collections in 
stacked crates 
Comparing seed drying facilities 
Drying capacity Cost (UK prices) 
Purpose-built dry 
room 
in excess of 500L of 
seed material 
£30,000 (converting 
an existing cold room 
into a dry room will 
be cheaper) 
Bespoke drying 
cabinet with desiccant 
dehumidifier unit 
500L of seed material £15,000 
Incubator-dryer about 100L of seed 
material 
£2,500-4,000 
(incubator purchase 
price) 
Silica gel in a 60 litre 
drum 
up to 25L of seed 
materal 
£200 
In order to avoid dehydration, staff 
should only work in the dry room 
for a maximum of 2 hours and 
should then drink plenty of water 
when leaving the dry room. 
Another problem associated with 
operating a dry room is a build-up 
of electrostatic charge due to 
the dry conditions. Use anti-static 
footwear and/or an anti-static gun, 
especially when dealing with tiny 
seeds. All room fixtures should be 
well-earthed
If the total uncleaned peak seed 
volume is sufficiently small, (less 
than 25m³) one or two incubator-dryers 
might be a more appropriate 
option for drying. 
It is helpful to mark out the 
dimensions of the proposed dry 
room on the ground. Ideally, locate 
the dry room close to, or attached 
to, the seed cleaning area and 
adjacent to the cold room(s). An 
oblong-shaped room is better 
than a square one. Supplying dry 
air on one of the short walls and 
extracting it from the opposite wall 
will give a good air flow to most 
parts of the room (though ‘dead 
spots’ will exist). 
Depending on the frequency of 
access to the room and the humidity 
of the external conditions, an air 
lock (small lobby) may be required 
to minimise the entry of humid air 
into the room when the door is 
opened. A 2m² air lock will be large 
enough for at least one person 
holding a crate to enter easily. 
Include a secondary (emergency) 
exit door from the dry room. 
What materials should be used? 
Ideally, install a new prefabricated 
structure, either as a stand-alone 
room or within a larger existing 
room. Construct walls and ceiling 
with Styrofoam panels (100mm 
thick). For the floor, cover a 
moisture-proof membrane with 
Styrofoam insulation, and top with 
marine plywood and epoxy-resin 
screed. Doors must be well insulated 
and windows (including those in the 
doors) should be double-glazed. 
If an existing brick- or wood-built 
room is to be used, install a 
moisture barrier (perhaps glazed 
tiles or plastic sheeting) on all 
internal surfaces. Install thermal 
insulation on the outside of the 
walls (and ceiling). Both will reduce 
energy usage in maintaining the dry 
room conditions and the external 
insulation should help minimise 
condensation in the walls. 
How is the air dried and cooled? 
The drier must have enough 
capacity to deliver about six air 
changes per hour to the drying 
room. This is often the limiting 
factor. To estimate the likely 
suitability of a dryer, compare its 
airflow capability with six times the 
volume of the dry room. Confirm 
this with the supplier/installer. Note 
that refrigeration dryers are not 
designed to deliver this condition. 
The MSB recommends a rotary 
sorption dryer containing a silica gel 
or lithium chloride drying agent. 
If possible, install two dryers, each 
capable of coping with 66% of the 
moisture load. 
The dryer creates heat during the 
drying process and should ideally 
be placed outside the room (in a 
ventilated area). Connect the drier 
to the room via insulated supply and 
extract ducts, of sufficient diameter 
not to impede air flow. 
Possible layout of dry room facilities 
The direction of the air flow is indicated by the arrows. 
This ‘process air’ dries the room and 
should be supplied, via a chiller, 
high up at one end of the room and 
extracted low down at the other 
end of the room. The drying agent 
picks up moisture from the process 
air and is then re-dried by the 
second (‘reactivation’) air flow. Air 
is drawn into the dryer, heated, and 
passed over the drying agent. The 
wet air produced by this process 
needs to be ducted to the outside 
of the building. 
The location of the controlling 
humidistat is important. Place the 
humidistat halfway along one 
of the longer walls of the room. 
Construct a map of humidity in 
the working dry room, using an RH 
meter to guide where to best locate 
the stacks of crates for drying. 
If the dryer is located within the 
dry room, ensure that the process 
air mixes rapidly with the cooling 
system air. Duct the wet reactivation 
air out of the room. The chiller will 
need to be located in the room and 
be capable of cooling the heat load 
from the dryer, achieving a room 
temperature of 15ºC. 
Reactivation air 
flow 
Process air flow 
Prefabricated dry 
room constructed 
with 100mm 
Styrofoam panels 
Humidistat 
Dryer 
Chiller 
Flourescent lights 
Stack 
Air extract 
(low) 
Process air 
supply (high) 
Duct either 
over or 
alongside 
room 
Air lock 
with 2 
doors + 
windows 
Bench with electrical sockets 
Double glazed window 
Fresh 
air 
intake 
Stack 
Secondary 
exit 
Below: Crates stacked on moveable trolleys in the MSB dry room, with seed collections 
contained in porous bags 
Assess the likely collection intake 
per month during a typical year 
and identify the peak volume of 
material (for some seed banks, the 
dry room may need to hold a whole 
year’s collections). The number of 
seeds per collection, and the size of 
these seeds will greatly affect the 
volume estimations. 
Make these estimations on the basis 
of uncleaned collections, unless 
the seeds will definitely be cleaned 
beforehand. Assume that drying 
will take at least one month. 
Seed drying room: worked 
example 
If the volume of an ‘average’ un-cleaned 
seed collection (V) = 0.002m³ 
Number of collections in dry room 
during peak period (N) = 500 
Assume that collections are spread in 
thin layers on paper inserts, within 
self-stacking crates on trolleys. If 
collections are to be held in bags, 
less space is required but drying time 
will increase. 
Height of crate (H) = 0.12m 
Width of crate (W) = 0.4m 
Length of crate (L) = 0.6m 
Proportion of crate filled (P) = 0.25 
(especially if thin-layer drying) 
Trolley Height (Z) = 0.3m 
Number of collections per crate (A) 
= (H * W * L * P) / V = 3 
(round down to avoid part collections 
in a crate) 
Number of crates (B) 
= N / A = 167 (round up) 
A stack of self-stacking crates on a 
trolley should not exceed a height of 
2m. 
Number of crates in stack (C) 
= (2 - Z) / H = 14 (round down) 
Number of stacks (D) 
= B / C = 12 (round up) 
Floor area of stacks (E) 
= D * W * L = 2.88m² 
In order to allow sufficient working 
space (including a table) and good 
air circulation, crates should only 
occupy about 25% of the floor area. 
Therefore, the total floor area will 
need to be 4 times the area occupied 
by the crates. 
Required dry room floor area (F) 
= E * 4 = 11.52m² 
The height of the room is likely to be 
around 2.5m. 
Dry room volume (G) 
= F * 2.5 = 28.8m³

