Whether it's through stocks, bonds, ETFs, or other types of securities, all investors love seeing their portfolios score big returns. However, when you're an income investor, your primary focus is generating consistent cash flow from each of your liquid investments.While cash flow can come from bond interest or interest from other types of investments, income investors hone in on dividends. A dividend is the distribution of a company's earnings paid out to shareholders; it's often viewed by its dividend yield, a metric that measures a dividend as a percent of the current stock price. Many academic studies show that dividends make up large portions of long-term returns, and in many cases, dividend contributions surpass one-third of total returns.Enterprise Products Partners in FocusBased in Houston, Enterprise Products Partners (EPD) is in the Oils-Energy sector, and so far this year, shares have seen a price change of 7.66%. The provider of midstream energy services is currently shelling out a dividend of $0.43 per share, with a dividend yield of 6.03%. This compares to the Oil and Gas - Production Pipeline - MLB industry's yield of 7.1% and the S&P 500's yield of 1.93%.In terms of dividend growth, the company's current annualized dividend of $1.72 is up 3.1% from last year. Enterprise Products Partners has increased its dividend 5 times on a year-over-year basis over the last 5 years for an average annual increase of 4.93%. Any future dividend growth will depend on both earnings growth and the company's payout ratio; a payout ratio is the proportion of a firm's annual earnings per share that it pays out as a dividend. Enterprise Products's current payout ratio is 113%. This means it paid out 113% of its trailing 12-month EPS as dividend.EPD is expecting earnings to expand this fiscal year as well. The Zacks Consensus Estimate for 2018 is $1.61 per share, which represents a year-over-year growth rate of 21.97%.Bottom LineInvestors like dividends for a variety of different reasons, from tax advantages and decreasing overall portfolio risk to considerably improving stock investing profits. But, not every company offers a quarterly payout.Big, established firms that have more secure profits are often seen as the best dividend options, but it's fairly uncommon to see high-growth businesses or tech start-ups offer their stockholders a dividend. Income investors must be conscious of the fact that high-yielding stocks tend to struggle during periods of rising interest rates. That said, they can take comfort from the fact that EPD is not only an attractive dividend play, but is also a compelling investment opportunity with a Zacks Rank of #2 (Buy).Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Enterprise Products Partners L.P. (EPD): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research