The Senate yesterday confirmed economist Alan Greenspan as chairman of the Federal Reserve by a vote of 91 to 2.

Greenspan, 61, will succeed Paul A. Volcker, who was appointed to the job by President Carter in 1979. Volcker was reappointed by President Reagan in 1983 and offered another four-year term, which he declined.

No date has been set for a swearing-in ceremony, but it probably will occur early next week.

Greenspan, who was chairman of the Council of Economic Advisers in the Ford administration, was head of a New York economic consulting firm, Townsend-Greenspan & Co., when he was named to the Fed chairman ship. The firm was dissolved recently in line with a commitment Greenspan made to the Senate Banking Committee during confirmation hearings.

In a statement issued by the Fed after the confirmation vote, Greenspan said, "I am obviously gratified and I thank the Senate."

Greenspan is a conservative economist who is expected to continue to pursue Volcker's anti-inflation policies. However, he is much more inclined to reduce or eliminate many legal and regulatory restrictions on financial institutions than Volcker has been.

"Of all the prospective chairmen the Reagan administration might realistically have been expected to appoint, except for Chairman Volcker, Greenspan promises to be the most willing to pursue anti-inflationary policies," said Banking Committee Chairman Sen. William Proxmire (D-Wis.).

Democratic senators Bill Bradley of New Jersey and Kent Conrad of North Dakota voted against confirmation. Declared Bradley, "I think Alan Greenspan is a man of ability and great integrity, but I have several concerns about his policy views. In particular, I am concerned that he will move too rapidly toward {banking} deregulation rather than showing the same caution as Chairman Volcker. ... . My personal preference would have been for the administration to have prevailed upon Chairman Volcker to stay on for another term.