Mais conteúdo relacionado

Mais procurados

vertical gardening system
vertical gardening systemvertical gardening system
vertical gardening systemNaveen C
 
Indoor Plants
Indoor PlantsIndoor Plants
Indoor Plantsjnursery
 
Green house ppt
Green house pptGreen house ppt
Green house pptTaherbond
 
Terrace Garden / Green Roof
Terrace Garden / Green RoofTerrace Garden / Green Roof
Terrace Garden / Green RoofAnupama Krishnan
 
Planting design
Planting designPlanting design
Planting designanjana5na
 
Assignment on landscape designing
Assignment on   landscape designingAssignment on   landscape designing
Assignment on landscape designingtivar rose
 
Indoor and rooftop Landscape.
Indoor and rooftop Landscape.Indoor and rooftop Landscape.
Indoor and rooftop Landscape.Neha Khare
 
Elements of landscape design
Elements of landscape designElements of landscape design
Elements of landscape designDiksha Sharma
 
Elements of landscape
Elements of landscape Elements of landscape
Elements of landscape Diksha Sharma
 
Parking regulations KMBR
Parking regulations KMBRParking regulations KMBR
Parking regulations KMBRAjay Dev
 
English landscape gardens by ABHISHEK CHHONKAR
English landscape gardens by ABHISHEK CHHONKAREnglish landscape gardens by ABHISHEK CHHONKAR
English landscape gardens by ABHISHEK CHHONKARAbhishek Singh
 

Mais procurados (20)

Interior plants
Interior plantsInterior plants
Interior plants
 
Innovative roof top gardening
Innovative roof top gardeningInnovative roof top gardening
Innovative roof top gardening
 
vertical gardening system
vertical gardening systemvertical gardening system
vertical gardening system
 
Types of gardens
Types of gardensTypes of gardens
Types of gardens
 
Indoor Plants
Indoor PlantsIndoor Plants
Indoor Plants
 
Roof Garden
Roof GardenRoof Garden
Roof Garden
 
Green house ppt
Green house pptGreen house ppt
Green house ppt
 
Terrace Garden / Green Roof
Terrace Garden / Green RoofTerrace Garden / Green Roof
Terrace Garden / Green Roof
 
Planting design
Planting designPlanting design
Planting design
 
Assignment on landscape designing
Assignment on   landscape designingAssignment on   landscape designing
Assignment on landscape designing
 
Hardscaping
HardscapingHardscaping
Hardscaping
 
LANDSCAPE CASE STUDY
LANDSCAPE CASE STUDYLANDSCAPE CASE STUDY
LANDSCAPE CASE STUDY
 
Indoor and rooftop Landscape.
Indoor and rooftop Landscape.Indoor and rooftop Landscape.
Indoor and rooftop Landscape.
 
