Arnold miller has apparently won re-election as president of the United Mine Workers, but dissension in the union lingers, threatening labor peace in the coal fields and the nation's energy production.

A post-election challenge to Miller's victory Tuesday is possible, and government and industry officials expressed concern yesterday that continued bickering could obstruct negotiations for a new contract by Dec. 6 and lead to a strike before year's end.

Challengers Lee Roy Patterson and Harry Patrick conceded defeat, but Patterson, who ran second, indicated he may challenge the election on grounds that the ballot was rigged against him.

Wire-service tallies showed Miller with a comfortable lead, based on incomplete returns. But Patterson and Patrick together got about 60 per cent of the vote, meaning Miller lacks a demonstration of majority support from his union as he heads into contract talks this summer or fall.

With 69 per cent of 858 locals reporting, anunofficial tally by United Press International showed Miller with 44,126 votes, Patterson with 37,311 and Patrick with 26,587. An Associated Press count showed a roughly similar breakdown with fewer locals reporting.

An official count will be made in July. The union's executive board, dominated by Patterson supporters, has the power to invalidate the election and order a new one, although Patterson appeared less certain about protesting the election yesterday than he was during the campaign. One of his running mates, Gene Mitchell, called for unity behind Miller and said he would not support a challenge.

At a press conference in Charleston, W. Va., Miller, a 54-year-old black-lung victim who was first elected in a successful reform revolt five years ago, called on "all those who were on the losing side in this democratic election to come forward and recognize who the enemy is, which is the operators."

As for the future of the 277,000 member union, he said, "I think it looks good. I think we're going to get together."

Patrick, a former Miller ally, also called for a united front and appealed to Miller to "provide the sort of leadership that will make unity not just a word but a reality." Patrick, now secretary-treasurer of the union, saide he will be going back to work in the mines but might run again for union office.

Miller ran strongest in West Virginia and Pennsylvania, but lagged in the West, where coal production is expanding, and among young miners, who are demanding more militancy at the bargaining table, including a right to strike over local grievances.

Miller apparently benefited from incumbency and the union's lucrative 1973 contract, while Patterson suffered form association with the former regime of W.A. (Tony) Boyle and suggestions that the would consider merger of the UMW and the United Steelworkers. He and Patrick split the anti-Miller vote too closely for wither to pull ahead of Miller.

The UMW election was the second rank-and-file union vote this year that pitted "reform" factions against oldguard elements, producing mixed results.

In the miners' election, Miller and Patrick, leaders of the 1972 reform drive, together got nearly two-thirds of the vote. "At least the reform movement remained strong and that's the important thing," said Joseph L. Rauh Jr., Washington lawyer ofr the 1972 Miners for Democracy effort.

In the United Steelworkers election in February, the union establishment prevailed as Lloyd McBride defeated a militant young rebel. Edward Sadlowski. But McBride has already shaken up the union by seeking the resignation of USW department heads to give him a free hand with reorganization.