Furthermore, we continue to advance the required environmental permits. And as studies progress, the project demonstrates the potential to unlock important value for Nexa through economies of scale, cost improvement and extension of asset life. We expect to submit this project for approval during the first quarter of next year. Now, I will turn over the call to Jose Carlos del Valle, our CFO, who will present our financial results. Jose, please go ahead.
Jose Carlos: Thank you, Ignacio. Good morning to everyone. I will continue on slide 10. As you can see, beginning with the chart on your upper left, total consolidated debt revenues for the third quarter decreased by 8% year-over-year mainly due to lower Zinc LME prices and lower smelting sales volumes. Compared to the second quarter of 2023, net revenues increased by 4% as a result of higher mining production and metal sales volumes, partially offset by lower Zinc prices. In the first nine months of the year, consolidated net revenues reached $1.9 billion, down by 14% compared to the same period a year ago. In terms of profitability, consolidated adjusted EBITDA in the third quarter of 2023 was $82 million, compared to $121 million in the third quarter of 2022.
This lower performance was mainly explained by lower Zinc metal prices. Compared to the second quarter of 2023, adjusted EBITDA increased 13%, mainly due to higher mining and metal sales and lower costs in Brazil, which were partially offset by lower Zinc prices and FX rate. In the first nine months of this year, consolidated adjusted EBITDA reached $286 million, down by 55% from the same period last year. Also explained by the reasons I mentioned in the moment. Now let’s move to the next slide 11. On the top left of the slide, we can see that in the first nine months of 2023, we invested $198 million in CapEx, of which sustaining investments including mine development totaled $185 million. The total investment in the third quarter was $82 million.
With respect to mineral exploration and freight evaluation, we’ve updated our guidance for the year and we now expect to be at $100 million in 2023 which is a reduction of $10 million from the previous guidance mainly due to initiatives to improve our cash flow for the year. In the first nine months of 2023 we invested a total of $69 million of which $39 million were related to mineral exploration and mine development to support our exploration activities. Now let’s move on to the next slide in which I will discuss our cash flow generation in the third quarter of the year. For the third quarter of 2023 and starting from our $82 million of adjusted EBITDA net of non-operational items, we paid almost $38 million related to interest and taxes and spent $75 million in sustaining CapEx and HS&E inner operations including Aripuanã.
Additionally loans and investments and dividend received and paid had a positive net impact of $3 million. We then had a negative impact of also $3 million due to the effects of foreign exchange on our cash and cash equivalents. This was driven by the depreciation of the Brazilian Real against the US dollar during this period. Finally, there was a positive contribution of $93 million from an improvement in working capital, which is part of the result of our ongoing program of cash optimization measures for 2023. Now, combining all these effects, our free cash flow in the third quarter of 2023 was $14 million. Now moving to slide 13. On this slide, you can see that our liquidity remains healthy and that we continue to present a solid balance sheet with an extended term debt profile.
Cash balance increased and net debt declined in the third quarter of 2023 as a result of low liquidity at the end of the third quarter of 2023 was approximately $722 million, including our undrawn revolving trade facility of $300 million. I would like to highlight that we recently announced a successful closing of a five-year $320 million sustainability-linked revolving credit facility, which became effective on October 20, 2023. This new revolving credit facility replaces Nexa’s 2019 $300 million RCF that was set to mature in October 2024. The amounts drawn are subject to an initial interest rate of 1.6% plus the term SOFR. The applicable margin is subject to compliance with carbon reduction KPIs, reflecting Nexa’s unwavering commitment to reducing its carbon footprint.