Elements of landscape design
Elements of landscape designElements of landscape design
Elements of landscape design
 
Elements of landscape
Elements of landscape Elements of landscape
Elements of landscape
 
Healing Gardens: Creating Places for Restoration, Meditation, and Sanctuary
Healing Gardens: Creating Places for Restoration, Meditation, and SanctuaryHealing Gardens: Creating Places for Restoration, Meditation, and Sanctuary
Healing Gardens: Creating Places for Restoration, Meditation, and Sanctuary
 
Parking regulations KMBR
Parking regulations KMBRParking regulations KMBR
Parking regulations KMBR
 
Principles and elements of landscape design
Principles and elements of landscape designPrinciples and elements of landscape design
Principles and elements of landscape design
 
Landscaping
LandscapingLandscaping
Landscaping
 
English landscape gardens by ABHISHEK CHHONKAR
English landscape gardens by ABHISHEK CHHONKAREnglish landscape gardens by ABHISHEK CHHONKAR
English landscape gardens by ABHISHEK CHHONKAR
 

Destaque (15)

BANK ON DESIGN (BOND)
BANK ON DESIGN (BOND)BANK ON DESIGN (BOND)
BANK ON DESIGN (BOND)
 
Bank design
Bank designBank design
Bank design
 
World bank project a case study of africa region
World bank project a case study of africa region World bank project a case study of africa region
World bank project a case study of africa region
 
Alex Haw Lecture 130803 - South Bank Centre - Active Architecture -196
Alex Haw Lecture 130803 - South Bank Centre - Active Architecture -196Alex Haw Lecture 130803 - South Bank Centre - Active Architecture -196
Alex Haw Lecture 130803 - South Bank Centre - Active Architecture -196
 
Reactive Design Patterns
Reactive Design PatternsReactive Design Patterns
Reactive Design Patterns
 
One Bank, One Architecture
One Bank, One ArchitectureOne Bank, One Architecture
One Bank, One Architecture
 
Building a Bank out of Microservices (NDC Sydney, August 2016)
Building a Bank out of Microservices (NDC Sydney, August 2016)Building a Bank out of Microservices (NDC Sydney, August 2016)
Building a Bank out of Microservices (NDC Sydney, August 2016)
 
History of Banking
History of BankingHistory of Banking
History of Banking
 
Origin of banking
Origin of bankingOrigin of banking
Origin of banking
 
Bank of America Case Study - Enterprise Architecture in Mobile Banking
Bank of America Case Study - Enterprise Architecture in Mobile BankingBank of America Case Study - Enterprise Architecture in Mobile Banking
Bank of America Case Study - Enterprise Architecture in Mobile Banking
 
The History of Banking
The History of Banking The History of Banking
The History of Banking
 
Literature review and case study of corporate architecture
Literature review and case study of corporate architectureLiterature review and case study of corporate architecture
Literature review and case study of corporate architecture
 
History of banking
History of bankingHistory of banking
History of banking
 
Office Layout
Office LayoutOffice Layout
Office Layout
 
Hospital design
Hospital designHospital design
Hospital design
 

Semelhante a Seed Bank Design: Seed Drying Rooms

Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...
Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...
Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...yogeshysumthane
 
4068 plant tissue culture lab design
4068 plant tissue culture lab design4068 plant tissue culture lab design
4068 plant tissue culture lab designSheena Prem
 
Small-Scale Seed Drying Methods
Small-Scale Seed Drying MethodsSmall-Scale Seed Drying Methods
Small-Scale Seed Drying MethodsSeeds
 
Rotary dryer catalogue
Rotary dryer catalogueRotary dryer catalogue
Rotary dryer cataloguechinadjks
 
M mold prevention it's in the water 3 hr sa9506
M mold prevention it's in the water 3 hr  sa9506M mold prevention it's in the water 3 hr  sa9506
M mold prevention it's in the water 3 hr sa9506aeuse
 
Performance Evaluation of a Developed Multipurpose Solar Dryer
Performance Evaluation of a Developed Multipurpose Solar DryerPerformance Evaluation of a Developed Multipurpose Solar Dryer
Performance Evaluation of a Developed Multipurpose Solar Dryerijtsrd
 
The International Journal of Engineering and Science (The IJES)
The International Journal of Engineering and Science (The IJES)The International Journal of Engineering and Science (The IJES)
The International Journal of Engineering and Science (The IJES)theijes
 
design and development of portable ripening chamber
design and development of portable ripening chamberdesign and development of portable ripening chamber
design and development of portable ripening chamberAjit Saruk
 
Temperature and shade regulation in green house
Temperature and shade regulation in green houseTemperature and shade regulation in green house
Temperature and shade regulation in green houseiari
 

Semelhante a Seed Bank Design: Seed Drying Rooms (20)

Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...
Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...
Dr. Yogesh Sumthane Assistant Professor College of Forestry Banda University ...
 
