* Sees at least 150 mln euros savings a year by end-2020
* Sets 3 bln euros EBITDA target for 2030
* But delays cash flow goal by one year until 2019
* Shares drop, biggest fall in mid-cap MDAX (Adds comments from analyst, CEO, detail and background)
BERLIN, Oct 9 (Reuters) - German minerals company K+S plans to combine its salt and potash businesses to make savings and target customers more effectively, it said on Monday, disappointing investors hoping for a more far-reaching overhaul.
Shares in the world's biggest salt producer and No.5 seller of potash fell as much as 7 percent after it also delayed by a year to 2019 a goal to return to positive free cash flow.
K+S has been grappling with a slow recovery in potash prices and in August scrapped medium-term profit targets.
CEO Burkhard Lohr has continued a strategy review started by his predecessor Norbert Steiner, who stepped down in May, looking at ways to boost the value of its salt operations.
On Monday, the firm said its salt and potash divisions would in future jointly focus on customers such as agricultural and chemicals firms to improve product development and make savings in production, purchasing and other areas.
It expects the overhaul to deliver annual synergies of at least 150 million euros ($176 million) by the end of 2020.
K+S also set a goal of 3 billion euros for earnings before interest, tax, depreciation and amortisation (EBITDA) by 2030, compared with the 519 million euros achieved last year.
But it delayed the expected return to positive free cash flow, citing currency effects and "inefficiencies" with ramping up production at its new Bethune mine in Canada.
"K+S is driving its new structure with a lot of verve but the positive effects cannot be expected soon," said Baader Bank analyst Markus Mayer, who has a "Sell" rating on the stock.
"The market of course wonders how valid the new long-term (EBITDA) goal is given that the short-term targets will not be met," he said.
At 1430 GMT, K+S shares were down 6.8 percent at 20.98 euros, the biggest drop on Germany's mid-cap index MDAX.
Analysts had been hoping for more far-reaching changes - for example a shutdown of uncompetitive mines in Germany or a possible stock market listing of the salt unit.
But a person familiar with the company's thinking told Reuters last week that the Kassel-based firm would not float its salt activities.
CEO Lohr said K+S had considered all options, including spin-offs, and would benefit from the planned changes.
"Today we are making the first move" with the new structure, he said on a conference call. "I'm sure we will be able to win support of the markets again when we take the next step."
($1 = 0.8522 euros) (Reporting by Andreas Cremer; Additional reporting by Elke Ahlswede in Frankfurt; Editing by Victoria Bryan and Mark Potter)