By Adam Whittaker

Shell's traders continue to benefit from volatility triggered by the conflict in the Middle East, but lost Qatari volumes have squeezed output, highlighting the conflict's uneven impact on the world's big energy companies.

The British energy major said Tuesday that its gas-trading division is expected to report significantly higher results in the second quarter than the first after benefiting from higher gas prices, which are typically delayed due to price-lag effects in contracts. Shell's oil traders are also expected to post a robust performance, continuing on from the bumper profits they netted at the start of the year.

The war between the U.S. and Iran, which broke out in February, drove oil-and-gas prices higher and has also caused dislocations across energy markets that Shell's vast trading desks have been able to cash in on.

The company said its oil traders' result is expected to be in line with the prior quarter. While Shell doesn't break out its trading performance, adjusted earnings within its chemicals and products division, which houses its oil traders, surged to $1.925 billion in the first quarter, swinging from a loss at the end of last year.

Conflict kept oil prices high through most of the second quarter, but prices have fallen considerably since the two sides reached a preliminary peace agreement in mid-June. Despite slow progress in the peace talks, supply across the Persian Gulf's Strait of Hormuz, through which 20% of the world's crude oil typically flows, is rebounding and analysts have cut their price forecasts for the remainder of the year. However, intermittent exchanges of fire continue to trigger oil price volatility.

Still, while Shell's traders gained, production in the company's integrated gas unit suffered due to the fighting.

Integrated gas production will fall significantly quarter-on-quarter, Shell said in its update, though it lifted its estimate slightly to 610,000 to 650,000 barrels of oil-equivalent a day due to strong production at assets outside of the region. It had previously guided for 580,000 to 640,000 BOE a day. The unit produced 909,000 BOE a day in the first quarter, with the sharp fall down to the conflict's hit to output in Qatar, one of the world's most important exporters of gas.

In May, Shell said it had lost roughly 10% of its total production due to damaged or shut-down assets in Qatar, where it owns the massive Pearl gas-to-liquids plant and has a 30% stake in a QatarEnergy LNG facility.

The Pearl site was hit by an Iranian attack in March. One facility at the plant--referred to as a train--was damaged and the company is hopeful it can get it back up and running early next year, Chief Executive Wael Sawan told the WSJ Leadership Institute CEO Summit in June. Production at the other train was shut down, with Shell expecting to restart production once the situation in the strait allows.

Second-quarter volumes of liquefied natural gas are expected between 7.4 million and 7.8 million metric tons after the company raised its guidance from 6.8 million to 7.4 million metric tons.

Upstream production--the extraction of crude oil and natural gas--is expected to be 1.75 million to 1.85 million BOE a day, which is above its previous guided range of 1.62 million to 1.82 million BOE a day.

The company expects refining margins to rise to around $20 a barrel from $17 a barrel in the first quarter with its refinery utilization rate around 100%.

Shares traded 3.2% higher Tuesday morning.

Write to Adam Whittaker at adam.whittaker@wsj.com