4068 plant tissue culture lab design
4068 plant tissue culture lab design4068 plant tissue culture lab design
4068 plant tissue culture lab design
 
Small-Scale Seed Drying Methods
Small-Scale Seed Drying MethodsSmall-Scale Seed Drying Methods
Small-Scale Seed Drying Methods
 
Moisture control in storage
Moisture control in storageMoisture control in storage
Moisture control in storage
 
Rotary dryer catalogue
Rotary dryer catalogueRotary dryer catalogue
Rotary dryer catalogue
 
Greenhouse technology
Greenhouse technologyGreenhouse technology
Greenhouse technology
 
CA in silo bin
CA in silo binCA in silo bin
CA in silo bin
 
Economics of drying aquafeed
Economics of drying aquafeedEconomics of drying aquafeed
Economics of drying aquafeed
 
STORAGE: Aerating stored grain
STORAGE: Aerating stored grainSTORAGE: Aerating stored grain
STORAGE: Aerating stored grain
 
M mold prevention it's in the water 3 hr sa9506
M mold prevention it's in the water 3 hr  sa9506M mold prevention it's in the water 3 hr  sa9506
M mold prevention it's in the water 3 hr sa9506
 
Performance Evaluation of a Developed Multipurpose Solar Dryer
Performance Evaluation of a Developed Multipurpose Solar DryerPerformance Evaluation of a Developed Multipurpose Solar Dryer
Performance Evaluation of a Developed Multipurpose Solar Dryer
 
12 drying
12 drying12 drying
12 drying
 
The International Journal of Engineering and Science (The IJES)
The International Journal of Engineering and Science (The IJES)The International Journal of Engineering and Science (The IJES)
The International Journal of Engineering and Science (The IJES)
 
design and development of portable ripening chamber
design and development of portable ripening chamberdesign and development of portable ripening chamber
design and development of portable ripening chamber
 
Temperature and shade regulation in green house
Temperature and shade regulation in green houseTemperature and shade regulation in green house
Temperature and shade regulation in green house
 
Solar food drying
Solar food drying Solar food drying
Solar food drying
 
W2 lab design_new2
W2 lab design_new2W2 lab design_new2
W2 lab design_new2
 
Cell culture
Cell cultureCell culture
Cell culture
 
Vacuum drying.pptx
Vacuum drying.pptxVacuum drying.pptx
Vacuum drying.pptx
 
Fluid beds
Fluid bedsFluid beds
Fluid beds
 

Mais de Seeds

Free Gardening Art Posters
Free Gardening Art PostersFree Gardening Art Posters
Free Gardening Art PostersSeeds
 
Seeds of Justice, Seeds of Hope
Seeds of Justice, Seeds of HopeSeeds of Justice, Seeds of Hope
Seeds of Justice, Seeds of HopeSeeds
 
Mahatma K. Gandhi Quotes
Mahatma K. Gandhi QuotesMahatma K. Gandhi Quotes
Mahatma K. Gandhi QuotesSeeds
 
Good Food Helps your Children Excel in School
Good Food Helps your Children Excel in SchoolGood Food Helps your Children Excel in School
Good Food Helps your Children Excel in SchoolSeeds
 
Companion Planting Chart increases Vegetable Production
Companion Planting Chart increases Vegetable ProductionCompanion Planting Chart increases Vegetable Production
Companion Planting Chart increases Vegetable ProductionSeeds
 
Edible Schoolyards = Academic Success & Gardening with Children
Edible Schoolyards = Academic Success & Gardening with ChildrenEdible Schoolyards = Academic Success & Gardening with Children
Edible Schoolyards = Academic Success & Gardening with ChildrenSeeds
 
Simple Square Foot Gardening for Schools - Teacher Guide
Simple Square Foot Gardening for Schools - Teacher GuideSimple Square Foot Gardening for Schools - Teacher Guide
Simple Square Foot Gardening for Schools - Teacher GuideSeeds
 
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much More
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much MoreCity Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much More
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much MoreSeeds
 
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet Care
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet CareHorseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet Care
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet CareSeeds
 
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much More
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much MoreCity Beekeeping ~ Honey for Health ~ Resouces, Books & Much More
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much MoreSeeds
 
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...Seeds
 
Free Xeriscape Gardening Manuals, Books, Resources & Much More
Free Xeriscape Gardening Manuals, Books, Resources &  Much MoreFree Xeriscape Gardening Manuals, Books, Resources &  Much More
Free Xeriscape Gardening Manuals, Books, Resources & Much MoreSeeds
 
City Chickens for your Organic Garden
City Chickens for your Organic GardenCity Chickens for your Organic Garden
City Chickens for your Organic GardenSeeds
 
