HPCL Rajasthan refinery fire: CDU restart by May 2026

What HPCL disclosed in its latest update

Hindustan Petroleum Corporation Ltd (HPCL) has said a leak was the likely cause of the April 20 fire at its joint venture refinery in Rajasthan. In a stock exchange filing, the company said restoration work is underway and is expected to be completed within three to four weeks. HPCL also outlined a restart window for the crude distillation unit (CDU), which is the primary processing unit in a refinery. The company said the CDU restart is anticipated in the second fortnight of May 2026. The update follows the incident that occurred a day before the refinery’s planned inauguration.

The April 20 fire at the Rajasthan JV refinery

A major fire broke out near the main unit of the newly built refinery project on April 20, 2026. The facility, HPCL Rajasthan Refinery Ltd (HRRL), is a Rs 79,450-crore greenfield refinery and petrochemical complex located in Rajasthan. The fire occurred in the CDU section and sent thick black smoke into the sky, according to reports from the site. HPCL said the emergency response teams brought the incident under control quickly. The company also stated there was no loss of life or injury to personnel.

What the investigation says about the likely cause

HPCL initially indicated that the fire appeared to have been caused by leakage of hydrocarbons through one of the valves or flanges in the heat exchanger circuit. In its subsequent filing, the company provided a more specific suspected source based on circumstantial evidence. HPCL said the fire is suspected to have been triggered by leakage from the pressure gauge tapping point. The company identified this point as being on the vacuum residue exchanger inlet line. HPCL added that detailed post-incident investigations confirmed the event was localised to a specific part of the CDU heat exchanger area.

Extent of damage: heat exchanger stack affected

HPCL said the fire was confined to the heat exchanger stack in the CDU. The company reported that six exchangers and associated auxiliary equipment were impacted. HPCL also said that no other section of the refinery suffered any impact. In its earlier disclosure, the company said the CDU, the vacuum distillation unit (VDU), and other units in the CDU section were quickly isolated. HPCL stated that structural safety across the facility remained intact, as per its assessment shared in updates.

Restoration timeline and CDU restart window

HPCL said restoration work is in progress and is expected to be completed in the next three to four weeks. It also guided that the CDU restart is anticipated in the second fortnight of May 2026. This restart timing matters because the CDU is typically the anchor unit that enables a refinery to move from commissioning to stable output. HPCL has not provided a day-specific restart date, but the stated window gives the market a timeline for bringing the primary processing section back. The company also said it is undertaking remedial measures alongside the restoration activity.

Commissioning status of other units and product trials

Alongside the CDU update, HPCL said other secondary units are at an advanced stage of commissioning and progressing as planned. It also said trial production of key products is expected to begin within May 2026. The company listed LPG, motor spirit (petrol), high-speed diesel and naphtha as the main products expected to enter trial runs. HPCL said trial production would be followed by stabilisation and full commissioning of the units. The company’s disclosures indicate commissioning activity was underway before the fire and continues for units not affected by the incident.

Inauguration postponed; government probe initiated

The refinery’s scheduled dedication on April 21, 2026, was postponed after the fire, with a revised date to be announced. The postponement came a day after the incident and was described as a precautionary measure in disclosures. Separately, the Ministry of Petroleum and Natural Gas instituted an inquiry into the incident. The ministry’s probe team is led by former MRPL Managing Director M Venkatesh and includes four members. HPCL has also said the cause of the fire and its impact on the unit were being investigated.

Key facts at a glance

Market and operational impact: what is known so far

HPCL has said the financial and operational impact is under assessment, and prima facie is not expected to be material. From an operational standpoint, the incident occurred during a sensitive phase, as the project was close to a scheduled inauguration and commissioning milestones. But HPCL’s filings emphasised that the damage was localised and that other sections remained unaffected. The company also stated that secondary units continue commissioning progress as per plan. Separately, industry reports noted the greenfield refinery and petrochemical complex is expected to begin commercial operations on 1 July 2026.

Why this incident matters for commissioning and safety oversight

A fire in the CDU section, even when contained, draws attention because this unit is central to refinery operations and commissioning readiness. The suspected source being a hydrocarbon leak at a measurement or connection point underscores the importance of checks around pressurised lines, fittings, and instrumentation during commissioning. The postponement of the inauguration and the oil ministry’s probe indicate heightened scrutiny, especially given the project scale and its role in expanding domestic refining and petrochemical capacity. HPCL’s step-by-step restart guidance, including a specific fortnight for CDU resumption, provides a near-term operational reference point for stakeholders.

Conclusion

HPCL has attributed the April 20 Rajasthan refinery fire to a suspected leak in a heat exchanger circuit area and said the incident was confined to the heat exchanger stack affecting six exchangers. Restoration is expected to take three to four weeks, with CDU restart anticipated in the second fortnight of May 2026. Trial production of LPG, petrol, diesel and naphtha is expected within May, followed by stabilisation and commissioning. A revised inauguration date is awaited, while a four-member oil ministry panel led by former MRPL MD M Venkatesh continues its inquiry.