Constructing a green and low-carbon integrated energy system for urea chemical industry in rural areas, utilizing abundant renewable energy sources, is of great significance for achieving dual-carbon goals and promoting the low-carbon transformation of the chemical industry. This paper proposes a green and low-carbon integrated energy scheduling method for rural urea chemical industry. First, a framework for a rural urea chemical industry integrated energy system based on new energy sources is constructed, combining waste heat recovery and temperature-controlled biogas fermentation tanks to improve system energy utilization efficiency. Then, to address the impact of various uncertainties in the intraday scheduling process, a Markov decision process model for the optimal scheduling of the rural urea chemical industry integrated energy system is established, and an approximate dynamic programming (PLF-ADP) algorithm based on a multidimensional piecewise linear function approximation of the value function is proposed. A piecewise linear function is introduced to approximate the value function in the Bellman equation. Simulation examples show that the proposed multidimensional PLF-ADP algorithm has an optimization error of 3.3%, and can obtain a near-globally optimal real-time scheduling strategy through the coordinated operation of various devices in the rural urea chemical industry system under random conditions, ensuring the economic efficiency of system operation.