Ram Water Pumps - Using No Fuel and No Electricity
Ram Water Pumps - Using No Fuel and No ElectricityRam Water Pumps - Using No Fuel and No Electricity
Ram Water Pumps - Using No Fuel and No ElectricitySeeds
 
Huerto Ecológico, Tecnologías Sostenibles, Agricultura Organica
Huerto Ecológico, Tecnologías Sostenibles, Agricultura OrganicaHuerto Ecológico, Tecnologías Sostenibles, Agricultura Organica
Huerto Ecológico, Tecnologías Sostenibles, Agricultura OrganicaSeeds
 
City Farming - Backyard Farming - Urban Farming Books, Resources & Links
City Farming - Backyard Farming - Urban Farming Books, Resources & LinksCity Farming - Backyard Farming - Urban Farming Books, Resources & Links
City Farming - Backyard Farming - Urban Farming Books, Resources & LinksSeeds
 
The Wicking Worm Bed Revolution for Drought Gardening
The Wicking Worm Bed Revolution for Drought GardeningThe Wicking Worm Bed Revolution for Drought Gardening
The Wicking Worm Bed Revolution for Drought GardeningSeeds
 
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer Droughts
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer DroughtsGarden Wicking Beds = Water Wise Gardening for Dry Lands & Summer Droughts
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer DroughtsSeeds
 
Self Watering Container Gardens for Summer Drought Gardening & Arid Lands
Self Watering Container Gardens for Summer Drought Gardening & Arid LandsSelf Watering Container Gardens for Summer Drought Gardening & Arid Lands
Self Watering Container Gardens for Summer Drought Gardening & Arid LandsSeeds
 
A Manual for Growing Food in Arid Lands & Summer Droughts
A Manual for Growing Food in Arid Lands & Summer DroughtsA Manual for Growing Food in Arid Lands & Summer Droughts
A Manual for Growing Food in Arid Lands & Summer DroughtsSeeds
 

Mais de Seeds (20)

Free Gardening Art Posters
Free Gardening Art PostersFree Gardening Art Posters
Free Gardening Art Posters
 
Seeds of Justice, Seeds of Hope
Seeds of Justice, Seeds of HopeSeeds of Justice, Seeds of Hope
Seeds of Justice, Seeds of Hope
 
Mahatma K. Gandhi Quotes
Mahatma K. Gandhi QuotesMahatma K. Gandhi Quotes
Mahatma K. Gandhi Quotes
 
Good Food Helps your Children Excel in School
Good Food Helps your Children Excel in SchoolGood Food Helps your Children Excel in School
Good Food Helps your Children Excel in School
 
Companion Planting Chart increases Vegetable Production
Companion Planting Chart increases Vegetable ProductionCompanion Planting Chart increases Vegetable Production
Companion Planting Chart increases Vegetable Production
 
Edible Schoolyards = Academic Success & Gardening with Children
Edible Schoolyards = Academic Success & Gardening with ChildrenEdible Schoolyards = Academic Success & Gardening with Children
Edible Schoolyards = Academic Success & Gardening with Children
 
Simple Square Foot Gardening for Schools - Teacher Guide
Simple Square Foot Gardening for Schools - Teacher GuideSimple Square Foot Gardening for Schools - Teacher Guide
Simple Square Foot Gardening for Schools - Teacher Guide
 
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much More
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much MoreCity Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much More
City Farming, Backyard Farming, & Urban Farming - , Resources, Links & Much More
 
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet Care
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet CareHorseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet Care
Horseback Riding Therapy, Natural Horse Care, Natural Pet Food, Natural Pet Care
 
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much More
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much MoreCity Beekeeping ~ Honey for Health ~ Resouces, Books & Much More
City Beekeeping ~ Honey for Health ~ Resouces, Books & Much More
 
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...
Free Water Wise Gardening Handbooks & Drought Gardening, Manuals, Books & Muc...
 
Free Xeriscape Gardening Manuals, Books, Resources & Much More
Free Xeriscape Gardening Manuals, Books, Resources &  Much MoreFree Xeriscape Gardening Manuals, Books, Resources &  Much More
Free Xeriscape Gardening Manuals, Books, Resources & Much More
 
City Chickens for your Organic Garden
City Chickens for your Organic GardenCity Chickens for your Organic Garden
City Chickens for your Organic Garden
 
Ram Water Pumps - Using No Fuel and No Electricity
Ram Water Pumps - Using No Fuel and No ElectricityRam Water Pumps - Using No Fuel and No Electricity
Ram Water Pumps - Using No Fuel and No Electricity
 
Huerto Ecológico, Tecnologías Sostenibles, Agricultura Organica
Huerto Ecológico, Tecnologías Sostenibles, Agricultura OrganicaHuerto Ecológico, Tecnologías Sostenibles, Agricultura Organica
Huerto Ecológico, Tecnologías Sostenibles, Agricultura Organica
 
