Marsden Point Refinery

The Marsden Point Refinery was built in 1964 and is located about 40km from Whangarei, New Zealand. It is the country’s only refinery and is operated by The New Zealand Refining Company (NZRC).

Marsden Point was selected as the location of the refinery due to the availability of a deepwater harbour and the area’s low earthquake risk. In addition, the harbour was close to some of the major North Island markets. Significant amount of land was also available near the site.

The refinery processes 35 million tonnes of crude oil annually and supplies 80% of New Zealand’s fuel products. Major oil companies including BP, Chevron, Mobil and Aotea Energy are share owners in the refinery.

Marsden Point construction and infrastructure

Prior to the construction of the Marsden Point Refinery the required fuel products were imported into New Zealand by oil companies. With rising fuel prices the government proposed the construction of a new refinery in 1956. Construction began in 1962 and required an investment of NZ$1.84bn.

In the mid-1980s the refinery was expanded to increase its production capacity with an investment of $1.8bn. The expansion added a hydrocracker unit, storage tanks, environmental treatment units and other facilities to the refinery. A $180m upgrade programme called Future Fuels Project was completed in 2005. It enabled the refinery to remove sulphur from diesel and benzene from petrol. Completion of the project helped the refinery supply cleaner fuels to the New Zealand market.

In 2005 NZRC launched a $190m expansion programme, called Point Forward Project, for the refinery. The expansion started in January 2008 and was completed in July 2010.

The expansion increased the production capacity of the refinery by 15% to 135,000 barrels per day from 106,500 barrels per day. It was undertaken to fulfil the growing demand for fuel products in New Zealand, which is projected to increase over the next 20-30 years.

The expansion project removed bottlenecks at the crude distillation unit, modified the heat exchangers, added bigger vessels and furnaces pumps to the refinery. New kerosene stripper and pre-flash drums were also added. The pipe works of the refinery were also upgraded to handle the increased output.

Contractors and processing

WorleyParsons, Shell and UOP carried out the front-end engineering and design (FEED) for the expansion project. A 3D electronic model of the project was created at WorleyParsons’ engineering production centre at Beijing.

The refining process at Marsden Point includes three steps – separation, conversion and purification. In the first step, crude oil is separated into different hydrocarbons including refinery gas, petrol, kerosene, light and heavy gas oils, and long residue. Separation is carried out using distillation process.

The refinery gas obtained through separation is converted into hydrogen sulphide using the Shell ADIP process, which involves reacting refinery gas with a solution of diisopropanol amine. The long residue is processed in the butane deasphalting unit to produce petrol and asphaltic compounds. In the second step sulphur is removed from the petrol, kerosene and light and heavy gas oils using the desulphurisation process. After this process chemical conversions processes such as catalytic reforming and hydrocracking are used to obtain the desirable compounds.

The third step includes purification of the hydrogen sulphide and naphtha obtained after the first two steps. Purified naphtha and hydrogen sulphide are later blended with the other hydrocarbons for sale.

Marsden output

The Marsden Point refinery produces premium and regular petrol, diesel, automotive fuels and kerosene for the New Zealand market. It also produces jet fuel, fuel oils (LFO, HFO and HBFO) and bitumen.

Pipeline route

During the refinery’s expansion in the 1980s, a 170km pipeline called Refinery to Auckland Pipeline (RAP) was built. The pipeline carries half of the refinery’s production to Wiri in South Auckland where it is stored and later distributed by road.