Running water in the Antarctic
People staying at the South Pole must endure many difficulties and hardships. Accommodation with reasonable comfort, services and sufficient supplies of food and water help them cope with the tough conditions.DATE 2017-07-13 AUTHOR Birgitta Lundblad
It’s like living on the inside of a table-tennis ball. All you see is snow and a complete cloud cover at low altitude. Crevasses and the horizon are both invisible, so it is dangerous to move into unknown territory. Winds are severe, the temperature is -30ºC. This is what it can be like at Scott Base in the Antarctic – in the summertime. In winter, temperatures can fall to below -50ºC!
The Antarctic is the driest, coldest and windiest continent in the world. In July 1983 the lowest recorded temperature on the earth’s surface was measured at -89.2ºC. The Antarctic presents extremely difficult conditions. Winds generated by weather near the coast interact with winds produced when the very cold, dense air over the continent’s ice sheet flows downwards towards the lower coastal areas. The resulting wind is strong and persistent. Wind speeds exceeding 200 km/hour have been recorded.
In spite of these hardships, the Antarctic attracts a lot of scientists and researchers every year who have discovered the importance of the Antarctic and Southern Ocean as an indicator of the Earth’s health, a driver of global processes, a place of unique ecosystems and a chronograph holding a wealth of geological information.
New Zealand’s involvement in the Antarctic began as early as in 1923, when activities were closely associated with those of Great Britain. Scott Base, opened in 1957, is one of the first bases to be established in the Antarctic and New Zealand’s permanent base on the continent. The base is situated on Pram Point at the end of the Hut Point Peninsula on Ross Island.
A base of strategic importance
Antarctica New Zealand, created through an act of parliament, is responsible for the development, management and execution of New Zealand’s activities in Antarctica including Scott Base. The aim of the organization is also to maintain and enhance the quality of the country’s scientific research as well as national and international cooperation on Antarctic matters.
The science supported by Antarctica New Zealand fits within three research themes; the Antarctic Physical Environments Research, the Southern Ocean Research and the Antarctic Ecosystems Research. Scientific research from a wide variety of disciplines is supported within these themes.
Scott Base provides services and accommodation for the many research parties and groups who visit Antarctica during different seasons. The base accommodates up to 85 people in summer and a skeleton staff of 10-14 in winter. It is managed somewhat similarly to a boarding hostel, with shared bedrooms, one large dining room and a kitchen complete with chefs.
Each year Antarctica New Zealand employs staff for the base; some for the summer period (October-February) and others, referred to as the winter-over crew, who will stay on for the entire year (October-October). The New Zealand Defence Force contributes with personnel who help provide the essential services to keep Scott Base running. The staff work hard to ensure that supplies of heat, electricity, fresh water and food are maintained.
Field parties, equipped with the correct clothing and a balanced diet, need to ensure their field accommodation is equally well designed. They use special polar tents with separate groundsheets made to withstand high winds and wind-driven ice particles. By using a mattress and two sleeping bags they can get a warm night’s sleep.
Field parties may camp up to a hundred days in an Antarctic summer. The weather dictates how much work can be done. During the most demanding weather conditions, days are best spent working in the safety of the tent. In periods of good weather during the 24 hours daylight of midsummer the parties may work around the clock to compensate for time spent lying up.
In most parts of the world we often put ice in our drinking water to make it cool and refreshing enough. In the Antarctic the need is the opposite; here the problem is to maintain the drinking water above its freezing point. A plate heat exchanger from Alfa Laval is installed at Scott Base for this purpose.
“Maintaining and operating Scott Base’s ‘life support systems’, such as electricity and water production, is a critical issue. Without these systems we couldn’t maintain our presence in Antarctica,” says Kevin Rigarlsford, Maintenance and Field Engineer at Antarctica New Zealand.
Heat for the base is produced mainly from energy recovered from the power generation plant. This energy is recovered by marine heat exchangers attached to the generators. Supplementary energy is supplied by diesel-fired burners when required. This maintains a heating loop at approximately 60-70°C that runs throughout the base. Indoor temperatures at the base are typically set at 18°C for reasons of fuel conservation.
Fresh water production is another crucial area of operation. “Through a Reverse Osmosis plant we produce about 8 000 litres per day,” says Rigarlsford. “Water conservation is high on our priorities due to the amount of energy required for its production.”
There are four insulated tanks that provide a storage capacity of 140 000 litres in total. At least 75% of this water amount must be kept as a fire fighting reserve. Generally storage levels are maintained at around the 90% mark.
So how do they keep 140 000 of fresh water from freezing? “Quite simple really,” explains Rigarlsford. “The water is continually circulated back to the powerhouse where it is then passed through an Alfa Laval plate heat exchanger attached to the heating loop. People often ask about the problems associated with keeping the water from freezing in Antarctica, but really the Alfa Laval solution has made this one of the least troublesome aspects of our operation”.
Waste management regulations
There are international agreements that deal specifically with protection of the Antarctic environment. New Zealand has enacted laws to implement these agreements. Where relevant, New Zealand environmental laws also apply to Antarctica New Zealand’s activities.
Requirements for waste management in the Antarctic include waste minimization through source reduction and recycling, storage, disposal and removal of waste and cleaning up sites once activities have been completed.
Antarctica New Zealand has developed a waste management policy that provides detailed procedures for handling waste material. These include sewage disposal, both at the Scott Base and at field camps. No waste can be disposed of on ice-free land or in freshwater and disposal on the ice is allowed only during special circumstances.
The Scott Base produces 8 000 litres of wastewater per day. The wastewater treatment plant, taken into service in 2002, treats all human waste and grey water (e.g. washing water) produced at the base by a process of screening, clarifying, biological treatment and disinfection. The system already exceeds the requirements of international agreements for environmental protection in the Antarctic. But people responsible for waste management at the Scott Base are now investigating solutions that can improve the process even further.
Alfa Laval / Antarctica New Zealand cooperation
Antarctica New Zealand’s Scott Base has a need of approximately 7-8 000 litres of potable water a day in summer and 3 000 litres a day in winter for staff and visitors.
With temperatures descending to -30ºC in summer and -50ºC in winter the challenge is to maintain the drinking water above its freezing point.
A plate heat exchanger from Alfa Laval handles this task to full satisfaction. The water from the four insulated storage tanks is continually circulated back to the powerhouse where it is then passed through the plate heat exchanger attached to the heating loop.
“The Alfa Laval solution is extremely reliable,” says Kevin Rigarlsford, Maintenance and Field Engineer at Antarctica New Zealand. “The unit is impressive for its relatively small size and fits neatly in amongst the jungle of pipework that resides in the powerhouse.”
“Our installation at Scott Base is an exciting project,” says Marian Ioan, Sales Engineer at Alfa Laval New Zealand. “This must be our ‘coolest’ installation ever.”