City Farming - Backyard Farming - Urban Farming Books, Resources & Links
City Farming - Backyard Farming - Urban Farming Books, Resources & LinksCity Farming - Backyard Farming - Urban Farming Books, Resources & Links
City Farming - Backyard Farming - Urban Farming Books, Resources & Links
 
The Wicking Worm Bed Revolution for Drought Gardening
The Wicking Worm Bed Revolution for Drought GardeningThe Wicking Worm Bed Revolution for Drought Gardening
The Wicking Worm Bed Revolution for Drought Gardening
 
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer Droughts
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer DroughtsGarden Wicking Beds = Water Wise Gardening for Dry Lands & Summer Droughts
Garden Wicking Beds = Water Wise Gardening for Dry Lands & Summer Droughts
 
Self Watering Container Gardens for Summer Drought Gardening & Arid Lands
Self Watering Container Gardens for Summer Drought Gardening & Arid LandsSelf Watering Container Gardens for Summer Drought Gardening & Arid Lands
Self Watering Container Gardens for Summer Drought Gardening & Arid Lands
 
A Manual for Growing Food in Arid Lands & Summer Droughts
A Manual for Growing Food in Arid Lands & Summer DroughtsA Manual for Growing Food in Arid Lands & Summer Droughts
A Manual for Growing Food in Arid Lands & Summer Droughts
 

Último

Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxraviapr7
 
How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17Celine George
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationMJDuyan
 
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...Nguyen Thanh Tu Collection
 
CAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxCAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxSaurabhParmar42
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...raviapr7
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesCeline George
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptxmary850239
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17Celine George
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.raviapr7
 
General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and stepobaje godwin sunday
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17Celine George
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxiammrhaywood
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...CaraSkikne1
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfMohonDas
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptxraviapr7
 
The Singapore Teaching Practice document
The Singapore Teaching Practice documentThe Singapore Teaching Practice document
The Singapore Teaching Practice documentXsasf Sfdfasd
 
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptx
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptxPISA-VET launch_El Iza Mohamedou_19 March 2024.pptx
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptxEduSkills OECD
 

Último (20)

Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptx
 
How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17How to Make a Field read-only in Odoo 17
How to Make a Field read-only in Odoo 17
 
Benefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive EducationBenefits & Challenges of Inclusive Education
Benefits & Challenges of Inclusive Education
 
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
CHUYÊN ĐỀ DẠY THÊM TIẾNG ANH LỚP 11 - GLOBAL SUCCESS - NĂM HỌC 2023-2024 - HK...
 
CAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxCAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptx
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 Sales
 
3.21.24 The Origins of Black Power.pptx
3.21.24  The Origins of Black Power.pptx3.21.24  The Origins of Black Power.pptx
3.21.24 The Origins of Black Power.pptx
 
How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17How to Add a New Field in Existing Kanban View in Odoo 17
How to Add a New Field in Existing Kanban View in Odoo 17
 
Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.Drug Information Services- DIC and Sources.
Drug Information Services- DIC and Sources.
 
General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and step
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17
 
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptxAUDIENCE THEORY -- FANDOM -- JENKINS.pptx
AUDIENCE THEORY -- FANDOM -- JENKINS.pptx
 
5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...5 charts on South Africa as a source country for international student recrui...
5 charts on South Africa as a source country for international student recrui...
 
Diploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdfDiploma in Nursing Admission Test Question Solution 2023.pdf
Diploma in Nursing Admission Test Question Solution 2023.pdf
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
 
The Singapore Teaching Practice document
The Singapore Teaching Practice documentThe Singapore Teaching Practice document
The Singapore Teaching Practice document
 
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptx
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptxPISA-VET launch_El Iza Mohamedou_19 March 2024.pptx
PISA-VET launch_El Iza Mohamedou_19 March 2024.pptx
 

