Norfolk-based filtration specialist Porvair is accelerating a £6m investment drive to bolster its manufacturing output and create new jobs in King's Lynn.

The EDP Top 100 company is searching for six chemists from within East Anglia to join its subsidiary business Seal Analytical – a manufacturer of water quality analysis equipment for laboratories – based at Porvair's headquarters in Regis Place, King's Lynn.

It comes as the company looks to invest across the group, with plans to expand UK facilities at New Milton near Christchurch, improve its US manufacturing output in Caribou, Maine, and increase capacity at its metal filtration factory in Xiaogan, China.

The company saw revenues grow a record 10pc, from £76.5m in 2012 to £84.3m last year, while its pre-tax profit was up 25pc, from £6.3m to £7.8m over the same period. The better-than-expected performance helped drive down net debt from £5m in 2012 to £3.5m last year.

Ben Stocks, chief executive of Porvair, said the group added 20 jobs to its 650-strong workforce last year – and expected to do the same again in 2014.

'There was a little bit of acquired growth last year,' he said. 'But the rest was organic.

'Our metal filtration business picked up after a slow start, while the majority of the growth came from the creation of new products, which is at the heart of our strategy.

'On average we make about 10,000 different products per year. About a third of our sales come from that.

'But 2013 was a significant year for us because we got we some very large contracts, which meant we could accelerate the investment.'

Across the group, revenues in the metal filtrations business increased to £28.5m from £28m in 2012, while microfiltration revenues increased 15pc to £55.8m.

But while the group aims to wipe out its deficit in 2014, the firm may seek a new finance deal to facilitate further acquisitions in the future, Mr Stocks said.

He added: 'The board expects that provided economic conditions allow, the underlying business will continue to grow this year.'