Seed Bank Design: Seed Drying Rooms

  • 1. •• Millennium Seed Bank Project, Wakehurst Place, Ardingly, West Sussex RH17 6TN, UK © Copyright 2009, Board of Trustees of the Royal Botanic Gardens, Kew www.kew.org/msbp Seed bank design: seed drying rooms Simon Linington and Keith Manger, Seed C Technical Information Sheet_11 onservation Department The effective drying of orthodox seeds prior to cold storage is the key to successful seed banking. Drying prolongs storage life, allows seeds to tolerate extreme temperatures, prevents germination, and reduces attack by predators and pathogens. For long-term conservation, the aim is to reduce seed moisture status to 15% equilibrium relative humidity (eRH) at 15ºC. This is about 3-7% moisture content (on a fresh weight basis), depending on the oil content of the seeds. Technical Information Sheet_11 Equipment specifications Further reading Linington, S.H. (2003). The design of seed banks, pp. 591-636. In: R.D. Smith, J.B. Dickie, S.H. Linington, H.W. Pritchard and R.J. Probert (eds), Seed Conservation: turning science into practice. Royal Botanic Gardens, Kew. A dry room is the most appropriate drying method when you need to dry large quantities of seed at the same time (see table below). Dry rooms also provide safe storage prior to seed cleaning and a suitable location to package samples for storage or to warm up frozen samples that have been removed from the cold room. This information sheet explains how to set up a dry room. Refer to Low-cost Drying (Technical Information Sheet_08) and Linington (2003) for other drying methods. Description Model/Product Supplier Insulation Panellised Styrofoam, 100mm thick Local refrigeration company Sorption dryer Dehumidifying systems Munters www.munters.co.uk Chilling facilities Refrigeration unit Local refrigeration company Stacking crates Plastic trays (ventilated) 600L x 400W x 193H, ref:21035 600L x 400W x 120H, ref:20016 Dollies, ref:91005 Allibert Handling www.allibert.com Hygrometer to measure seed moisture status AW-DIO sensor with HygroPalm 3 display unit or HygroClip SC04 sensor with HygroLog-D unit. Rotronic Instruments (UK) Ltd. www.rotronic.com Data loggers for measuring relative humidity Tiny Tag and Tiny View data loggers Gemini Data Loggers (UK) Ltd. www.geminidataloggers.com Please note that the above equipment is used by the Millennium Seed Bank Project and has been chosen carefully using our many years’ experience. The list of suppliers is for guidance only and does not represent an endorsement by the Royal Botanic Gardens, Kew. The manufacturer’s instructions must be followed when using any of the equipment referred to in this Information Sheet. Designing a dry room It is important to obtain specialist advice when creating a dry room. However, seed curators and conservation practitioners should understand the basic principles in order to guide the design. The fundamental principle is to create a sealed room with low relative humidity and a cool temperature (the MSB recommends 15% RH at 15ºC). Good insulation is also important to reduce energy usage in cooling and drying. The key questions when designing a dry room are: What size and shape should the room be? The maximum volume of material that will need to be dried at any one time will determine the size of room required. A small seed bank might require a volume of around 25m³, whereas an international seed bank is more likely to require a dry room in the region of 125m³. What is the likely moisture load? Apart from the seeds themselves, other sources of moisture need to be taken into account when calculating dry room size. Together, these make up the moisture load, expressed as kilograms per hour. Working to a slight positive pressure, the dryer should be able to maintain the required conditions under the potential moisture load from: • Wet seeds The moisture status and amount of seeds in the room at any one time will vary, so it is difficult to estimate the exact moisture load. Unless batches of very wet seeds will be placed in the room at frequent intervals, there is no benefit in designing for a ‘worst case scenario’. The system may fall outside the optimum conditions for a short amount of time, but the dehumidifier will then start to work more efficiently and will rapidly return the room to the desired moisture status. • People in the room A person carrying out non-strenuous work in a dry room will release approximately 60g water vapour per hour. • Moist air entering the room Depends on the frequency of door-opening, the size of the air-lock, and the external air conditions. • Fresh air make-up Depends on the number of people using the room. • Permeation through the structure This should be negligible. • Leakage into the dehumidifier Moisture leaking into the dehumidifier is likely to be zero for a well-sealed machine. What about working conditions for staff in the room? A fresh intake of oxygen into the room is required, to maintain safe working conditions for staff. With the exception of very small dry rooms, air entering via the door will not supply sufficient oxygen to the room. Allow for a steady 10% fresh air make-up via the dry-air duct work, into the process air flow. The supply of fresh air can be shut off when there is sufficient oxygen in the room. This is controlled via a carbon dioxide monitoring device, linked to an automated fresh air intake valve in the process air duct. Seek further technical advice if this option is used. Below: Tasmanian Seed Conservation Centre, Australia - dry room with sorption dryer unit and -20°C chiller cabinets for seed storage Below: Dry room at The Lombardy Seed Bank, University of Pavia, Italy, with collections in stacked crates Comparing seed drying facilities Drying capacity Cost (UK prices) Purpose-built dry room in excess of 500L of seed material £30,000 (converting an existing cold room into a dry room will be cheaper) Bespoke drying cabinet with desiccant dehumidifier unit 500L of seed material £15,000 Incubator-dryer about 100L of seed material £2,500-4,000 (incubator purchase price) Silica gel in a 60 litre drum up to 25L of seed materal £200 In order to avoid dehydration, staff should only work in the dry room for a maximum of 2 hours and should then drink plenty of water when leaving the dry room. Another problem associated with operating a dry room is a build-up of electrostatic charge due to the dry conditions. Use anti-static footwear and/or an anti-static gun, especially when dealing with tiny seeds. All room fixtures should be well-earthed
  • 2. If the total uncleaned peak seed volume is sufficiently small, (less than 25m³) one or two incubator-dryers might be a more appropriate option for drying. It is helpful to mark out the dimensions of the proposed dry room on the ground. Ideally, locate the dry room close to, or attached to, the seed cleaning area and adjacent to the cold room(s). An oblong-shaped room is better than a square one. Supplying dry air on one of the short walls and extracting it from the opposite wall will give a good air flow to most parts of the room (though ‘dead spots’ will exist). Depending on the frequency of access to the room and the humidity of the external conditions, an air lock (small lobby) may be required to minimise the entry of humid air into the room when the door is opened. A 2m² air lock will be large enough for at least one person holding a crate to enter easily. Include a secondary (emergency) exit door from the dry room. What materials should be used? Ideally, install a new prefabricated structure, either as a stand-alone room or within a larger existing room. Construct walls and ceiling with Styrofoam panels (100mm thick). For the floor, cover a moisture-proof membrane with Styrofoam insulation, and top with marine plywood and epoxy-resin screed. Doors must be well insulated and windows (including those in the doors) should be double-glazed. If an existing brick- or wood-built room is to be used, install a moisture barrier (perhaps glazed tiles or plastic sheeting) on all internal surfaces. Install thermal insulation on the outside of the walls (and ceiling). Both will reduce energy usage in maintaining the dry room conditions and the external insulation should help minimise condensation in the walls. How is the air dried and cooled? The drier must have enough capacity to deliver about six air changes per hour to the drying room. This is often the limiting factor. To estimate the likely suitability of a dryer, compare its airflow capability with six times the volume of the dry room. Confirm this with the supplier/installer. Note that refrigeration dryers are not designed to deliver this condition. The MSB recommends a rotary sorption dryer containing a silica gel or lithium chloride drying agent. If possible, install two dryers, each capable of coping with 66% of the moisture load. The dryer creates heat during the drying process and should ideally be placed outside the room (in a ventilated area). Connect the drier to the room via insulated supply and extract ducts, of sufficient diameter not to impede air flow. Possible layout of dry room facilities The direction of the air flow is indicated by the arrows. This ‘process air’ dries the room and should be supplied, via a chiller, high up at one end of the room and extracted low down at the other end of the room. The drying agent picks up moisture from the process air and is then re-dried by the second (‘reactivation’) air flow. Air is drawn into the dryer, heated, and passed over the drying agent. The wet air produced by this process needs to be ducted to the outside of the building. The location of the controlling humidistat is important. Place the humidistat halfway along one of the longer walls of the room. Construct a map of humidity in the working dry room, using an RH meter to guide where to best locate the stacks of crates for drying. If the dryer is located within the dry room, ensure that the process air mixes rapidly with the cooling system air. Duct the wet reactivation air out of the room. The chiller will need to be located in the room and be capable of cooling the heat load from the dryer, achieving a room temperature of 15ºC. Reactivation air flow Process air flow Prefabricated dry room constructed with 100mm Styrofoam panels Humidistat Dryer Chiller Flourescent lights Stack Air extract (low) Process air supply (high) Duct either over or alongside room Air lock with 2 doors + windows Bench with electrical sockets Double glazed window Fresh air intake Stack Secondary exit Below: Crates stacked on moveable trolleys in the MSB dry room, with seed collections contained in porous bags Assess the likely collection intake per month during a typical year and identify the peak volume of material (for some seed banks, the dry room may need to hold a whole year’s collections). The number of seeds per collection, and the size of these seeds will greatly affect the volume estimations. Make these estimations on the basis of uncleaned collections, unless the seeds will definitely be cleaned beforehand. Assume that drying will take at least one month. Seed drying room: worked example If the volume of an ‘average’ un-cleaned seed collection (V) = 0.002m³ Number of collections in dry room during peak period (N) = 500 Assume that collections are spread in thin layers on paper inserts, within self-stacking crates on trolleys. If collections are to be held in bags, less space is required but drying time will increase. Height of crate (H) = 0.12m Width of crate (W) = 0.4m Length of crate (L) = 0.6m Proportion of crate filled (P) = 0.25 (especially if thin-layer drying) Trolley Height (Z) = 0.3m Number of collections per crate (A) = (H * W * L * P) / V = 3 (round down to avoid part collections in a crate) Number of crates (B) = N / A = 167 (round up) A stack of self-stacking crates on a trolley should not exceed a height of 2m. Number of crates in stack (C) = (2 - Z) / H = 14 (round down) Number of stacks (D) = B / C = 12 (round up) Floor area of stacks (E) = D * W * L = 2.88m² In order to allow sufficient working space (including a table) and good air circulation, crates should only occupy about 25% of the floor area. Therefore, the total floor area will need to be 4 times the area occupied by the crates. Required dry room floor area (F) = E * 4 = 11.52m² The height of the room is likely to be around 2.5m. Dry room volume (G) = F * 2.5 = 28.8m³